The role of nanotechnology in the field of printing and packaging

Nanoscience and technology is a high-tech technology that was born in the late 1980s and rapidly rises. Its basic meaning is to understand and transform nature in the range of nanometers (ie 0.1 to 100 nm), through direct manipulation and arrangement of atoms and molecules. , Technical methods for creating new substances. This means that people can produce extremely pure materials and rich new products.

Application of Nanotechnology in Printing

1. Nano ink

Ink fineness is closely related to printing quality. The finer the ink, the stronger the coloring power, and the clearer and fuller the dots of the printed matter. Recently, the nano-grade transparent iron oxide pigments, which have been rated as national key new products by the Ministry of Science and Technology, have been successfully developed. Nano metal particles can absorb all light waves and make them black, while also scattering light. Adding nano metal particles to black ink can improve the purity and density of black ink. In addition, after the surface of the semiconductor nanoparticles is chemically modified, the medium around the Shanghai printed particles can strongly affect their optical characteristics, which show that the absorption spectrum is red-shifted or blue-shifted. If they are added to yellow and cyan inks to make nano inks, the purity of yellow ink and cyan ink can be increased, and the level of printed matter can be more abundant. Now, with the help of high technology, various components (such as resins, pigments, fillers, etc.) in the ink can be made into nano-scale raw materials. Because of their high fineness, they have good flow and lubricity. Effect. If it is used in UV ink, it can accelerate the curing speed and eliminate the shrinkage and wrinkling phenomenon of the ink film. Nano-scale carbon ink has conductivity and has a good shielding effect on static electricity. If ink is added, it can be made into conductive ink. In conductive ink, such as Ag made of nano-scale instead of micro-scale Ag, can save 50% of Ag powder, this ink can be printed directly on ceramics and metals, the ink film layer is thin and uniform smooth; if Cu, Ni The material is made of ultrafine particles of 0.1 ~ 1μm, which can replace precious metals such as palladium and silver to conduct electricity. The combination of nano and anti-counterfeiting technology will open up another vast world of anti-counterfeiting inks.

Some nano-powder particles can emit light by themselves, such as "-N≡N-" nano-particles, etc. After a few minutes of light, they can glow in the dark for more than 12 to 24 hours. The luminous intensity and maintenance time are 30% of traditional fluorescent materials. More than times, and the material itself is non-toxic, harmless, and does not contain any radioactive elements. Because nanoparticles have good surface wettability, they are adsorbed on the surface of ink pigment particles, which can greatly improve the ink's lipophilicity and wettability.

2. Nano ceramic anilox roller

The so-called nano-ceramics refer to ceramic materials with nano-scale phases in the microstructure, which greatly improves the strength, toughness and superplasticity of the materials. We know that the laser-engraved ceramic anilox roller is currently widely used in flexographic printing, and it is considered to be the key to improving the quality of flexographic printing. Narrow flexographic printing machines and UV ink flexo printing machines have almost all used ceramic anilox rollers. From the perspective of the development of flexo printing, ceramic anilox rollers will eventually eliminate all metal anilox rollers. The famous British material expert Cahn pointed out that nano-ceramics is a strategic way to solve the brittleness of ceramics. For anilox rolls used for flexographic printing, when the anilox roll is processed by plasma thermal spraying process, a high-quality ceramic coating is required to be sprayed on the surface of the substrate, the coating hardness range must be HV300 ~ 1300, general porosity It must be less than 1%. For anilox rollers higher than 1200 lines, the porosity must be less than 0.5%, and the coating structure must be uniform, high hardness, high density, etc., and the nano-specific properties of nano-ceramics improve ceramics. Hardness, toughness, and abrasion resistance lay the foundation for an anilox roller with excellent engraving. In short, as a high-tech with rapid research and development in recent years, its application in the field of printing will continue to develop in depth and breadth as in other fields.

3. Nano Paper

The fibers of trees, bamboo, and hemp used in traditional paper are thicker, and the particles of paint and filler are larger, which makes ordinary paper have the disadvantages of being resistant to water and moisture. Although offset printing paper and electrostatic copy paper are waterproof and moisture-proof, etc. Function, but writing is inconvenient. Nanotechnology is becoming more and more widely used in the paper industry. At present, Shanghai Printing Company can only process wood fibers to the level of micrometers (100-1000nm). Because the cell diameter of wood is relatively thick, the wood nano-technology can change the structure of wood cells and control cell growth, which may change the characteristics of wood. When the wood is processed to the nanometer level, the original cell structure of the wood will be destroyed, and the fibrous tissue structure will be changed. Cellulose, hemicellulose and lignin can be mechanically separated during the process, which can greatly improve the paddle production rate and Reduce the environmental pollution of the paddle and paper industry. In papermaking coatings, the application of nano-calcium carbonate in the coating of whiteboard can effectively improve the performance of whiteboard. The addition of nano-calcium carbonate is conducive to the improvement of several important performance indexes of the coating, such as IGT value, K & N ink absorption, smoothness, etc. At present, the use of nanotechnology in the paper industry has begun to enter practical production. For example: Henan Yinge Company and the Nanotechnology Research Institute of Central China Normal University use the most advanced nanotechnology in the world to prepare nanostructured layers on ordinary paper, and successfully developed Waterproof nano paper. In addition to maintaining the original writing and copying functions of paper, it also has the special properties of super-hydrophobicity and moisture resistance that ordinary paper does not have, improving the strength of the printed surface and reducing the rate of expansion and contraction.