When you select a mould release agent, you’ll find an abundance of high-quality options available from brands like Millers and Morris. As a result, determining the best product for your application can sometimes feel overwhelming.
By considering key factors and paying attention to specific requirements, the good news is that you can streamline and simplify the process. Here, we provide a detailed guide on what to consider when choosing a mould release agent.
Material compatibility
Considering the materials involved is the best place to begin. This includes the material that the mould is made of, but also the material being moulded.
Many types of mould release oils are designed for use with a specific moulding material. A common best practice is to utilise silicone-based agents for non-silicone moulded products, and non-silicone solutions for silicon moulded materials. However, it is important to remember that silicone often leaves residue behind that can interfere with post-mould processing.
While you should always review the manufacturer’s recommendations to find materials advised for a release oil, there are also general guidelines to consider. For instance, when using plastic, ensure agents are hydrocarbon solvent-free products, and when using rubber, choose low-stick oils for a cleaner and easier release.
When working with composites, select an agent that won’t impact the composite mixture – and if you’re using polyurethane, make sure the oil can tolerate high temperatures.
Moulding process
The moulding process used makes a massive difference on the success and effectiveness of a mould release agent. Always consider the equipment and tools used to creating the finished product.
Compression moulding is an intensive process that needs a high-strength mould release oil that can cope with high pressure and heat levels. Injection moulding is a faster-paced process. As a result, it requires agents that can endure for many cycles and offer easy release.
Thermoforming needs mould release oils that will hold up well during heat formation, and extrusion only needs minimal release agents that prevent build up and provide smooth part removal.
Process conditions
Always choose a release agent that can tolerate the operating temperature, pressure, environmental humidity and other conditions involved in your selected moulding process – like mould surface contamination – as these can cause fluctuations. These inconsistencies can cause inferior product quality, decreased process efficiency and increased wear.
Release Performance
Select an agent that won’t interfere with secondary operations like painting, coating or bonding, especially if the part needs further finishing. A high-performance mould release oil can prevent unwanted moulding issues, resulting in higher release quality with decreased defective parts and improved overall production.
When selecting a release agent, also consider the desired part finish, like matte or gloss, as different oils are formulated to produce specific effects.
Environmental and safety
Regulatory standards are a critical consideration when ordering a mould release agent. Many moulding industries require rigid compliance, regarding any materials used across the entire moulding process. Always understand the HSE (Health and Safety Executive) compliance requirements of your specific application. For instance, NSF (National Sanitation Foundation)-certified or food grade products are crucial for both pharmaceutical and food sectors.
Application methods
You may have requirements on how mould release agents are to be applied. Although flexible processes sometimes let employees select a simpler application method like an aerosol, for faster moulding cycles, a semi-permanent release oil that lasts longer over multiple cycles may be required.
Mould geometry
Considering mould geometry is also crucial. For complex mould geometry, a high-performance solvent or water-based, low-viscosity spray that can access deep undercuts and recesses is best. Unlike more viscous oils and pastes that pool and hide fine details, spray formulas guarantee a thin and even coat is distributed, which replicates the mould’s intricate design faithfully.
Post-moulding operations
Consider the entire production process. Ensure you select an oil that won’t interfere with and secondary stages such as bonding, coating and painting. This is especially important when a part requires further finishing.
Cost and budget
Although a cheaper initial outlay can be tempting when working to a budget investment, a higher-quality mould release oil can pay off over time by increasing the lifespan of moulds and improving productivity.
Finally, remember that maintenance is vital to prolonging the active service life of a mould, and that the release agent plays a crucial role. In mould maintenance, the oil not only makes it easy to release moulded parts, but safeguards the mould from wear, damage and the build-up of residue.
