What are image areas?
Areas that attract ink and repel water
What are non-image areas?
Areas that repel ink and attract water
What is the first stage of offset printing?
- Plate preparation - aluminium plate is treated chemically to create areas that attract ink (image areas) and areas that repel ink (non-image areas)
What is the second stage of offset printing?
- Ink and water - the plate is dampened with water which adheres to non-image areas and repels ink. Meanwhile, ink is applied to the image areas, adhering due to their affinity for oil-based substances
What is the third stage of offset printing?
- Image transfer - as the plates rotate on the press, the inked image is transferred onto a rubber blanket cylinder.
What is the fourth stage of offset printing?
- Printing surface - the image is transferred from the rubber blanket onto the paper or other material, resulting in a high-quality printed image.
What are the advantages of offset printing?
- high quality
- consistency
- versatility
What are the disadvantages of offset printing?
- set up time, time consuming and expensive so not efficient for small runs
- complexity in colour matching, requires expertise
- waste in start up, more initial waste in materials and time
- not ideal for personalised prints
What is the process of lithographic printing?
- The image is drawn onto the surface using materials that repel water but attract oil-based inks
- The surface adheres to hydrophilic areas while being repelled by the hydrophobic areas when treated with water.
- Oil- based ink adheres to only the image areas resulting in transfer of the image onto the surface
What are some advantages of lithographic printing?
- versatility in substrates, can be used on many different surfaces
- accurate colour reproduction
- high quality prints
- cost effective for large runs
What are some disadvantages of lithographic printing?
- high set up time and cost
- isn’t suitable for personalised prints
- susceptible to plate damage
- environmental concerns with chemicals used to clean plates
What are some applications of lithographic printing?
- fine art
- commercial printing
- packaging
What is flexography?
A printing technique that utilises flexible relief plates to transfer ink onto various substrates, typically made of rubber or polymer.
What are some advantages of flexography?
- high speed
- quick set-up
- cost effective for large runs
- versatility
What are some disadvantages of flexography?
- lower print quality compared to other techniques
- plate prep can be time consuming
- environmental concerns with inks and solvents used
What is screen printing?
A pencil- based printing technique that involves using a mesh screen to transfer ink onto a substrate
What is the first stage of screen printing?
- Stencil creation - stencil is made by blocking areas where ink should not pass through on the mesh screen using the process of photo emulsion for e.g.
What is the second stage of screen printing?
- Ink application - ink is placed at the top of the screen and the spread across the stencil using a squeegee which forces the ink through the mesh onto the substrate, transferring the image onto the surface.
What is the third stage of screen printing?
- Printed image - the ink passes only through the open areas of the stencil onto the substrate, creating the desired image or design.
What is the fourth stage of screen printing?
4 . Wash off screen - jet wash any excess paints off the screen
What are some advantages of screen printing?
- versatility
- durability
- customisation
What are some disadvantages of screen printing?
- complexity for multi-colour prints as each colour requires a separate screen
- detail limitation in small, intricate designs
- long set up and clean up process
What is gravure?
A high quality, intaglio-based printing technique that employs sunken cells or recessed areas on a cylinder to transfer ink onto a substrate.
What is the process of gravure?
- Engraving - image is etched onto the cylinder in the form of tiny, recessed cells
- Ink application - ink is applied to the cylinder, filling the recessed areas while the surface is wiped clean
- Image transfer - the substrate is pressed against the cylinder as it rotates and the image is transferred onto the surface.
