With the acceleration of printing digitization, new technologies such as digital printing cTP are in full swing. Has become the irreversible mainstream development technology of today's printing. The printability of digital printing is also significantly different from traditional printing. New requirements are placed on printing materials and printing technology for printing equipment. In order to achieve good printing quality and high-speed production. The research and development of digital printing materials, especially digital printing inks, are even more important. After several years of development, digital printing ink technology has matured. However, the high price of digital printing ink is still the bottleneck restricting the development of digital printing. [NextPage] Cross Trainer,Elliptical Machine,Elliptical Cross Trainer,Body Power Elliptical Zhejiang Kingdom Sports Co.,Ltd. , https://www.zjkingdomsports.com
Digital printing imaging principle
To talk about digital printing inks, we must talk about digital printing machines, because the imaging principles of digital printing machines introduced by different manufacturers are different, and the requirements for the composition and performance of the digital printing inks used are also different. The imaging principles of digital ElSiJ devices currently in use can be divided into six categories.
1. Electronic photography
Also known as electrostatic imaging, it uses a laser scanning method to form an electrostatic latent image on a photoconductor and then uses the charge action of the charged toner and the electrostatic latent image to transfer the toner image to the substrate to complete printing.
2. Jet imaging
The ink is selectively ejected from the fine nozzles onto the substrate at a certain speed to achieve the reproduction of the ink image. Inkjet printing is divided into continuous inkjet printing and drop-on-demand inkjet printing. Continuous inkjet system uses pressure to make ink flow through fine holes to form continuous ink flow. At high speeds, the ink stream turns into tiny droplets and then charges the droplets. The charged ink droplets can be ejected to the desired position on the surface of the substrate under the control of the charge plate to form printed graphics. The offset of the ink droplet and the position of the ink dot on the substrate are determined by the amount of charge when the ink droplet leaves the pore.
The difference between on-demand inkjet and continuous inkjet is that the pressure on the ink cartridge is not continuous. Instead, it is controlled by the imaging digital signal, and it is ejected only when pressure is needed. On-demand inkjet can save the ink tank and circulation system because of no ink droplet offset, and the structure of the inkjet head is relatively simplified.
3. Electrocoagulation imaging
Electro-condensation imaging is caused by the electrochemical reaction between electrodes that causes ink to condense. And fixed on the surface of the imaging drum to form an image. The ink in the blank area where no electrochemical reaction occurs remains liquid and can be scraped off by the scraper, and the image formed by the fixed ink on the surface of the cylinder can be transferred to the substrate by pressure to complete the printing. The representative model of electro-coagulation digital printing machine is the product of EIcorsy. The resolution is 400dpi.
4. Magnetic recording imaging
Magnetic recording imaging is based on the formation of magnetic latent images by aligning magnetrons of magnetic materials under the action of an external magnetic field. Then the magnetic toner and the magnetic latent image are interacted under the magnetic field force to complete the development. Transfer the magnetic toner to the substrate to form an image. This method is generally only used for black and white printing.
5. Electrostatic imaging
Electrostatic imaging is the most widely used digital printing imaging technology. It uses the laser scanning method to form an electrostatic latent image on the photoconductor. The latent image is formed by the charge action between the charged toner and the electrostatic latent image, and transferred to the substrate to complete the printing. It is divided into two types according to the development method, which is electronic ink development. The resolution is 800dpi, represented by HPInd {go. The other is to use dry toner development, the resolution is 600dpi Xeikon, Xerox, Agfa, Canon Kodak, ManRoIand and IBM digital printers use this method.
6. Thermal Imaging
Thermal imaging is the imaging of the medium by the change of physical properties after the material is heated. Divided into direct thermal imaging and thermal transfer imaging. Direct thermal imaging is the use of specially processed substrates with special coatings, which change color after heating. Thermal transfer imaging ink is applied to the ribbon. The color film or ribbon is transferred to the printing material by heating, and the image quality can reach the photo level.
Digital printing ink
1. Dry powder digital printing ink
The dry powder digital printing ink is a dry powder ink formed by mixing a particulate charging agent with pigment particles to help charge formation and a fusible resin. The negatively charged toner is absorbed by the exposed part to form an image. The toner image transferred to the paper is heated and the resin in the toner melts, and is fixed on the substrate to form the image.
2. Liquid digital printing ink
Liquid digital printing ink is commonly used in inkjet printing, and the type of ink is related to the structure of the inkjet head. The inkjet head can be divided into two types: hot-press type and piezoelectric type, and the piezoelectric type has two types of high precision and low precision. EPS0N nozzles belong to high-precision nozzles Xaar and Spectra nozzles belong to low-precision nozzles. High-precision nozzles mostly use water-based dyes or pigment inks. The latter mostly uses solvent-based pigment inks.
Different from traditional inks. The curing of e-liquid ink on the medium does not depend on the drying time of the ink film. Instead, it encounters a high temperature (130 ° C) blanket immediately curing on the blanket. The ink graphics on the blanket are transferred to paper or other media 100%. on the other hand. The basic material of e-liquid ink is a new type of resin material, and its microscopic shape is polygonal. Under the action of pressure, unlike traditional inks, it is easy to diffuse, but it is solidified immediately after being in close contact with paper or other media to make the printed image clearer.
Electronic liquid ink is divided into water-based ink and oil-based (solvent-based) ink. Water-based ink consists of solvent, colorant, surfactant pH adjuster, drier and necessary additives. For hot-press inkjet printing system, only water-based ink can be used. Drop-on-demand inkjet inks are also usually water-based inks. Oil-based (solvent-based) ink is composed of colorant solvent, dispersed 3, J ~ n other regulators.
3. Solid digital printing ink
Solid-state digital printing inks are mainly used for inkjet printing. In the normal state, the ink is heated when the ink is heated, and the viscosity is reduced and then sprayed onto the surface of the substrate. Solid digital printing ink is composed of colorant, particle charge agent, viscosity control agent and carrier.
4. Electronic ink
Electronic ink is a special ink used for printing and coating on a special substrate material as a display. It is wrapped by microcapsules and its diameter is on the nanometer level. There are many positively charged white particles and negatively charged black particles in the microcapsules, and they are distributed in the transparent liquid in the microcapsules. When the microcapsules are positively charged. Positively charged particles gather on the side facing the observer. And it is displayed in white, when it is negatively charged. Negatively charged black particles gather on the observer's side. It is displayed in black. The position of the particles and the color of the display are controlled by the electric field, which is generated by the high-resolution display array backplane.
5. UV / EB ink
The so-called UV / EB ink is an ink that is cured by ultraviolet light or electron beam energy, and the application of uv / EB ink-type radiation-cured ink in inkjet printing is increasingly widespread. The biggest feature of UV inks in digital printing is good stability. The advantage of curing under uV light can effectively avoid clogging of the print head. Extend the actual life of the print head. But the shortcomings are. Printing with uv / EB ink will result in reduced printing speed. For example, the limitation of ink supply and the speed of a large amount of ink passing through the print head. At present, Xennla's new XenJetVivide series CMYK pigment uV curing ink has passed Xaar's certification. And use this new ink on Omnidot760 print head.
At present, the research of digital printing inks is in full swing in the world. Various digital printing machine manufacturers such as Canon, HewIettPackard, EPSONScitexXeikon, HPIndigo, etc. have researched and developed digital printing inks adapted to their system characteristics according to the characteristics of their digital printing machines. In addition, other well-known ink manufacturers in the world. Companies such as DIC, Sun Chemical, Flint Group, Sakata InxCorp and others have also begun to get involved in the development and production of digital printing inks. It is believed that with the widespread use of digital printing presses, the research and development of digital printing inks will be more in-depth. New digital printing 5a ink will continue to appear.