1. Definition of Volume Solids Content

Volume solids content (%) refers to the ratio of non-volatile components in the coating to the volume of liquid coating. This is a very important concept because, after the solvent in the liquid coating evaporates, the remaining solid components form the coating film on the surface of the substrate.

2. Calculation Method of Volume Solids Content

The calculation method used by international paint companies and most other coating manufacturers is based on laboratory conditions, following the guidelines in the "OCCA (Oil & Colour Chemists' Association)" for determining the solid content of coatings (calculated by volume). This method involves measuring the wet film thickness before drying and the dry film thickness after drying, using the following formula:

Volume solids content (%) = (Dry film thickness / Wet film thickness) × 100

3. Example Calculation

Taking a certain coating product as an example, with a dry film thickness of 300μm and a wet film thickness of 180μm, we can calculate the volume solids content (%) of the coating:

Volume solids content (%) = (300μm / 180μm) × 100 ≈ 60%

Conclusion: The volume solids content of this coating is estimated to be 60%.

4. Conclusion

Understanding the volume solids content of coatings is crucial for coating selection and application. It not only affects the cost-effectiveness of the coating but also impacts the performance and durability of the coating. By accurately calculating the volume solids content, users can better understand the composition of the coating and make more suitable coating decisions.