How does the Super Soft Hot Air Hydrophilic Non-woven Fabric process affect the bonding strength between fibers and the overall performance?

The production process of Super Soft Hot Air Hydrophilic Non-woven Fabric has a crucial impact on the bonding strength between its fibers and the overall performance. Hot air bonding process is one of the core technologies for the production of this non-woven fabric. By controlling key parameters such as temperature, pressure, and time, it can significantly affect the bonding method of the fibers and the performance of the final product. The following is a detailed analysis:

1. The basic principle of hot air bonding process
Hot air bonding is a process that uses hot air to heat the fiber surface to partially melt and bond to each other. The specific process is as follows:
Heating stage: Hot air passes through the fiber web to make the fiber surface reach the melting point or softening point.
Bonding stage: After the fiber surface melts, it forms a physical bond with other fibers during the cooling process.
Cooling stage: The fibers re-solidify to form a stable three-dimensional network structure.
The key to this process is how to accurately control the heating and cooling processes to ensure that the bonding strength between the fibers is moderate while retaining the softness and functionality required for non-woven fabrics.

2. Effect of hot air process on fiber bonding strength
(1) Temperature control
Temperature is too high:
Excessive melting of fibers may cause the fiber diameter to decrease or even break, thereby reducing the overall strength of the nonwoven fabric.
Excessive temperature may also destroy the chemical structure of the fiber, affecting its hydrophilicity or other functional properties.
Temperature is too low:
The fiber surface cannot be fully melted, resulting in insufficient bonding strength and easy delamination or tearing.
Optimizing temperature: It is necessary to select a suitable heating temperature based on the melting point of the fiber material (such as polypropylene, polyester or viscose fiber) to ensure that the fiber surface is moderately melted without damaging the internal structure.
(2) Pressure control
Excessive pressure:
It may cause excessive compression of the fiber, increase the density of the nonwoven fabric, and reduce its softness and breathability.
Excessive pressure may also cause the fiber to deform or break, affecting the bonding strength.
Too little pressure:
The contact area between the fibers is insufficient, the bonding strength is weak, and the mechanical properties of the nonwoven fabric may be reduced.
Optimize pressure: By adjusting the pressure distribution of the pressure roller, ensure that there is enough contact area between the fibers while maintaining the fluffiness and softness of the non-woven fabric.

(3) Time control
Too long time: Fibers exposed to high temperatures for a long time may cause excessive degradation or aging, affecting the durability of the non-woven fabric.
Long-term heating may also increase energy consumption and reduce production efficiency.
Too short time: The fiber surface is not fully melted, and the bonding strength is insufficient, which may cause the non-woven fabric to be easily damaged during use.
Optimize time: It is necessary to find the best heating time based on the thermal sensitivity of the fiber and the production line speed to ensure that the fiber is fully bonded and the performance is stable.

3. The impact of hot air process on overall performance
(1) Softness
The temperature and pressure in the hot air bonding process directly affect the softness of the non-woven fabric:
Too high temperature or too high pressure may cause excessive compression of the fiber, making the non-woven fabric hard.
Optimizing process parameters (such as lower temperature and appropriate pressure) can retain the fluffy structure of the fiber, thereby improving softness.
Fiber selection: Using finer fibers (such as ultrafine fibers) can further enhance the softness of nonwoven fabrics.
(2) Water absorption and hydrophilicity
The treatment of the fiber surface by the hot air process will affect the hydrophilicity of the nonwoven fabric:
If the fiber surface is over-melted, the pores may be closed, reducing water absorption and air permeability.
Proper hot air treatment can retain the pore structure between fibers while enhancing hydrophilicity through hydrophilic finishing agents (such as surfactants).
Post-finishing process: The water absorption capacity of nonwoven fabrics can be further optimized by coating or impregnating hydrophilic coatings.
(3) Mechanical strength
The bonding strength between fibers directly determines the tensile strength and tear resistance of nonwoven fabrics:
Optimizing hot air process parameters can improve the bonding force between fibers, thereby enhancing the mechanical properties of nonwoven fabrics.
At the same time, the arrangement and density of fibers will also affect the overall strength. For example, a higher fiber density generally increases tensile strength but may sacrifice softness.
(4) Breathability
The pressure and temperature in the hot air process will affect the porosity and breathability of the nonwoven fabric:
Excessive pressure may cause pore closure and reduce breathability.
Appropriate process parameters can retain the gaps between fibers, thereby ensuring good breathability.

The hot air bonding process has a profound impact on the fiber bonding strength and overall performance of the ultra-soft hot air hydrophilic nonwoven fabric by controlling key parameters such as temperature, pressure and time. In addition, with the application of new materials and new equipment, there is still a lot of room for innovation in the hot air process.