Injection molding is the most common processing method for plastic products. In the mass production of household appliance shells, plastic toys, automotive interior components, electronic shells, and plastic parts for daily use, mold sticking has always been a frequent pain point in the industry. After the molten resin cools and solidifies, it tightly adheres to the mold cavity. Forced demolding is very likely to cause surface scratches, missing corners, and cracks on the product. A large number of defective products directly increase raw material loss, and frequent machine stops for mold cleaning also seriously reduce the production line's operating rate. Demolding silicone oil, with its extremely low surface energy, forms a protective isolation film on the mold surface, becoming the mainstream solution in the plastic injection molding industry.
Traditional demolding methods are divided into various types. Some factories use oil-based demolding agents, which are prone to accumulation after spraying, causing oil stains and depressions on the product surface, and insufficient adhesion when spraying paint later, and shrinkage cavities. Powder-based demolding agents are likely to remain in the mold gaps and accumulate over time, affecting product accuracy. Demolding-specific organic silicone oil, after atomization spraying, can quickly spread on the surface layer of the mold cavity, forming a uniform, thin, and continuous silicon-based isolation film. The film has stable mechanical properties, high temperature resistance, and does not rapidly decompose when exposed to high-temperature molten plastic, effectively preventing the plastic melt from directly adhering to the metal mold. When the mold is opened, the product can be smoothly removed, maximizing the protection of the product's appearance integrity.
Demolding silicone oil has a wide variety of subcategories, including solvent-based, water-based, and solvent-free systems, suitable for different production environmental protection requirements. Water-based demolding silicone oil uses water as the dispersion medium, has extremely low VOC content, and no pungent odor, meeting the usage requirements of injection molding parks with strict environmental control, suitable for food contact-grade plastics and children's toys production; solvent-free high-concentration silicone oil has higher effective components and less spraying volume, suitable for large thick-walled plastic parts and high-viscosity engineering plastics injection molding. For high-gloss plastic shells and transparent PC products, low-extraction purified silicone oil is selected to minimize silicon migration and avoid fogging on the product surface, ensuring a high-gloss and transparent appearance.
In actual production control, the spraying process and coating amount are crucial. Excessive spraying of silicone oil will cause the silicone components to migrate to the plastic surface, hindering subsequent painting, electroplating, and bonding processes. Many high-end plastic processing factories use controllable migration-type demolding silicone oil, combined with standardized spraying equipment, to precisely control the thickness of the film layer, balancing demolding effect and compatibility with subsequent processing. In addition to single-time demolding, some extrusion and rotational molding processes can also use internal additive-type silicone oil, giving the plastic certain self-demolding performance, reducing the frequency of external demolding agent usage.
The domestic IOTA series injection demolding silicone oil covers the entire viscosity range and can be customized based on the plastic material, molding temperature, and product appearance requirements. With the popularization of automated injection molding production lines, unmanned workshops and high-speed continuous production have become trends, and the demand for stable and long-lasting demolding aids continues to expand. Many plastic manufacturers have reported that after reasonable use of specialized demolding silicone oil, the product defect rate has decreased by more than 30%, and the frequency of mold cleaning has significantly reduced. In the future, low-VOC, low-migration, and environmentally friendly demolding silicone oil will continue to help the injection molding industry improve quality and efficiency, promoting the continuous improvement of the production level of precision plastic products.