APPAREL VIEWS / AUGUST 201068

Usage of sublimation printingin apparel and textiles

VASANT R KOTHARI

has done Master’s in

Textiles Technology from

DKTE’s Textile and

Engineering Institute,

Ichalkaranji (Shivaji

University, Kolhapur),

Maharashtra. He has also

done Diploma in Export

Management (Apparel

Export) from the Indian

Institute of Export

Management, and

Garment Export and

Merchandising

Management from NIFT,

Bangalore. Presently, he’s

working as an Assistant

Professor in Department

of Fashion Technology,

NIFT, Bangalore.

The desire to create garments and other artefacts

that reflect the beauty of the world around us and

provide for the expression of our artistic nature has

been evident from early in human history. The

decoration of the body presumably predates the

production of clothing. Textile printing is the most

versatile and important of the methods used for

introducing colour and design to textile fabrics.

Considered analytically, it is a process of bringing

together a design idea, one or more colorants, and a

textile substrate (usually a fabric), using a technique

for applying the colorants with some precision.

Several techniques have been used and the colorants

available have multiplied, the latest and the most

popular is sublimation print.

We have learnt in Chemistry that an element or

compound normally has three states viz. solid, liquid

and gaseous state and conversion from one state to

another can happen by applying heat

(solid>>liquid>>gaseous) or by removing heat

(gaseous>>liquid>>solid). However, there are

certain elements where only two states exist viz.

solid and gaseous. Thus in these elements, when

heat is applied, an element gets transformed into

gaseous form without intermediary liquid form

(solid>>gaseous). This process of transformation

is called "sublimation.” Dye sublimation printing uses

above property to transfer any image/artwork from

one surface to another. Popular uses are to transfer

images on T-shirts. A dye which sublimates under

pressure and heat is mixed with the inks.

Dye: To impregnate colour into a material.

Many times this colour change is permanent.

Sublimation: A change directly from the solid

to the gaseous state without becoming liquid.

Polymer: Consisting of large molecules made

up of a linked series of repeated simple

molecules.

Dye sublimation: Solid dye particles are

changed into gas using heat and pressure, then

bond with any polymers present, and change

back into a solid.

Printing process

In this printing technology, the print heads get heated

up while passing through the film; this forces the

solid dyes to get vaporised and diffused on the glossy

surface of the printing media, which in turn creates a

gentle gradation for each pixel at their edges.

The ribbon consists of three coloured panels (cyan,

magenta, and yellow) and one empty panel to hold

the lamination material that is used as over-coating.

The whole printing cycle is repeated for four times

where the first three cycles lay the colours onto the

media to form a complete image, while the last one

to give a laminated top. This is to prevent dye from

re-sublimating when exposed to warm conditions.

The dye particles that are used

for this type of dye sublimation

are designed to only bond with

polymers, so the higher the

polyester content in the material

the more dye that will bond giving

a brighter image.

Sublimation dyes are permanent

as they have become part of the

fabric, and thus give the

excellent fastness properties.

The only way that colour is going

to come out is possibly if fabric

is kept in the sun for the next

two or three years but then the

material will probably sun rot

before the dyes go away.

The ribbon

Transfer print

The images are initially printed on coated transfer

paper as a reverse image of the final design, which is

then transferred onto polyester fabrics in a heat press

operation. Under high temperature and pressure, the

dye turns into a gas and permeates the fabric and

then solidifies into its fibres. The fabric is permanently

dyed so it can be washed without damaging the quality

of image.

Direct print

The images are directly printed on treated polyester

fabrics, which are then heated by heat-fixation devise

that fixes the colour on the fabrics. This method

eliminates the need for transfer papers. This means

Types of sublimation print

Sublimation print can be classified as two types, viz

transfer print and direct print.

Sublimation print

Direct printTransfer print

APPAREL VIEWS / AUGUST 2010 69

no paper cockling and reduction in defects such as

ghosting and various wave or tiger stripes that are

common in roll-to-roll transfer printing. This type

needs an ink waste pit to collect excess ink and

prevents it from staining the reverse side of the fabric.

Application of sublimation print

Sublimation print is widely used on polyester, satin and

some other synthetic fibres. The sublimation dye actually

penetrates the fibres and becomes part of the fabric.

And nothing is felt! The high temperature during the

printing also opens the pores of the polymer and allows

the gas to enter. When the item is removed from the

heat press, the temperature drops, the pores close

sublimation process produces permanent images that

will not crack or fade. Also, sublimation infuses the

image into the thread of the fabric so that it does not

affect the breathability of the garment. Most athletes

prefer sublimated jerseys versus screen printing

jerseys. Screen printing leaves a layer on top of the

garment, which affects breathability and the comfort

of the athlete.

Dye-sublimation is also cost efficient and very popular

for short-run customisation of fabrics. Special logos,

pictures and designs can easily be created or scanned

into the computer. Transfer paper can be generated

and custom prints finished in a matter of minutes as

opposed to screen printing, which requires lengthy

time for preparation of the stencil and assembly of

the mesh fabric.

Pros and cons of sublimation print

Pros

• Dye sub is great for full colour designs on white or

light coloured garments

• It has no feel to the design

• Vibrant colours can be achieved

• Full colour printing is possible

• The colours are still vibrant after many washes

• There is no crack or fading of colours in this type of

printing

• Dramatically reduced waste and maintenance costs

• Excellent coverage and extended ink yield

• Trouble-free unattended printing and maximum

uptime

Cons

• It can only be printed on white colour

• Suitable for dry fit, silk, polyester fabric

• It cannot be printed on black or dark colour fabric

• Metallic colours are not possible

Conclusion

With the new generation of wide-format digital

printers and the expanding variety of speciality media

designed for printing, the creative possibilities for

producing applications using dye sublimation are

endless. Prior to these technological advancements,

entering the dye sublimation market required a

considerable investment of time and money, but now

it is often favoured as a less expensive alternative to

other printing methods

Front and back printed with sublimation print

and the gas reverts to a solid state. It has now become

a part of the polymer. Sublimation print cannot be

washed out or come off, unless the actual fibres or

coating is damaged. This is why sublimation can't be

done on natural materials, like 100 per cent cotton.

Natural fibres and non-coated materials have no "pores"

to open and so the dye just sits on top of the fabric.

Further, sublimation print is done on white substrates.

The reason for this is because the inks are actually

transparent, when sublimated, and need a background

to show up. White is the ideal background because it

does not clash with the colours. Indeed, the white

background actually enhances the colours.

Comparison with screen printing

Dye-sublimation print on polyester material does not

affect the hand of the material and is more desirable

than screen printing for home furnishing and wallpaper

fabrics and the apparel industry. The colours are very

vibrant, do not wash out and the process is less messy

than screen printing, which requires messy solvents

and dyes.

Sublimation is also very popular with sportswear

manufacturers as many printed uniforms (cyclewear,

soccer, basketball and lacrosse) on the market today

are done via sublimation. Unlike screen printing,

where the ink lays on top of the garment, the

Transfer print Direct print