AN INTRODUCTION TO DYE SUBLIMATION
Sublimation printing is a relatively new but fast growing system being adopted in schools. In essence it allows students to reproduce four colour images in the surface of various different materials.
WHAT IS DYE SUBLIMATION PRINTING?
‘Sublimation’ is defined as turning a solid into a gas and back into a solid without any liquid stage. This allows the application of sublimation inks into a materials surface using a Heat Press to provide the required combination of heat, time and pressure. This combination causes the inks to be converted from a solid to a gaseous state enabling them to penetrate the surface so that a permanent, full colour image is formed. The colour penetrates the material giving a result which is long lasting, colourful and resistant to scratching. Dye Sublimation should not be confused with other dry laser processes that transfer the images to the surface of materials making them easy to scratch off. True Dye Sublimation uses wet ink technology.
WHAT ARE DYE SUBLIMATION INKS?
Dye Sublimation Inks are in essence a formulation of special coloured dyes suspended in liquids that can be passed through a digital ink jet printer.
WHAT MATERIALS CAN BE SUBLIMATION PRINTED?
Suitable materials are man made polymers such as Polyester and PVC. These can be ‘hard’ such as a polyester coated sheet of aluminium or ceramic tiles or ‘soft’ such as polycotton textiles. During the heat press stage the pores of these polymers open to allow sublimation ink (now in a gaseous state) to enter. As the temperature drops the pores close leaving the now solid ink image as part of the polymer.
In an education environment printable materials fall into three distinctive categories
SUBLIMATION SHEET MATERIALS
These are varied but include polymer coated aluminium; PVC sheets; coated plywood, plastic sheets, polymer coated magnetic materials, fibreglass and polycarbonates.
SUBLIMATION MATERIALS ALREADY ON-SITE AT SCHOOL
Foamex board, PVC and other plastics for vacuum forming, textiles containing polyester more than 50%
MINI ENTERPRISE PRODUCTS
Sublimation clocks and jigsaws, bags, ceramic tiles, ceramic mugs, business cards, coasters, place mats, mouse mats, tee and polo shirts, glass chopping boards, pencil cases, aprons, sunshades, book marks,money boxes, phone covers and key rings.
All Sublimation materials tend to be white to enable true accurate colour reproduction. If you added an image to a coloured base the image would be distorted by the base sheet colour.
WHAT MATERIALS CANNOT BE SUBLIMATION PRINTED?
As dye Sublimation is always performed on a polyester, polymer or polymer coated item, materials such 100% cotton are not suitable as the natural fibres have no pores to open to accept the image. Cotton can be sublimated but the image will fade with a few washes making a 50% polyester 50% cotton weave a required minimum.
HOW DO YOU PRINT AN ITEM?
This is a digital printing system so you firstly select or create your colour image on a computer. Any picture from any software package will do - as long as it will print on a piece of paper it will be fine! Colour correction profile software is available but this is rarely necessary for sublimation printing in an education environment. If you are using the new Ricoh printers the image should be ‘flipped or mirrored’ in your application software, if you are not using the free Ricoh PowerDriver which performs automatic mirror imaging.
The image is normally sized so that it is slightly larger than the selected material so it can ‘bleed’ over the edge leaving no white showing. The image is printed on sublimation paper ‘mirror image’ and is then laid onto the sublimation material and secured with a little ‘heat tape’. The two are then placed in a Heat press for typically 1-2 minutes at a temperature between 160°- 200°c. The exact time and temperature depends on the material being used. At the end of the cycle the paper is removed to reveal a bright vibrant scratch resistant coloured image.
WHAT EQUIPMENT IS NEEDED FOR SUBLIMATION PRINTING?
Dye Sublimation High Capacity Ink cartridges for the Ricoh printer
Heat Press for flat material
Mug Press or domestic oven for mugs
Ricoh is now the chosen printer for sublimation. The special high capacity inks mean no ‘bulk feed ink system is needed’ The new Ricoh printers offered by Mega have very high print speeds, a self cleaning print head and high ink dispersion rates to prevent ink blockages. They use print head technology with virtually no heat being generated which means the ink does not sublimate in the printer. ‘Bubble Jet’ printers from manufactures such as HP, Cannon and Lexmark heat the ink in the head to force droplets onto the paper. This means all these types of printers are unsuitable for use with sublimation inks that react to heat.
DYE SUBLIMATION INKS
Patents exist for European and US desk top (to A2) printing of Sublimation inks. These patented inks are available in slightly different forms and brands within Europe but are all offered at approximately the same market price.
If you used low cost photo copy paper too much of the ink would absorb into the paper itself and not enough would be ‘Sublimated’ into the material. Sublimation paper has a coating on the surface which effectively means the ink sits on the paper without ever thoroughly drying. For the Ricoh printers we have a specially formulated paper which is quick drying but provides excellent colour saturation everytime. Customers printing very soft plastics should use the 'Sublimation Special' paper which will not stick to heated soft plastics.
HEAT PRESS, MUG PRESS AND OVEN
The constant even pressure and variable temperature control make a Sublimation Heat Press essential. Mugs will obviously not fit in a flat bed press so a special Mug Press can be purchased or alternatively the printed image adhered to the mug and the two placed in a domestic oven for 10 minutes.
Sublimation Printing can be used in conjunction with other manufacturing processes. For example; clear or white PVC sheet can be sublimated and then allowed to cool in the flat. The printed plastic can then be vacuum formed. A video resource is available from Mega which shows a vacuum forming tool being made on a laser cutter and the clear PVC being sublimated before it is vacuum formed to produce a colourful three dimensional light switch cover for a child’s room. Another example of sublimation printing and thermo-forming is with foam board. This can be printed and when it is still warm from the press formed into shapes using a simple press forming tool.
WHO IS USING SUBLIMATION?
In Schools and Colleges Sublimation is suitable for use in a wide range of areas. These include Graphic Products; Engineering; Product Design; Food Technology; Art and Design; Textiles and Enterprise.
Starter Kits containing a digital heat press, Ricoh printer, papers, inks, and heat tapes are available from £1250 plus VAT
Printing costs are difficult to equate as it often depends on how often the system is used and therefore how many cleaning cycles and head cleans the printer performs. Best estimates however for a flood coat A4 image are between 40p and 50p for both ink and paper.
HOW RELIABLE ARE THE PRINT SYSTEMS?
The new Ricoh printers used in conjunction with SubliJet sublimation inks are efficient and reliable. Test have shown that even if the system is to be left dormant for several months a nozzle check and head clean is all that is needed for trouble free use.
WHERE DO YOU BUY?
Mega Sublimation Printing is a division of Mega Electronics Ltd. Mega has been supplying schools for over 30 years with electronic teaching systems. A large part of the business has always been systems to enable customers to produce their own signs and labels; sublimation printing is one such system. Mega has been selling sublimation products to schools for five years and offers complete range of equipment and materials and most importantly a comprehensive level of training and support.
Mega Sublimation Printing offers various free support documents, an illustrated materials booklet and a CD resource featuring four different videos. Free on-site demonstrations are available.
Sublimation Printing - Educational Uses:
Sublimation Printing - The Process:
Sublimation Printing has 3 stages. 1. Print Your Own Design. 2. Lay Printed Design On Substrate And Heat Press. 3. Remove Printed Substrate. Check out the demonstration of the Sublimation Printing Process below.