Solution_Solution_Zhongshan Hongsheng Biotechnology Co., Ltd.，Hongsheng Biotechnology,Environmental protection

New technology for textile functional finishing

The use of high-tech finishing technologies to increase the functionality of textile fabrics to protect textiles from various adverse environmental effects, such as ultraviolet radiation, harsh weather, microorganisms or bacteria, high temperature, chemicals such as acids, alkalis, and mechanical wear, etc. The profit and high added value of international functional textiles are often realized through finishing. 一、Foam coating technology There have been new developments in foam coating technology recently. The latest research in India shows that the heat resistance of textile materials is mainly achieved by the large amount of air trapped in the porous structure. To improve the heat resistance of textiles coated with polyvinyl chloride (PVC) and polyurethane (PU), it is only necessary to add certain foaming agents to the coating formulation. The foaming agent is more effective than the PU coating. This is because the foaming agent forms a more effective closed air layer in the PVC coating, and the heat loss of the adjacent surface is reduced by 10%-15%. 二、Silicone finishing technology The best silicone coating can increase the tear resistance of the fabric by more than 50%. The silicone elastomer coating has high flexibility and low elastic modulus, allowing yarns to migrate and form yarn bundles when the fabric tears. The tearing strength of general fabrics is always lower than the tensile strength. However, when the coating is applied, the yarn can be moved on the tearing extension point, and two or more yarns can push each other to form a yarn bundle and significantly improve the tear resistance. The silicone coating can produce a water repellent effect, so that the textile will not absorb too much water, so as to prevent the wetting effect from increasing the weight. The silicone rubber layer can filter out most of the harmful ultraviolet rays in the sun, and has a soft hand feeling. Silicone coatings are now used in airbag fabrics, hot air balloons, paragliders, spinnakers, tents, sleeping bags, and many high-performance sports and leisure fabrics. 三、Waterproof and oil repellent finishing technology The surface of the lotus leaf is a regular micro-structured surface, which can prevent liquid droplets from wetting the surface. The microstructure allows air to be trapped between the droplet and the surface of the lotus leaf. The lotus leaf has a natural self-cleaning effect, which is super protective. The Northwest Textile Research Center in Germany is using the potential of pulsed UV lasers to try to mimic this surface. The fiber surface is subjected to photonic surface treatment with pulsed UV laser (excited state laser) to produce a regular micron-level structure. If modified in a gaseous or liquid active medium, photonic treatment can be carried out simultaneously with hydrophobic or oleophobic finishing. In the presence of perfluoro-4-methyl-2-pentene, it can bond with the terminal hydrophobic group by irradiation. Further research work is to improve the surface roughness of the modified fiber as much as possible and combine with appropriate hydrophobic/oleophobic groups to obtain super protective performance. This self-cleaning effect and the feature of low maintenance during use have great potential for application in high-tech fabrics. 四、Antibacterial finishing technology The existing antibacterial finishing has a wide range, and its basic mode of action includes: acting with cell membranes, acting in the process of metabolism or acting in the core material. Oxidants such as acetaldehyde, halogens, and peroxides first attack the cell membranes of microorganisms or penetrate the cytoplasm to act on their enzymes. Fatty alcohol acts as a coagulant to irreversibly denature the protein structure in microorganisms. Chitin is a cheap and easy-to-obtain antibacterial agent. The protonated amino groups in the gum can bind to the surface of negatively charged bacterial cells to inhibit bacteria. Other compounds, such as halides and isotriazine peroxides, are highly reactive as free radicals because they contain one free electron. Quaternary ammonium compounds, biguanamines, and glucosamine exhibit special polycationicity, porosity and absorption properties. When applied to textile fibers, these antimicrobial chemicals bind to the cell membrane of microorganisms, breaking the structure of the oleophobic polysaccharide, and ultimately leading to puncture of the cell membrane and cell rupture. The silver compound is used because its complexation can prevent the metabolism of microorganisms. However, silver is more effective against negative bacteria than positive bacteria, but less effective against fungi. 五、Anti-felting finishing of worsted fabric With the increasing awareness of environmental protection, the traditional chlorine-containing anti-felting finishing methods are being restricted and will be replaced by non-chlorine finishing processes. Non-chlorine oxidation method, plasma technolog

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What should I do if color spots and stains appear in reactive dyeing?

Reactive dyes have a very good solubility in water.Reactive dyes mainly rely on the sulfonic acid group on the dye molecule to dissolve in water. -Ethylsulfonyl sulfate is also a very good dissolving group In the aqueous solution, the sodium ion on the sulfoethylsulfone sulfate group undergoes hydration reaction, so that the dye becomes anion and dissolves in the water. The dyeing of reactive dyes is dyed to the fiber by the negative ion of the dye. The solubility of reactive dyes is more than 100 g/L, most of the dyes have a solubility of 200~400 g/L, and some dyes can even reach 450 g/L. However, during the dyeing process, the solubility of the dye will decrease due to various reasons (or even completely insoluble). When the solubility of the dye decreases, part of the dye will change from a single free anion to particles, due to the large charge repulsion between the particles. Decrease, the particles and particles will attract each other to produce agglomeration. This agglomeration firstly gathers the dye particles into agglomerates, then turns into agglomerates, and finally turns into flocs. Although the flocs are a kind of loose assembly, because of their There is an electric double layer formed by positive and negative charges around it. Generally, the shear force of the dye liquor is difficult to decompose it, and the flocs are easy to precipitate on the fabric, resulting in surface dyeing or staining. Once the dye has such agglomeration, the fastness of dyeing will be significantly reduced, and at the same time it will cause different degrees of stains, stains, and stains. For some dyes, the flocculation will further accelerate the assembly under the shear force of the dye solution, causing dehydration and salting out. Once salting out occurs, the dyed color will become extremely light, or even not dyed, even if it is dyed, there will be serious color stains and stains. Causes of dye agglomeration The main reason is the electrolyte. In the dyeing process, the main electrolyte is the dye accelerant (yuanming powder and salt). The dye accelerant contains sodium ions, and the equivalent number of sodium ions in the dye molecule is much lower than the dye accelerant. In the normal dyeing process, the concentration of the normal dye accelerant will not have much influence on the solubility of the dye in the dye bath. However, when the amount of dye accelerant increases, the concentration of sodium ions in the solution also increases accordingly. Excess sodium ions will inhibit the ionization of sodium ions on the dissolving group of the dye molecule, thereby reducing the solubility of the dye. When the concentration of the dye accelerating agent exceeds After 200 g/L, most dyes will undergo different degrees of aggregation. When the concentration of the dye accelerator exceeds 250 g/L, the degree of aggregation will increase. Aggregates and flocs are formed quickly. Some dyes with low solubility will be partially salted out, or even dehydrated. The anti-agglomeration and salt-out resistance properties of dyes with different molecular structures are also different. The lower the solubility, the anti-agglomeration and resistance The poorer the salting out performance. The solubility of the dye mainly depends on the number of sulfonic acid groups in the dye molecule and the number of β-ethylsulfone sulfates. At the same time, the greater the hydrophilicity of the dye molecule, the higher the solubility, the lower the hydrophilicity, and the solubility The lower (for example, the hydrophilicity of the dye with the azo structure is higher than the dye with the heterocyclic structure). In addition, the larger the molecular structure of the dye, the lower the solubility, and the smaller the molecular structure, the higher the solubility. Solubility of reactive dyes It can be roughly divided into four categories Class A, dyes containing diethylsulfone sulfate (i.e. vinylsulfone) and three-reactive groups (monochloros-triazine + divinylsulfone) have the highest solubility, such as Yuan Qing B, Navy Blue GG, Navy Blue RGB, Golden RNL and All reactive blacks made by mixing Yuanqing B, three-reaction group dyes such as ED type, Ciba s type, etc. The solubility of these dyes is mostly around 400 g liters. Class B, dyes containing heterobireactive groups (-chloros-triazine+vinylsulfone), such as yellow 3RS, red 3BS, red 6B, red GWF, RR three primary colors, RGB three primary colors, etc., and their solubility is 200-300 g The solubility of meta-ester is higher than that of para-ester. Class C: Navy blue that is also a heterobireactive group: BF, Navy blue 3GF, dark blue 2GFN, red RBN, red F2B, etc., due to less sulfonic acid groups or larger molecular weight, its solubility is also low, only 100~200 g/ Rise. Class D: Dyes with monovinylsulfone group and heterocyclic structure, with the lowest solubility, such as brilliant blue KN-R, turquoise blue G, bright yellow 4GL, violet 5R, blue BRF, brilliant ora

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Confirmation of textile color samples and solutions to common problems

Color sample confirmation 1. Self-evaluation of color samples Use gray cards to match colors. Level 4.5 is required between the original sample and the sample sample. When using a measuring and matching instrument for color matching, generally ∆E<1, taking into account the system error, the internal control standard ∆E<0.6, strive for a standard sample. For high requirements, hue ∆H and saturation ∆C should also be taken into consideration. To fully understand the heat sensitivity and photosensitivity of the dye. There are few photosensitive dyes, such as try not to use Cibacron Yellow CR-01, especially Cibacron Yellow C-2R. Most dyes have more or less heat sensitivity. Shihlin dyes are more prominent. Cold, hot, dry and wet have an impact on the shade. When proofing such dyes, consider the tendency of the dye to stabilize after the dye, and intentionally reverse it. Deviate a bit. For example, most dyes tend to be slightly darker to red light after they are stabilized, and when the color is slightly cold after printing, they should be slightly greenish light so that the color light is just equal to the original when it is stable. Dyes with severe photosensitivity and heat sensitivity are used as the main color proofing, which may cause large-scale production of color cloth stacking and printing, and even irreversible in severe cases, such as olive green R, yellow C-2R and other dyes. Therefore, such dyes cannot be used. Whether the prototype meets the customer's requirements, we must know how to make a sample for regular customers, and it is easy to match the customer's habits. Different regions have different color preferences. For example, European orders avoid red and can be slightly greenish. Different consumer groups of fabrics have different color and light bias. For example, children's clothing generally likes to be gorgeous; men's clothing should try to be neutral, with low color saturation and dark gray; women's clothing should be bright and so on. General customers require at least 3 prototypes, namely A, B, C samples, and sometimes 12 samples. Consider from the aspect of depth, light and shade, bright and bright, and color, so as to improve the accuracy of the first time. 2. Recognition of the sample When the customer's opinion differs from the actual situation, the light source should be considered and communicate with the customer. When the customer reports that most of the samples in a color palette are too dark, it should be considered that the customer may have a double-layer counterpart, especially for thin and transparent fabrics, which will become darker when stacked. Some large companies require 4 layers of color matching for thin and transparent woven fabrics and knitted fabrics. The conventional is a single-layer contrast. When the "light jumping" is serious, consider replacing the dye to improve the "light jumping". To understand the "metamer" performance of dyes, make full use of colorimeters to screen dyes. When the dyestuffs applied by our factory cannot meet the customer's "jumping light" requirement or the "jumping light" is ∆E<0.5, we should communicate with the customer to confirm the sample of our factory. When the confirmed sample is used as the reference sample, there is no "jumping". Light" problem. Never choose a dye formulation that is unstable in mass production to meet customer requirements. When directly producing samples for color matching, you should try to match the colors under various light sources, such as D65 natural light, fluorescent lamps, and do not have serious "jumping lights". If it is serious, please confirm before production. 3. Confirmation of production of large sample (head cylinder sample) The color and light requirements for the production of large samples should be strictly in accordance with the customer's approval opinions, and the original sample should be used as the basis to confirm the deviation. It is best to persuade the customer to use the confirmed sample as the basis to deviation from the original sample. Because the fabric specifications of the confirmed sample are consistent with the large sample, it is easy to see the sample, the dyes used are the same, and there is no "light jumping" phenomenon. Generally, the color light is between the two, the gray card reaches 4 or more, ∆E<1 (the internal control standard is generally ∆E<0.8), and customers will recognize it. The batch difference is controlled above level 4 of the gray card, the left, middle and right color difference is controlled above level 4 to 5, and the batch difference ∆E<1 (within 0.8 of the internal control). When selecting dyes, try to use dyes consistent with the sample prescription. Adjust the color and light, the newly added dyes may cause the phenomenon of "bounce light". When there is an obvious "bounce light" between the large sample and the confirmed sample, there will be the risk of rejection of the large product, which will bring economic loss and

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Common defects in denim warp dyeing and their prevention

Common defects in the dyeing of denim warp yarn are mainly colored files, streaks, chromatic aberrations in the edges, color aberrations in the head and tail (or fragment color aberration), stains, and tank aberrations. 1. Color file Color profile refers to the color difference between the latitude segments, which presents a straight strip of uneven color, which is also called horizontal profile. The probability of the ball being broken after dyeing and going around the guide roller is small. The dyeing and sizing are carried out separately, and the color file defect is few. Therefore, the color file defect mostly occurs in the dyeing of the dyeing and sizing machine. The main reason is that the dyeing process stops in the middle of the dyeing process, and the yarn fragments staying in the dyeing tank dyeing liquid absorb excessively, resulting in color stalls. Generally, if the parking time exceeds 30s, it will cause defects in the cloth surface.

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The influence of garment dyeing on zipper

In the process of garment dyeing, garments will be exposed to different pH dyes and auxiliary dyes according to different materials. In addition, the dyeing time of ready-made garments is relatively long, sometimes the whole process can take up to 7-8 hours. The zipper will produce great changes in this process, such as the following:

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Poor tearing strength

◆ Influencing factors of tearing strength ① Raw materials Different raw materials show obvious differences in the degree of resistance to external tearing and tensile forces. ② The organizational structure of the fabric

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Oxidative yellowing of denim garments

As a kind of casual clothing suitable for all ages, denim clothing is deeply loved by people. With the improvement of people’s living standards, consumers are no longer satisfied with the traditional heavy and rough denim clothing, hoping that denim clothing can be lighter, thinner and more comfortable. Demonstrate a unique taste. However, thin denim clothing is prone to product yellowing, which will seriously affect product quality. Yellowing is a phenomenon in which the surface of a material turns yellow under the single or combined effect of light, heat, oxygen, water, and chemical substances. The yellowing phenomenon is common in the production, storage, transportation and use of light-colored textiles. ◆ Classification of yellowing ① Ozone yellowing

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Denim ready-to-wear

Stretch denim fabrics refer to denim fabrics containing spandex, which are generally core-spun yarns or covered yarns centered on spandex. According to the physical and chemical properties of spandex, elastic denim products containing spandex cause loss of elasticity during the washing process. The spandex fiber is affected by external conditions, such as chemicals, humidity, heat, etc., and the fiber itself is damaged, causing breakage and losing elasticity. Recovery performance, the fabric cannot retract freely after being stretched, causing loss of elasticity. In the washing and dyeing process of denim products, once the loss of elasticity occurs due to the degradation of spandex, it is difficult to repair, so the loss of elasticity can only be controlled by preventive methods.

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Denim garments have a big residual smell

Consumers often find peculiar smells when buying denim clothing. There are generally two reasons for this phenomenon: one is that the odor of the black denim fabric itself is not removed in the subsequent washing process; the other is that the chemicals used in the washing process occur Chemical reaction, the peculiar smell remains on the clothing, among which the chlorine bleaching process and the high manganese treatment process are easy to produce the smell.

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