Processes for Natural fibers: for cotton and rayon, web may be formed by air laying/wet laying or carding. The natural fibers are often hydroentangled to give them most fabric-like properties. While the end product obtained is excellent in properties, it is rendered expensive as compared to synthetic fibers. Cotton is most often mercerized and bleached to enhance its purity for a better acceptance in medical and hygiene areas. Cotton also poses difficulties in processing because of its high dust levels. Natural fibers find best applications in products like surgical gowns, swabs and drapes, gauze, disposable clothing, bandages, wound dressings etc. Cotton processing may include bonding techniques like resin bonding (for backing materials), thermal bonding of polyolefins +cotton blends and hydroentangling for highly absorbent products.

Processes for Synthetic Fibers: Synthetic fibers are most often blended with cotton/rayon. They are spunbonded and then bonded by any suitable bonding technique. Synthetic fibers may also be meltblown. For applications like filters, face masks etc, meltblown webs are preferred because of the small fiber diameters and excellent filtration efficiencies.

While synthetic fibers can be bonded by any technique effectively, it is mostly determined by their end use.

Post Processes

Post process for medical nonwovens is to give the product a suitable finish for its specific end use. The different types of finishes used in medical nonwovens are:

• Soil Release Agents: for bed linens, gowns and apparel which are designed for multiple usages. May also be used on curtains, blankets etc.
• Softeners: to make the webs feel soft against the skin. May be used for disposable undergarments, pillows, bed sheets etc.
• Water repellents: used for bed sheets for kids, barrier apparel etc.
• Flame Retardant Finishes: used for bed linens, curtains, apparel, lab coats etc.
• Antibacterial Finish: very commonly applied to gauzes, dressings and sutures. The most popular one is silver nanocrystal finish.
• Resin and Hand Builders: used for apparel, gowns, bed linens etc.

Conclusion

Medical textile market is totally saturated with nonwoven products today. Nonwovens, because of their easily modifiable properties and excellent performance have become indispensable in this field. Medical and Hygiene sectors combined together consume more than 90% of the total nonwoven production in US (Source: INDA). On the other hand, in developing countries of Asia, Africa and South America, demand for medical nonwoven is increasing significantly as a result of a fast-growing, increasingly urbanized, young, health-conscious population. In future, the demand of nonwovens in medical field is expected to grow steadily.