Printing Technology Overview

Printing Systems 1

• This course is about printing technologies, including conventional and non-impact printing.
• Modern printing technologies rely heavily on computer and information technology.
• Current printing technologies draw from discoveries in engineering, information technology, physics, and chemistry.

Printing Technology

• Printing technologies are categorized as conventional (requiring a master) or non-impact (masterless).
• Conventional printing methods use a printing plate (e.g., lithography, gravure, letterpress, screen printing).
• Non-impact printing uses technologies like electrophotography and inkjet.
• All printing technologies transfer information to a substrate (e.g., paper).
• The process involves prepress (preparation), press (printing), and postpress (finishing) phases.

Printing Technologies with a Printing Master

• Conventional printing technologies require a master (printing plate).
• The printing plate carries information using ink or lack of ink.
• The plate often breaks down the original image into smaller dots (screen dots) to allow for continuous tones.
• This process is called screening.
• Screening converts gray scale images into binary images enabling transfer of information.

Printing Technologies without a Master (NIP Technologies)

• Non-impact printing (NIP) technologies don't require a physical image carrier.
• They can generate a different printed page for each print.
• Digital systems are frequently associated with these technologies.
• They often use printing processes like dot matrix printers, but technology has evolved significantly.
• The production process needs the printed page information in digital form.

Definition of the Most Important Terms Relating to Printing Technology

• Printing is the process of applying ink to a substrate to transfer information
• The printing plate is the tool (tool material) for the ink transfer.
• Ink is the colored substance applied to the printing substrate.
• The printing substrate is the material that receives the print.
• The printing press is the equipment used in the printing process.

Printing Systems: Various Methods

• Letterpress involves raised printing elements (letters, lines).
• Gravure involves recessed printing elements.
• Lithography has printing areas and non-printing areas on the same level.
• Screen printing uses a mesh plate with blocked elements.
• These all vary in image carrier types.

Prepress Operations

• Prepress is the process before the printing, involving several steps for formatting information on the page.
• Traditional prepress includes text formatting, and creating layout for photos and graphics.
• Composition (text arrangement, formatting), reproduction (color separations for pictures), and platemaking (creating image carriers for presses) are included in this phase.
• Pre-flighting checks digital artwork prior to printing to prevent potential problems (color, size, technical).
• Raster Image Processor (RIP) translates data into printing press-ready format
• Proofs(digital or physical versions of final product) are presented for approval before actual printing
• Digital prepress uses electronic input data, for the preparation and output steps in the process of the preparation for printing

Steps in the Process

• Prepress departments verify print quality before printing actual product.
• Pre-flighting (checks files to find issues), is a crucial part of the prepress stage.
• Pre-flighting helps prevent costly issues like remaking plates, re-printing, or re-doing the whole job.
• Preflighting detects problems (color, fonts, etc.) that could negatively affect the print run.

The Second Stage: Raster Image Processor(RIP)

• RIP converts data from the file into a format suitable for printing press.
• This process creates dot patterns from continuous colors using software.
• Separates data into color components (cyan, magenta, yellow, black)

The Fourth Stage: Printing Plates

• Printing plates are created for offset presses if needed.
• Plates are mounted on cylinders in the printing process
• Each color requires its own printing plate and cylinder.
• Ink is transferred from the plate to the blanket, and then to the printing paper.
• This is a crucial phase in the printing process for offset presses

Letterpress Printing

• Letterpress, a historic printing method, uses raised printing elements to transfer ink to the substrate.
• Letterpress uses plates of lead, plastic, or rubber.
• Plates are then placed on a press and pressed against the substrate.
• Image carrier is either flat or wrapped around a cylinder to allow for rotary prints
• Common printing methods for books, posters, documents, etc.

Flexographic Printing

• Flexography involves an image carrier commonly made of rubber or plastic, enabling printing on a wide array of substrates.
• It uses very viscous inks.
• It is one of the most commonly used forms of printing on flexible substrates such as packaging and labels

Letterpress Inks and Drying Systems

• Paste inks are used in letterpress systems.
• Letterpress inks are high-viscosity and similar to offset litho inks in properties.
• The process often requires drying processes or special inks.