Sublimation printing is a technology that allows you to print on a variety of fabrics and face very different markets, from sportswear to exhibitions.
In this article, you will find content on sublimation printing made with 160 cm sublimation plotters. You will not find content on a small format sublimation printer in Pakistan.
The article is divided into three parts:
- The principle of operation of sublimation
- What you need to start a production of sublimation printing on fabrics
- Opportunity of the sublimation market
I decided to write this article, because although sublimation printing in Italy is growing, here in Sicily the diffusion is still minimal, almost non-existent.
I will therefore try to accompany you to discover sublimation and possible markets to be developed, advantages and market niches, with a focus on Sicily!
If you are interested in the subject let’s start with 5 fundamental points
As always, I recommend that you consult the index of contents to find the answers you are looking for immediately.
The sublimation market in Sicily
- Sublimation printing perfectly meets the new needs of the printing market on very light and easy-to-carry fabrics.
- Since Sicily does not have an advantage in land transport it could make you competitive for shipments.
- Sublimation is a green technology as polyester fabrics are completely recyclable unlike PVC.
- In the field of sportswear and fashion, small runs of a few units can be printed up to large productions of thousands of pieces.
- In Sicily one might think of printing articles for “beach fashion” such as swimwear, beach towels and hotel accessories such as terry slippers or TNT bags, since we don’t miss the sea, why not probe the market.
With the same peripheral it is possible to range in different markets from flags to interior design, to promotional and gift items.
These market possibilities are also due to the evolution of increasingly reliable printing systems and an expansion of the fabrics that can be printed.
After this introduction, let’s move on to the technical characteristics of sublimation printing.
Characteristics of sublimation printing on fabric
The magic of sublimation lies in the ability of the ink to turn into gas when subjected to precise heat and pressure, so as to penetrate inside the fabric, without leaving any thickness.
The main feature of sublimation printing is that it occurs only on polyester or mixed cotton/polyester fabrics, or nylon.
The best color results are obtained on 100% polyester fabrics, but it is possible to use fabrics with a cotton percentage with a minimum proportion of 60-65% polyester 35-40% cotton.
The greater the presence of polyester, the brighter the colors will be.
In case you want to print objects, know that the gadgets must be pre-treated with a polyester coating, in this way they will be receptive to sublimation inks.
As just mentioned in printing on polyester, the sublimation ink penetrates the fabric or the coating of the objects with a combination of heat and pressure given by the calendar or thermo press.
In the case of printing on 3D objects, such as covers, it is necessary to use a vacuum oven.
It is not possible to do sublimation on 100% cotton t-shirts, the ink does not set and the result is a faded and unsaleable print.
It is not possible to print on fabrics with dark or colored backgrounds because in sublimation there is no white color that can be used as a background unlike direct printers for t-shirts or screen printing.
I’ll give a trivial example to give an idea… think about using a highlighter.
If the page is blank, you see the sharp trace left by the highlighter.
If you do the same operation on a black sheet you don’t see anything, the same way sublimation printing works
If you need to print on white or colored cotton sweaters I recommend reading this article where I have deepened the topic:
What to choose between T-shirt Printer and Plotter for printing and cutting
After the transfer onto the fabric, the texture remains unchanged as the sublimation printing has no thickness, the color remains trapped inside the fibers of the fabric and the colors are brilliant.
In addition, the prints have a long resistance to washing and the fabric remains breathable.
For this reason, sublimation printing is the most suitable for sportswear as it allows normal skin transpiration, which would not happen, for example, with the use of laser-printed transfers or with an eco-solvent plotter.
With sublimation, the advantage of digital printing is maintained, i.e. there are no installation costs unlike screen printing, and it is also possible to make samples.
To go into the details of the production process we must now distinguish between the two different types of large format sublimation printing :
- Direct sublimation printing
- Indirect sublimation printing
Let’s see how they differ …
Sublimation printing on fabric: Differences between direct sublimation printing and indirect sublimation printing
We have said that sublimation printing on fabric differs in two technologies:
- Direct sublimation printing
- Indirect sublimation printing
In indirect sublimation printing, the plotter prints on a transfer paper reel which is subsequently coupled to the fabric which is sublimated by means of a heat press or calendar.
With direct sublimation printing, on the other hand, the plotter prints directly on the fabric.
The ink is immediately fixed on the fabric by means of an oven placed in line with the plotter or, at a later stage, printing through an offline calendar or oven.
These two technologies solve precise production needs.
I want to go into detail and with the help of some infographics show you the two different production cycles.
Direct sublimation printing
The roll of fabric is loaded into the direct sublimation plotter and the print head prints on it.
Clearly following the principle of sublimation ink, the ink must be exposed to a heat source to enter the polyester contained in the fabric.
The printed fabric is fixed in two ways
1) An oven is installed in front of the plotter which drags the printed fabric inside and with a constant temperature activates the sublimation process and fixes the ink.
2) The fabric is rewound after printing and then passed into an oven or roll-to-roll calender
In the event that the direct sublimation printing system with an in-line oven is adopted, the printing speed of the plotter is linked to the drying speed of the oven, i.e. even if you could go to 30 m2 / h but the oven does not support this speed, for that type of fabric I will be forced to reduce the print speed.
On the other hand, with the solution of the oven or calendar offline, you can print at the desired speed and then fix the ink with the speed suitable for the type of fabric.
Direct sublimation printing is perfect for printing flags and for the so-called soft signage and that is for the production of banners, banners, and in general fabrics for the decoration of points of sale and fairs.
For simplicity, I have collected in a list the strengths and weaknesses of this technology, also comparing them to indirect sublimation printing with the transfer.
Strengths of direct sublimation printing.
- The ink penetrates more into the fibers, thus ensuring better double-sided printing in the case of flag printing
- Dispersed inks can be used which provide greater resistance outdoors
- No sublimation paper is used and you save a cost
- In the case of the in-line kiln, the operator having to mount the transfer reel in the calender is eliminated, reducing labor costs
- By using the appropriate fabric, the print on the flags can be seen on both sides when printing on one side only.
Weaknesses direct sublimation printing
- Not all fabrics can be printed and must be pre-treated to prevent ink droplets from expanding upon contact with the surface of the fabric. This translates into a smaller choice of fabrics to sublimate than indirect sublimation printing.
- With the solution of the direct sublimation printing plotter with oven mounted in line, there is a production of vapors close to the print head, for this reason it is necessary to pay close attention to correct maintenance to avoid problems with the heads and the electronics of the plotter.
- You are forced to use perfectly flat fabrics to prevent the head from touching the fabric and causing damage
- Depending on the type of plotter you cannot print fabric spools that have filaments in the selvedges.
- You cannot work with the marker (see the paragraph dedicated to the grille for more details)
- On entry level sublimation plotters you cannot print elastic fabrics such as lycra. You can print it with industrial machines that have an adhesive mat that blocks the fabric before printing.
- The fluorescent lamps contained in the ovens wear out over time and must be replaced.
- Indirect sublimation printing is more qualitative . The detail guaranteed by printing on a coated paper will always be greater than the detail of direct printing on fabric.
- If the print comes with defects, the fabric is thrown away, which is much more expensive than transfer paper.
Although the weaknesses compared to indirect printing are many, in reality, it can be the best solution for targeted productions on flags and soft signage.
Indirect sublimation printing on transfer
A roll of transfer paper is loaded in the sublimation plotter for indirect printing.
The printing of the file must always be mirrored in the case of writings, logos, and sponsors.
When the plotter prints on the transfer paper the colors are off, but it is completely normal the magic happens after the transfer!
The printed transfer roll that has been collected in the rewinder of the plotter can be transferred onto the fabric in three ways.
Continuous transfer on the calender:
The entire roll of printed transfer is loaded into the calendar together with the fabric, in this way it works continuously and the entire roll of fabric will be sublimated
Continuously placed transfer onto a calender
The printed transfer roll is loaded into the calendar with the print facing upwards (visible) and an operator places the pieces of fabric on it. The various pieces of fabric of the open garment will be used to make sports or fashion clothing.
An advantage of this type of processing is to have the pieces cut in various sizes that can be used if necessary, without having to start production from scratch.
Transfer by heat press
The prints made on the transfer roll are trimmed individually and placed on top of the fabric inside the heat press.
When the fabric has been sublimated it can be packaged and finished according to production needs
Again I wrote the strengths and weaknesses of indirect sublimation printing by comparing it to direct sublimation printing.
Strengths of indirect sublimation printing.
- Fabrics with textures and not perfectly planar can be used since the transfer takes place in a calender or heat press and there is no risk of collision with the head.
- Low ink consumption as it remains more on the surface than direct sublimation printing.
- You can use fabrics with filaments in the selvedges .
- You can work with the marker, the fastest solution for packaging operations.
- You can print Lycra and stretch fabrics thanks to a particular optional of the calender that unrolls the fabric eliminating any deformation problem.
- With indirect printing you do not use the oven and therefore you will not have lamps to replace.
- The plotter is not subjected to sublimation vapors compared to direct sublimation printing with an in-line oven.
- The printing and fixing of the ink are divided into two stages, this allows you to set the plotter and calender / heat press in the best possible way , in order to improve the final result.
- Superior print quality compared to direct printing as the detail guaranteed by the coating of the paper is also greater due to the greater variety of inks that can be installed.
- Greater choice of fabrics than direct sublimation printing.
Weaknesses indirect sublimation printing
- Compared to direct printing with an in-line oven, the production cycle is divided into two phases and an operator is needed to load and unload the transfer and fabric rolls from the calender.
- Greater workspace for positioning plotter + calender or plotter + heat press
- Higher cost of the printed fabric for the use of transfer paper and sacrificial paper plus the cost of the operator who takes care of the transfer operation.
- In the case of flag printing, to obtain perfect double-sided printing, quality sublimation paper with the right thickness must be used, with direct printing this type of production is simpler and less expensive.
We have seen how sublimation works with the two different sublimation technologies, now let’s see what it takes to start an indirect sublimation printing laboratory.
What you need to start an indirect sublimation printing laboratory
If the previous paragraphs have turned on light bulbs and given you ideas, now is the time to talk about what you need to start a sublimation printing workshop.
In the meantime, a list, then let’s go into detail
- Sublimation plotter
- Sublimation ink
- Rip Print
- Sublimation paper
- Heat press
- Calender for sublimation
Let’s see them one by one
The first essential thing for indirect sublimation printing is the sublimation plotter .
Sublimation prints using an inkjet plotter.
The large format sublimation plotter is a printing plotter with sublimation inks loaded.
Take a look at the complete range of Roland Sublimation Plotters
Its functionality is identical to an eco-solvent large format plotter, with the difference that it will be designed to print exclusively transfer paper unlike eco-solvent plotters which can print dozens of materials.
It is important that the plotter is able to print tens of meters of transfer without defects, the transfer dragging must be linear to avoid the plotter blocking during printing.
Printing speed plays an important role in high runs and the plotter must be able to manage prints without banding that would be visible at the time of thermal transfer on the fabric.
Print quality must be excellent especially for applications such as fashion, fashion, and sportswear.
The ink loading system must allow a long printing autonomy to avoid interruptions while the plotter is not supervised, for example at night.
A question I often get asked is whether the sublimation plotter can only be configured with sublimation inks.
The answer is yes!
You have to dedicate a plotter to this type of production, there are no sublimation / eco-solvent configurations.
The sublimation plotter is not to be confused with the sublimation printer.
By sublimation printer, we generally mean printers of maximum A4 or A3 format dedicated to the world of objects or small personalization on fabric.
The heart of the sublimation plotter are the inks, let’s get to know them better.
Characteristics of sublimation ink
The sublimation ink is deposited by the plotter heads on the transfer paper and from this moment on it assumes a solid stage.
While the ink-laden transfer is coupled to the fabric and subjected to a heat of about 200 degrees it changes to a gaseous state, when the thermal transfer is complete, the ink resumes the solid-state in the form of colored pigment trapped in the fibers of the fabric.
Quality sublimation inks must have very specific characteristics:
- Do not clog the print head nozzles
- Vivid and brilliant coloring
- Quickly dry on the transfer paper to be rewound later
- Resistance to washing
- Certifications suitable for eco-label use
It is important to know that the sublimation inks are completely non-toxic water-based.
This feature is essential if you want to produce clothing.
Another strong point of sublimation inks, and the relative configuration of the plotter, are the spot colors.
In addition to the classic four-color process and the Cyan Light and Magenta Light colors that help to improve shades, it is possible to use spot colors to expand the chromatic gamut.
By using sublimation inks such as orange, purple, and blue, a greater range of colors can be reproduced.
You can also use fluorescent colors such as yellow and pink, especially useful in sportswear.
These two fluorescent colors combined with the rest of the inks allow you to achieve other fluorescent shades.
The black ink in sublimation printing can have different “flames” or it can tend towards a colder or warmer black and depending on the markets or uses, one or the other may be preferred.
Ink configuration and supply
The ink configuration can be in a double four-color process or with spot colors, this depends on the specific qualitative / production needs.
In general, with the dual four-color configuration, the plotter prints faster but with a reduced color, gamut compared to configurations with spot colors.
Another important aspect is the ink supply system, which can be with the classic bulk with 1-liter containers in which the ink is poured or the sealed bags that are inserted in the bulk of the plotter.
The advantage of the bags is that the ink does not come into contact with the air (which causes it to oxidize) and with the inevitable impurities due to the transfer of the ink.
Furthermore, if the plotter is not used often, the ink can create sediment in the bottom of the container which remains trapped in it, and in the long term, the sediment can reach the print heads, damaging them.
The controlled atmosphere sealed bags guarantee production continuity.
The print rip is used for the processing of your graphic file that takes place during the so-called ripping phase.
Your file is processed in a “language” that is understood by the plotter and allows correct printing in terms of layout, speed, and quality.
The printing Rip for sublimation printing must be able to manage the spot color channels, for the correct chromatic processing of the file.
A self-respecting Sublimation Rip must also have advanced features such as the ability to create a pattern with a small portion of the total file.
Here is a practical example!
If I have to make fabric for a 10-meter long sofa with a particular pattern, I don’t have to create a 10-meter long file but a pattern module that the rip will reproduce for the size I need, this function is called step & repeat.
Obviously, the file must be constructed in such a way as to allow a perfect fit between a module and the top.
A fundamental detail for the correct sublimation printing is the printing of the exact color.
In clothing, printing the color requested by the customer is the basis of success, prints that do not confirm the color approved in the estimate stage are not tolerated.
This color must also be reproduced in subsequent reprints.
Imagine the reissue of a set for a player of a football team, it must be the same as the other members of the team.
This is possible thanks to a professional rip and correct color management.
In this regard, the automatic creation of chromatic derivations by the rip is useful, i.e. starting from a single color, the rip automatically generates a matrix of colors close to the main color.
This function is widely used to print a sample to show to the customer, thus avoiding endless print tests.
Rip allows you to print an exact color and reproduce it in future runs
The automatic nesting function of the material or nesting is used to optimize the positioning of the prints to rationalize costs and production, especially in the printing of the marker.
The choice of rip is not secondary to the choice of the plotter.
The sublimation paper is the support on which the ink printed by the plotter is deposited, which will be coupled to the fabric to transfer the print.
The sublimation paper has two sides, one coated and the other not.
The function of the coating is to be receptive to the ink, therefore to trap it, and release it in a gaseous form when it is coupled to the fabric during the passage in the calendar and heat press.
Sublimation papers differ in weight and quantity of coating and if they are adhesive or not.
The type of transfer paper used therefore affects the quality of the finished product, the higher the weight the better the final result.
In practice, a paper with a lower weight printed with a lot of ink will embark on creating waves in the printing phase, while with a greater weight it will allow you to have important ink coverage without problems when printing especially at high speeds.
It is possible to choose sublimation papers with a slight adhesion.
This is very useful when printing single pieces of fabric.
When the operator places on the fabric, the adhesive transfer paper does not move and makes the transfer operations faster.
This type of paper is especially useful with the use of a heat press.
For an optimal printing result, it is advisable to carry out ad hoc color profiles especially on low-weight low-weight paper.
Sublimation heat press
The sublimation press to be suitable for sublimation must have some basic requirements:
- Have the same pressure all over the surface
- Have a uniform temperature over the entire surface
- Having the right base that allows the vapors to escape
The first two conditions, pressure and temperature, are essential to have sublimated fabrics without color differences on the surface.
The presses used for the production of prints on fabric are generally large in size from a minimum of 70 x 100 cm to a maximum of 150 x 400 cm.
They are all pneumatic, i.e. the opening and closing is managed with compressed air and a timer opens the plates at the end of the transfer.
There are models with a single lower shelf or models with double drawers.
The latter model allows you to load the second floor while the first is engaged in pressing, speeding up production which becomes as rapid as printing on a calendar with a 20 cm cylinder.
The large heat presses are three-phase and consume many kilowatts, a detail not to be overlooked when purchasing.
A difference between the presses used for Thermo transfer and those for sublimation lies in the coating of the lower floor.
The heat transfer presses have a rubber surface, while those for sublimation generally have a Nomex mat.
Calender for sublimation
The sublimation calendar can be used for two different types of processes:
- Continuous printing of the fabric roll
- Continuous and placed printing
Continuous printing on the roll is ideal for long print runs on fabrics of different compositions and texture.
To start production, the transfer roll and the fabric roll must be mounted in the calendar and both passed under the oil-heated cylinder.
Temperature and pressure are managed according to the type of fabric and transfer paper used.
Another roll that is always mounted in the calendar is the so-called martyrdom paper or sacrificial paper, it has the task of protecting the felt during the transfer.
The printing of the placed with calender is possible only if it is equipped with a longer entrance surface so that while the printed transfer paper advances, the operator has the possibility to place the fabric scraps that will be accompanied towards the hot roller and so sublimated.
This application is more practical than the heat press and very useful for those who print custom clothing.
A double drawer heat press is as fast as a 20cm cylinder calendar but requires a lot more loading and unloading work.
The calendar consumes much less electricity than the press because once the oil contained in the cylinder reaches the temperature, it maintains it, activating the internal resistances intermittently while in the heat press the resistances are always on!
Application of large format sublimation printing
Sublimation printing has applications in many fields and is an expanding technology.
I make a rundown of the main markets to which you can compete with a sublimation system
With Soft Signage we mean the printing with light fabrics for the realization of common products for visual communication such as flags, banners, exhibition stands.
Since they can print you very light and easy-to-transport fabrics, the applications are also valid for setting up scenographies, conferences, fairs.
With the use of displays, shops and points of sale can also be customized, for example, backlit prints have brighter colors than solvent-based paints.
Since polyester is a 100% recyclable fabric, the growing demand for so-called “green” materials can be exploited.
With a large format sublimation plotter it is also possible to customize sublimation gadgets .
This type of application can also be achieved with a small sublimation printer, using sheet-fed transfer paper.
There are specialized suppliers of sublimation gadgets already pre-treated and ready to be sublimated.
Fashion and Fashion
In the fashion industry it is essential to have brilliant colors and images with perfect print quality.
You can go from ready-to-wear fashion to more prestigious applications.
Unlike other non-digital technologies, sublimation allows you to have neutral fabrics and customize them if necessary even with very different productions while maintaining highly competitive costs with a high color rendering and extreme washing fastness.
For many years, the trend of interior decoration with ecosolvent plotter has been growing thanks to prints on wallpaper, vinyls for walls and films for covering furniture and various surfaces.
Sublimation completes the decoration of an interior with personalization, for example of curtains, tablecloths, upholstery for furniture, sofas and armchairs and other prints on polyester fabrics.
With sublimation it is possible to customize many parts of the house and create unique environments using, for example, rigid supports such as Croma Lux to decorate rigid surfaces such as kitchen panels, furniture, paintings and more.
This market interests us Sicilians very closely, being a splendid island, I think it is possible to find interesting market niches in the tourism and souvenir sector .
Sublimation allows you to create customized costume lines and some interesting gadgets such as beach towels, flip flops, synthetic fiber sarongs and other applications that can start from simple neutral fabric and then packaged.
This is an idea that I want to give you but which obviously deserves careful analysis before making an important purchase such as a sublimation system.
Final thoughts on sublimation printing
Sublimation printing is a growing sector that can be used to find new market niches and diversify the types of products supplied to your customers.
As I always recommend in consultancy, you must not be reckless and analyze the market and the competition well , since we are talking about investments worth thousands of euros.
Other aspects to be analyzed are electricity consumption and business skills to be developed, from file creation to fabric finishing operations and clothing packaging.
What I recommend is to be curious about this technology which in the future will be increasingly present in the laboratory of many professional printers.