Silicone products factory in the production process, product molding and demoulding is a key step, such as the problem of molding difficult to release the mold is very serious, will seriously affect the production efficiency, then in the face of the problem of difficult release, how to solve? The following are several methods of molding difficult to release molds for reference.
1. Surface treatment of the mold
1). The molding mold of silicone products is washed in front of the oil compression molding machine, especially the new mold that has just been discharged must be sandblasted first.
2). Choose different washing sands for male and female molds.
3). The mold that has just been blasted sand must be heated to a sufficient temperature before discharging and molding, and the mold release agent must be sprayed before molding.
It is worth noting that the electroplating mold must not be sandblasted, including resin sandblasting.
2. Spray release agent treatment
In the molding of silicone products, silicone products do not stick to which side of the mold to spray the mold release agent, but sometimes it is not easy to stick.
Solution: Use a spray bottle or other clean water, hope that the product sticks where it will spray, spray it after spraying, and the product will obediently stick to the place where it wants to stick.
3. Adjustment of mold temperature
The product likes to stick to the lower half of the mold temperature, when the upper mold temperature is 175 ° C, the lower mold temperature is 165 ° C, the product is usually stuck to the lower mold when the mold is lifted.
4. Use mold release agent
The release agent of condensed silica gel is generally divided into internal release agent and external release agent.
The internal release agent is added in the silicone liquid before curing, by curing, the mold release agent molecules migrate to the interface to form a surface with poor binding force to release the mold, generally can be selected higher fatty acids and their metal salts, W / O type silicone oil emulsion, liquid polyisobutene, azo compounds, high-grade fatty alcohols, ester waxes and the like. The advantage of the internal release agent is that it is easy to use, and the disadvantage is that it will have a certain impact on the performance of the cured silicone.
The external release agent is applied to the surface of the mold, forming a thin film that separates the mold from the cured silicone. Generally can be divided into two categories: inorganic release agents and organic mold release agents. Inorganic release agents are simple, such as talc, clay, etc., and can be applied to the inside of the mold. The advantage is that it is cheap, the disadvantage is that there is dust pollution.
Organic release agents are mainly oily liquids, such as methyl silicone oil, petrolatum, industrial butter, liquid polyethylene glycol, liquid paraffin wax and so on. Applied to the surface of the mold can be deformed