Amino silicone oil, widely used in the textile and cosmetics industries, has an ammonia value that is a key indicator determining its performance. Many people mistakenly believe that "the higher the ammonia value, the better the effect", but this is actually a common misconception. The scientific definition of ammonia value is the amount of hydrochloric acid required to neutralize 1 gram of amino silicone oil sample, expressed in mmol/g, directly reflecting the content of amino groups in the silicone oil. Amino groups, as polar groups, serve as the "bridge" connecting the silicone oil with fibers and substrates. The amount of amino groups directly affects the final application effect.
Amino silicone oil with a low ammonia value (usually < 0.3 mmol/g) has a low amino content and weak bonding force with fibers, resulting in a softer and smoother silicone oil film, but poor durability, prone to peeling, and a feeling that is slightly "soft and flimsy". It is suitable for scenarios where softness requirements are not high and a sense of smoothness is emphasized, such as the finishing of light-colored polyester fabrics. An ammonia value in the middle range (0.3 - 0.6 mmol/g) is a golden zone that balances effect and stability. At this point, the amino content is moderate, allowing for strong bonding with fibers while not affecting softness due to excessive intermolecular interaction. The hand feels soft, full, and smooth, and is suitable for most conventional fabrics, such as cotton and knitted products.
Amino silicone oil with a high ammonia value (> 0.6 mmol/g) has a high amino density and strong adsorption force with fibers, giving the fabric a fluffy and elastic feel. However, excessive molecular interaction can lead to an increase in the rigidity of the silicone oil film, resulting in a feeling that is slightly hard and with a noticeable涩感 (rough sensation)， and prone to oxidation yellowing problems. It is especially not suitable for light-colored fabrics. Mastering the core correlation between ammonia value and effect can avoid selection errors and enable amino silicone oil to perform at its best.