Precise inspection of pharmaceutical and cosmetic packaging
Special inspection solutions for cosmetic flacons were the origin of Dr Günther Inspections in Germany, followed by various customers in the pharmaceutical market. Mark Ziegler discusses the technical solutions that have led to the company’s market success in these two sectors
Certain technical specifications for pharmaceutic and cosmetic products are different to conventional products, like beer bottles or jars. In general, the requirements for inspection accuracy are much higher. High class flacons must not have cosmetic defects. “The packaging is a fundamental component of the brand perception by the consumer and not only among females” says Linda Günther, with a smile in her face. On the other hand, the drugs in pharmaceutical bottles can save lives and must be manufactured with absolute precision.
A different glass structure, such as a greater glass thickness, or special shapes mean that defect detection is significantly more challenging than with standard beer bottles, for example. Additionally, it is hard to create symmetrical ratios for camera images. Further required test criteria concern the measurement of the bottom height, which is important to ensure the break resistance. In addition, the image processing of the container bottom, especially bottom notch recognition, is another criterion. Both sectors have requirements that are different to the standard, where flexibility and precision are indispensable.
Multi-image illumination for high class cosmetics Recognition of the logo and engraving is essential today. Tilo Günther is proud of the complete solution package offered for this sector. “Smart lighting is a key component. For this reason, specific R&D investments have been made by the team. A special image processing module in the software makes even the smallest cosmetic defects visible. Checking washboards and folds of flacons is just as easy as checking for symmetry of the overall shape and the inner bottom contour.”
According to Mr Günther, with one of the company’s selfbuilt light sources, it is possible to inspect the article shoulder from above. “Shape deviations in the shoulder of cream jars, for example, are very hard to detect by standard camera inspections. With our custom-made solution, we have a precise detection for these defect types. The consistently good feedback shows us the high level of functionality in practice.”
Specific requirements for pharmaceutic products
The inner bore measurement for containers and ampoules is among the important requirements, as the filling nozzle always has to fit precisely into the ampoule. Günther R&D experts have developed an accurate camera system that replaces existing mechanical systems in the star wheel machine. Defective containers are identified without being destroyed, as sometimes happened with older mechanical systems that had to touch the item. The rejector behind the inspection unit removes the defect articles, preventing an accumulation of outside broken glass on the conveyor. “The camera system can also detect bore diameters that are too large, which was not possible with the previous mechanical measuring systems” Tilo Günther confirms. “Furthermore, it is also faster with up to 450 articles/min.”
Hygiene is extremely important for pharmaceutical bottles and an outer diameter dimension measuring of the mouth rim guarantees that the closure always fits. In this context, a precise detection of containers with an unfilled mouth ensures that the closure of the container or ampoule seals tightly. An additional difficulty for this kind of glass container is the surface inspection. Articles are often coated and have a milkylooking surface. The smart software of the company’s sidewall inspection machine can deal with these challanges.
In conclusion, Dr Friedrich Günther, founder of the company is very pleased with the equipment’s market success and the positive customer feedback generated from large international glass manufacturers. He is looking forward to realising the projects that are already in the company’s production planning process.
Published in Glass Worldwide in May/ June 2021