The main reason for this problem is that you do not handle the products or original molds well, then you should deal with the original mold or products carefully before molding. Such as for the products with a complicated pattern or a unsmoothed surface, you should polish and clean the products after which it will be molded ,then spray the release agent. Normally, the release agent can be Vaseline , detergent. liquid wax Etc. In practical process, you can bush different release agent according to different material. The second reason is that the operator pour the silicone into the mold when the mixture is mixed evenly, then the finish silicone mold will not cure and dry entirely..
you can find answers of some Frequently Asked Questions about silicone rubber on below.