In the post-textile finishing process, low-refractive index resin is usually used to deepen the fabric, that is, the surface of the dark fabric is covered with a layer of low-refractive index resin, which reduces the amount of light reflection on the surface of the fabric, thereby increasing the apparent color depth of the fabric. Commonly used deepening finishing agents include fluorine resin, silicone resin, polyurethane resin, polyacrylic resin and so on. Although the polyacrylate type deepening agent can make the fabric achieve the effect of deepening, the fabric feels hard after finishing, and the subsequent soft treatment is still needed, and the operation is complicated. The cost of organic fluorine is relatively high, and there are environmental problems. Silicone not only has a low refractive index, can improve the absorption of the dye to the incident light to play a deepening role, but also can make the fabric with excellent soft feel, both energy saving and environmental protection, but also have the effect of deepening, so it can save dyes and reduce costs.

In order to explore the factors affecting the deepening performance of amino silicone oil, the amino silicone oil emulsions with different ammonia values and viscosity were synthesized by using different amino siloxane coupling agents and hydroxy-terminated polysiloxane oligomers as raw materials, and were applied to the deepening finishing of vulcanized black cotton fabrics. The results show that HD-121 coupling agent with dimethyl tertiary amine has better deepening performance, and the smaller the ammonia value, the larger the viscosity, the better the deepening effect. The effects of depth enhancer concentration, setting temperature and time on depth enhancer effect were investigated by single factor application test. The optimal finishing process is as follows: the mass concentration of deepening agent is 40 ~ 60 g /L, the setting temperature is 170 ~ 180 ℃, the setting time is 90 s, and the deepening rate is close to 50%. Sem characterization and silicon element analysis were performed on the fabric before and after treatment, and it was found that the silicon mass fraction on the fabric decreased from 1.2% to 0.5%, resulting in a decrease in the darkening effect.