What Is The Non-woven Fabric Composite Process?

Nonwoven composite process is a process that combines nonwoven fabric with other materials (such as films, fabrics, functional layers, etc.) through physical or chemical methods to form new multilayer materials with a variety of properties. Its core is to break through the performance limitations of a single nonwoven cloth through the combination of materials to meet differentiated needs of waterproofing, breathability, antibacterial and high strength. The specific analysis is as follows:
1.Core values of composite processes
Performance complementarity
Nonwoven fabric itself has the advantages of light weight, good breathability and low cost, but also has the disadvantages of insufficient strength and poor waterproofness. The advantages of other materials can be superimposed by a composite process:
Waterproofing: Compound PE or TPU film make the material resistant to liquid penetration, suitable for use in medical protective clothing, surgical sheets, etc.
Breathability: The microporous membrane composite technology is used to allow water vapor to pass through while remaining waterproof and improving comfort to wear, often in tracksuits and medical dressings.
Function: Superimposed bamboo charcoal fiber, silver ion coating, give the material antibacterial, moisture absorption, deodorizing and other characteristics, meet the high standards in medical and home fields.
Cost optimization
By combining low-priced non-woven fabrics with high-priced functional films, performance can be improved while controlling costs. For example, the outer layer of medical protective clothing is made of waterproof film and the inner layer is made of a hydrophilic non-woven fabric, which ensures both protection and comfort at a lower cost than pure high-performance membrane materials.
2. Mainstream Composite Process Type
adhesive coating
Principle: Apply hot melt glue evenly on the surface of nonwoven cloth or film.
Strengths:
Homogenization: Fiber spraying technology such as American ITW DYNAFIBERTM can be used to control the diameter of the adhesive wire, eliminate the defects of the particle glue spots and increase the strength of the composite by more than 40%.
Ventilation: Using a non-contact spraying design, the colloidal barrier is reduced to the micropores, and the loss of air permeability is reduced to 20%-30%, down from the 40% in traditional processes.
Production efficiency: up to 900m / min production line speed, spray width can be adjusted from 4mm to 7000mm, suitable for large-scale production.
Usage: Medical protective clothing, surgical protective articles, industrial protective clothing, etc., have high requirements for breathability and waterproofing.
Laminating and laminating
Principle: Molten plastic (such as PE) is coated evenly on the surface of a non-woven cloth by a film attachment machine to form a film layer.
Strengths: Simple process, low cost, production speed of about 100m/min.
Constraints:
Poor air permeability: Not used in products that require breathability,such as medical masks.
Hard feel: After the film, the comfort of the material decreases, mainly for packaging materials, tablecloths and other scenes that do not require high flexibility.
Hot rolling and laminating
How it works: Nonwoven fabrics and films (such as PE) fuse between hot rollers through heat and pressure.
Advantages: The device has high compatibility and can be used in the existing text-messaging nonwoven production line.
Constraints:
Difficulties in temperature control: The melting point of non-woven cloth (polypropylene, melting point 165-173°C) and polyethylene film (melting point 120-130°C) are very different, and the temperature of hot rolling mill needs to be controlled accurately to avoid material damage.
High rate of air loss: It is easy to block micropore during hot rolling, and the rate of air loss can reach 30%-40%.
Purpose: Disposable surgical gowns, sheets and other medical supplies that do not require high air permeability.
Ultrasonic lamination
Principle: High frequency vibration is used to generate heat through friction between nonwoven cloth and thin film contact surface to achieve local welding.
Strengths:
Glue-free pollution: No adhesive required, environmentally friendly.
Precision: Realizable point, thread or pattern lamination for precision medical supplies (such as wound dressings).
Limitations: High equipment cost, slow production, mainly for small quantities of high-end products.
3. lamination process Selection Basis
Performance requirements
Medical field: For waterproofing, breathability and comfort, it's best to opt for a hot melt coating or ultrasonic lamination.
Industrial protection: Layered or hot rolling lamination can meet basic waterproofing requirements at a lower cost.
Home furnishings: Select according to product positioning. For example, if sheets need to be soft, choose hot melt laminate, or laminate the packaging materials.
Scale of production
Mass production: Hot melt adhesive coating and laminating processes high efficiency, suitable for mass production.
Small batch customization: Ultrasonic lamination is highly flexible and can quickly adjust the structure and position of composite materials.
Cost budget
Low-cost solution: Low Laminating process equipment investment and low cost of materials.
High-performance solutions: While the equipment cost of hot melt coating is high, it saves a lot of glue (up to more than 40% on glue of the same strength) and costs less in the long run.