It can still be found in the carpet industry. With this technique
irregular patterns can be produced. The carpet, previously dyed with a
ground shade, is provided with coloured spots through dripping. The size
and the frequency of the coloured spots can be varied by adjusting the
overflow groove placed along the carpet width.
Ink-Jet Printing
This is another digital printing technique with its origins in paper
printing technology that is now also increasingly used in the textile
industry. In ink-jet printing, color is applied to the surface of the
substrate without variation in firing time, pressure or velocity. For
this reason it can only be applied for flat light fabrics, especially
silk
Jet Printing
Jet printing is a non-contact application system originally developed
for printing carpets, but now increasingly used in the textile sector.
The first commercial jet printing machine for carpets was the Elektrocolor, followed by the first Millitron machine. In the Millitron printing system, the injection of the dye into the substrate is accomplished by switching on and off a dye jet by means of a controlled air stream. As the carpet moves along, no parts of the machine are in contact with the face of the substrate. Air streams are used to keep continuously flowing dye jets, deflected into a catcher or drain tray. This dye is drained back to the surge tank, filtered and re-circulated. When a jet is requested to fire, the air jet is momentarily switched off, allowing the correct amount of dye to be injected into thetextile substrate. The dye is supplied in continuous mode to the main storage tank to compensate for the amount of dye consumed
Spray printing systems and first generation jet printing methods cannot be controlled to produce a pre-specified pattern. Thus the equipment must first be employed to produce a wide range of effects and only then can selections be made from these by the designer or marketing staff.
An early improvement was made by the first digital carpet printers (Chromotronic and Titan by Zimmer and Tybar Engineering, respectively). These machines are based on the so-called «drop on demand principle», namely the use of switchable electromagnetic valves placed in the dye liquor feed tubes to allow the jetting of discrete drops of dye liquor in a predetermined sequence according to the desired pattern.
In these machines, although the amount of dye applied can be digitally controlled at each point of the substrate, further penetration of the dye into the substrate is still dependent on capillary action of the fiber and fiber surface wetting forces. This can lead to problems of reproducibility (e.g. when the substrate is too wet) and means that it is still necessary to use thickeners to control the rheology of the dye liquor.
The latest improvement in jet printing of carpet and bulky fabrics is now represented by machines in which the color is injected with surgical precision deep into the face ofthe fabric without any machine parts touching the substrate. Here, the control of the quantity of liquor applied to the substrate (which may vary for example from lightweight articles to heavy quality fabrics) is achieved by varying not only the firing time but also the
pumping pressure.
This system can be likened to an injection dyeing process. The name «injection dyeing» is used as a commercial name to define the technology applied on the latest Milliken's Millitron machine. Another digital jetprinting machine commercially available is Zimmer's Chromojet. In the Chromojet system, the printing head is equipped with 512 nozzles. These are magnetically controlled and can open and close up to 400 times a second.
The carpet is accumulated into a J-box, and is then steamed and brushed. When it reaches the printing table it is stopped. The jets are mounted on a sliding frame that can itself be moved in the direction of the warp while the carpet remains stationary during the printing process.
The first commercial jet printing machine for carpets was the Elektrocolor, followed by the first Millitron machine. In the Millitron printing system, the injection of the dye into the substrate is accomplished by switching on and off a dye jet by means of a controlled air stream. As the carpet moves along, no parts of the machine are in contact with the face of the substrate. Air streams are used to keep continuously flowing dye jets, deflected into a catcher or drain tray. This dye is drained back to the surge tank, filtered and re-circulated. When a jet is requested to fire, the air jet is momentarily switched off, allowing the correct amount of dye to be injected into thetextile substrate. The dye is supplied in continuous mode to the main storage tank to compensate for the amount of dye consumed
Spray printing systems and first generation jet printing methods cannot be controlled to produce a pre-specified pattern. Thus the equipment must first be employed to produce a wide range of effects and only then can selections be made from these by the designer or marketing staff.
An early improvement was made by the first digital carpet printers (Chromotronic and Titan by Zimmer and Tybar Engineering, respectively). These machines are based on the so-called «drop on demand principle», namely the use of switchable electromagnetic valves placed in the dye liquor feed tubes to allow the jetting of discrete drops of dye liquor in a predetermined sequence according to the desired pattern.
In these machines, although the amount of dye applied can be digitally controlled at each point of the substrate, further penetration of the dye into the substrate is still dependent on capillary action of the fiber and fiber surface wetting forces. This can lead to problems of reproducibility (e.g. when the substrate is too wet) and means that it is still necessary to use thickeners to control the rheology of the dye liquor.
The latest improvement in jet printing of carpet and bulky fabrics is now represented by machines in which the color is injected with surgical precision deep into the face ofthe fabric without any machine parts touching the substrate. Here, the control of the quantity of liquor applied to the substrate (which may vary for example from lightweight articles to heavy quality fabrics) is achieved by varying not only the firing time but also the
pumping pressure.
This system can be likened to an injection dyeing process. The name «injection dyeing» is used as a commercial name to define the technology applied on the latest Milliken's Millitron machine. Another digital jetprinting machine commercially available is Zimmer's Chromojet. In the Chromojet system, the printing head is equipped with 512 nozzles. These are magnetically controlled and can open and close up to 400 times a second.
The carpet is accumulated into a J-box, and is then steamed and brushed. When it reaches the printing table it is stopped. The jets are mounted on a sliding frame that can itself be moved in the direction of the warp while the carpet remains stationary during the printing process.
Roller Printing
In roller printing, the print paste is supplied from reservoirs to
rotating copper rollers, which are engraved with the desired design.
These rollers contact a main cylinder roller that transports
the fabric. By contacting the rollers and the fabric the design is
transferred to the fabric. As many as 16 rollers can be available per
print machine, each roller imprints one repeat of the design. As the
roller spins, a doctor blade in
continuous mode scrapes the excess of paste back to the color trough. At
the end of each batch the paste reservoirs are manually emptied into
appropriate printing paste batch containers and squeezed out. The belt
and the printing gear (roller brushes or doctor blades, squeegees and
ladles) are cleaned up with water.
Rotary-Screen Printing
Rotary-screen printing machines use the same principle described
earlier, but instead of flat screens, the color is transferred to the
fabric through lightweight metal foil screens, which are made in the
form of cylinder rollers. The
fabric moves along in continuous mode under a set of cylinder screens
while at each position the print paste is automatically fed to the
inside of the screen from a tank and is then pressed through ontothe
fabric. A separate cylinder roller is required for each color in the
design.
A suction pipe leads from the paste vat to a pump, from where a printing hose leads to the squeegee (dye pipe with squeegee). From here the paste is directed inside the cylinder roller. The fill volume of this so-called printing paste input system is quite high and as a consequence the amount of paste residue that has to be removed at each color change is also fairly significant. Various systems have been introduced in order to lower the volume configuration of this equipment, which also reduces the amount of such wastes. Another possibility, which has also already been implemented in some companies, is to recover and re-use these residues for making up new recipes.
Rotary-screen printing machines are equipped with both gluing and washing devices analogous to those described earlier for flat-screen printing. The belt is washed in order to remove the residues of paste and adhesive. Not only the belt, but also the screens and the paste input systems (hoses, pipes, pumps, squeegees, etc.) have to be cleaned up at each color change
A suction pipe leads from the paste vat to a pump, from where a printing hose leads to the squeegee (dye pipe with squeegee). From here the paste is directed inside the cylinder roller. The fill volume of this so-called printing paste input system is quite high and as a consequence the amount of paste residue that has to be removed at each color change is also fairly significant. Various systems have been introduced in order to lower the volume configuration of this equipment, which also reduces the amount of such wastes. Another possibility, which has also already been implemented in some companies, is to recover and re-use these residues for making up new recipes.
Rotary-screen printing machines are equipped with both gluing and washing devices analogous to those described earlier for flat-screen printing. The belt is washed in order to remove the residues of paste and adhesive. Not only the belt, but also the screens and the paste input systems (hoses, pipes, pumps, squeegees, etc.) have to be cleaned up at each color change
Heat Transfer Printing
Approximately 7% of printed goods are printed using Heat Transfer Printing
Advantages of Transfer Printing
- High quality prints
- Fewer seconds
- Economical for short runs
- Practically pollution free
Disadvantages of Transfer Printing
- Slow
- Primarily only for polyester
Flat-Screen Printing
Flat-screen and rotary-screen printing are both characterized by the fact that the printing paste is transferred to the fabric through openings
in specially designed screens. The openings on each screen correspond
to a pattern and when the printing paste is forced through by means of a
squeegee, the desired pattern is reproduced onthe fabric. A separate
screen is made for each color in the pattern.
Flat-screen printing machines can be manual, semi-automatic or completely automatic. One type of machine, which is still commonly found in printing houses, can be described as follows.The fabric is first glued to a moving endless belt. A stationary screen at the front of the machine, is lowered onto the area that has to be printed and the printing paste is wiped with a squeegee. Afterwards the belt, withthe fabric glued on it, is advanced to the pattern-repeat point and the screen is lowered again. The printed fabric moves forward step by step and passes through a dryer. The machine prints only one color at a time. When the first color is printed on the whole length ofthe fabric, the dried fabric is ready for the second cycle and so on until the pattern is completed.
In other fully mechanized machines all the colors are printed at the same time. A number of stationary screens (from 8 to 12, but some machines are equipped with up to 24 different screens) are placed along the printing machine. The screens are simultaneously lifted, while the textile, which is glued to a moving endless rubber belt, is advanced to the pattern-repeat point. Then the screens are lowered again and the paste is squeezed through the screens ontothe fabric. The printed material moves forward one frame at each application and as it leaves the last frame it is finally dried and it is ready for fixation.
In both machines the continuous rubber belt, after pulling away the fabric, is moved downward in continuous mode over a guide roller and washed with water and rotating brushes to remove the printing paste residues and the glue, if necessary. After this, the belt is sent back to the gluing device. In some cases the glue is applied in liquid form by a squeegee, while in other machines the belts are pre-coated with thermoplastic glues. In this case thetextile is heated and then it is squeezed by a roller or simply pressed against the rubber-coated belt, causing the glue to soften and instantly adhere.
After printing, the screens and the application system are washed out. It is common practice to squeeze the color from the screens back into the printing paste mixing containers before washing them
Flat-screen printing machines can be manual, semi-automatic or completely automatic. One type of machine, which is still commonly found in printing houses, can be described as follows.The fabric is first glued to a moving endless belt. A stationary screen at the front of the machine, is lowered onto the area that has to be printed and the printing paste is wiped with a squeegee. Afterwards the belt, withthe fabric glued on it, is advanced to the pattern-repeat point and the screen is lowered again. The printed fabric moves forward step by step and passes through a dryer. The machine prints only one color at a time. When the first color is printed on the whole length ofthe fabric, the dried fabric is ready for the second cycle and so on until the pattern is completed.
In other fully mechanized machines all the colors are printed at the same time. A number of stationary screens (from 8 to 12, but some machines are equipped with up to 24 different screens) are placed along the printing machine. The screens are simultaneously lifted, while the textile, which is glued to a moving endless rubber belt, is advanced to the pattern-repeat point. Then the screens are lowered again and the paste is squeezed through the screens ontothe fabric. The printed material moves forward one frame at each application and as it leaves the last frame it is finally dried and it is ready for fixation.
In both machines the continuous rubber belt, after pulling away the fabric, is moved downward in continuous mode over a guide roller and washed with water and rotating brushes to remove the printing paste residues and the glue, if necessary. After this, the belt is sent back to the gluing device. In some cases the glue is applied in liquid form by a squeegee, while in other machines the belts are pre-coated with thermoplastic glues. In this case thetextile is heated and then it is squeezed by a roller or simply pressed against the rubber-coated belt, causing the glue to soften and instantly adhere.
After printing, the screens and the application system are washed out. It is common practice to squeeze the color from the screens back into the printing paste mixing containers before washing them
Tie and Dye
Patan Patola of Gujarat is the most extraordinary woven sarees anywhere
in the world. It is only in Bali, Indonesia that this type of weave is
created. The technique involved is that both the warp and the weft
threads are tied in areas where the original is to be retained and then
dyed. They continue to tie the threads from the lighter color to the
darker color until the final patter is dyed on to the un-woven thread.
After this both tied and dyed weft and warp threads are woven and the
design emerges. This is known as patola. Internationally this technique
is known as ikat, an Indonesian word. The finest example of ikat known
in the world is the patola of Patan, which is the double ikat, where
the warp and weft are tied and dyed before they are woven. The pattern
emerges as the warp is laid out and then gets brilliantly delineated
when the weft is thrown across.
Tenganan in Bali is the only other centre where double ikat is still practiced. Salvi communities, who weave the patola in Patan, have perfected this technique into a fine art.
The warp for the border and the body are prepared separately. The warp is then stretched in a narrow long street using rods to stretch the threads. The pattern to be created is marked by using powdered charcoal mixed in water. The weft is prepared by wrapping it around two rods, which are inserted in to a beam stretched according to the required width. Inserting thick twisted cotton threads between them separates the groups of weft. The pattern is then tied. First those sections, which are remaining white, are tied, since the design is outline in the base color. The main pattern color emerges during this process. The final dye bath is the main background color, which more often than not, is red. Each color requires that the tied sections are untied and threads to be protected are tied and then dyed. This process is painstaking and great precision is required from the very beginning, when the warp and the weft are prepared, and when the warp threads are laid.
The dyed warp threads are once again stretched to their entire length, which is normally 20 yards, needed for these sarees. The warp for the borders is attached at this stage and the entire warp of the saree is then tied to the rods, rolled and stored ready for weaving. This is then mounted on the simple single harness loom and the weft threads are reeled into the shuttle bobbins. The beam is placed at an angle with one side raised higher. The weft is thrown across and is carefully adjusted often with the use of a long needle so that the patterns synchronize and solid color emerges. So the patterns are based on a square grid, the lines are never distinct, causing a slight haziness, giving the impression of viewing the pattern through flowing water.
Patan used to export patolas from ancient times to the Far East. In Cambodia, Thailand and Indonesia the patola played an important part in rituals and ceremonies and became an integral part of their lives. A large scarf or kerchief with the line motif was a popular item, which was sent out from Multan to Java. Since Cambay, todays Khambhat, was another port from which patolas were exported, the name Cambay became associated with them. Some of the motifs drawn from the repertoire of these countries were absorbed into the designs woven on the sarees for local use.
The sarees have patterns like the pan bhat, leaf pattern, the nari-kunjar-jhar, lady, elephant, enclosed in a border or a jal, trellis work pattern. Chhabadi bhat, basket design, chowkdi bhat, square or lozenges, pattern with flowers in each corner, ratan chowk bhat, the jewelled square, raas bhat, the circular dance design, vohra gaji bhat, the design woven for the Vohra community, and many others.
Today only three families of Salvis continue this tradition in Patan. As a result of a training centre started by the Khadi and Village Industries Board in the late fifties, single ikat sarees are being woven in Rajkot also.
Ikat weaving is done in Andhra Pradesh and Orissa. In Pochampalli, Andhra Pradesh, it is known as pagdu bandha baddabhasi or chilka. The finer tie and dye patterns earlier woven in Chirala were woven in geometric patterns, known as telia-rumal. The origin of this style is not known; some trace it to Gujarat, others to Orissa. Yet another possibility is that it might have been developed in Jalna, since the fishermen of the coast used the rumals. In rural areas people still use the rumal as turban and as an upper cloth called baddabhasi. The telia rumal used to be exported to Aden in large quantities in the early 19th century and were then distributed to the Gulf countries and Africa.
Pochampalli began the production of these rumals as late as the beginning of the last century and began to export them to Iran and the Gulf. The Second World War disrupted the trade causing difficulties to the weavers. In 1955-56, Pochampalli was a poor isolated village with not even a road. Kamaladevi Chattopadhyay, who was the Chairman of the All India Handicrafts Board, went by jeep to Pochampalli. She persuaded the weavers to weave the first cotton saree of 60 counts, which proved to be very popular and the weaver seized the opportunity to begin producing sarees. Later the Board sent two weavers to Varanasi to study silk weaving and this resulted in the production of ikat work silk sarees, for which the demand has been growing steadily. Today Pochampalli is a prosperous village and a few master weavers are also copying the Patan patola.
The weaving of ikat furnishing is now done in the entire Nalgonda district and involves nearly 18,000 looms. Orissa has a distinctive style of ikat known as bandha. In this tradition the single ikat is worked in the warp and the borders are prepared separately. The Sambalpur Vachitraouri sarees has an extra warp pattern on the body and a Hand-Printed, Dyed and Painted Fabrics extra warp pattern on the pallu, while the shkarpara designs of squares of different colors-white, red and black- are in double ikat. The famous silk ikat sarees of Navapatan combine woven patterns on the border and pallu. They also wove calligraphic ikat shawls with verses from Geeta Govinda, which were offered to Lord Jagannath at Puri.
Tenganan in Bali is the only other centre where double ikat is still practiced. Salvi communities, who weave the patola in Patan, have perfected this technique into a fine art.
The warp for the border and the body are prepared separately. The warp is then stretched in a narrow long street using rods to stretch the threads. The pattern to be created is marked by using powdered charcoal mixed in water. The weft is prepared by wrapping it around two rods, which are inserted in to a beam stretched according to the required width. Inserting thick twisted cotton threads between them separates the groups of weft. The pattern is then tied. First those sections, which are remaining white, are tied, since the design is outline in the base color. The main pattern color emerges during this process. The final dye bath is the main background color, which more often than not, is red. Each color requires that the tied sections are untied and threads to be protected are tied and then dyed. This process is painstaking and great precision is required from the very beginning, when the warp and the weft are prepared, and when the warp threads are laid.
The dyed warp threads are once again stretched to their entire length, which is normally 20 yards, needed for these sarees. The warp for the borders is attached at this stage and the entire warp of the saree is then tied to the rods, rolled and stored ready for weaving. This is then mounted on the simple single harness loom and the weft threads are reeled into the shuttle bobbins. The beam is placed at an angle with one side raised higher. The weft is thrown across and is carefully adjusted often with the use of a long needle so that the patterns synchronize and solid color emerges. So the patterns are based on a square grid, the lines are never distinct, causing a slight haziness, giving the impression of viewing the pattern through flowing water.
Patan used to export patolas from ancient times to the Far East. In Cambodia, Thailand and Indonesia the patola played an important part in rituals and ceremonies and became an integral part of their lives. A large scarf or kerchief with the line motif was a popular item, which was sent out from Multan to Java. Since Cambay, todays Khambhat, was another port from which patolas were exported, the name Cambay became associated with them. Some of the motifs drawn from the repertoire of these countries were absorbed into the designs woven on the sarees for local use.
The sarees have patterns like the pan bhat, leaf pattern, the nari-kunjar-jhar, lady, elephant, enclosed in a border or a jal, trellis work pattern. Chhabadi bhat, basket design, chowkdi bhat, square or lozenges, pattern with flowers in each corner, ratan chowk bhat, the jewelled square, raas bhat, the circular dance design, vohra gaji bhat, the design woven for the Vohra community, and many others.
Today only three families of Salvis continue this tradition in Patan. As a result of a training centre started by the Khadi and Village Industries Board in the late fifties, single ikat sarees are being woven in Rajkot also.
Ikat weaving is done in Andhra Pradesh and Orissa. In Pochampalli, Andhra Pradesh, it is known as pagdu bandha baddabhasi or chilka. The finer tie and dye patterns earlier woven in Chirala were woven in geometric patterns, known as telia-rumal. The origin of this style is not known; some trace it to Gujarat, others to Orissa. Yet another possibility is that it might have been developed in Jalna, since the fishermen of the coast used the rumals. In rural areas people still use the rumal as turban and as an upper cloth called baddabhasi. The telia rumal used to be exported to Aden in large quantities in the early 19th century and were then distributed to the Gulf countries and Africa.
Pochampalli began the production of these rumals as late as the beginning of the last century and began to export them to Iran and the Gulf. The Second World War disrupted the trade causing difficulties to the weavers. In 1955-56, Pochampalli was a poor isolated village with not even a road. Kamaladevi Chattopadhyay, who was the Chairman of the All India Handicrafts Board, went by jeep to Pochampalli. She persuaded the weavers to weave the first cotton saree of 60 counts, which proved to be very popular and the weaver seized the opportunity to begin producing sarees. Later the Board sent two weavers to Varanasi to study silk weaving and this resulted in the production of ikat work silk sarees, for which the demand has been growing steadily. Today Pochampalli is a prosperous village and a few master weavers are also copying the Patan patola.
The weaving of ikat furnishing is now done in the entire Nalgonda district and involves nearly 18,000 looms. Orissa has a distinctive style of ikat known as bandha. In this tradition the single ikat is worked in the warp and the borders are prepared separately. The Sambalpur Vachitraouri sarees has an extra warp pattern on the body and a Hand-Printed, Dyed and Painted Fabrics extra warp pattern on the pallu, while the shkarpara designs of squares of different colors-white, red and black- are in double ikat. The famous silk ikat sarees of Navapatan combine woven patterns on the border and pallu. They also wove calligraphic ikat shawls with verses from Geeta Govinda, which were offered to Lord Jagannath at Puri.
Discharge Printing
Discharge Printing is also called Extract Printing. This is a method of
applying a design to dyed fabric by printing a color-destroying agent,
such as chlorine or hydrosulfite, to bleach out a white or light
pattern on the darker coloured ground. In color-discharge printing, a
dye impervious to the bleaching agent is combined with it, producing a
colored design instead of white on the dyed ground.
Discharge printing has been around for decades. But only in the past 7-8 years screen printers in the industry have recognized it seriously. In the early years of discharge printing, the finished discharge print needed to be steamed during the drying process. This discouraged the use of discharge systems in the finished garment arena. The newly developed discharge ink systems are chemically reactive and dont need to be steam-neutralized. This advancement opened the door to discharge printing for the average screen printer.
Discharge printing has the ability to make bright, opaque colors on dark fabrics with a soft hand. Years ago the idea of opaque colors on dark fabrics and soft hand couldnt co-exist.
Successful light-on-dark printing with plastisol relies on increased pigment loads, fillers and other additives to block out the color of the garment. Discharge inks modify the garment color by removing the garment color and replacing it with the new ink color. In simple terms, the discharge ink "bleaches" out the dye in the garment, thus allowing the pigment in the ink to absorb into the shirt fibers.
The real magic of discharge printing can be witnessed when printing four-color process on black 100% cotton shirts. The print before curing appears very transparent. One can barely see the print until the garment exits the oven chamber, where the results can be quite remarkable: bright, vivid colors with a soft hand.
The graphics on the casino gaming tables are printed with discharge inks to avoid the interference of the printed line with the roll of the dice. If the ink on these tables were printed with plastisol, the ink film (because it is a surface print) would change the speed and direction of the dice, thus changing the way the dice land. Discharge ink, on the other hand, provides a dyed-in-the-fabric result, keeping the playing surface smooth. The decrease in the production time is the biggest bonus of all. The fact that you can skip flash curing completely saves hours of production time and eliminates registration problems between the designs colors and the white printer under base used in normal printing on blacks.
Discharge printing has been around for decades. But only in the past 7-8 years screen printers in the industry have recognized it seriously. In the early years of discharge printing, the finished discharge print needed to be steamed during the drying process. This discouraged the use of discharge systems in the finished garment arena. The newly developed discharge ink systems are chemically reactive and dont need to be steam-neutralized. This advancement opened the door to discharge printing for the average screen printer.
Discharge printing has the ability to make bright, opaque colors on dark fabrics with a soft hand. Years ago the idea of opaque colors on dark fabrics and soft hand couldnt co-exist.
Successful light-on-dark printing with plastisol relies on increased pigment loads, fillers and other additives to block out the color of the garment. Discharge inks modify the garment color by removing the garment color and replacing it with the new ink color. In simple terms, the discharge ink "bleaches" out the dye in the garment, thus allowing the pigment in the ink to absorb into the shirt fibers.
The real magic of discharge printing can be witnessed when printing four-color process on black 100% cotton shirts. The print before curing appears very transparent. One can barely see the print until the garment exits the oven chamber, where the results can be quite remarkable: bright, vivid colors with a soft hand.
The graphics on the casino gaming tables are printed with discharge inks to avoid the interference of the printed line with the roll of the dice. If the ink on these tables were printed with plastisol, the ink film (because it is a surface print) would change the speed and direction of the dice, thus changing the way the dice land. Discharge ink, on the other hand, provides a dyed-in-the-fabric result, keeping the playing surface smooth. The decrease in the production time is the biggest bonus of all. The fact that you can skip flash curing completely saves hours of production time and eliminates registration problems between the designs colors and the white printer under base used in normal printing on blacks.
- However, flash curing can be used in conjunction with discharge printing when printing discharge as an under base.Cleaner and more transparent inks can also be printed onto dark garments with the help of discharge additives. Early discharge additives were designed only for water base inks, but plastisol additives are available.
Characteristics that indicate a Garment will work with Discharge Ink
- The garment has to be made of natural fibers (100% cotton)
- The dye used in the garment must be dischargeable. The best results are achieved with garments that are 100% cotton and dyed with a reactive dye.
- The garment should not have been over dyed (when fabric is re-dyed to another color). This often happens because of a shortage of a certain fabric color or, in many cases, because quality control rejected the fabric color. These rejected colors are then over dyed with a black dye, which will bring nightmares to life when trying to use discharge inks. The discharge ink might discharge the black dye - only to reveal a phantom color underneath
Points to be Noted
- Do not to overlap your separations if you want to print clean spot colors. Butt-to-butt separations are ideal for most discharge printing.
- Work with a negative background and allow the dark background of the garment to show through. If you choose to overlap the color separations, overlap the primary colors - red, blue and yellow - to achieve secondary and tertiary colors within the design.
- To create the screen for under-basing with discharge ink, sandwich all the color separations together (make a contact sheet or a mask) to allow the discharge ink to be printed under all subsequent colors. (Suitable plastisols can be printed over clear discharge bases. Consult your ink manufacturer for compatibility with plastisol.)
- Discharge printing is frequently used for all-over prints because of its soft hand.
Batik
The term "Batik" is an Indonesian-Malay word
Batik has come to be used as a generic term which refers to the process of dyeing fabric by making use of a resist technique; covering areas of cloth with a dye-resistant substance to prevent them absorbing colors. The technique is thought to be over a thousand years old and historical evidence demonstrates that cloth decorated with this resist technique was in use in the early centuries AD in Africa, the Middle East and in several places in Asia. Although there is no sure explanation as to where batik first was "invented", many observers believe that it was brought to Asia by travelers from the Indian subcontinent.
Despite the fact that batik may have originated elsewhere, most observers believe that batik has reached its highest artistic expression in Indonesia, particularly in Java. The art of Batik was later spread to the rest of the Indonesian archipelago and to the Malay Peninsula where the popularity of the cloth led to the establishment of many other production centers. Batik has become a very central means of artistic expression for many of the areas of Asia and a deeply integrated facet of Asian culture.
Much of the popularity of Batik can be tied to the fact that the batik technique offers immense possibilities for artistic freedom as patterns are applied by actual drawing rather than by weaving with thread.
Another factor in its popularity is the fact that it is so durable. The colors in Batik are much more resistant to wear than those of painted or printed fabrics because the cloth is completely immersed in dye and the areas not protected by resist are allowed to absorb hues to the extent that the colors will not easily fade.
Because of the popularity of batik designs, many batik patterns are used in a wide variety of fabrics. Many fabrics are called batik although they were not made in the resist method. Most purists believe that such cloth has a batik like design but is not true batik which is confined to fabrics made through the application of the originally conceived Javanese methods of resist dyeing.
Modern designers in Indonesia, Malaysia and to a lesser extent Thailand, the Philippines and elsewhere often use batik design elements and often the actual batik clothe in their clothing and accessories. Although most batik fabric is now decorated and tailored by machine, there still remains a considerable market for high-quality, hand-made batik.
Batik has come to be used as a generic term which refers to the process of dyeing fabric by making use of a resist technique; covering areas of cloth with a dye-resistant substance to prevent them absorbing colors. The technique is thought to be over a thousand years old and historical evidence demonstrates that cloth decorated with this resist technique was in use in the early centuries AD in Africa, the Middle East and in several places in Asia. Although there is no sure explanation as to where batik first was "invented", many observers believe that it was brought to Asia by travelers from the Indian subcontinent.
Despite the fact that batik may have originated elsewhere, most observers believe that batik has reached its highest artistic expression in Indonesia, particularly in Java. The art of Batik was later spread to the rest of the Indonesian archipelago and to the Malay Peninsula where the popularity of the cloth led to the establishment of many other production centers. Batik has become a very central means of artistic expression for many of the areas of Asia and a deeply integrated facet of Asian culture.
Much of the popularity of Batik can be tied to the fact that the batik technique offers immense possibilities for artistic freedom as patterns are applied by actual drawing rather than by weaving with thread.
Another factor in its popularity is the fact that it is so durable. The colors in Batik are much more resistant to wear than those of painted or printed fabrics because the cloth is completely immersed in dye and the areas not protected by resist are allowed to absorb hues to the extent that the colors will not easily fade.
Because of the popularity of batik designs, many batik patterns are used in a wide variety of fabrics. Many fabrics are called batik although they were not made in the resist method. Most purists believe that such cloth has a batik like design but is not true batik which is confined to fabrics made through the application of the originally conceived Javanese methods of resist dyeing.
Modern designers in Indonesia, Malaysia and to a lesser extent Thailand, the Philippines and elsewhere often use batik design elements and often the actual batik clothe in their clothing and accessories. Although most batik fabric is now decorated and tailored by machine, there still remains a considerable market for high-quality, hand-made batik.
Kalamkari Printing
The kalamkari, handpainted cloths of Sri Kalahasti, Andra Pradesh, works
of art drawn entirely by hand, were originally created predominantly
for the temples as narrative murals.
- These murals tell the stories of the great Hindu epics in picture form. Earlier this century, Christian missionaries commissioned artists to create murals telling the story of Christ.In addition to the epic murals, the Tree of Life theme is very popular and comes in many forms. Artists are also branching out and using the medium for their purpose.
- Kalamkari is an exquisite ancient craft of painted and printed
fabrics. It derives its name from Kalam meaning Pen, and Kari meaning
work, literally Pen-work. It includes hand painting as well as block
printing with vegetable dyes. Kalamkari art has evolved through trial
and error over the last 3000 years. Techniques of craftsmanship in
Kalamkari were handed down within the families from generation to
generation.The Kalamkari art of painting undergoes a laborious, slow process
of resist - dyeing and hand printing. Many stages have to be undergone
before the final results are achieved. Unlike other styles of painting,
Kalamkari painting demands a lot of treatment before and after the
painting is completed on the cotton fabric. Depending on the treatment
of cloth, or quality of the mordant, the colors change accordingly.
Every step from soaking of the cloth, to sketching the outlines to
washing and drying the cloth, is done carefully and correctly.
The world over, people are turning away from dangerous chemical dyes. The harmless, naturally dyed fabrics is used for Kalamkari paintings. The artists believe in using natural dyes, extracted from bark, flower and root. One would be stunned to know that the colour red is obtained by using the Indian madder root, yellow from the pomegranate seed or even mango bark, and black from myrobalam fruit. No chemical dyes are used is producing kalamkari colours.
The process used for both schools of Kalamkari painting is more or less the same. The only major difference is that Srikalahasti paintings depend entirely on the brush-like pen whereas the Masulipatnam style uses block-printing procedures. The process done in Srikalahasti is more tedious. The cloth is treated and washed twice, and is painted with alum for two to three times.
Stages
- Whitening the cloth by immersing in a solution of goat or cow dung and letting it dry in the Sun for a few days.
- The cloth is then treated in Myrobalan solution. Ripe fruits are used in Masulipatnam, raw ones in Srikalahasti. Milk is then added to the solution to prevent the colour from spreading in the next step.
- Then iron acetate solution is filled in, either for solid spaces or as outlines, with a brush-pen in Srikalahasti, and wooden blocks in Masulipatnam.
- All the areas meant to be red are painted or printed over with the alum solution as a mordant. Mordant is a substance that fixes the natural dye on the material.
- After applying alum, the cloth is kept for at least 24 hours. Then the excess mordant is removed by washing the cloth under flowing water.
- The dyeing is done for the red colour by boiling with the red coloring materials.
- All the portions that are not to be blue are covered with wax.
- The waxed cloth is immersed in indigo solution. In Srikalahasti, the blue is painted with the kalam. Then the wax is removed by boiling the cloth in water.
- The yellow is painted on to produce yellow and green.
- The cloth is finally washed again and dried before the final colours emerge
Screen Printing
Screen-printing is the most flexible printing process. It can be used to
print on a wide variety of substrates, including paper, paperboard,
plastics, glass, metals, fabrics, and many other materials including
paper, plastics, glass, metals, nylon and cotton. Some common products from
the screen-printing industry include posters, labels, decals, signage,
and all types of textiles and electronic circuit boards. The advantage
of screen-printing over other print processes is that the press can
print on substrates of any shape, thickness and size.
An important characteristic of screen-printing is that a greater thickness of ink can be applied to the substrate as compared to the other printing techniques. This allows for various interesting effects that cannot be achieved through the other printing methods. Because of the simplicity of the application process, a wider range of inks and dyes are available for use in screen-printing than for use in any other printing process.
Utilization of screen printing presses has begun to increase because production rates have improved. This has been a result of the development of the automated and rotaryscreen printing press, improved dryers, and U.V. curable ink. The major chemicals used in screen-printing include screen emulsions, inks, and solvents, surfactants, caustics and oxidizers used in screen reclamation
Overview of the Screen Printing Process Screen-printing consists of three elements
Many factors such as composition, size and form, angle, pressure, and speed of the blade (squeegee) determine the quality of the impression made by the squeegee. At one time most blades were made from rubber, which, however, had a tendency to warp and distort. While blades continue to be made from rubber such as neoprene, most of them are now made from polyurethane, which can produce as many as 25,000 impressions without significant degradation of the image.
If the item is to be printed on a manual or automatic screen press the printed product will be placed on a conveyor belt, which carries the item into the drying oven or through the UV curing system. Rotary screen presses feed the material through the drying or curing system automatically. Air-drying of certain inks, though rare in the industry, is still sometimes utilized.
The rate of screen-printing production was once dictated by the drying rate of the screen print inks. As a result of improvements and innovations in the printing technology, the production rate has greatly increased. Some specific innovations, which affected the production rate and have also increased screen press popularity include:
Once the artwork is transferred to a positive image that will be chemically processed onto the screen fabric (applying the emulsion or stencil) and eventually mounted onto a screen frame that is then attached to the printing press and production begins
An important characteristic of screen-printing is that a greater thickness of ink can be applied to the substrate as compared to the other printing techniques. This allows for various interesting effects that cannot be achieved through the other printing methods. Because of the simplicity of the application process, a wider range of inks and dyes are available for use in screen-printing than for use in any other printing process.
Utilization of screen printing presses has begun to increase because production rates have improved. This has been a result of the development of the automated and rotaryscreen printing press, improved dryers, and U.V. curable ink. The major chemicals used in screen-printing include screen emulsions, inks, and solvents, surfactants, caustics and oxidizers used in screen reclamation
Overview of the Screen Printing Process Screen-printing consists of three elements
- The screen which is the image carrier
- The squeegee
- Ink
Many factors such as composition, size and form, angle, pressure, and speed of the blade (squeegee) determine the quality of the impression made by the squeegee. At one time most blades were made from rubber, which, however, had a tendency to warp and distort. While blades continue to be made from rubber such as neoprene, most of them are now made from polyurethane, which can produce as many as 25,000 impressions without significant degradation of the image.
If the item is to be printed on a manual or automatic screen press the printed product will be placed on a conveyor belt, which carries the item into the drying oven or through the UV curing system. Rotary screen presses feed the material through the drying or curing system automatically. Air-drying of certain inks, though rare in the industry, is still sometimes utilized.
The rate of screen-printing production was once dictated by the drying rate of the screen print inks. As a result of improvements and innovations in the printing technology, the production rate has greatly increased. Some specific innovations, which affected the production rate and have also increased screen press popularity include:
- Development of automatic presses versus hand operated presses, which have comparatively slow production time.
- Improved drying systems, which significantly improve production rate.
- Development and improvement of U.V. curable ink technologies
- Development of the rotary screen press, which allows continuous operation of the press. This is one of the recent technology developments.
Screen Preparation
Screen (or image transfer) preparation includes a number of steps. First the customer provides the screen printer with objects, photographs, text, ideas, or concepts of what they wish to have printed. The printer must then transfer a "picture" of the artwork (also called "copy") to be printed into an "image" (a picture on film) which can then be processed and eventually used to prepare the screen stencil.Once the artwork is transferred to a positive image that will be chemically processed onto the screen fabric (applying the emulsion or stencil) and eventually mounted onto a screen frame that is then attached to the printing press and production begins
Fabric Block Printing
Block printing is a special form of printing first developed in China.
The earliest known example with an actual date is a copy of the Diamond
Sutra from 868 A.D (currently in the British Museum), though the
practice of block printing is probably about two thousand years old.
The first step in block printing is the production of the original document. This is laid on a large, smooth wooden block and fixed into place, reversed. Next, craftsmen of various skill levels, ranging from master carvers for the fine work to less talented artisans for cheaper blocks or less important sections, carve the original painted, drawn or written image into the block of wood. The block can now be covered with ink and used in a press to create duplicates of the original.
In some ways block printing is superior to cast type or moveable type -- for a language such as Chinese which has a very broad character set, block prints are much cheaper to produce for the initial run. The process also allows greater artistic freedom, such as the easy inclusion of pictures and diagrams. However, printing blocks are not very durable, and deteriorate very rapidly with use, requiring constant replacement that limits the possibility of large-scale print runs. Printing blocks can, however, be made from a variety of materials such as wood, linoleum, rubber, or even potatoes.
Dhamadka a village in Gujarat has many printers using mostly madder root for printing red color, rusty iron solution for black color and indigo for blue color. These fabrics are known as Ajrakh. The designs made by block printing are geometric. Many states have block-printing workshops using chemical dyes. However there are only small pockets of areas still using natural dyeing with age-old recipes and local plant material.
In Rajasthan, hand-woven cotton is printed with dye and then over printed with a mud compound used as a resist. When the mud dries the entire fabric is dyed in an Indigo bath. The areas covered with mud retain the red design while blue penetrates the remainder. The twodesigns on sale at this stall were called "young womans cloth" and "old womans cloth."
Masuliputnam in Andhra Pradesh is the main centre of block printing where the fabric is known as Kalamkari. The cloth used generally is mill made cotton, which is first bleached with cow dung and placed in the sun. The next step is to soak the cloth in a mixture of Myrobalan and milk. The Myrobalan contains tannic acid and acts as a mordant helping the dyestuffs to bond with the fibre. The buffalo milk, having high fat content, helps prevent the dye from running. Then the black outline is printed using a solution made with rusty iron soaked in sugar water and bran for several weeks. When the solution comes in contact with the myrobalan it turns black. The next step is printing on another mordant, alum.
This bonds the red dye, Madder Root, after boiling, to the areas that receive the alum. These steps continue until all colours have been printed or brushed on. It is crucial to have a good water supply for washing after printing. It takes weeks to complete all these steps.
The first step in block printing is the production of the original document. This is laid on a large, smooth wooden block and fixed into place, reversed. Next, craftsmen of various skill levels, ranging from master carvers for the fine work to less talented artisans for cheaper blocks or less important sections, carve the original painted, drawn or written image into the block of wood. The block can now be covered with ink and used in a press to create duplicates of the original.
In some ways block printing is superior to cast type or moveable type -- for a language such as Chinese which has a very broad character set, block prints are much cheaper to produce for the initial run. The process also allows greater artistic freedom, such as the easy inclusion of pictures and diagrams. However, printing blocks are not very durable, and deteriorate very rapidly with use, requiring constant replacement that limits the possibility of large-scale print runs. Printing blocks can, however, be made from a variety of materials such as wood, linoleum, rubber, or even potatoes.
Dhamadka a village in Gujarat has many printers using mostly madder root for printing red color, rusty iron solution for black color and indigo for blue color. These fabrics are known as Ajrakh. The designs made by block printing are geometric. Many states have block-printing workshops using chemical dyes. However there are only small pockets of areas still using natural dyeing with age-old recipes and local plant material.
In Rajasthan, hand-woven cotton is printed with dye and then over printed with a mud compound used as a resist. When the mud dries the entire fabric is dyed in an Indigo bath. The areas covered with mud retain the red design while blue penetrates the remainder. The twodesigns on sale at this stall were called "young womans cloth" and "old womans cloth."
Masuliputnam in Andhra Pradesh is the main centre of block printing where the fabric is known as Kalamkari. The cloth used generally is mill made cotton, which is first bleached with cow dung and placed in the sun. The next step is to soak the cloth in a mixture of Myrobalan and milk. The Myrobalan contains tannic acid and acts as a mordant helping the dyestuffs to bond with the fibre. The buffalo milk, having high fat content, helps prevent the dye from running. Then the black outline is printed using a solution made with rusty iron soaked in sugar water and bran for several weeks. When the solution comes in contact with the myrobalan it turns black. The next step is printing on another mordant, alum.
This bonds the red dye, Madder Root, after boiling, to the areas that receive the alum. These steps continue until all colours have been printed or brushed on. It is crucial to have a good water supply for washing after printing. It takes weeks to complete all these steps.
Origins of Printing
Woodblock printing is a technique for printing text, images or patterns
used widely throughout East Asia and probably originating in China in
antiquity as a method of printing on textiles and later paper. As a
method of printing on cloth, the earliest surviving examples from China
date to before 220, and from Egypt to the 4th century.
Textile printing was known in Europe, via the Islamic world, from about the 12th century, and widely used. However the European dyes tended to run, which restricted the use of printed patterns. Fairly large and ambitious designs were printed for decorative purposes such as wall-hangings and lectern-cloths, where this was less of a problem as they did not need washing. When paper became common, the technology was rapidly used on that for woodcut prints. Superior cloth was also imported from Islamic countries, but this was much more expensive. The Incas of Peru, Chile and Mexico also practiced textile printing previous to the Spanish Invasion in 1519; but, owing to the imperfect character of their records before that date, it is impossible to say whether they discovered the art for themselves, or, in some way, learned its principles from the Asiatics. During the latter half of the 17th century the French brought directly by sea, from their colonies on the east coast of India, samples of Indian blue and white resist prints, and along with them, particulars of the processes by which they had been produced, which produced washable fabrics.
Textile printing was known in Europe, via the Islamic world, from about the 12th century, and widely used. However the European dyes tended to run, which restricted the use of printed patterns. Fairly large and ambitious designs were printed for decorative purposes such as wall-hangings and lectern-cloths, where this was less of a problem as they did not need washing. When paper became common, the technology was rapidly used on that for woodcut prints. Superior cloth was also imported from Islamic countries, but this was much more expensive. The Incas of Peru, Chile and Mexico also practiced textile printing previous to the Spanish Invasion in 1519; but, owing to the imperfect character of their records before that date, it is impossible to say whether they discovered the art for themselves, or, in some way, learned its principles from the Asiatics. During the latter half of the 17th century the French brought directly by sea, from their colonies on the east coast of India, samples of Indian blue and white resist prints, and along with them, particulars of the processes by which they had been produced, which produced washable fabrics.
Jet Printing
Jet printing may be defined as a process by which the desired pattern
with its individual colors is built up by projecting tiny drops of 'ink'
(special dye liquors) of different colors, in predetermined
micro-arrays (pixels), onto the substrate surface. In all true jet
printing systems the ink is projected onto the surface as a controlled
series of drops. Usually a set of inks is used consisting of at least
three or four primary colors, namely cyan (turquoise), magenta, yellow
and optionally black, the so-called CMYK inks. As most ink-jet printers
were originally designed for paper printing, the terms encountered in,
for example, technical specifications are more related to those used in
the reprographics industry than to those that atextile printer would
normally employ. Thus reference is usually made to inks rather than dye
solutions, pigment dispersions or print pastes. Similarly print
resolution is usually defined as dots per inch(dpi) or lines per
inch(lpi).
In the field of textiles ink-jet printing is fundamentally different from that of all other techniques, not only because of the non-contact mechanics of the print head but also in the means by which the individual colors of a design are produced. A great deal of computation is necessary to produce each of the millions of pixels in a design and this continues for as long as the machine is printing the fabric. In the past printing machines were adjusted entirely by mechanical methods using the operator's experience and judgment, and although modern impact printing machines may be fitted with more refined feedback devices, these are considerably less sophisticated when compared with the electronic control of jet printers.
In printing, wooden blocks, stencils, engraved plates, rollers, or silkscreens are used to place colors on the fabric. Colorants used in printing contain dyes thickened to prevent the color from spreading by capillary attraction beyond the limits of the pattern or design.
In the field of textiles ink-jet printing is fundamentally different from that of all other techniques, not only because of the non-contact mechanics of the print head but also in the means by which the individual colors of a design are produced. A great deal of computation is necessary to produce each of the millions of pixels in a design and this continues for as long as the machine is printing the fabric. In the past printing machines were adjusted entirely by mechanical methods using the operator's experience and judgment, and although modern impact printing machines may be fitted with more refined feedback devices, these are considerably less sophisticated when compared with the electronic control of jet printers.
In printing, wooden blocks, stencils, engraved plates, rollers, or silkscreens are used to place colors on the fabric. Colorants used in printing contain dyes thickened to prevent the color from spreading by capillary attraction beyond the limits of the pattern or design.
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