Defects in Coating - Capping, Peeling, Cracking, & Streaking

Defects in Coating refer to imperfections like peeling, cracking, or capping that affect tablet appearance or functionality.
These result from formulation errors, equipment issues, or process deviations.
It compromises product quality, stability, and patient acceptability.
Several problems can occur during the process, affecting the tablet’s appearance, performance, and patient acceptability.

Capping: Partial or complete separation of the coating from the tablet.
Peeling: Large sections of coating detach, exposing the tablet.
Cracking: Visible cracks in the coating film, potentially affecting integrity.
Streaking: Uneven color distribution, resulting in visible streaks.
Mottling: Irregular coloration or blotches due to inconsistent spray or drying.
Pick-Up: Excess coating material adheres to non-tablet surfaces within the equipment.
Weight Variation: Inconsistent coating thickness leads to weight discrepancies.
Color Inconsistency: Variations in color intensity or hue across batches.

Inadequate Mixing: Poor distribution of coating solution.
Incorrect Solvent Evaporation: Excess moisture or incomplete drying.
Temperature Fluctuations: Overheating or insufficient heating affecting polymer properties.
High Humidity: Moisture affecting the drying process and coating adhesion.
Improper Equipment Parameters: Incorrect spray rates, air flow, or rotation speed.
Tablet Surface Issues: Rough or uneven tablet surfaces hinder uniform coating.
Excessive Coating Thickness: Leads to cracking or capping.