The pretreatment of pure cotton or polyester / cotton fabric is mainly to remove impurities from cotton fibers, so that the fabric has good printing and dyeing processing performance. The conventional desizing, scouring, and bleaching processes are set for different impurities. However, it is found in production that the above processes are not specific. What is the situation? China Knitting Fair will explain for you.
Bleaching is to turn the textiles containing pigments into colorless textiles. Generally, oxidants are used for bleaching. Dyeing is to turn colorless textiles into colored ones, and dyes are usually used for dyeing. If pure white cotton is produced, the printing factory will do two bleaching, the first time is called semi-bleaching and the second time is called full-bleaching. If producing colored cotton cloth, the printing factory should first do half-bleaching, and then dye it.
Also note: bleaching oxidants, not whiteners. Bleaching and whitening work on different principles. The role of bleaching is to remove pigments; the principle of whitening is to radiate blue fluorescence to achieve the purpose of "covering yellow".
At the same time as desizing, the oil and wax in the raw cotton components also start to saponify, which has a certain scouring effect. During the scouring process, not only the grease, wax, pectin, ash, lignin, etc. in the cotton components are removed, the slurry is further removed, and some pigments can be removed.
In the bleaching process, hydrogen peroxide not only removes pigments, but also has a certain removal effect on residual slurry and some impurities.
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In the conventional process, caustic soda is used as desizing and scouring, while in the hydrogen peroxide bleaching process, caustic soda is only used to adjust the pH value of the bleaching solution.
Since the alkali is an activator of hydrogen peroxide, if the alkali concentration is increased, the hydrogen peroxide is decomposed to generate H00-, and at the same time the reaction speed is increased, resulting in a large amount of reactive power consumption of the hydrogen peroxide. More importantly, due to the excessive activation of hydrogen peroxide, the formation of H00 · radicals is promoted, which has certain damage to the fibers.
In addition, in the production of fabrics, water, equipment and other heavy metal ions such as Fe2 +, Cu2 +, etc. will inevitably cause the hydrogen peroxide to crack and decompose, causing chain reactions.
Therefore, in the one-bath method of withdrawal, cooking, and bleaching, the amount of hydrogen peroxide in the strong alkaline bath must be strictly controlled, and its stabilizer must meet three functions: ① stabilizing perhydroxyanion (HOO-); ② shielding heavy metal ions; Mass production of perhydroxy radicals (HOO ·).
In the conventional bleaching process (pH 10 to 11), the hydrogen peroxide is activated by alkali to form HOO-.
At this time, water glass, because of its polymer network structure, shields heavy metal ions, can adsorb Fe2 + and block HOO—, so that Fe2 + does not undergo a catalytic reaction, and at the same time inhibits the formation and decomposition of H00 · radicals. Water glass can also combine with Ca2 + and Mg2 + ions in the bleach solution to form highly dispersed magnesium silicate and calcium silicate colloids, which are adsorbed on the surface of the catalyst to make it lose its activity and thus stabilize it.
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If water glass is bleached in soft water, instead of stabilizing, it will accelerate the decomposition of hydrogen peroxide due to the increase in pH. However, when the Fe2 + content exceeds the adsorption capacity of water glass, the stabilization effect is weakened. For this reason, although water glass has a good stability effect and is cheap, it cannot meet the above functions in the one-bath method of strong alkali withdrawal, boiling, and bleaching. Therefore, it is unreasonable to use water glass as a stabilizer alone in the prescription. If water glass, magnesium sulfate, and complexing agent are mixed in a certain ratio, it can be suitable for one-bath method of boiling back, boiling, and bleaching.
In addition, the scouring agents and detergents used in the prescription must be resistant to alkali, have good permeability in the alkali bath, have the effects of emulsification, washing, solubilization, and dispersion, and have a high cloud point. If these quality indicators meet If it does not meet the requirements, it will also have a certain effect on the effect of the one-bath method of retreating, cooking, and bleaching. In short, as long as you choose the appropriate hydrogen peroxide stabilizer and scouring agent, penetrant, and control the process conditions, the excessive alkali in the strong alkali is properly resolved , Intensification, stability, etc., will certainly make withdrawal, cooking, bleaching one bath method to achieve the desired effect.
In addition: ① The amount of water glass is too much, and there is more residual hydrogen peroxide, which fails to give full play to the bleaching effect. ② Reduce the amount of water glass and increase the chelating stabilizer. ③ Caustic soda concentration can be appropriately increased, and the rolling rate can be increased. ④The steaming temperature can be increased to 105-110 ℃.
Source: Global Textile Network
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Underwear is a huge piece of cake, and each underwear business wants to get a piece of it. Therefore, each of them has made every effort to advertise it through traditional TV or discount sales at the counter of the mall. The so-called Eight Immortals cross the sea, each showing its magical powers. However, the layman looks lively and the layman looks at the doorway. From the perspective of Underwear Show, there are actually a lot of knowledge behind different marketing techniques. Taking women's sportswear brand Yvette as an example, this sports underwear rookie focuses on new media marketing routes. Recently, a set of videos about "women's sportsmen" and posters on the theme of "better life".
Women's sports: "big" has "big" difficulties
In recent years, with the improvement of living standards and the enhancement of fitness awareness, more and more women have appeared in gyms and sports fields. However, women who are keen on sports have added a layer of troubles that men don't have: how to soothe the jittering big white rabbits on the chest while strenuous exercise has always been a problem that bothers the girls. A study by the University of Portsmouth in the UK found that for every mile (1609 meters) a woman runs, her chest swings up and down 135 meters. This means that for every mile you run, your chest spans about 1/3 of the playground. Because women's chests do not have muscles, they are mainly composed of fat, breast and connective tissue. Vigorous swings will lengthen and tighten the ligament tissue for a long time, which will damage the elastic fiber tissue in the breast and cause sagging and sagging deformation. If the girl's chest is small and she is doing less intense exercise, the situation is fine; if the girl is big-breasted and doing a strenuous exercise like running and playing, then it feels uncomfortable.
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Because of this, sports underwear specializing in protecting women's chests has been favored by more and more women in recent years. Compared with Europe and the United States, sports underwear appeared much later in China, but in recent years it has been popularized rapidly with a geometric progression. According to the statistics of the General Administration of Sport of China, the number of people who exercise regularly in China in 2016 reached more than 430 million, and it is expected to exceed 500 million by 2025. Among them, the female population will account for 40%, and the total number will exceed 200 million. According to data from Frost & Sullivan, a global corporate growth consulting firm, China's sports underwear production value was 800 million yuan in 2014, while the US sports underwear industry scale was nearly $ 300 million. Considering that China is more than 6 times the size of the US population, the market potential of Chinese sports underwear is undoubtedly huge. Yvette, who specializes in the design and production of women's sportswear, Julia Liu, the president, once told reporters that Chinese women's concept of sports underwear is still very backward. . And among those who wear sports underwear, half of them wear appropriate underwear. "Obviously, the big head of the Chinese sports underwear market is still behind. Euromonitor International, a market research company, predicts that the sportswear market will grow at a double-digit percentage each year and will surpass the luxury market by 2020, with a total of about 280.8 billion yuan. This is undoubtedly a fertile market yet to be developed.
From the age point of view, the post-90s and post-00s newcomers are the mainstream consumer group of sports underwear. Relevant data show that this group accounts for about half of the total number of consumers. At the same time, new humans are mainstream users of the Internet and social media. In this case, Yvette Fante, a sports underwear brand, made the Internet and social media the main battlefield of marketing.
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The cake is big, but the tigers serve
Although the potential and development of China's sports underwear market is still behind, the market competition is also very fierce. It is not an exaggeration to describe this situation as "the cake is big and the tigers are around". What are these tigers?
For now, the women's sports underwear market is dominated by European and American brands. Although Chinese brands have a certain share, it is difficult to compete with international giants. European and American giants can be roughly divided into two categories. One is traditional sportswear brands, such as Nike and Adidas. They were originally professional sports equipment manufacturers, and sports underwear was a production line derived later. Because of this background, most of their products have sports attributes and less underwear attributes. Most of them choose different color combinations, and the psychological study of women's underwear is not in place. The second category is the opposite. They were originally women's underwear manufacturers, such as Aimer, Wacoal, Victoria's Secret, etc. Sports underwear is a branch derived from them. Their strength lies in understanding women's breasts, but not enough grasp of sports-Wacoal's sports underwear styles are limited, simple and moderate in strength; Aimer styles are slightly more, but the strength is mainly low strength, and the audience is narrow; Mi has always followed the sexy line, sports underwear is beautifully designed, but not so practical. Therefore, when these brands make sports underwear, they always give the feeling of "halfway home".
In contrast, Yvette, which has stood out in recent years and specializes in the production of women's sports underwear, has grown up. Since entering the Chinese market in 2014, more than a million consumers have become Yvette fans in just a few years. Although this number does not seem to be large in absolute terms, the relevant data shows that its average repurchase rate is as high as 40%. The high return rate indicates that Yvette has won consumer recognition, which means excellent quality and bright prospects.
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Stand out, what does Yvette rely on?
Of course, it is impossible to get a sufficient amount of cake in the sports underwear market served by Qunhuhuan without going through some polishing. At present, the industry giants are flexing their muscles and trying their best. Last April, Victoria's Secret, the maker of women's underwear, announced that it would cut off the swimwear business and develop sports underwear with a younger and more personalized style. Amazon, the global e-commerce leader, announced that it would sell its own brand on its US website. For women's underwear, Amazon also released recruitment notices to find professionals who are familiar with the sportswear field.Therefore, Amazon is considered to be committed to the production of sports underwear. Launched the Li Na women's fitness sportswear series, intended to use the popularity of tennis superstars to grab the domestic market.
Facing the threats of the giants, Yvette, a rookie, also took care of the house. In design, considering that Asian women's bodies are different from those in Europe and the United States, Yvette conforms to the Asian market and tailors Asian women to create sports underwear that meets the needs of Asian women. Because sports underwear requires a high degree of fit, general brands have only three categories of sizes S, M and L. Many consumers report that "fashion is uncomfortable, comfortable and unfashionable, comfortable and fashionable but not fit." In view of this, Yvette launched multi-size sports underwear, one of which is up to 67 sizes. This is like the test scores. Everyone scores excellent, good, and passing grades, and Yvette gives specific scores. The workload is much larger, but the physical and psychological fit with consumers has greatly improved.
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As an emerging brand, Yvette is also willing to invest heavily in marketing, and the marketing wrist has its own characteristics. In 2017, Yvette's marketing strategy was fully blossomed through self-media operations, event sponsorship, large-scale exhibitions, running groups and sports group sponsorship. At present, the company has sponsored the Shanghai Pudong International Women's Half Marathon and the women's pink girlfriends running in the happy running circle, and has planned to enter the gym and shopping mall channels. On December 15, 2016, Yvette unveiled the first offline experience store in Nanjing Deji Plaza, enabling online shopping and offline experience to promote each other. In addition to the Chinese market, Yvette's international strategy is also being further improved. Yvette, born in Europe, is also familiar with siege abroad. In 2017, the company has established German and Finnish branches in the European market; in Asia, the brand is also preparing to enter Japan, Taiwan, Hong Kong and Singapore.
Source: CDC
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