Amine value is the most important performance indicator for amino silicone oil, representing the molar amount of amino groups per gram of the oil (typically measured in mmol/g). Standard industry products generally fall within the 0.1–1.2 range; the specific value directly determines the strength of the interaction between the auxiliary agent and the fibers, thereby influencing the fabric's final finish from multiple perspectives.

Directly Determines the Level of Fabric Softness and Smoothness
A higher amine value indicates a greater number of amino groups on the silicone oil molecule's side chains. This enhances the oil's ability to adsorb onto the active groups of the fiber surface, allowing for the formation of a more uniform and dense lubricating film that significantly reduces inter-fiber friction. High-amine-value products (around 0.6) impart an exceptionally fluffy and soft hand-feel to treated fabrics, making them the preferred choice for materials characterized by a soft, supple texture—such as pure cotton knits, acrylic blankets, and rayon. Conversely, low-amine-value products (below 0.2) exhibit weaker adsorption capabilities; they provide only a basic level of smoothness, with very limited improvement in overall softness.

Significantly Affects Fabric Yellowing and Color Shade
Primary amino groups within the amino silicone oil are the primary cause of high-temperature yellowing in light-colored fabrics. A higher amine value corresponds to a higher content of primary amino groups; consequently, after high-temperature heat setting (above 150°C), the fabric is more prone to yellowing and color shade shifts. Therefore, for the finishing of white fabrics, light-colored textiles, and silk, low-amine-value products (0.1–0.2) are typically selected. This approach minimizes the risk of yellowing and preserves the fabric's original, vibrant color while still providing a satisfactory basic hand-feel.

Balancing Fabric Elasticity and Wash Durability
Products with an amine value in the moderate 0.2–0.4 range ensure effective adsorption while enabling siloxane molecules to form a cross-linked film on the fiber surface that provides both lubrication and elasticity. Treated synthetic and bast-fiber fabrics acquire a comprehensive hand-feel characterized by both smoothness and resilience. Furthermore, the finish offers superior wash durability, maintaining its performance even after repeated laundering, making it ideal for applications requiring a premium hand-feel, such as wool blends and sportswear fabrics.