Application of Nanotechnology in Ink

Nanotechnology (1nm nm = one billionth of a meter) is a hi-tech technology that was born in the late 1980s and has rapidly emerged. Its basic meaning is to recognize and transform nature in the nanometer size (0.1-100 nm) range. Through the direct manipulation and arrangement of the laws and characteristics of atomic and molecular movements, technologies and methods for the creation of new materials. This means that very pure materials and a variety of new products can be produced. Today, nanotechnology includes nanophysics, nanochemistry, nanomaterials, nanobiology, nanofabrication, and nanomechanics.

First, the characteristics of nanotechnology

"Nano Meter" is a unit of measurement. About 1 atom is about 45 atoms long. After the invention of scanning tunneling microscopy in 1981, a world of molecules ranging from 0.1 to 100 nanometers in length was created. The goal was to reconstruct products with specific functions directly from atoms or molecules. Therefore, nanotechnology is actually a technology that uses a single atom and a molecule to project a substance.

Nanostructured materials are abbreviated as nanomaterials, which means that their grain size is between 0.1-100 nanometers. Studies have shown that when small particles enter the order of nanometers, they themselves have a quantum size effect, a small size effect, a surface effect, and a macroscopic quantum tunneling effect. Nanoparticles have a large specific surface area, surface atomic number, and surface energy, and the surface tension increases rapidly with the decrease in particle size, resulting in different thermal, magnetic and photosensitivity characteristics and surface stability of the nanoparticles from normal particles.

Since the size of nanometer-sized particles is close to the wavelength of light, coupled with its special effect of having a large surface, the characteristics it exhibits, such as melting point, magnetic, optical, thermal, and electrical conductivity, are often different from the material in its entirety. The nature of the performance of the state. Nanomaterials have a certain degree of uniqueness. When the material scale is small to a certain extent, the behavior of quantum mechanics must be used instead of traditional mechanics to describe its behavior. When the size of powder particles is reduced from 10 microns to 10 nm, the particle size Although it is changed to 1000 times, it will be 109 times larger when it is converted into volume, so there will be a significant difference in the behavior of the two.

The reason that nanoparticles are different from bulk materials is that their surface area is relatively increased. That is, the surface of ultrafine particles is covered with a staircase structure. This structure represents unstable atoms with high surface energy. Such atoms can easily bind to foreign atoms and provide large surface active atoms due to the reduced particle size. The particle size of the nanoparticles is less than the length of the light wave and therefore will have a complex interaction with the incident light. Under the proper conditions of vapor deposition, the metal can be easily absorbed light ferrous metal particles, called metal black, which is in contrast with the high reflectivity shiny surface of the metal in the vacuum coating. Nanomaterials can be applied to infrared sensor materials due to their high light absorption characteristics. The broad scope of nanotechnology may include nanomaterial technology, nano-processing technology, and the like. The nanomaterial technology focuses on material production (ultrafine powder, coating, etc.) and performance detection technology (chemical composition, microstructure, surface morphology, material, chemical, electrical, magnetic, thermal and optical properties). Nano-machining technology includes precision machining technology (energy beam processing, etc.) and scanning probe technology.

Second, the application of nanotechnology in ink

(1) From the ink fineness and purity

The fineness of the ink and the quality of the purity are very sensitive to the influence of the print quality. To print high-quality products, we must have fine, high-purity ink as a guarantee. Therefore, improving the ink purity and fineness is also an important part of the research of new inks. This is basically the case in security printing or ordinary printing, and in offset printing, flexo printing, and gravure printing. The fineness of the ink refers to the size of the pigment (including filler) particles in the ink and the uniformity of the pigment and the filler distributed in the binder. Therefore, how the fineness of the ink reflects both the quality of the printed product and the printing rate of the printing plate. According to the actual operation situation, the dot printing or field layout of the color printing product contains fine anti-white characters and lines, and the quality of the seizing plate is likely to be faulty during the printing process. If it is not carefully checked and analyzed, it may be misunderstood and the ink consistency may be felt. Discomfort, too much viscosity, too much ink, or too much pressure to make blind adjustments. As everyone knows, the real reason is that the fineness of the ink is not good, that is, the ink particles are too coarse. 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 (not including carbon black) have poor fineness and relatively coarse particles, which is closely related to the rolling operation of the ink. The more the ink is ground in the rolling process, the more uniform it is, the larger the contact area between the pigment particles and the binder, the finer the ink particles, and the better and more stable the printing performance. Obviously, the fineness of the ink is closely related to the printing quality. For instance, dot printing is used as an example. There are many 1-4% dots in the high-profile and intermediate tone on the layout. If the ratio of ink particles to the dot area is relatively close, then , it is easy to make outlets empty or fluffy, and even the printing of shortcomings is not solid, so the higher the fineness of the ink, the more clear and full of dots on the printed matter. In addition, the finer the ink, the greater its concentration, the stronger the color rendering power, and the higher the product print quality. The fineness of the ink is not good, the pigment is coarse, the friction coefficient during the printing process is large, and the printing plate printing rate is low. In addition, coarse-grained inks are also prone to paste and ink deposits during printing, as well as uneven distribution of ink and ink. The fineness of the ink can generally be judged by naked eye observation, that is, the surface scraped by the ink knife, if it is smooth. A uniform visual effect indicates that the ink is fine. If the scraped surface shows a lumpy or granular rough layer, the fineness of the ink on the surface is poor. 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, it is still very smooth, indicating that the fineness of the ink is good. If traces of the ink layer appear, it is obvious that the pigments and fillers in the ink are caused by coarse particles, indicating that the fineness of the ink is not good enough. Of course, the above is only judged by experience, and the accuracy of the judgment 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 specific method of measuring the fineness of the ink with a fineness meter is to dilute the sample ink to a certain degree, place it in the deepest part of the fineness meter, and then use a spatula to move along the groove (to maintain a constant speed) to the shallowest point. The ink particle size can be seen at the scale marks on both sides of the groove. In addition, the size of the ink pigment particles can also be observed using a microscope.

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