1、 Structure and working principle of spray coating production line

A typical roll to roll non-woven fabric R2R automatic spraying processing system generally consists of several key components integrated: the unwinding and rewinding linkage system of the roll fabric, the ultrasonic spraying system, the drying system integrated with circuit and PLC control, the bracket and protective cover, and so on.

• Unwinding and rewinding system: composed of front and rear coil placement mechanisms, guide rollers/pressure rollers, and stepper motors. The roll fabric can be laid out in a single layer, providing stable and adjustable tension control to ensure that the non-woven fabric runs smoothly and smoothly in the spraying area, and finally rolled up into a cylindrical shape.

• Ultrasonic spraying system: Multiple ultrasonic nozzles can be integrated, and the number of nozzles can be selected according to the width of the non-woven fabric. They are arranged in a row and assembled on a movable module that can be linked up, down, left, and right to ensure full coverage of liquid atomization; Simultaneously equipped with a liquid precision metering and conveying system, providing coating liquid for each nozzle.

• Drying system: It can dry non-woven fabrics online to ensure that the solution on the non-woven fabric solidifies during winding.

• Control integration system: Reasonably allocate (set) the travel or pause time of non-woven fabric and the time required for ultrasonic atomization spraying and drying, and input it into the computer control system; Ensure that the surface coating effect of non-woven fabric meets functional requirements.

2、 Advantages of choosing ultrasonic spraying for roll to roll non-woven fabric

Compared with traditional immersion, roll coating, or ordinary spraying, ultrasonic spraying has demonstrated advantages in R2R production: it can accurately control the flow rate, almost no overspray, and can save up to 50% of expensive chemicals such as fluorides and antibacterial agents. Maintaining a porous structure and gently atomizing the liquid can prevent excessive liquid penetration, and fully maintain the fluffiness, breathability, and soft touch of the non-woven fabric. By adjusting the droplet size and spray speed, precise control from surface decoration to overall treatment can be achieved. An ultra-thin and uniform coating can be formed on the entire width and length of the coil, without dripping or stripes.

3、 Typical application scenarios

• Fabric for medical and hygiene products: disposable surgical gowns/protective clothing: sprayed with long-lasting antibacterial agents or water and blood repellent agents. Medical dressings: Spray medication (such as growth factors), antibacterial agents, or hydrophilic layers. Sanitary napkins/diapers: Spray super absorbent polymers (SAP), antibacterial agents, or skincare layers on specific areas.

• Filter material: Air filter: evenly sprayed with antibacterial agents, antiviral agents, or catalytic materials (such as photocatalysts). Liquid filter: Spray hydrophilic or hydrophobic modifiers to precisely control the wettability and separation efficiency of the filter material.

• Textiles in the field of new energy: battery separators (although mostly spunbond non-woven fabrics, the principles are the same): sprayed with ceramic particle slurry to enhance the heat resistance and safety of the separators.

• Non woven fabric for construction: sprayed with waterproof and flame-retardant coatings.

The successful application of ultrasonic spraying technology in the reprocessing of functional non-woven fabrics represents the trend of coating processing towards "smarter, more economical, and more environmentally friendly" direction. Through ultrasonic atomization spraying technology, precise and efficient deposition of functional coatings on complex porous substrates has been achieved, providing effective and referenceable processing methods and technical support for the development of various non-woven fabric products with different properties.