...Quality is a partnership that requires adherence between client and vendor to work closely in order to achieve the desired result…
We have implemented and have been improving a printing workflow for consistently high, reproducible quality. The aim was to standardize production by defining a number of parameters and specific tolerances combined with fine calibration and continuous quality control. A consistent measurement system and uniform inking of the print run guarantees the constant high quality of the printed material. Aduprint’s print process complies with the PSO (Process Standard Offset) ISO 12647-2 standards in order to define references and tolerances.
The Process Standard Offset system printing is based on standardized colometric values. The system enables jobs to be printed on several presses without differences in quality.
Aduprint operates a fleet of single press machine type, reducing costs of acquisition and maintenance as well as high degree of specific staff knowledge and a potential in adjusting production strategy.
Dot gain is one of the most important criteria for quality colour reproduction. Aduprint provides dot gain management in two stages:
- Calibrating printing plates by linearization
Under normal circumstances a certain deviation occurs between the digital image and the printed sheets. By this process we ensure the image-setter producing a dot size on the plate corresponding on the dot size in the PDF data. The process of linearization takes place every 3 months by Heidelberg Druckmaschienen AG.
- Setting up and maintenance of characteristic curves
Aduprint has been adapting the RIP process so the dot size of the printed sheets match with the printed data. Based on test runs the actual values are measured in print with a spectrophotometer. ISO 12647-2 describes the target values in print. The difference between the target and actual values need to be calculated and adjusted prior to plate setting. The deviation is measured on the spectrum of the tonal value ranging from 0% to 100% showing a characteristic curve showing the tonal value deviations. Using this curve the CTP system is set by pre-reducing of tonal values. We have several curves valid for the specific combination of ink, paper, blanket and printing plate.
The Heidelberg measurement-system "Axis controll" enables us to measure and manage color deviations, densities and tonal values automatically. The information is obtained from the print control strips analysing deviations and providing appropriate corrections to ensure mathing quality. With help of the Axis control color measurement system we operate with a high level of automation of online color control of ink zones
Stored target values are compared with the color strips measurement results. It gives the adjustment necessary based on he differences calculated. It enables an effective quality assurence in terms of
- ink film thickness to be reached accorning to ISO 2846 between 0,7 ans 1,1 micrometers
- managing dot gain
- avoiding dot deformation such as doubling, slurring, smearing
Chromatic Sysnthesis with gray component Replacement
The system is our newest implementation, a special Heidelberg software that calculates color combinations. This aimes at using the process black to replace CMY components. This leads to a complementary color reduction and significant ink saveing effects.
Fast ink up with CIP data
An extra-tool performed at all Aduprint presses. Data from the prepress stage is used to preset ink zones and determine the amount of ink required. The aim is to reduce washup processes saving time and waste contributing enviromental goals too. The data from the prepress is downloaded via intranet to the press control station in order to automatic presetting of the ink zone profiles.Taking into consideration the materlial printed and the ink being used the system enables us maximum utilization of press capacity. This reduces manual adjustment time.
Aduprint particularly performs besides the standardised color management system following checklist during operation.
- Assuring sharp contours,
- Monitoring register accurancy,
- Detecting and avoiding printing hickeys,
- Defining scratches
- Indentifying color flucuations continously
- compering the result with standard target values
- creating and adjusting printing characteristics