Integrated Lane Measurement for Adhesives and Medical Product Active Ingredients

Integrated Lane Measurement for Adhesives and Medical Product Active Ingredients

Greg Brown
Process Sensors

Many products in the Print and Packaging Industry are manufactured in discrete coated lanes across the web instead of full web coverage. This can be done for ease of slitting, reduction of coating costs, and tighter control of application materials. Manufacturers of pressure sensitive adhesive products such as transdermal patches and other drug delivery technologies need accurate measurement of coating applied, quality control and data archiving to meet governmental regulations. Similarly, label, tape and specialty film manufacturers that coat lanes also need accurate on-line measurement for control and data archiving. Traditional Lane Measurement across the web provides fixed point lane measurement. Combining these discrete lane measurements into a Cross-Direction (CD) Web Profile allows a clearer picture of coating uniformity across the web and in the Machine-Direction (MD) by eliminating the uncoated product in the profile display. Near Infrared (NIR) reflectance and transmittance analyzers provide accurate measurement of these adhesive lanes. The transmitters are mounted on sealed scanning traverses and output data to both a large profile display color coded with Green (Product in Spec), Yellow (Alert) and Red (Alarm Condition) lane zone measurements and to a Programmable Logic Controller (PLC) or Network. Sealing of the scanner protects the internals from contamination and insures proper operation. The Optical Measurement Area may be customized for very narrow lanes into a rectangular slot or small circular area. Ideally, just coating the desired lane and not the entire web reduces adhesive consumption and associated costs. High margin low web speed manufacturing as is common in medical and pharmaceutical applications, usually allows for this precise adhesive lane coating. Low margin high web speed manufacturing such as patterned plates sometimes suffer from web weave or coating head alignment issues and maintenance that increases scrap and lengthens production run times. A comparison of the on-line NIR measurements to Lab measurements including correlation coefficients and standard errors are outlined. Additionally, a comparison of cost reduction with precise lane coating to full web coverage for two different manufacturers with two differentconclusions and causes is outlined.