How to Choose the Right Hardness For Mold Silicone

- Jul 23, 2020-

When the hardness of the mold silicone is lower than 10 degrees, the tear strength of the silicone is low, the elongation is large, and the silicone products are easily deformed; when the hardness is higher than 50 degrees, the tear strength becomes worse, and the silicone products will become brittle and easy to break or break. Generally, when the hardness of silica gel is 20-40, tear strength and elongation are the best conditions. In addition, the lower the viscosity (the better the fluidity), the more beneficial it is for vacuuming to remove air bubbles, but at the same time the tearing strength will be worse and the number of re-molding will be reduced.


0 degree hardness mold silica gel is a super soft silica gel. It is a colorless and transparent liquid for addition molding. It has excellent electrical properties and chemical stability, water resistance, ozone resistance, weathering resistance, non-corrosion, physiological inertness, and non-toxicity. Odorless, low linear shrinkage, easy to operate, etc. Mostly used for chest pads, shoulder pads, artificial human dolls, etc. The silicone products made are resistant to washing, without bubbles, and will not break.


The 5-10 degree hardness silica gel is soft silica gel with low hardness, good fluidity, easy to infuse, and non-corrosive. It is very suitable for soap crafts with delicate and soft patterns. The soap molds made are not oily, deformed, and have a smooth and bright surface.


10 degree -25 degree hardness silica gel is recommended to be used for products with a size of 10-20 cm. It is suitable for copying product models with very fine patterns and performing injection mold operations. This mold opening method is easier to demold and will not damage the silicone mold. The product. It can be used to make candles, copy various handicraft models, etc., and can also be used for embossing (planting glue) of clothing signs. Condensation type and addition molding can be used for candle silicone. The crafted silicone candle can be quickly ignited and will continue to burn normally until the candle is burned out without oily burning.


25°-30°hardness silica gel is recommended to be used for products with a size of 30-50 cm. It is suitable to choose the brush mold opening method. Condensed silica gel can be used for the production of silicone molds such as plaster, cement, concrete, rapid prototyping, GRC European components, large cement components, imitation marble, artificial culture stone, etc.; added transparent silica gel can be used for injection molding, imitating diamonds, and making jewelry models Wait. E608 can be used for shoe mold making.


40°-50°hardness silica gel is recommended to use brush mold (split mold, three-dimensional mold, plane mold) operation mode, which is suitable for products with not very fine patterns;


50-60 degrees is high hardness silica gel, high tear resistance, high temperature resistance, water washing and stone grinding resistance, strong adhesion and good firmness, mostly for precision parts or fixtures.


If the customer is making small products with very fine patterns, you should use a slightly softer silica gel; if you are making larger products, you should use 32-35A° harder silica gel.