13 Digital Printing Technology
Learning Objectives • Explain how digital processes have affected the graphic communications industry. • Compare digital printing technologies. • Explain the practical uses of variable data printing and distributed printing. • Recall the purpose of digital asset management systems. • Summarize the advantages and disadvantages of digital printing.
Digital Printing Overview • Digital printing technology • Eliminates time-consuming and costly preparation of film, plates, and inks • Provides customers with options that bring professional printing closer to desktop • Reduces number of workflow steps, making process simpler and more productive
Digital technology is used to: Create text Capture or create images Create printing plates Apply ink or toner Major technologies include: Electrostatic technology Ink-jet printing technology Digital Printing Overview
Direct Imaging (DI) • Computer-to-press system • Eliminates production steps and variables normally associated with offset processes • Provide good image quality and reduced environmental footprint • Reduces makeready time and improves productivity
Digital Workflow • Creation of text and images • Importing text and images to create page layouts • Imposition and sheet assembly of laid-out pages • Platemaking and printing based on sheets on DI press
Digital Printing Methods • Ink-jet printing is most common • Other types: • Electrostatic printing • Ionography • Magnetography • Dye sublimation • Thermal transfer
Ink-Jet Printing • Uses digital data to control streams of droplets of ink or dye • Mostly variable data printing of single or spot colors • Three classifications • Desktop • Large format • Grand format
Types of Ink-Jet Printers • Thermal ink-jet printers • Use electrical current, heat, and nozzle to transfer ink to substrates • Piezoelectric ink-jet printers • Use piezocrystals • Continuous ink-jet printers • Use continuously circulating flow of ink
Types of Ink-Jet Inks • Aqueous inks • Withstand high temperatures without affecting chemical makeup of ink • Solvent inks • Have ingredients considered to be high in VOCs • UV-curable inks • Lack of VOCs
Volatile Organic Compounds • Chemical compounds that emit vapors at normal room temperatures • Short term exposure to VOCs can cause: • Irritation to eyes, nose, and throat • Headaches, dizziness, or nausea • If using products containing VOCs, follow all safety instructions
Types of Ink-Jet Printheads • Fixed-head ink-jet printer • Built-in printhead • Printhead can be refilled when ink runs out • Disposable head ink-jet printer • Cartridge is replaced when ink runs out
Electrophotography • Most often seen in copiers • Most systems accommodate wide range of papers • Some are being used to produce content and contract proofing, including final output copies
Electrophotography (www.PrintingTips.com, owned by Austec Data Inc. dba Tecstra Systems)
Ionography • Used mainly for single- or spot-color printing • Used for high-volume and variable data printing (www.PrintingTips.com, owned by Austec Data Inc. dba Tecstra Systems)
Magnetography • Image is converted to magnetic charge on drum that then attracts magnetized toner • Faster than other types of systems • Commonly used for: • Single- or spot-color printing • Barcodes • Other types of variable data printing
Dye Sublimation • Type of thermography • Ribbon made of panels of CMY pigments pass over heater • Pigments become gaseous and are transferred to substrate below panels • Ink is dry as soon as it is done printing • Panels cannot be reused
Thermal Transfer • Type of thermography • Similar to dye sublimation • Printers use different ribbon for each color • Used mainly for one-color printing • Newer systems have multiple ribbons of different colors • Commonly used for color proofing
Digital Printing Applications • Variable data printing • Distributed printing • Digital asset management (DAM)
Variable Data Printing • Enables quick and easy content changes at several points within print run • Basic template of printed material has certain sections designated as changeable fields • Produces customized and personalized materials
Distributed Printing • Electronic files are sent through WAN to be printed near point of distribution • Using color management systems at both ends of process helps ensure color consistency
Tasks include: Downloading data Processing data Organizing data Storing data Transmitting data Software-as-a-service (SaaS) Data includes: Design files Templates Images Font files Databases Digital Asset Management (DAM)
Advantages and Disadvantages of Digital Printing • Digital presses offer quick turnaround times, greater flexibility, and cost-effective printing for short color runs • Eliminating much of traditional press preparation reduces overall cost of short color runs • Most digital presses do not produce high enough quality
Electronic Media Waste • When computers and other types of electronics are thrown out, they become e-waste • E-waste is fastest growing cause of toxic waste in United States • Toxic chemicals found in e-waste can consist of lead and mercury
Review What is direct imaging (DI)? The process of sending digital files directly to press without use of traditional offset or computer-to-plate processes or chemistry.
Review What are two types of thermography? How do they differ? The two types are dye sublimation and thermal transfer. Dye sublimation printers use a ribbon of panels of colored solid pigment. Thermal transfer printers use a different ribbon for each color.
Review What is variable data printing? What is it used for? A type of printing that enables quick and easy content changes at several points within a print run. It allows customized and personalized materials to be produced.
Review What is digital asset management? The protocol and resources established to handle all digital files and data.
Review What are three advantages of digital printing? Quick turnaround times, greater flexibility, and cost-effective printing for short color runs.