When you decide to purchase your promotional items you may be given a number of options involving how the item can be printed. Here is our stab at explaining some of the terminology you may be faced with.
Spot colour printing creates brighter, more vibrant results, but with a smaller colour range. When printing in spot colours, a single colour ink (normally with a Pantone reference number - see below) is applied to the printing press roller.
4 colour process
This is the process of printing photographs or other documents in the full spectrum of colour. This printing involves the use of four plates: Cyan, Magenta, Yellow and Keyline (Black). The artwork is separated into these four colours – one plate per colour. The four CMYK inks are applied one by one to four different rollers and the paper or card (‘stock’) is then fed through the printing press. The colours are applied to the stock one by one, and out comes the full colour (4 colour process) result. This is the process of printing photographs or other documents in the full spectrum of colour.
What is a Pantone Reference
A standard reference which allow designers to "color match" specific colors when a design enters production stage, regardless of the equipment used to produce the color. Pantone colors are described by their allocated number (typically referred to as, for example, "PMS 130").
Screen printing
Basically, it is the process of using a mesh-based stencil to apply ink onto a substrate, whether it be t-shirts, posters, stickers, vinyl, wood, or other material. One colour is printed at a time (layered over any previous colour), so several screens will need to be used to produce a multicoloured image or design.
Digital printing
Digital printing refers to methods of printing from a digital based image directly to a variety of media. The fact that the digital printer does not use screens allows for a photographic print, with much more detail than traditional screen printing. As this method avoids the cost of all the technical steps required to make screen printing plates it can often work out cheaper particularly when the logo etc has more than 1 colour.
Dye-sublimation
Using a computer printer which employs a printing process that uses heat to transfer dye onto materials such as a plastic, card, paper, or fabric.
Transfer printing
A method of decorating enamels or ceramics using an engraved copper or steel plate from which a monochrome print on paper is taken which is then transferred by pressing onto the ceramic piece
This is because the more familiar .jpg images are specifically designed for viewing on a computer screen but screen print process requires high resolution images which contains more information about the image and ability to create three colour separations needed for screen printing.
The main difference is that a JPG file is a compressed file, where each pixel in the image is saved with its RGB value (or CMYK). Each time you open and save the image there is further and further compression happening. Also, images in this format are very difficult to resize, because you have a 1:1 representation of what the image is.
Post script files, like EPS (Encapsulated Post Script file) are in an a scripting language called Post Script, where the images are actually saved as mathematical formulas, coordinates and vectors. This not only allows for much smaller file sizes, but also resizes much better and produces much better results at the time of printing, because there are printers that actually read post script and process the images in real time as they are printed, versus having the computer read the pixels and tell a printer what to print.
