Insights
Practical guide to processing 2K casting resins
Achieve stable and reproducible casting results under realistic production conditions.
The guide covers typical sources of error, the correct handling of reaction heat, humidity, and batch sizes, as well as specific information on polyurethanes, epoxy resins, and silicones.
Practical guide to 2C casting resinsFAQ
ISO-ELEKTRA casting resins are used in the encapsulation of electronics and electrical components, as well as for construction, cable network systems, agricultural machinery, mechanical engineering, sensors and the automotive and further more the chemical industry. They are also used to manufacture electronic components.
All ISO-ELEKTRA casting resins comply with EU Directives 2011/65/EU („RoHS“) and 2015/863/EU („RoHS III“), and they are manufactured using only REACH compliant raw materials.
The processing time, also known as pot life, is a producer-specific specification and refers (according to VDE 0291) to the time during which approx. 100 g of mixed casting resin can be safely processed, i.e. cast. This time can vary depending on the product – from a few minutes to several hours. The processing time can be found in the technical data sheet for each product.
Adding catalysts can significantly reduce the processing time and can adjust it to your requirements. The ambient temperature also has a significant impact on processing time. Increasing the temperature increases reactivity and shortens the processing time. Self-heating usually occurs and reduces the pot life for larger quantities. A high energy input (heating) during the mixing process can also shorten the processing time.
In a dry, cool place, in their original, sealed containers. Direct sunlight and frost must be avoided.
Opened containers should be used promptly. Stir the casting resin before each use. Casting resins absorb moisture, so opening them too often can cause bubbles to form during the hardening process. Containers should always be stored with their lids tightly closed.
As a general rule, the resin and hardener should be mixed without introducing air, and stirred until a homogeneous mixture is obtained. The resin and hardener should be tempered to approximately 20-25°C and stirred before mixing. The shape of the spatula is important. Do not use screwdrivers or round sticks for mixing. Round shapes reduce the mixing effect. A flat, wide spatula works best. You can find comprehensive instructions under insights > practical guide to processing 2K casting resins.
Experience has shown that the following errors often occur:
1. Visible streaks: The components have not been mixed homogeneously. Superficial streaks often occur when the mixing container is emptied and scraped residual material containing unmixed material.
2. Uneven mixing: Areas with different hardnesses indicate off-ratio mixing. The casting resin is incompletely cured, resulting in soft areas and overly hard areas due to excess hardener.
3. Large Bubbles: In cases of severe mixing errors, areas with unmixed hardener can swell and form large bubbles when they react with humidity in the air.
4. Small Bubbles: If air is mixed in due to excessive stirring or lack of venting, small bubbles may form evenly throughout.
5. Fine, superficial bubbles: This is not due to a mixing error, but rather, excessive ambient humidity.
6. Particle/clump formation: This indicates that the casting resin was not stirred sufficiently before mixing with the hardener.
We have summarized additional information in the following document:
The differences between mixing errors are gradual and difficult to distinguish. If you have any questions, please feel free to contact our technical support team at Dr. Oliver Bartels.
Storage stability varies depending on the product and its packaging. It is generally between six and 24 months. Precise details are provided in the respective technical data sheet. These time frames only apply to unopened containers that are stored properly.
Each batch is tested individually in our in-house quality assurance (QA) laboratory. We check the chemical identity by spectroscopy, visually evaluate the product, and test the processing properties using rheology and measuring the curing speed. Only flawless goods leave the ISO-ELEKTRA factory.
We advise on polyurethane, liquid rubber, epoxy resin, and silicone casting resins, especially for industrial applications in the construction, electronics, and electrical engineering industries. Please contact us directly, and we will be happy to assist you.
The best thing to do is contact our technical sales team. After analyzing your needs, we will recommend a suitable resin or develop a new formulation specifically for your requirements, such as temperature resistance, flame retardancy, viscosity, and curing time.
We work in various fields, including electronics and electrical engineering.
After a technical consultation, we will send you free samples for testing purposes in your industrial applications. You will also receive application instructions and safety data. Formulation adjustments are possible.