Abstract
Effect of pH change on the shell thickness of calcium carbonate hollow particles was investigated. Calcium carbonate hollow particles were synthesized at different pH change rates by Carbon dioxide bubbling into a solution. And influence of pH change rate on the shell thickness was estimated by observing SEM images of cross section of hollow particles. pH change curve could be divided into two stages, before and after the point where pH changes rapidly, and could express each stage with the approximated curve. Rate parameters of pH change rate were determined from these approximated curves, and the relation with shell thickness was investigated. As a result, it has become clear that thickness of hollow particles is expressible by the rate parameter of approximation curve corresponding to the first stage which is characterized as the process from start of bubbling to the point where shell is formed.
