In coating production or application, adding defoamers is a common method to eliminate bubbles, but improper use may lead to cratering defects. Chemi Tech, a specialized brand in defoamer technology, offers the following solutions:
1. Compatibility Optimization
Cratering often results from poor compatibility between defoamer and coating. Use Chemi Tech’s high-compatibility series (e.g., KM-200) and adjust dosage (typically 0.1%-0.5%) via small-scale tests to avoid excessive surface tension disruption.
2. Process Parameter Control
High-speed dispersion (800-1200 rpm) can entrap air. Maintain temperature at 25-35°C and add Chemi Tech defoamers slowly during the mixing phase to prevent localized over-concentration.
3. Substrate Pretreatment
Residual oils or mold release agents worsen cratering.
4. Formulation Synergy
Frequent cratering may indicate resin-additive mismatch.
5. Application Environment
High humidity (>80%) or temperature fluctuations can cause defoamer migration. Apply coatings in controlled environments (20-25°C, 50-70% RH) with spray pressure at 0.3-0.5 MPa for optimal atomization.
These measures effectively address cratering caused by Chemi Tech defoamer misuse. For further assistance, contact the technical team for customized diagnostics.