At present, the development of new sizing technology is very much focused on two aspects. The first is to improve the quality of sizing, and the second is to save materials, reduce energy consumption, reduce emissions, and improve the production environment. High-pressure pulp is a way to achieve low-carbon production. Combining the idea of ​​“two high and one low†sizing, combined with the characteristics of the equipment in the production battle, the slurry concentration is appropriately reduced, and the appropriate grouting force is selected to obtain the cotton yarn. Evenly sizing. Practice has proved that this not only ensures the breaking strength and wear resistance of the yarn, but also the quality of the sizing is not affected; it not only achieves the purpose of reducing the amount of slurry, reducing the cost of the pulp, but also reduces the work of the post-dewatering process. The use of time and water resources, and the reduction of sewage discharge, all meet the requirements of ecological environment.
1 Denim sizing particularity
If you carefully analyze the sizing of the denim, you will find that although the warp yarn is made of pure cotton fiber, it is better to sizing, but after the warp is dyed, the fiber inside the fiber and the fiber have been partially hydrophobic. The dyeing performance of the yarn is worse than that of the white yarn; and the cotton fiber of the coarse yarn is generally thicker and shorter, and the original yarn has less elasticity and elongation. Due to the high tension of the weaving machine, we must ensure that the looms have high efficiency and the quality of the machine. The sizing of the denim must have some special characteristics.
1.1 Selection of pressure of the pressure roller
At present, in the experience and technical introduction of the sizing industry, “the “two high and one low†sizing process has been widely recognized. “Two high and one low†refers to high concentration, grouting force and low slurry viscosity. The characteristic is that H{high slurry degree ensures the sizing rate, and the pressure of the high-pressure slurry roller and the low slurry viscosity are used to ensure the penetration of the slurry. Because of the good penetration between the fibers of the yarn, the strength and wear resistance of the warp yarn are Will be improved. However, for a sizing machine or a specific variety, how much is high concentration? How much is high pressure? How much is low viscosity? These parameters require multiple tests and practices. Experiments and production practices in many years Among them, different press forces are determined on different sizing machines because of the different weights and different diameters of the press rolls, the different speeds of the sizing machines, the different viscosities of the sizing machines, and the like.
1.2 slurry selection
(I) Environmental protection and cost. At present, the slurry of domestic burdock cloth is mainly various types of PVA, modified starch and acrylic pulp, plus 1: soft oil agent and so on. Some will also use some nano-based pastes. However, in terms of environmental performance, PVA has called for ban on the use of well-known degradation problems, and some materials have mixed environmental protection properties for polyester or nano-slurry. Therefore, considering the environmental protection and cost, the conventional modified starch and environmentally friendly polylaconic acid slurry are selected, and the formula is as simple as possible.
(2) Slurry. Due to the sizing characteristics of the aforementioned denim, the viscosity value (drip seconds) of the slurry should be both infiltrated and coated, and in the case of ensuring a certain viscosity (drip seconds), the slurry is strongly emphasized to have a strong adhesive force. This is because the slurry that penetrates into the inside of the yarn fiber must be strongly bonded to the fiber to increase the strength and wear resistance of the yarn; the slurry coated on the outer layer must have a great adhesive force, which can append the hairiness and reduce the warp. The falling, falling cotton, reducing the friction of the cloth surface. Only when the slurry has a strong adhesive force, it is possible to achieve the woven fabric weavability with a minimum of slurry, and further reduce the sizing rate. The reduction of sizing rate not only saves various costs, such as slurry, energy, desizing, sewage treatment, etc., but also lower sizing rate, can improve the quality of the machine, improve the hand feeling, facilitate sewing, shorten the washing time, etc. .
(3) Washing water desizing. The slurry on the denim is desizing (washed) before and after sewing. If the slurry is easy to desizing at the same sizing rate, it is more advantageous for the subsequent production process. In summary, after several times of slurry selection, formulation selection and production test, test comparison, sub-species promotion, etc., the optimized slurry formulation is conventional modified starch, M-5 textile slurry and oil. Agent.
2 production examples
Through a series of production practices, certain results have been achieved in sizing. Not only the sizing cost is reduced, but also the quality of the production environment and semi-finished products in the weaving workshop has been greatly improved, and unexpected effects have been obtained in desizing and mercerizing, which reduces the residual pulp rate of denim. The amount of desizing enzymes and the like is also greatly reduced.
2.1 12X12 98X65 59" 3/1 sizing of the right diagonal fabric
(1) Slurry formulation (Table 1)
Table 1 Slurry Formulation
(2) sizing process parameters (Table 2)
(3) Sizing quality indicators (Table 3)
(4) Weaving effect (Table 4)
(5) Effect analysis
1 new formula per barrel of pulp to reduce costs by about 50 yuan.
2 The weaving efficiency has increased from 94.3% to 96%, which has improved the production efficiency of the workshop to some extent.
3 Due to the decrease of the viscosity of the slurry, the fluidity and permeability are improved, which not only improves the strength of the warp yarn to a certain extent, but also reduces the splitting resistance, and also improves the good axial rate of the weaving shaft.
2.2 ring spinning bamboo 8 x ring spinning 10 78 X 59 59" 2 / 1 right oblique
Sizing of fabric
- Slurry formulation (Table 5)
- Sizing process parameters (Table 6)
- Weaving effect (Table 7)
- Breaking statistics during weaving (Table 8)
- Desizing process (Table 9)
- Gray fabric performance indicators (Table 10)
(7) Effect analysis
1 From the production effect of the weaving machine, the warp breaking is significantly reduced compared with the past, especially the sling to the heald, indicating that the wear resistance of the warp yarn is improved.
2 The slurry formulation no longer uses PVA, which not only reduces the pollution to the environment, but also reduces the cost per barrel of pulp by about 60 yuan.
3 Because the amount of starch is reduced during the sizing process, not only the amount of amylase is reduced, but also the production efficiency is greatly improved, and the production cost is further reduced.
4 Because of the reduction of the amount of starch in the sizing process, the sizing of the bad cloth is easy, the residual pulp rate is low, and the hand feel is soft, which is more in line with the needs of various garment factories.
3 results and discussion
(1) In the sizing process, reducing the solid content of the slurry by reducing the amount of starch, reducing the viscosity of the slurry to a certain extent, increasing the fluidity of the slurry, facilitating the penetration of the slurry, and achieving a good sizing effect. In the actual production process, the viscosity must be effectively controlled, not too low, otherwise it will not only damage the adhesion performance of the slurry, but also easily produce light pulp, causing the warp yarn to fluff, pilling and break in the weaving process.
(2) Due to the decrease in the viscosity of the slurry, an appropriate press force must be provided during the sizing process. The grouting force is too light, the surface of the warp yarn is thicker, and the dust in the weaving workshop will increase, which is not conducive to the production environment of the workshop. If the pulp force is too heavy, the sizing rate (lower) is difficult to ensure, which affects the production of the subsequent process (light pulp).
(3) Compared with the yarn-dyed industry, the denim industry mostly has coarse yarns, so the requirements for sizing are lower. As long as the daily production of the weaving workshop can be guaranteed, the sizing rate of the warp yarns can be further reduced.
(4) The amount of modified starch is reduced by the dry sizing process, the sizing rate is lowered, and the flexibility of the warp yarn is increased, thereby ensuring the softness of the cloth surface.
(5) The reduction of starch dosage not only reduces the sizing cost and environmental pollution, but also brings the convenience of denim after finishing (silk, desizing); but starch is the main slurry in the sizing formula. In order to be able to produce better, the performance of the starch must be stable. Otherwise, reducing the amount of starch will cause the sizing quality to fluctuate greatly.
References: slightly
Nitrogen Fertilizer,Liquid Fertilizer,Organic Liquid Fertilizer
Other Fertilizer And Chemicals,Pharmaceutical Machinery Co., Ltd. , http://www.nsfertilizers.com