November 5-7, 2007 Nashville, TN Processing System Optimization David Chinnis Sr. Digital Plates Specialist The Flint Group
2 Three Considerations Method Machine Money
3 Method What methods may increase productivity? Testing and Measuring Processing Performance
4 Wash Out Rate Performance Are my processor brushes optimized and consistent? Brushes that are not level can’t possibly create consistent floors without over processing to compensate for error!
5 How do I know? Check Brush Level - Incremental Processors 12” long plate x maximum processor width Expose header (2”), no back exposure required Process, dry 20 minutes Measure 12 areas across Shim or adjust brushes to achieve variation <.007” Batch Processors require an entire sheet to accurately measure flatness (<.015”)
6 Wash Out Rate Performance Is my processing time optimized for my relief depth? Does it make a difference?
7 The Method Four plates similar size (ex. 18” x 18”) Masking Sheet 6” smaller than plate (15” x 15”) Face expose ONLY
8 The Method Process plates at four set speeds/times Allow a brief dry down (20 MINUTES) Measure the results Select plate with an average overwash of 0.008” – 0.010” measured in the unexposed area Does it make a difference? You bet it does!
9 Test Design All plate material from same batch 1 back exposure time selected to produce relief from.023” -.026” (210 seconds based on prior testing) 3 washout rates with 5% solids and 35°C 250 mm/min (4.0 min) =.010” overwash 180 mm/min (5.6 min) =.020” overwash 120 mm/min (8.3 min) =.062” overwash (Washed to support) All plates dried for 90 65°C
10 Measurements Gauge measured on 100% solid and 1% process areas 8 individual measurements for each area at each exposure combination Entire study measured 448 solid and 448 screen readings at 3 washout rates, for a total of 2688 gauge readings
11 Comparison 448 gauge readings at 100% solid and 448 gauge readings at 1% measured at each washout rate and averaged
12 Gauge (in) Washout250 mm/min180 mm/min120 mm/min Solid % Range AVG Comparison
13 Results Decreasing wash rate causes longer dwell time in solvent 250 mm/min = 4.0 min wash 180 mm/min = 5.6 min wash (40% increase over recommended) 120 mm/min = 8.3 min wash (108% increase over recommended) Longer solvent dwell time causes more swelling, thereby extending the dry time
14 Plate Processing Summary
15 Machine - Incremental Processors
16 Solvent Wash Plates / 8 Hour Shift 20 Plates/8 hrs
17 Machine Solids Content Measuring Pump Tank Draw
18 Machine Controlled Brush Depth
19 Money Optimized Wash = Optimized Dry Optimized Solvent = Optimized Wash Optimized Brushes = Optimized Plate Optimized Plate = Optimized Production Time = Savings!
20 Solvent Solvent Reclaim Costs Example: sq ft/yr ( % solid area on plate Usage = 12,931 gal - but expected recovery = gal Plate = $10.08 square foot (0.07¢ sq in) Solvent = $15.00 gallon (1293 replacement) Operating and Disposal = 0.66¢/gal reclaimed on site Estimated Annual Cost $27930 or 0.47¢/sq. ft. (.0033 ¢) Total Plate cost ¢ sq in
November 5-7, 2007 Nashville, TN THANK YOU! David Chinnis Flint Group Printing Plates