The first method: mix high hardness silicone rubber and low hardness silicone rubber. For example, after mixing 20 hardness silicone rubber and 10 hardness silicone rubber, the hardness of silicone rubber will be about 15 Shore A; When using this mixing method, it should be noted that the condensation type can not be mixed with the addition molding, otherwise it will cause non curing.

The second method: we can use silicone oil to reduce the hardness of silicone rubber. Generally, adding 1% silicone oil will reduce the hardness of silicone rubber by about 0.9 ~ 1.1 degrees; Adding 10% silicone oil will reduce the hardness of silicone rubber by about 5 degrees. However, in practice, if the added silicone oil ratio is too high, the molecular weight of silicone rubber will be damaged, and the tear resistance and tensile strength will deteriorate accordingly, which will affect the service life of silicone rubber mold. In addition, too large the added silicone oil ratio will also lead to the easy deformation of silicone rubber mold. Therefore, we suggest: generally, the ratio of silicone rubber to silicone oil should not exceed 5%, and try to add silicone oil with higher viscosity. If more than 5% silicone oil is added, please try a small amount first to determine whether the mold can be used.