The Thirty-Second National Symposium On Dyeing And Finishing Of Knitted Fabrics "Special Topic On Dyeing And Finishing Technology"

From 5 to 7 November 2019, it was jointly sponsored by the national knitting science and Technology Information Center and the knitted Specialized Committee of China Textile Engineering Society. The Guangdong Textile Association, Shantou Chaonan printing and dyeing industry association and Shantou Chaoyang textile printing and dyeing Association jointly organized the "three technical cup thirty-second" (2019) National knitting dyeing and finishing symposium, which was successfully concluded in Guangdong city Shantou city.

The theme of this symposium is "science innovation and environmental protection and intelligent manufacturing". It attracted more than 300 elite people from all over the country. During the conference, more than 30 industry leaders, senior experts, professors and technicians from universities and colleges made special reports on relevant policies, research and development trends. This issue is a special topic of dyeing and finishing technology.

Research on new dyeing and finishing technology with new fiber, new design and new structure

Dong Qin Xia

General manager of Shenzhou International Holdings Limited

Analyze the performance characteristics of new fibers, design and arrange new yarn reasonably, study new fabric structure, and provide basis for developing new fabrics. Through new fiber development of new fabric cases, the method and practical application technology of dyeing and finishing technology and new process are given. It also puts forward the path of synergistic research and new development of new fibers, new weaving, new dyeing and finishing, new technology, new technology and new products from the source.

One

Properties and properties of new materials and new fibers

1. new functional materials of new materials: antibacterial fiber, flame retardant fiber, anti static conductive fiber, anti ultraviolet fiber, far-infrared fiber, electromagnetic shielding fiber, hydrophilic fiber, medical fiber, ion exchange fiber, nano functional fiber, ecological functional fiber.

2. special-shaped surface functional fibers: profiled surface functional fibers are various fibers with different cross-section shapes used in spinning forming. At present, there are dozens of special-shaped fibers. Over half of the polyester fiber, polyamide fiber and polyacrylonitrile fiber on the market are heteromorphic fibers.

3. hot new fibers: multi hole silk fiber, Villev Viloft thermal insulation fiber, nano deodorant fiber, silver zeolite antibacterial fiber, new antibacterial acrylic fiber, high comfort hollow micro porous fiber, different fineness cross section Yy fiber, new light storing optical fiber, magic color silk, N-63 absorbent fiber, N-48 absorbent fiber, two component thermal fiber.

4. recommended new fibers: GRS regeneration hollow, regenerated cross, regenerated fine denier, regenerated color, regenerated white fiber series, flame retardant polyester fiber, silver ion antibacterial polyester fiber, moisture absorption and sweat perspiration fiber, moisture absorption and sweat perspiration SecoTec nylon fiber, fast wear resistant nylon, super conductive viscose fiber, super hydrophobic nano fiber, alginate fiber Kaisoutan, Acetel acetate fiber

Two

New design and new structure to develop new fabrics

1. the new design of the spinning mill is mainly manifested in the innovation of spinning process, the compatibility of new fibers and existing fibers. The new design involves new technologies and technologies such as spinning technology, blending ratio and compatibility technology, carding technology, drawing and lapping technology, combing technology, coarse and fine yarn twisting, twisting and spinning methods. Therefore, starting from the source of designing new fiber spinning technology, we should take into consideration the rationality of weaving and dyeing and finishing technology.

2. the new design of the weaving factory: the emphasis is on the design of the new fabric structure. In the weaving and weaving of new yarns, the technical key of the weaving process is solved by giving priority to the design of a reasonable fabric structure according to the yarn properties. Simple double rib weft knitted fabric, rib stitch, single and double bead mesh structure can no longer meet the demand. We must break the routine and design and develop new fabric structure according to the performance characteristics of new fibers and new yarns. For example: sandwich structure, punctate Terry weft knitted double-sided weave structure, weave weft knitted fabric woven structure, thin weft weft knitted fabric structure.

Three

New production technology for dyeing and finishing

The development and application of new fibers, new materials and new yarns is both a new opportunity and a new challenge for dyeing and finishing industry. It also promotes the research and core technology research of dyeing and finishing technology and new technology. Whether all new fibers, new yarns and new fabrics can be accepted or recognized by the market, the function is obvious, and the added value of the products are all the results. All of them need to be processed into new fabric products by dyeing and finishing technology.

The formulation principles of dyeing and finishing process for new products: A. first analyzes the basic materials of new fibers and new materials as the basic process for pre processing, dyeing and finishing; B. is the key to master the new materials, functions, purposes, functions, advantages and disadvantages of functional fibers.

Textile biological dyeing technology

Gong Ji Xian

Associate professor of Tianjin University of Technology

One

Preparation of biomass pigments

1. biosynthesis

Eubiotic Red: the biological preparation of nano pigments, by the metabolism of microorganisms, the use of cell factories in the microbial cells from the beginning of pigment synthesis. The idea of preparing nano pigments by biosynthesis is proposed, that is, by controlling the mass transfer performance of cell membrane, extracellular nano pigment can be obtained, and the suspension of nano pigment composed of fermentation broth can be used to prepare dye solution. This method of directly producing dye solution from microbial fermentation broth improves the processing efficiency of biomass pigments and greatly reduces the cost of production and application of biomass pigments.

2. biotransformation

From indole glycoside to indigo: Blue saponin hydrolyzed in bluegrass, glycoside bond cleavage, indole was formed, indole ketone was oxidized and condensed to form indigo under alkaline conditions.

From agricultural waste to plant dyes: the natural compounds from agricultural wastes are used as raw materials to prepare environment-friendly biomass based dyestuffs and process ecological textiles through biotransformation, so as to realize the intensive processing of agricultural products and high value utilization of agricultural wastes. Polyphenols obtained from tea stems, tea leaves and pruned branches and leaves were used as precursors to prepare pigments.

Two

Dyeing of biomass pigments

1. biomimetic dyeing based on pH regulation

Dyeing of fat soluble pigments: cellulose, protein and polyester fibers have good dyeing effect, high color fastness and antibacterial properties.

Dyeing of water-soluble pigments:

Dyeing mechanism of cellulose dye with delta pigments

2. biological reduction dyeing of plant indigo

Saccharomyces cerevisiae reduction: after Saccharomyces cerevisiae cell culture 12h, the pH value of the culture medium was adjusted to 11, adding dye with a concentration of 2%, adding 12h to the fabric after biological reduction, dyeing it, and washing and drying after 4 times of dyeing and ventilation and oxidation. After dyeing 4D, the K/S of the fabric can reach 4.5. The color fastness of dyed fabric is 3 degrees dry and 3 wet.

Alcaligenes reduction: Alcaligenes culture 24h, add 2% of plant indigo to restore, 12h after adding fabric, bath than 1:50, 30 degrees constant temperature dyeing, every 12h remove oxidized 15-20min, dyed 3D and wash after washing. Under this technology, the maximum K/S of the fabric is 9, and the color fastness is 3 degree dry friction and 3 wet rub. The characteristic of the method is that no alkali agent is needed.

Prediction of crease risk of knitted fabrics

Ling Qun min

Hunan Institute of Engineering Professor

One

Industry background

Crease is an easy appearance defect of knitted fabric, especially elastic knitted fabric. If we know the high crease risk of the fabric to be processed beforehand, the factory will work out the technological plan to avoid the crease. The prediction of the crease risk of the new knitted fabric before processing is an urgent problem for printing and dyeing enterprises.

Two

Mechanism analysis of crease generation

Color mark: the local reflection rate of the fabric is broken down when the fabric is folded, resulting in the deeper color of the fabric.

Drum mark: for the crease of the drum. The drum marks can be seen under the lateral illumination (shade lamp) through the bulging shadow on the backlight.

Indentation: a concave feature of creases, usually appearing only when the color marks are particularly severe.

External cause: during dyeing, pure cotton rough cloth starts wetting from the water into the cylinder and completes to the dyeing process. Until the whole process of discharging the cylinder, the magnitude and duration of the folding pressure, the pressure and the swelling rate of fiber swelling occur at the same place of the fabric at the same time, the rate of fiber swelling.

Internal cause: cotton weft knitted fabric will become more compact due to swelling of cotton fibers. The transfer degree of the yarn segment under external force will be significantly reduced, and the transfer of line segments in the coil will become difficult.

Three

conclusion

1. the condition for porosity to reflect the degree of freedom of yarn transfer.

When the density is different, the linear correlation coefficient between porosity and crease risk score is R2. The linear correlation coefficient is more than 0.93. The main reason affecting porosity is that the weight and thickness data of the knitted fabric coil are the test data of the blank cloth. The weight and thickness of the blanks are greatly influenced by the yarn tension, the tension force, the amplitude of the pulling frame and the way of pulling. The porosity of the blank cloth after washing is reduced, and the weight and thickness data of the sample can be used to calculate the porosity, which can eliminate the influence of different traction state on the linear correlation between porosity and crease risk score. Same gauze

2. a crease risk prediction system based on porosity data

A method for predicting the crease risk of knitted fabrics can be established on the basis of confirming that the porosity of the washed water can be used to assess the risk of crease. A risk prediction system based on porosity data and applied to all kinds of cloth can be established. The automatic risk assessment model for crease risk can be established to achieve the risk early warning of the crease risk. On the basis of docking with the enterprise technology and technology system, the automatic output of the reasonable production process can be achieved. The low cost of the crease risk rating can be used to produce the conventional low cost processing flow, so as to avoid unnecessary special processing costs. For the cloth with high risk of scoring, a special processing flow can be produced to produce the creases. Based on unfilled coefficient

Correlation between basic dyeing research and factory lean management

Shen Jia Jia

Associate professor of Jiaxing University

One

One time sample rate

Key control points: raw material moisture regain; bath ratio precision control (moisture content after cotton wetting); dyeing temperature and time; adding auxiliaries and leveling dyeing and holding time; cooling methods and soaping, drying, cooling and other links. The inspection method is based on a hard color standard (for example, the ratio of red, yellow and orchid is close to 1:1:1), so that all the proofing personnel are required to make the proofing according to the regulations, and the color difference within the standard sample is less than 0.3. Fig. 1 is a comparison of sample consistency before and after proofing SOP in the laboratory of a workshop in our factory.

Two

Technological innovation

1. influencing factors of cationic dyeing

Dye compatibility value:

Temperature:

PH value:

The range of influence of different dyes is affected by the pH value. It is the key to find the best pH value when mixing. When the three dyes are in the proper range of pH value, the dyeing is guaranteed.

2. cationic dyes.

Three

Intelligent manufacturing

The advantages of digital matching: the cost of dyes will be reduced to a minimum, generally reduced by 10% to 30%; reduce the color of the light source, give the exact formula under different light sources, reduce the number of color matching, improve the proofing efficiency, predict the color change phenomenon, know the quality of the formula color in advance, and have the function of accurate color correction. The correction formula, the difference coefficient between the statistical sample and the production sample, the difference between the production machines, and so on, can improve the color rate, facilitate the digital archive management, and connect with the automatic weighing system, the sample dyeing machine and the online detection system.

Continuous dyeing process and practice of polyester woven warp knitted artificial leather base fabric

He Jiang Ping

Xi'an Polytechnic University Professor

In recent years, with the continuous development of the national economy and the reform of the national economic structure, energy conservation and emission reduction and low-carbon lifestyle have become the theme of the times of today's social development. There is an urgent desire and practical demand for energy-saving and environment-friendly dyes and auxiliaries, energy saving and emission reduction equipment and new clean production technology.

One

Continuous dyeing of polyester warp knitted artificial leather base fabric without water washing

The influence of dyeing working fluid composition on fabric performance index: this experiment screened and determined the components of dyeing working fluid. According to the new technological process and the requirements of physical and mechanical indexes such as dyeing properties and hand feel of dyed fabrics, the types of disperse dyes, thickening agents, dyestuffs, fixing agents, anti drift agents and softeners are determined. The above components constitute the basic components of dyeing working fluid, and the proportion of each component in dyeing working fluid is studied.

The best dyeing conditions were determined in the project group. The specific conditions were as follows:

Dip rolling: two dip two rolling, rolling ratio 70%.

Pre drying temperature and time: 110 degrees, 60 seconds.

Steaming temperature and time; 100-103 centigrade, 25 minutes.

Baking temperature and time: 210 centigrade, 60 seconds.

Two

Industrial production process

Three

Comparative analysis of economic indicators such as energy conservation and emission reduction

After production experiments, basic specifications and operating procedures of various specifications of fabrics were basically drawn up, and the total number of fabrics of various specifications and requirements reached 3258 tons per customer. After statistics and calculation, the new process is compared with traditional cylinder dyeing. The cost of production is about 1 million 630 thousand and 200 yuan, and the production cost per ton of cloth is 500.58 yuan. The performance indexes of all kinds of specifications fabrics meet the traditional cylinder dyeing performance indicators, and some performance indexes are better than traditional cylinder dyeing performance indicators.