With the development and progress of non-woven technology, non woven is more and more widely used in the medical and health industry, and has great development potential and expansion space. Innovation and differentiated development will maintain its competitive advantage in the field of medical and health care. This paper introduces the main production equipment of medical non woven fabric at the present stage.
According to the drafting principle, spinning drafting equipment can be mainly divided into wide slit negative pressure drafting, wide slit positive pressure drafting and tube drafting. The style and characteristics of products made by wide slit negative pressure drafting process are better than those made by wide slit positive pressure drafting process. Wide slit negative pressure drafting system is a widely used spunbonded drafting process, and it is also the preferred system of SMS spunbonded production line. The prepared fiber has uniform thickness, comfortable hand feel, small longitudinal and transverse strength ratio, low energy consumption and low elongation at break. The non woven products are widely used in the field of medical and health care.
Netting technology includes wet netting and dry netting. Carding is an important process of dry netting process. Due to the continuous development and improvement of carding machine, non woven production line can achieve high speed and high output. At the same time, the application of carding machine feeding fiber layer self leveling device, air flow fiber box self leveling device, automatic control system and double closed-loop control system can automatically improve the uniformity of fiber web. The production of wet netting process is low, so it is gradually combined with Spunlaced technology. The raw materials are mainly natural fibers, and the products made are mainly washable materials. The use of spunlaced technology to remove the hairiness formed by fibers in wet netting can improve the softness and strength of materials, which is environmentally friendly and practical.
There are many kinds of reinforcement processes of fiber mesh, including mechanical reinforcement, chemical bonding reinforcement, thermal bonding reinforcement and so on. Acupuncture reinforcement in mechanical reinforcement includes pre needling, main needling, ring needling and tubular needling. Spunlaced reinforcement technology is also developing rapidly. It does not damage fibers, has high product strength, low fuzzing rate and high moisture absorption; When adopting thermal bonding such as hot rolling reinforcement technology, the deflection deformation compensation of the roll of the hot rolling mill is good, which has a great impact on the physical and mechanical properties of the product and the speed of the production line.
The finishing equipment is to meet the functional requirements of medical non woven in the use process, endow nonwoven products with antibacterial, water-resistant, blood resistant, alcohol resistant, antistatic and other properties, so as to improve the added value of nonwoven products. Finishing equipment includes online system and offline system.
The online finishing system mainly includes liquid filling and drying equipment, which is a system configured between the hot rolling mill and the winding machine of the production line. It can make medical non woven fabric have hydrophilic, water repellent and other functions. At present, the mainstream model of liquid filling equipment is kiss roll. There are many forms of drying equipment, including hot air drying, infrared drying, circular mesh hot air penetration drying, etc. The first two kinds of drying equipment have low cost and are suitable for slower production lines. When the speed reaches 400m/min, the hot air drying equipment is worse than the infrared drying equipment in tension and width control, product feel, drying efficiency, energy loss and so on; Although the cost of the circular mesh hot air penetration drying equipment is high, it has high drying efficiency. Moreover, the operating cost and energy consumption are far lower than those of the first two processes. It can be made into products with fluffy, good touch and small width change.
The off-line finishing system is an independent production system, including unwinding, finishing agent preparation, filling, rolling, drying, winding and slitting equipment, which can realize the functions that medical nonwovens need to achieve at a low speed, such as flame retardance, antistatic, anti alcohol penetration, antibody liquid and blood penetration. The liquid filling method of the system usually adopts submerged immersion rolling, so the water content of the material is high, and the capacity of drying water consumption and finishing oil consumption are higher than those of the online processing system, which requires that the water drying capacity of the offline finishing system is strong. In addition to using electric energy, steam, fuel oil, gas and other energy sources can be selected after finishing the system.
At present, the processing technology of medical non woven has been relatively perfect. The high-yield production line after the outbreak of the epidemic will greatly improve the production capacity of China's medical and health products, save a lot of medical resources, make the connection between nonwoven technology and biomedicine more close, and play an increasingly important role in the medical and health industry.