Technical Information

Digital technologies are revolutionizing the printing industry. However, ink rooms are often overlooked when offset printing plants seek ways to improve quality, reduce costs, and increase productivity. This is a significant misunderstanding, as any standardization efforts in the printing shop are wasted if the offset inks are substandard.

With the right color matching software, ink formulation can be an integral part of a color workflow that shortens cycle times and increases profitability. A digital ink formulation workflow helps offset ink rooms streamline ink measurement and formulation steps, reduce waste, and improve sustainability and cost-effectiveness.

 

 

Digital Offset Ink Room Technology

Ensuring accurate ink color matching is crucial to meeting customer color quality and consistency requirements. Inks outside tolerances increase prepress preparation time waste, defect rates, and rework, and cause costly ink waste with difficult-to-use leftover ink. Implementing digital workflows in the ink room helps reduce the potential for errors and simplifies prepress processes.

 

Advantages of Digital Offset Ink Formulation Workflow

Implementing digital workflows in offset ink rooms offers numerous advantages, including saving time and money and improving overall color quality, including:

• Automated ink formulation and archiving
• Reduced ink drawdowns
• Maximize leftover ink to reduce inventory
• Quickly query saved recipes from data
• Printing operators can improve print quality without deep ink expertise
• Improved repeatability between batches and jobs
• Reduced press downtime
• Reduced print setup time

Color matching software provides a solid foundation for a successful digital ink workflow. xRite InkFormulation software supports the creation, saving, approval, and querying of recipes for offset, flexographic, gravure, and screen printing inks. It can even generate new recipes using leftover inks, improving process sustainability.

12 Steps to Digital Ink Color Matching

 

1. Incoming Ink Inspection

Inconsistencies can exist in CMYK process inks and spot color base inks. To ensure that purchased inks are consistent and qualified, an ink drawdown can be made, allowed to dry, and measured using a spectrophotometer.

 

2. Define Specifications

Printing jobs typically include color specifications. This specification is usually a Pantone reference, which everyone must use as a reference target and measurement condition. It is recommended to use digital specifications for ink formulation, as they do not fade or deteriorate, and the digital file contains ink type, printing process, and substrate data.

 

 

3. Define Target Color

There are three ways to define target colors: measure physical samples using a spectrophotometer; import digital color files (CxF) from customers or the InkFormulation software library; select colors from a digital color library. These measurements and digital files will include the spectral information of the target color, which will be used to calculate the L*a*b* values.

 

 

4. Measure the Printing Substrate

Substrate color is an important consideration when formulating offset inks, as it will show through and affect the final color. Measuring it with a spectrophotometer allows it to be taken into account in the offset ink formulation calculation.

 

5. Establish Ink Film Thickness

Formulations should typically be defined for and verified on the offset ink room proofing press, and then fine-tuned to a specific printing ink film thickness using the software.

 

6. Automatically Generate Ink Formulation

The InkFormulation software will calculate suggested formulations that achieve results within the specified tolerances, listing them according to metrics such as Delta E, number of components, and spectral deviation. Once a formulation is selected, it appears in the InkFormulation software user interface.

 

 

 

7. Ink Drawdown Production

Mix the offset inks according to the selected formulation in a certain proportion, and then make a drawdown. When using a digital workflow based on spectral values, most customers still need physical drawdowns because digital standards give strict tolerances and specifications. This helps significantly shorten cycle times. Once the offset ink is formulated, continue to check its color accuracy by comparing it to the target. Also, ensure that the proofing press settings are as close as possible to the target press type.

 

8. Measure Drawdowns

Measure the drawdown from three points using a spectrophotometer and calculate the average spectral measurement. InkFormulation will compare the drawdown measurement to the target color and then calculate the Delta E. If the formulation does not meet the specifications, the InkFormulation software can correct the formulation. Reformulate the ink and make a new drawdown if necessary. In practice, digital workflows require fewer drawdowns, significantly speeding up ink preparation.

 

 

9. Save Ink Formulation

Once the formulation is determined to meet tolerances, save the formulation so that accurate ink color and weight can always be formulated in the future. Depending on the target substrate, the same color may require multiple formulations. Spectral measurements during prepress and printing help ensure color consistency and meet customer requirements.

 

10. Evaluate Color Matching Results

Quality control software can quickly compare the formulation to the digital color reference in the software and perform pass/fail analysis. This data helps integrate color specifications and reporting information into the supply chain workflow, allowing for efficient monitoring of printing production and real-time ink correction to avoid color errors.

 

11. Correct Formulation to Form a Closed Loop

When the color measurements in the flexographic or gravure printing process do not meet the tolerances and the quality control software report indicates that existing formulations cannot meet the tolerances, the data for correcting the ink formulation can be sent to the InkFormulation software with a simple button operation. The ink room can make appropriate adjustments and quickly use the new formulation for quick and efficient correction.

InkFormulation software can integrate with enhanced Management Information Systems (MIS) to close the loop on all aspects of the production workflow, from quoting to invoicing, simplifying job ink consumption estimation and reusing existing ink formulations.

 

12. Waste Ink Reuse

The remaining ink can be mixed evenly and used as a base ink for further color mixing, significantly reducing ink waste, saving costs, and turning waste into treasure.

 

 

Digital Offset Printing Color Management Solution

To maximize color accuracy throughout the workflow, all inks and pressroom solutions must be integrated. X-Rite solutions create a seamless, automated, and closed-loop production solution for offset printing.

1) InkFormulation software

InkFormulation uses a job-based user interface to ensure efficiency by always grouping jobs and supports information exchange with MIS/ERP systems. In addition, all ink formulations required for a given job can be associated with the job, bringing significant value to packaging service providers and ink stations.

InkFormulation software is suitable for the eXact 2 spectrophotometer and is compatible with PantoneLIVE, thus supporting the use of new digital color standards.

Color Management - Spot Ink Matching Technology

 

2) eXact 2 Spectrophotometer

The new eXact 2 is equipped with specific functions for ink laboratories. It features a tilting screen that is 30% larger and has double the resolution compared to the first generation, with a refreshed interface and a high-resolution camera that can identify printing defects caused by ink. Smaller printed images can be magnified for precise viewing of small areas. For ink formulation, eXact 2 also allows for non-contact measurement to minimize ink adhesion and contamination. Additionally, it has a switchable polarizing filter for formulating and verifying inks on a wide range of substrates.

eXact 2 Series Next Generation Non-Contact Portable Color Difference Meter | X Redefines Color Measurement