Those small rectangular blocks of color at the bottom of toothpaste tubes, often called “eye marks,” “color marks,” or technically “eye-mark sensors,” are not meant for consumers. They are used in the manufacturing process to guide sensors that control where the tube is cut and sealed during production. These marks ensure consistent sealing and trimming, resulting in uniformly packaged products.
Consistent placement of these marks is critical for efficient and high-speed automated manufacturing. Without them, the process would be considerably slower and more prone to errors, leading to potential leakage, inconsistent fill levels, and increased production costs. This automated process has become a standard in the industry, enabling large-scale production of toothpaste and other tube-packaged products.
