New Dyeing Process in 2022 (Green Dyeing Technology)-1

As society advances and people\'s quality of life improves, people pay more and more attention to the environment and their own health. Wearing “green textile” and “ecological textile” has become the life necessities of people in these days world. Green dyeing technology is the most important trend in the development of textile dyeing in the future.

Green dyeing technology is characterized by the use of harmless dyes and auxiliaries as well as the dyeing and processing of textiles using environmentally friendly or low-emission processes. The amount of dyed waste water released after dyeing is small, and it is easy to filter and dispose of, as is the amount of energy consumed, and the dyed goods are \"green\" or ecological textiles. For this purpose, numerous research projects have been carried out at home and abroad in recent years and various innovative dyeing processes mpresented and promoted with less pollution or lower ecological requirements.

Waterless dyeing, energy-saving dyeing, solubilizing dyeing, new dyeing, short-process, multi-effect dyeing and finishing, computer application and controlled dyeing are examples of the new dyeing process.

Dying with natural dyes

With the ban of some synthetic companiesColoring has renewed people\'s interest in natural coloring Most natural colorings are environmentally friendly, biodegradable and have minimal toxicity. Synthetic dyes are made from petroleumChemical charcoal compounds. These resources are now being quickly depleted. In this regard, the creation of natural dyes is also beneficial for environmental protection. Although natural dyes cannot fully replace synthetic dyes due to their numerous deficiencies, they are used as partial substitutes or complements to synthetic dyes.

The chemical structure of natural colors is still unknown, and the extraction process is also quite inefficient. Therefore, research and development are required for its extraction and use, especially for the full use of plant leaves, flowers, fruits and rhizomes, as well as the use of other industrial waster extraction of natural colors. Natural dyes with high production and performance are expected to be generated through genetic engineering with the advance of biotechnology. The properties and structures of natural dyes are This is poorly understood and requires further research.

Substitute dyes for banned dyes

Many synthetic dyes have been bannedDue to the gradual improvement of ecological textile standards such as the Eeo-Tex Standard 100, dye manufacturers have in recent years developed a variety of synthetic dyes that meet ecological requirements. Other dyes will be developed in the future, as will dyeing processes.

Dyeing with high fixation or high uptake dyes

One of the most serious environmental problems in dyeing is dye pollution in the dye waste water. The development and use of dyes with high rates of dye absorption or fixation canFe significantly reduce in the waste water while improving the dye utilization. Various reactive, disperse and cationic dyes with high fixation rates have been developed at present, which minimize residual colors in the waste water as well as the water consumption for washing after drying and the amount of dyes produced in waste water.

Dying with high-fast dyes

The color fastness is strongly related to the ecological criteria of dyed fabrics. The color fastness of textiles can be verified using a color fastness tester. Some water-soluble dyes that have been used in the past, such as B. direct dyes for dyeing cellulose fibers, acid dyes for dyeing wool and silk, etc., have poor wet fastness. Such dyes not only pollute the environment quality of the textiles, but the dye waste water is difficult to filter. Such dyes are increasingly being used in favor of dyes with high color fastness, such as tom example reactive dyes with high wet fastness.

Previously dispersed dyes were mainly used for dyeing synthetic and acetate fibers. Due to the low solubility of disperse dyes, the wet fastness is good and the waste water can be filtered very well. Recently, disperse dyes for dyeing wool and silk fabrics have been studied and developed for years and are particularly useful for dyeing mixed fabrics of these fibers and synthetic fibers. The increased use of such dyes is also helping to promote “green” dyeing methods.

One-bath, one-step and short-dyeing

Mixed or interwoven textiles of different fibers are often dyed with more than two types of dyes, which is not not only requires a long process flow and is expensive, but also consumes a lot of energy, water and waste water. A bath dyeing research and development contribute to waste waterr and save energy. For example, one-bath dyeing with a dispersion/active effect is becoming increasingly popular and used more frequently.

Many dyes, such as e.g. e.g. dispersion/reactive dyeing, must be fixed in two phases. To fix the color, disperse dyes need to be steamed or baked at high temperatures, whereas reactive dyes need saturated steam. Appropriate additives can be added to fix the colour. They are steamed or baked in order at high temperatures to achieve one-step fixation. The single-stage drying technique can also achieve the goal of shortening the drying process, saving energy, saving water and increasing production efficiency, all of which are environmentally beneficial.

One - bath, single-stage and short-process processes also include bleaching and Dyeing, dyeing and finishing, and the process flow is shorter.

LowLiquor ratio, low feed solution dyeing

Dying with a low liquor ratio or low feed solution not only saves water, but also results in higher dye consumption and lower waste water emissions. For example, some of the modern slow flow and gas jet dyeing plants now dye with extremely small bath ratios and keep the materials with very small amounts in fast circulation with little dye runoff.

The use of a spray, foam and one-sided roller system can significantly lower the dyeing speed, which is especially useful for administering dye liquor or other chemicals in padder dyeing, such as lye for fixing the color of reactive dyes. This not only saves water and waste water, but also improves the fixation and saves steam or heat energy.

Likewise, the use of a high-efficiency roller mill and a vacuum suction system can reduce the effects, etc. verstrengthens padding and paint removal while saving energy, water and pollution.

Computer controlled dyeing

Use a computer to manage the dyeing process to achieve the optimal drying process. For example, at the moment the entire dyeing process is computer-optimized and controlled based on the dyeing characteristics of reactive dyes and the kinetic parameters of dyeing and fixing, which not only efficiently performs \"right first time\" dyeing, but also ensures good product quality and a short production cycle can be achieved. This method is also applicable to other types of dyes, such as disperse dyes and other dyeing methods.

Other drying methods such as waterless dyeing and low-temperature drying will be posted in the next blog.

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