For the production of printed garments for promotions, merchandise and fashion there are mainly 3 particular methods of screen printing employed. The method most commonly used and best suited for a large variety of graphics is called ‘Spot Colour’ printing. Spot colour printing is the most suitable method used for the printing of graphics that are not photographic in nature.
The colored ink that is used in reproducing graphic images are chosen by a graphic designer and more often than not are Pantone specified colors. Pantone coated or uncoated colour references are chosen to specify the ink colours of the design. The Pantone matching system is an international colour reference used in publishing, printing and design whereby each colour is identified by a unique pantone name and number.
When colour identity and uniformity is an issue, for example in branded promotional garments or a large selection of products, this method of spot color printing works very well.
The Four Color Process is another method used in tshirt screen printing. This printing process is utilised primarily with photographic designs and sketches comprised of a broad variety of hues, shades and gradations. All magazines and books use this four-color printing process as well.
The inks are transparent and blend with one another on a white backdrop to recreate each of the colours and shades that the original possessed. It is much harder to do the same on cloth rather than than paper. But the method that is utilised is virtually identical.
This method of tshirt printing is only useful for white garments, and will not work well on coloured fabrics.
The print set up costs are higher than that of simple spot colour designs and as such only suitable for larger print runs of 100+. When t-shirt printers reproduce such full colour images onto coloured fabrics a method called ‘Simulated Process’ is used. The artwork is divided into different hues and tones utilising a process that resembles spot colour printing in order to obtain the overall appearance and style of the original picture.
Most t-shirt printers use this method, and it is especially popular when used to copy fantasy and heavy metal album artwork onto shirts to be sold by the band. Colour separations and the number of colors necessary make this the most expensive printing option, and the higher set-up costs mean it is usually reserved for larger runs.