STEP-UP™ Program White Paper INTRODUCTION In the past, Harper Corporation offered two types of anilox roll audits:
Both audit systems offered flexographers the ability to view the microscopic engravings of their anilox roll surfaces. However, in early-2002, Harper Corporation began investigating alternate anilox auditing methods with the goal of improving the process, getting more accurate results, and saving the customer time and money. This report describes the feasibility of the STEP-UP™ program that was developed to accomplish these tasks. Purpose The purpose of this study and report is to determine the feasibility of Harper’s new STEP-UP program, which combines the efficiency of a Harper Echochek audit with the digital accuracy of Harper’s ET audit. Scope This report, completed for Harper by a third party, describes the advantages, disadvantages, and a comparison between the Echochek audit and the ET audit. In pursuit of additional resources that might help improve the success of this study, several Harper Corporation experts were appointed to assist with this study in analyzing data, drawing conclusions and making recommendations. These individuals were asked to complete specified tasks, assist with research, and report on the technical challenges that are encountered in the current system. To determine the feasibility of the STEP-UP program, test parameters were established, performed and recorded. The data was then analyzed and proved that the new process works. BACKGROUND INFORMATION Echochek AuditThe Echochek is a small piece of foil used to make an impression of an anilox roll engraving. It consists of 2 mil mylar with a thin layer of polymer plastic coating. A coating of indium goes over the top to act as a reflective surface to light. Echochek evaluations can be performed on-site, allowing a technician to evaluate a customer's anilox rolls without removing them from the customer's facility.
Purpose of the Echochek Audit The primary purpose of the Echochek audit is to view the condition of the anilox engraving to determine:
Microscopes are used in Harper's technical laboratory to primarily evaluate results of the Echochek imprint, which is not viewable by the human eye. Under a microscope, the Echochek shows:
While the primary objective is to view cell engravings under a microscope, the Echochek also allows a technician to calculate cell volume within +/-10% accuracy. A technician examining the anilox cells measures the cell opening size, and the cell depth using the microscope. Therefore, measurement by microscope is subjective and not intended to represent absolute values. Human factors must be considered such as:
After measurement, the technician uses a mathematical formula to calculate the volume based on these measurements. The formula for determining volume is accurate for a very small range of cell shapes; therefore the accuracy of "calculated volumes" is approximate at best due to the human factors involved. Anilox volumes are measured in BCM's (Billions of Cubic Microns). These are very small measurements and every micron is critical. How big is a micron? A human hair is approximately 70 microns in diameter.
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The Echochek is placed on the anilox roll and pressed into the surface. The foil takes the shape of the engraving and can easily be sent to Harper's technical laboratory to be manually examined and photographed under a microscope. Echocheks are very small and easy to use. They provide us with a practical tool to determine anilox engraving information without taking highly sophisticated, and expensive instrumentation into the customer's facility or shipping the rolls to the anilox manufacturers facility. However, the limits of the use of the Echochek should be understood. 
