Textile printing can be best described as the art and science of decorating a fabric with a colorful pattern or design. Over fifty percent of the world’s printed fabric is produced in the Far East, compared to approximately twenty percent in the US and Europe. The majority of all textiles are printed using rotary screen print machines. While this technology offers high speed and low product cost, there are many drawbacks. The trend in textile printing is for rapidly decreasing order size, forcing textile companies to print shorter runs. Rotary screen technology offers obvious benefits for long runs, but does not allow economical short run production. As the price per yard continues to decrease, traditional manufacturers are forced to respond to the changing world of textile printing. Indeed, the world of textile printing is rapidly changing. Customers are demanding a greater variety of color and design. Responding to this demand is a necessity in today’s marketplace. Printers are forced to find new and innovative ways to provide printed samples while minimizing cost and waste. This urge paved the way towards a new method of priming, what today we call the digital textile printing.
Digital Textile Printing
Digital printing technology allows customers to streamline the entire design, sampling, and production process. When it comes to true inkjet production for textiles, there are not many choices. Most of the current inkjet printers were designed for graphic arts printing on paper, not fabric. Several companies have begun to address these problems, and the future of digital printing of textiles is beginning to take shape. Over the past two years, several machine integrators have released short run production equipment using a wide variety of inkjet technology. In addition, printers with speeds up to 100 m2 / hour for direct textile printing and up to 200 m2 / hour for transfer printing are becoming available this year. Most of the machines currently being developed for ink jet textile printing are based on existing material handling systems. These printers will be capable of utilizing multiple ink chemistries and will print both knitted and woven fabrics. Though no one can predict when we will see a dramatic change from traditional to digital production, it is clear that the future of textile printing will be digital. Today’s textile marketplace demands the benefits of digital printing, the textile industry has embraced this new technology, and most importantly – digital printing machines have finally met the challenge of textile production printing.
Inkjet Printing- An Overview
There are two fundamental types of inkjet technology – Drop on Demand and Continuous Ink Jet. Both have benefits and drawbacks, depending on the construction and engineering of the print head.
Drop on Demand Technology
Drop on Demand (DOD) ink jet print heads use either a Thermal (TIJ) or Piezoelectric (PIJ) mechanism to “fire” nozzles and place droplets (drop) onto the substrate only when they are needed (on demand). Thermal Ink Jet Heads use thermal excitation to form a bubble in the ink chamber, thus force a drop of ink out of a given nozzle. Up to 85% of all print heads in the office document ink jet market are thermal, and most use water based inks. Thermal ink jet heads are inexpensive to manufacture and well-suited technology for low-volume printing. They produce high-resolution prints by using small drop size; however, the low viscosity and high temperature restrictions limit the types of chemistry that can be formulated into ink for thermal print heads. Thermal technology is sometimes referred to as “bubble-jet.” Piezoelectric (Piezo) ink jet print heads use a piezoelectric transducer to excite and warp the interior of a given ink chamber, forcing a drop of ink out of that chambers nozzle. Piezo print heads are well suited for high-volume printing, because reliability is built into the design of a print head. They also produce high-resolution prints by using small drop size; however, piezo heads allow for higher ink viscosity. Piezo print heads also allow for a wider range of ink formulations; including pigment inks formulated for textile standards of durability. With print resolution up to 720 DPI, DOD inkjet printing is now the standard in direct textile printing.
Continuous Ink Jet Technology
Continuous ink jet print (CIJ) heads use a continuous stream of ink that is broken into droplets after leaving the print nozzle. The droplets are given a charge and pass through a deflection area where they are either recycled via a “gutter” system or placed onto the substrate. The two main types of CIJ are Binary and Multi-Deflection. Binary CIJ print heads use a simple gutter and ink reclamation system to control drop placement on the substrate. As ink droplets pass through the charging area in a binary system, they are either deflected into a gutter or allowed to drop onto the substrate. Some ink jet experts claim that binary continuous ink jet is poorly adapted to process colors. As a rule, binary CIJ print heads are expensive to manufacture and maintain; thus a poor choice for reliable production printing. Multi-Deflection CIJ print heads are the newest form of CIJ technology. A multi-deflection CIJ print head uses the same basic principle as binary CIJ, but provides more drop placement control. As droplets of ink pass through charging areas in a multi-deflection head, the print system can give varying amounts of charge to the droplet. As droplets then pass through a deflection area, they can be placed on the substrate at a variety of angles. Most multi-deflection CIJ print heads have up to 5 angles of drop travel, excluding the path into a gutter system. The varying angles of drop placement provide wider substrate coverage with fewer print heads than other forms of CIJ technology.
The Progression and Advancement
|The global market for Digital Textile Printing is projected to reach a revised US$3 billion by the year 2027 after a US$230 million erosion in market value in the year 2020.|
Although digital / inkjet technology has been widely used in other markets for over 20 years; the first inkjet printer for textiles was introduced in 1991. Based on a modification of the Hertz Continuous inkjet principle, the TruColor Jet Printer from Stork was truly revolutionary. Combined with a highly purified line of reactive dyes from Zeneca, the TruColor printer provided CAD users the ability to print a pattern directly onto fabric without the need for screens. Stork’s TruColor printer opened the door for designers and print manufacturers to modify designs, colorways, and evaluate each new pattern on cotton fabric. In addition, the use of reactive dyes allowed the samples to be steamed and washed – providing a durable sample for customer review. The original TruColor Jet Printer from Stork (TCP 1122) has evolved into the TCP 4000 Series – still a popular form of inkjet sampling.
From 1991 until 1997, the TCP series was the only inkjet textile printer providing direct textile printing. Although others tried, no printer could match the color gamut and print quality of the Stork TCP 4000 Series. In 1995, ENCAD, a California ink jet integration company, identified the textile industry as a good market for their wide format ink jet printers. ENCAD was losing market share in the graphic printing market and needed to find a way to increase sales. They approached the textile industry with their 1500 TX as a sampling / short production tool. ENCAD was not widely successful, due to their limited color gamut and lack of ink durability. ENCAD’s attempt at entering the Textile market left most ink jet machine manufacturers wondering if the textile industry was ready for inkjet printing.
The global market for Digital Textile Printing is projected to reach a revised US$3 billion by the year 2027 after a US$230 million erosion in market value in the year 2020. In the post COVID-19 period, the versatile benefits of digital textile printing over conventional printing methods will help bring back growth opportunities. Digital printing offers a number of benefits over traditional printing such as efficient set-up as well as speed, cost-effectiveness, shorter lead times, improved design aesthetics, customization options, workflow efficiencies, cost reduction and flexibility.
The Breakthrough in Technology
Just when it seemed as though inkjet printing would fade away as a viable method of textile printing, a relatively unknown company made a huge breakthrough in the textile industry. Mimaki Engineering, a Japanese inkjet integration company, began marketing their JV2 series printers for textile sampling. Mimaki introduced the TX-1600, a seven color inkjet printer based on the EPSON piezo print head. The Mimaki TX-1600, capable of printing at 720 DPI, was just the second digital printer to provide high quality textile print samples with a reasonable color gamut. In addition, the TX-1600 provided roll-to-roll printing; something the Stork TCP series lacked. The result was the ability to create enough printed yardage to create finished apparel and home furnishings for showrooms and customer samples. The combination of high quality printing, increased color gamut and roll to roll printing has provided Mimaki with great success in the textile market. It is estimated that Mimaki now has an installed base of over 1,500 TX series printers. They have recently released the TX2; a second-generation textile printer with 5x increased speed and the capability of printing with two different sets of digital inks. As a result, Mimaki has emerged as the leader in inkjet textile printing and their print quality serves as the standard for future machines.
While the traditional textile manufacturers are slowly coming around and accepting digital printing technology, perhaps the fastest growing group of textile printers have no experience with traditional printing at all. This group of entrepreneurs consists of advertising groups, design companies, and even producers of complementary furnishings from adjacent industries. Many of these companies have begun experimenting with digital textile printing with great success. While their knowledge of textiles may be limited, their presence in the market should not be underestimated. Through the use of the Internet and retail organizations, several firms plan to offer custom fabrics for home furnishings, apparel, and just about any other fabric application you can imagine by the end of 2002. One of the most impressive ideas offers the ability to design and coordinate a complete room – carpets, bedding, drapery, wallcoverings, and even furniture; all with patterns and colors chosen by the end user. Another group plans to offer customized apparel that can be design and colored by the user and even viewed for fit through special 3-D body animation software. The customer can input body measurements or have a body scan performed to generate a computer simulation of their figure. Special software then takes garment design data and simulates a virtual dressing room experience. Most of these businesses are in the early stages of development, but they will most likely be a strong force in textile markets very soon.
Though no one can predict when we will see a dramatic change from traditional to digital production, it is clear that the future of textile printing will be digital. Today’s textile marketplace demands the benefits of digital printing, the industry has embraced this new technology, and to meet this demand – printers are being developed that fulfill the needs of both traditional textile printers and entrepreneurs. For a traditional printer, digital printing saves time and money and will allow them to remain competitive in a changing world of textile printing. For an entrepreneur, digital printing offers all of the benefits described above; but most importantly, the freedom of unlimited design and a true vehicle for creative ideas.