The manufacturing process of silicone rubber mold is illustrated by taking Maitreya Buddha mold as an example.


(1) Select the opening at the bottom as the positioning part, turn the cavity and inject gypsum, its height is about 30mm higher than the bottom, and dig out the pits for later positioning.


(2) Paste silly putty. Paste a layer of rice paper on the surface of the utensils, and then evenly paste 5mm thick plasticine on the surface.


(3) plaster mold. In order to support and fix the RTV mold and prevent its elastic deformation, the plaster mold is first made outside the clay layer. Make the plaster image piece by piece according to its approximate parting surface. Pay attention to the positioning between the plaster molds. The plaster slurry is gypsum: water = 1:1.


(4) RTV molding die production. Cast the plaster in reverse order, remove the plasticine, clean it up, apply parting agent to the ware and plaster mold respectively, and then close the mold.


(5) At the same time, the components of RTV are proportionally weighed and fully stirred after mixing. In the process of agitation, RTV reacts with ethyl silicate under the action of the accelerator organotin to produce low molecular alcohol. When the silicone rubber is poured, pores are generated on the molding mold, so it is necessary to decompress and defoam, which is generally carried out in a closed container with a vacuum degree of 100mmHg and the time is about 5min.


(6) The silicone rubber with exhausted bubbles is injected into the cavity of the mold and cured at room temperature for about 24h.


(7) Take off the plaster mold and cut it with a razor according to the expected parting line;


(8) Carefully strip the silicone rubber from the utensives, remove the utensives, and then close the silicone rubber mold with the plaster mold as is, and the silicone rubber mold is completed.