How to formulate coatings for in-can protection?
Last update on Jan 14, 2026
During shelf life, paints and coatings are vulnerable to microbial growth, viscosity drift, skinning, and unwanted reactions that compromise stability and performance. Additionally, sulfate-reducing bacteria can lead to a bad smell resulting from production of H2S. This is where in-can protection comes in. In-can preservation ensures the durability of paints and aqueous mixtures. It protects against microbes such as bacteria, yeast, and fungi, which can contaminate the formulation during production, storage, transportation, and use.
Finer requirements and strategies
To ensure robust in-can protection, formulators must address two critical requirements:
- Prevent microbial activity: Stop bacterial and fungal growth that can spoil coatings in storage
- Prevent oxidation & hydrolysis: Protect base polymers, pigments, and additives from early chemical degradation
Related requirements that improve with main requirement
With the use of ingredients that help prevent spoilage during storage, additional benefits can be achieved in final coating performance:
- Reduced growth of fungi on dry film to help preserve the coated substrate
- Improved color stability and prevention of oxidation and hydrolysis of the dry film