Design Productions // Design for print - Print Process research

Our aim was to learn the main forms of print process that can be used and what process is suited to what print job, stock or products.

This will be my first proper look into print processes, I am looking forward to finding out more about this area as it will give me some more confidence into making decisions of how projects will be printed and how I could change the process to change the visual effect.

Rotary printing

Typically the rotary print process involves the printer passing a roll of stock between two rotating drums. One of the drums will be partially submerged in an inkwell, this is the drum that will have the image to be printed cut into it's surface or cut into a plate which is curved round the drum. The second drum presses the stock against the first drum to ensure image transfer, there is also typically a tool called a 'Doctor blade' used which will scrape against the first roller and catch any excess ink, this will ensure that only the image will be printed with no blobs or unintentional marks.

Offset Lithography

- Large Quantities

- Metal / Rubber Roller

- Etched Aluminum plate

Used for printing on flat surfaces so can not be used for printing onto 3D products. An image is applied to a plate, which can be made of many different materials but usually you will find it will be aluminum.

The plate is chemically treated to ensure ink only is picked up in the area's which have image or text. water and ink is then applied to the plate, because of the chemical treatment the ink will only attatch to the image area and will be rejected from any blank part of the print.

The plate is then pressed against a rubber roller and the image is transferred (this is called a blanket) the rubber roller is then rolled over the stock and the image is applied.

 The process is called 'offset' because the plate does not come into direct contact with the stock.

Web Offset Printing

- High Speed

- Prints onto rolls of paper rather than individual sheets

- Paper folding mechanism incorporated into printer which is ideal for publications such as newspapers.

- Built for large quantity prints

- Fast turnaround of high quality prints

Useful Website - Print Brain

This is quite a cool little video about using offset web printing to produce newspapers

Rotogravure Printing

Useful website - BOBST

How it works

- Copper Printing plate or cylinder

- image engraved into printing plate

- ink sits in wells of engraved image

- raised layer is cleaned and scraped of ink

- printing material is pressed onto plate to transfer print

- Ink directly onto print surface

- Durable plates

- Longer print runs

- Plates are thicker than aluminum plates so they can hold thicker inks  

Products produced - 

Stocks for Rotogravure printing

'Rotogravure process is an intaglio method of printing, meaning that the pictures, designs and words are engraved into the printing plate or printing cylinder. Acid is used to cut the images into the plate. Once the copy is photographed, positives are then made from the negatives. The images are transferred to the printing surface by use of carbon tissue covered with light-sensitive gelatin. The gelatin hardens based on the amount of light that passes through the positives. The plate or cylinder is then bathed in acid, which eats through the gelatin squares. On the printing press, the deepest cells retain the most ink and the darkest tones.'

Flexographic printing 

- Rubber Polly Plates

- Sticky Inks

- Prints directly onto stock surface

- Precise and clean print quality

- usually print onto low quality, cheaper stock

- Low cost  

Products produced -

Source - Flexography Printing Process

'Frequently used for printing on plastic, foil, acetate film, brown paper, and other materials used in packaging, flexography uses flexible printing plates made of rubber or plastic. The inked plates with a slightly raised image are rotated on a cylinder which transfers the image to the substrate. Flexography uses fast-drying inks, is a high-speed print process, can print on many types of absorbent and non-absorbent materials, and can print continuous patterns (such as for giftwrap and wallpaper).

Also known as flexographic printing or flexo, some typical applications for flexography are paper and plastic bags, milk cartons, disposable cups, and candy bar wrappers. Flexographic printing may also be used for envelopes, labels, and newspapers.'

Digital Print

- Printed from digital file

- Prints straight onto stock

- Short print runs

- More specialist prints   

Digital printing is the reproduction or copying of any digital image on to various types of physical surfaces as a rule. Some of these physical surfaces for example can be any of the following. They are:

- Film

- Cloth

- Plastic

- Photographic paper

- Regular paper

Screen Printing 

- Mesh Screen

- Hands on/ Man produced

- Commercial print in specialist areas

- Quite an expensive print process 

'Screen printing is a printing technique that uses a woven mesh to support an ink-blocking stencil. The attached stencil forms open areas of mesh that transfer ink or other printable materials which can be pressed through the mesh as a sharp-edged image onto a substrate. A fill blade or squeegee is moved across the screen stencil, forcing or pumping ink into the mesh openings for transfer by capillary action during the squeegee stroke.'

Products produced -

Pad Printing

- Prints onto balloon

- Balloon wraps printing surface

- 3D Objects

- Any surce 

Below is a useful website that explains the step by step process of pad printing, which explains how this process is unique compared to other print processes. i think the main benefit in using Pad printing is the fact that it can print straight onto 3D objects such as bottles, toys, containers, tins etc.

Source - Teca-print USA