1. Pretreatment: Laying the foundation for softening effect
Fabric cleanliness control
Before use, ensure that the pH value of the fabric is between 5.5-7.5. Residual alkali will destroy the stability of silicone oil emulsion. For example, cotton fabric needs to be neutralized to pH=6.8 with glacial acetic acid after oxygen bleaching to avoid the reaction of amino silicone oil with alkaline substances to form precipitation.

Temperature adaptability adjustment
Set the pretreatment temperature according to the type of silicone oil: non-ionic products can be used at room temperature (25-30℃), while cationic products (such as amino-modified silicone oil) need to be heated to 40-50℃ to enhance molecular activity. Experiments show that the softness score of polyester fabric treated at 50℃ is 23% higher than that of normal temperature treatment.

Equipment cleaning and maintenance
After each batch of use, the rolling groove needs to be cleaned with 0.5% sodium hydroxide solution to prevent silicone oil residue from forming a film. A printing and dyeing factory failed to clean the equipment in time, resulting in white spot defects in subsequent batches, with direct economic losses exceeding 150,000 yuan.

2. Precise control of process parameters
Optimization of concentration ratio
The recommended concentration of general silicone oil is 15-25g/L, and high-count fabrics (such as cotton yarn above 60S) need to be increased to 30g/L. A Zhejiang company found through orthogonal experiments that when the silicone oil concentration is 22g/L and the rolling rate is 75%, the fabric bending stiffness reduction rate reaches a peak of 62%.

Baking condition matching
Amino silicone oil needs to be baked at 150-170℃ for 90-120 seconds. Insufficient temperature will lead to insufficient crosslinking. Use infrared thermometer for real-time monitoring to ensure that the surface temperature difference of the fabric is ≤3℃. A company's product qualification rate dropped by 18% due to a baking temperature fluctuation of ±5℃.

Coordination of vehicle speed and tension
During continuous roller dyeing, the vehicle speed should be controlled at 30-40m/min, and the overfeed rate should be set at 3%-5%. Too fast a speed will cause uneven penetration of silicone oil. After a knitting factory reduced the speed from 50m/min to 35m/min, the standard deviation of fabric softness dropped from 0.8 to 0.3.

3. Post-treatment and quality assurance
Anti-sticking treatment measures
After baking, cold water washing (water temperature ≤30℃) is required to remove unreacted silicone oil. Adding 0.5g/L of penetrant JFC can increase the cleaning efficiency by 30% and reduce the incidence of oil spots on the fabric.

Storage environment control
Silicone oil emulsion should be stored in an environment of 5-35℃ and avoid direct sunlight. It must be used up within 30 days after opening, otherwise 0.1% of Kasson preservatives must be added. A company's emulsion demulsification caused by improper storage resulted in the scrapping of 20 tons of products.

Effect verification method
The bending stiffness (B value) is tested using the KES-FB fabric style meter. The qualified standard is B≤0.08N·m²/kg for cotton fabrics and B≤0.12N·m²/kg for polyester fabrics. At the same time, a washability test is carried out, and the softness retention rate after 5 standard washes should be ≥80%.