New concept ink characteristics and use (on)

With the continuous improvement of the printing quality requirements, higher requirements have been put forward for inks. With the rapid development of science and technology, various types of inks are constantly appearing in the fields of ordinary printing, special printing, and security printing. They not only require excellent quality of printed products, but also meet various special needs such as environmental protection and anti-counterfeiting. As a result, the emergence of such as magnetic ink, fluorescent ink, photo-induced changeable ink, temperature-varying ink, etc., has brought the development of the printing industry to a new height. Below, we briefly introduce the characteristics and uses of several high-tech specialty inks.

First, nano ink

We know that the fineness and color purity of inks have a great influence on the quality of prints. To print a high-quality product, we must have ink with good fineness and high color purity as guarantee. The fineness of ink refers to the size of pigments (including fillers) in the ink and the uniformity of the pigments and fillers distributed in the binder. It affects both the quality of printed products and the printing durability of printing plates. . Process practice shows that the printed or field version of the color printing product contains fine shades and shaded areas. In the printing process, stencils, stencils, and print quality problems easily occur. If operators do not carefully check and analyze, they may fall into the wrong operation, thinking that the consistency of the ink is not suitable, the viscosity is too high, the amount of ink is too large or the pressure is too high, and blind adjustments are made blindly. As everyone knows, this is caused by poor ink fineness. The fineness of the ink has a direct relationship with the pigment, the nature of the filler and the size of the particles. In general, inks made with inorganic pigments (excluding carbon black) have coarser particles. This has a lot to do with the rolling process of the ink. The more the ink is ground during the rolling process, the more uniform it becomes, the greater the contact surface between the pigment particles and the binder, the finer the ink particles, and the better and more stable the printing performance. In the case of printed anilox prints, the 1 to 40% dots in the high-profile and midtones on the layout are common. If the ratio of ink particles to the dot area is relatively close, then it is easy to make the dots empty or spread, and even the dots are not clean. Printing defects. Therefore, the higher the fineness of the ink, the clearer and fuller the dots on the print.

The fineness of the ink is low, the pigment is coarse, the friction coefficient during the printing process is large, the printing plate printing rate is low, and it is easy to produce the paste plate, the ink accumulation, and the uneven distribution of ink and ink during printing. The fineness of the ink can generally be judged by naked eye observation, that is, the surface scraped by the ink knife shows a smooth and uniform visual effect, indicating that the fineness of the ink is good; for example, a small scraped surface appears. A coarse or granular roughened layer has poor fineness of the ink. In addition, it is also possible to use a small amount of ink layer on the coated paper, and then use another layer of paper to grind the ink layer until the ink layer is dragged to a very thin, which means that the ink is fine. If traces of the ink layer appear, it is clear that the trace is caused by the coarseness of the ink pigments and filler particles. Of course, the above is judged only by experience, and the accuracy of discrimination has certain limitations. To achieve standardized, data-based judgment, only rely on fineness meter to determine the size of pigment particles in order to more accurately detect the fineness of the ink. The method is: dilute the sample ink to a certain degree, place it in the depth of the fineness meter, and then use the scraper to treat the groove movement (to maintain a constant speed) to the shallowest place, and the ink can be seen on the scale marks on both sides of the groove. The size of the particles can also be used microscopically to observe the size of the ink pigment particles.

Nanotechnology is an emerging technology. The nanometer is a length unit, which is 10-9m. The research object of this technology is mainly nanomaterials. Nanomaterials have now begun to penetrate various fields. In 1994, the XMX Corporation of Massachusetts, USA, has successfully obtained a patent for the production of nano-sized uniform fine particle materials for inks. Using nanoscale materials as ink pigments or fillers can greatly improve the fineness of the ink. Moreover, because nanomaterials have properties that are not found in some conventionally sized materials, some new inks are also available.

Nowadays, with the help of high technology, various components (such as resins, pigments, fillers, etc.) in ink can be made into nano-scale raw materials. In this way, due to its high degree of fineness and fine flow and lubricity, it can achieve better dispersion and suspension, stability, low pigment content, high hiding power, good gloss, fine resin particle size, continuous and uniform film formation, Thin film, print images more clearly. If used in UV inks, the curing speed can be accelerated, and shrinkage and wrinkling of the ink film can be eliminated due to the fine and uniform dispersion of the filler. In the glass-ceramic ink, if the inorganic material is made into nano-scale fineness, it will save a lot of raw materials and print more refined and more beautiful high-quality images.

Studies have shown that the optical properties of some nano-scale materials after the surface of the chemical modification, some of which appear as a red shift or blue shift of the absorption spectrum. Experiments have shown that there is a clear blue shift in the light absorption of CdS nanoparticles, and a large red shift occurs in the light absorption of TiO2 nanoparticles. Accordingly, if they are added to yellow and cyan inks to make nano inks, they can be Improve its color purity. The use of nano-inks with specific nano-particles to reproduce printed color prints will result in a richer hierarchy, a clearer tone, and a greater ability to express the details of the image. In addition, since some materials change their colors at the nanoscale, this creates a possibility for the ink manufacturing industry that inks may no longer rely on chemical pigments, but instead select the appropriate volume of nanoparticles to present different colors. .


Nano-scale carbon ink is conductive, has a good shielding effect on static electricity, to prevent the signal from external static electricity interference, if it is added to the ink can be made into conductive ink, such as large-capacity integrated circuits, modern contact panel switches, etc. . In addition, if Ag is made into nano-scale instead of micro-sized Ag in conductive ink, 50% of Ag powder can be saved. This conductive ink can be directly printed on ceramic and metal. The ink film is thin and uniform, smooth, and conductive. well. If the Cu, Ni material made of 0.1 ~ 1μm ultrafine particles, it can replace palladium and silver and other precious metals conductive.

In addition, some organic nanomaterials themselves have luminescent groups and may emit light by themselves. The printed matter printed with the ink added with this nano material does not need to be irradiated by an external light source, and can be recognized by the human eye by its own light emission. It can also achieve good results for anti-counterfeit printing and is used for outdoor large-scale advertising printing or printing. Photographic prints that are read at night eliminate the need for external light sources, which not only saves energy, but also greatly facilitates users.

Since nanomaterials generally have good surface wettability, in the process of manufacturing the ink, as long as a certain amount of nanomaterials are added, they are adsorbed on the surface of the pigment particles in the ink, which can greatly improve the wettability of the ink and can ensure the entire The ink dispersion is stable, so that the printability of the ink is greatly improved.

In the electrophotographic process, magnetic nanopowders are used instead of non-magnetic toners, which are widely used today, and ferromagnetic particles that are currently used as magnetic carriers can be dispensed with, and a developer for single-component copying can be produced, which can save raw materials and improve Copy quality.

With the further development of nanomaterial technology, it is believed that more nanomaterials with different characteristics will be recognized and used by people.

(to be continued)