In the digital inkjet printing, high-speed ink jet is a decisive factor, determine whether the successful implementation of textile printing substrate. Therefore, the ink must be carefully prepared according to recipe, so that the ink used to meet the physical and chemical properties of the optimum process parameters to ensure effective operation and the printing surface of the fabric satisfactory prints.
For high-speed digital inkjet printing ink formulations requires a balanced performance, ensure stability before application of the best ink to make accessible high-speed jet operation. When the ink hit the fabric surface, the ink droplet should have the satisfaction of wetting / absorption characteristics. This pretreatment of the fabric of the pre-press control.
Clearly, the ink formulation must be applied to specific types of inkjet printing systems, whether based on piezoelectric demand drops (DOD) or thermal spray, or based on a continuous inkjet technology. For textile digital inkjet printing machine, about 80% of the use of piezoelectric demand drops, and the rest is mainly thermal spray. Therefore, the ink formulations of the ink must be matched with the printing machine to give a satisfactory performance of textiles (such as color, color fastness), the lowest cost efficient printing, and for the technical problems that may arise to provide the corresponding services.
Ink properties and requirements
High-speed digital inkjet printing ink preparation, and conventional dyeing and printing of traditional dyes or paints with different preparation, even with the same dyes, their preparation is not the same. Ink jet printing is a high-tech products, cutting-edge technology in textile printing played an important role. Currently, certain chemicals company for digital inkjet textile printing ink materials research and development work is very important. This is a creative field, high-tech chemicals used in textile expertise to provide workers for the printing ink formulations, to the technical requirements and printing ink to achieve the right balance between quality.
Digital Printing Dye
The traditional textile printing paste may contain 30% -50% of the dye, and the rest is thinner and dispersant; and ink used in digital inkjet printing must be high purity dyes and paints, and the ground state to the particles, fine degree of <1μm. Chromophore dye hair color performance to be very strong, because the typical business of printing ink in the dye concentration of only about 10%. In piezoelectric inkjet printing, a single channel in the maximum amount of ink applied only 20g / m or so, leaving the dye in the fabric for the 2g / m, with the traditional screen printing the dye uptake 100g / m, compared remain in the fabric dye, which is 5 times more than the former. In this way, inkjet printing is usually applied in a number of multi-channel ink printing pattern to enhance color depth. The higher intensity of dye color, the deeper the color the easier it is printed, but the ink-jet printing for textile color depth problems still exist.
Although some manufacturers use comes from the industrial digital printing machines print head, but most still use the original ink-jet printing machine designed for the printing industry, print head, because it may under the conditions of textile printing operations more reliable. Piezoelectric printhead can better balance the relationship between resolution and speed, and the development of new inks offer great scope. Use CMYK (cyan, magenta, yellow, black) color gamut of digital inkjet printing for textiles is not enough, you may use six-color, but usually greater use of eight colors.
At present, the acid dye can be used for inkjet printing, can be printed sportswear, swimwear, lingerie, fabrics and accessories for the flag; reactive dyes can be used in civilian clothes and underwear; and disperse the digital textile printing market, accounting for about 50%, large mostly as a transfer printing ink for printed clothing, bunting, automotive and furniture upholstery fabrics.