There are many products that contain graphics to identify and promote a product or company. It is also used to give information about a product on the packaging such as weight, contents, ingredients etc.

Such products will be produced using a commercial printing process.

Letterpress

is one of the earliest methods of printing and involves raised letters onto which ink is coated. Paper is then pressed against the plates holding the letters. It is still used today for specialist printing such as personalised wedding invitations, but it can usually only print one colour at a time.

Laminating

There are two main lamination methods in relation to papers and boards.

Lamination via encapsulation

Lamination via a surface coating

Embossing

This creates a raised design on the surface and is an aesthetic effect although it can have practical applications such as applying braille to packaging.

Debossing

This is essentially the opposite of embossing and produces an indented depression rather than a raised surface. It may also be classed as an embossing process by some manufacturers as it essentially uses the same kind of tool and process.

Foil blocking

This process involves the application of heat and pressure to a metallic paper (foil) to create areas of depth and texture. This adds aesthetic impact to the product and give it a sense of ‘quality’. It is used on business cards, high quality menus and leaflets as well as book covers, gift cards, wedding stationary etc.

Varnishing, UV varnishing and spot varnishing

Varnish is a clear, non-pigmented ink only used on pre-coated papers and boards to enhance aesthetics as well as some protection against dirt and fingerprints. It is available in gloss, satin and matt finishes.

UV varnishing provides a smooth finish and is cured using UV light once the ink has dried.

Spot varnishing is applied to specific areas to make text or logos stand out. It canbe done with normal or UV varnish.

Screen printing has a number of different applications where inks or other materials need to be printed onto a flat surface such as:

• the transfer of designs onto paper and fabrics.

• the transfer of designs onto ceramics.

• for printed circuits for electronics products.

• the process was originally called silkscreen printing as ink was forced through a template via a silk screen and squeegee. Nowadays it is much more complex and can print onto curved surfaces.

Flexography

is a relief printing process similar to letterpress with the raised letters but in this case raised text and images are photo etched onto a rubber material which is glued onto steel rollers. The inks used are this and viscous which allows printing onto poorer quality materials such as waxed films and cellophane. This process is primarily used for packaging, carrier bags but also books and magazines.

Offset Lithography

is probably the most versatile and economic of the commercial printing processes and uses the same four colours (CMYK) through a series of up to five presses.

Gravure

is used to produce a range of high-volume materials such as postage stamps and banknotes through to catalogues and wrapping paper.

Stainless steel cylinders are engraved with tiny holes of varying depth which holds the ink.

Gravure is a very expensive process so is reserved for very long runs as any changes require whole new cylinders to be made.

Thermal transfer printing

applies the process colour one at a time by heating the wax to leave droplets of colour onto paper or acetate sheet.

Dye sublimation printing is a form of thermal printing where the dyes change from solid to gas while never becoming liquid.

Digital printing

processes include electro-photographic and inkjet printing.

Electro-photographic printing

involves the depositing of toner into the paper or card. Dry or liquid toners can be used but they are fixed by heat and absorption which explains why paper comes out of printers warm

Inkjet printing

involves spraying electrostatically charged ink droplets directly onto the paper relying on absorption to fix the inks.