Depth and width of cured lines in photopolymerizable ceramic suspensions

When a photopolymerizable ceramic suspension is illuminated, the cured region is characterized by the cure width and cure depth. The cure depth follows a semilogarithmic behavior with increasing energy dose, as expected for Beer–Lambert absorption, and is described by the depth sensitivity (Sd) and depth critical energy dose (Ed). The excess cure width, which is the cured width beyond the incident illumination width, is also found to increase with the logarithm of energy dose. This quasi-Beer–Lambert behavior can be described by a width sensitivity (Sw) and width critical energy dose (Ew). The semilogarithmic dose dependence is demonstrated for ceramic suspensions containing silica, mullite, alumina, and zircon powders. Broadening can be quantified by the broadening depth (Db), which is the cure depth at which broadening begins to occur. It is shown that the broadening depth decreases with the logarithm of the normalized refractive index contrast between the powder and monomer solution.