As the name suggests, reactive printing means that printing dyes are processed by reactive printing and dyeing. The design elements of reactive printing are various: plants, flowers, geometric figures, English letters, and different color blocks are organically combined to express different design styles through design techniques. Such fabrics are suitable for a wide range of groups and a long time. The fabric with reactive printing has bright color, good color fastness, soft hand feel, can be washed frequently without fading, and can be used as new for a long time.
Reactive dye digital ink-jet printing is an important type of digital ink-jet printing. Digital ink-jet printing with reactive dyes can be used for printing cotton and linen fabrics, wool, silk, nylon fibers, etc. Reactive dyes are water-soluble dyes. Their reactive groups react with the reactive groups of fibers to form covalent bonds under certain reaction conditions. Compared with other kinds of printing, digital ink-jet printing with reactive dyes has bright color, comprehensive chromatogram, good levelness, and dry and wet rubbing fastness. It is the main printing process for cotton, linen, and silk fabrics. Due to the various excellent properties of reactive dyes, the proportion of digital ink-jet reactive printing in the current market is also relatively large. Reactive dye digital ink-jet printing is a multi-link and multi-disciplinary process, which involves many disciplines, such as electronic machinery, computer software, chemical engineering, chromatics, and so on.
Digital ink-jet printing is a systematic project. Its key technologies are the research and development of equipment, software, and color ink. The high-speed belt guide digital inkjet printing machine adopts 6 world-class industrial stainless steel piezoelectric nozzles made in the United States. The maximum printing speed is 40m/h (60dpi, 4 colors) and the maximum printing accuracy is 1080dpi. At the same time, it supports a variety of professional inks and fabrics and can control the size and speed of ink drops through software and hardware control technology. The industrial production of digital ink-jet printing has been truly realized.
Reactive dye digital printing requires pre-treatment and post-treatment processes. The pre-treatment and post-treatment equipment can be improved and used according to the output and production mode of each digital printing product and the actual situation of each factory or customized professional finishing equipment for small-batch processing. With the increase of sizing thickener, the surface color depth of silk and cotton fabrics increased; When sodium bicarbonate is used as an alkali agent, silk and cotton fabrics perform better in color depth and color stability; In order to obtain darker color, the cotton fabric needs more alkali and urea than silk fabric, and the amount of sodium sulfate is the same; The fixation rate of reactive dyes on cotton is lower than that on silk during steaming. According to statistics, printing products account for 11-13% of the textile production in the world, while about 58% of the printed textiles in the market are produced by round screen printing machines, 28% by flat screen printing machines, and the remaining 3% are four pattern printing, 5% are transfer printing, and 6% are produced manually. Usually, the time used for carving and sample making often accounts for more than half of the production time, so the textile ink-jet printing technology came into being. It is the latest printing high-tech developed internationally since the 1990s. It integrates electronic information, computer, machinery, and other disciplines. It is a major breakthrough in traditional printing technology. The high-tech is to input the image processed by digital technology into the computer, edit it with a cap (computer printing color separation system), and then control the ink-jet printing system by special software (RIP), so as to directly spray the special color onto the fabric to form the printed fabric required by the design. Inkjet printing is a fast, flexible, clear pattern, creative, competitive, and ecological, which conforms to the production model of small-batch and multi-variety. At present, inkjet printing technology has been applied to clothing, household textiles, wallpapers, carpets, woven ribbons, labels, flags, ties, and scarves.
The technology of digital ink-jet printing machines involves digital ink-jet printing equipment, manufacturing method, and process. It is a combination of software and hardware. The software part includes online collaborative design technology of textile patterns, and special rip control technology suitable for multi varieties of textiles, and the hardware part includes the electrical structure of a digital ink-jet printing machine. Vega high-speed digital ink-jet printing machine consists of a guide belt driven media conveying device, an ink-jet printing device, an ink supply device, a guide belt deviation correction device, a synchronous lifting device of the ink-jet printing device, a guide belt surface cleaning device, a cloth pasting device for media sticking to the guide belt, etc. Vega system adds the conversion from 4-bit RGB to 6-bit RGB format on the basis of traditional image compression technology and proposes a new effective coding and compression method for cooperative design shared patterns.
Compared with traditional printing, digital ink-jet printing has the advantages of high production process flexibility, good reproducibility, high precision, a marketing system suitable for small batch and fast delivery, and meeting the requirements of cleaner production and remote ordering. These advantages make the application of digital ink-jet printing more and more widely. The printing of knitted fabrics has developed rapidly in a short period of ten years. However, because its dimensional stability is difficult to control in the processing process, it is difficult to develop the circular screen printing of knitted fabrics, especially those containing spandex. In addition to the large dimensional plasticity of cotton knitted fabrics, their own drape weight, and the tension of the feeding frame, they are also subject to the tensile force of speed changes, and the shape and size of patterns are more difficult to control, It is more difficult to maintain the original spirit of the flower shape when encountering geometric patterns, and it is difficult to achieve satisfactory results. This must be solved by taking necessary control of the whole processing process.