Development and Innovation of Nano Water-based Inks and Packaging Applications (I)

Abstract : This paper introduces the characteristics and characteristics of nano-water inks, proposes the improvement of nano-powder inks, analyzes the status quo of nano-packaging materials in China and innovative technologies in the development process of nano-water inks, and also applies nano-water inks in printing. The application prospects and market outlook are outlined.
Key words: nano-water ink, nano-encapsulated material, R&D process, innovative technology, application, prospect

0 Preface

Nanotechnology is an extremely rich term. Its basic meaning is to recognize and transform nature in the nano-scale space, and to create new substances by directly manipulating and arranging the laws and characteristics of the movement of atoms and molecules. This means that people can produce extremely pure materials, a variety of new products, and can greatly improve the efficiency of the machine. Nanotechnology refers to a comprehensive technical system for the preparation, research and application of substances at the nanoscale. The ultimate goal is to manipulate and control atoms and molecules to form artificial functional materials. The broad scope of nanotechnology may include nanomaterial technology, nanofabrication technology, nanometer measurement technology, nanometer application technology, and the like. The nanomaterial technology focuses on material production (ultrafine powder, coating, etc.) and performance testing 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 [1].

A famous scientist in our country pointed out: "In the "leadership" disciplines that represent the future development trend of science and technology in information science, bioengineering, and nanoscience, nanoscience is the smallest subject between China and developed countries, and it is also the most common in China. The disciplines that may keep pace with the developed countries." At the turn of the century, Xinhua News Agency reported on August 29th, 2000, a news review titled "A Nano-era of Decisive Battles - A Global Competition in the Field of High-tech Technology." This quickly enabled the nanometer to gain recognition from society.

Nanotechnology will become the leading technology for scientific development in the next two or three decades. The most important field of application of nanotechnology is the production of new functional materials with specific physical and chemical properties. The most typical application is to make two different kinds of materials into nanocomposite particles. The European Union issued a report as early as 1995: It is predicted that the development of nanotechnology will be second only to the chip manufacturing industry in the next 20 years, and will become the second largest manufacturing industry in the world. The future of nanotechnology far exceeds that of the computer industry. Based on historical experience and the latest scientific and technological development, many scientists in the world have determined that nanotechnology is a sign of the dawn of the industrial revolution and that its impact will be similar to that of microelectronics in the late 20th century.

The development of nano-science and technology is of great significance. First of all, it will change the traditional mode of production of mankind, increase social productivity unprecedentedly, and may fundamentally solve many serious problems that people face today such as environmental pollution, ecological balance destruction, raw materials and energy consumption, etc. At the same time, nanotechnology can Develop potential information and structural potential of materials, and increase the capacity of storing and processing information per unit volume of materials by more than one million times.

The technological innovation of this century is largely supported by clarifying more microscopic phenomena and developing operating techniques accordingly. However, this traditional technology development will encounter limits in many areas. If there is no new discovery that is fundamentally different from the traditional one, it will not be able to reach a new level. Nanotechnology is the unique structural technology that discovers this effect and artificiality. People fully grasp and utilize advanced modern science and technology to make prediction and research on nanotechnology possible.

As we all know, ordinary ink is a complex polymer composition, it has a specific viscosity and excellent printability. The main ingredients are pigments (dye), polymer binders, solvents, and small amounts of additives. When ink is formed, people put the above-mentioned components into a special apparatus according to a certain proportion, and are sufficiently dispersed to obtain a uniform printing ink having a certain viscosity and thixotropy.

Nano ink composition and manufacturing methods are no different from ordinary ink. If there is a difference, it is only the "pigment" particles used in the two inks, which vary greatly in particle size. The pigment size of conventional inks is in the micron (μm) grade, while the "pigment" size of the nanoinks is nanoscale. The difference between the two sizes is about 1000 times. The introduction of nano-specific “pigments” with specific energy will give moderate changes to the ink manufacturing process, which is understandable.

Although nano inks and common inks are used for printing products, the former mainly focuses on the application of special functions, while the latter is often used for printing monochrome or color prints.

Recently, although nano inks have just emerged, they have shown excellent performance in the fields of processing and installation of electronic components, decoration and decoration of high-end products, sterilization and detection of pharmaceuticals, and anti-counterfeit printing of special products. And great attraction [2].

1. Nano-aqueous ink characteristics and nano-powder ink improvement

In 1959, Richard Feynman, the physicist and Nobel laureate winner, first proposed the concept of nanotechnology, and nanotechnology was gradually paid attention to by people and widely used in 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. As the nano-metal particles can absorb all the light waves and make themselves appear black, they also scatter light. Therefore, with these characteristics, nano-metal particles can be added to black inks to make nano-inks to increase their purity and density. Due to the existence of significant quantum size and surface effects, semiconductor nanoparticles exhibit a certain degree of absorption of light.

With the continuous improvement of the printing quality requirements, the customer's requirements for printing products must not only be of good quality, but also be in line with various special needs such as environmental protection and anti-counterfeiting. Therefore, higher requirements are also put on the ink. The fineness and purity of the ink have a great influence on the quality of the printed matter. To print high-quality products, we must have fine, high-purity ink as a guarantee. The fineness of the ink is directly related to the properties of the pigments, fillers and the size of the particles. The fineness of the ink refers to the size of the pigments (including fillers) in the ink and the distribution of pigments and fillers in the binder. Uniformity, which reflects both the quality of the printed product and the printing rate of the printing plate.

Nanotechnology is emerging as a science and technology, and its main research object is nanomaterials. Today, nanomaterials have penetrated into various fields, and the printing industry is no exception. When nanotechnology is combined with printing inks, it can create inks with small particles (particles less than 100 nm) and high fineness. The finer the ink particles, the larger the contact area between the pigment particles and the binder, the better the printing performance, the more stable the printing performance, and the clearer and fuller the dot, which is called "nanometer ink."

Due to the saturated and bright colors of nano inks, the four-primary inks made with nano inks have a higher color gamut than traditional four-primary inks. In addition, nano inks still have the advantages of water resistance, abrasion resistance, and good penetration, which can not only retain the advantages of traditional inks, but also combine the advantages of nanotechnology [3, 10].

1.1 nanometer water-based ink characteristics and characteristics

1.1.1 nanometer aqueous ink composition [4,5]

Nanometer water-based ink is a uniform paste-like adhesive consisting of colored bodies, binders, extender pigments, additives, etc., capable of printing and drying on printed objects. The main agent of the nano aqueous ink consists of a pigment as a dispersed phase and a binder as a continuous phase. Pigments give the ink color, and the binder provides the necessary transfer properties of the ink. Nano-water ink composition shown in Figure 1.

1.1.1.1 Binder

The binder is a fluid part of the nano-ink, which enables the pigment, that is, the pigment, to be finely rolled and dispersed on the dispersing device; it is firmly adhered to the substrate, and the ink has the necessary gloss, drying performance, and print transfer properties. Nanoinks are generally named after their dissolution properties.

1.1.1.2 Pigments

Pigments are used in nano-inks to provide colors and various resistances (long-term) to inks, and also have a great influence on the rheological properties (fluidity, viscosity, etc.) of inks.

<1.1.1.3 Additives

Adjuvants (adjuvants) are some of the materials added to improve the performance of the ink itself in the manufacture of nano-inks and printing applications. According to the basic composition of the ink, in some features still can not meet the requirements of printing, or due to changes in conditions and can not meet the requirements of the use of printing, must add a small amount of auxiliary materials to solve. There are many types of additives for nano-inks, which are mainly the following: coupling agents, neutralizers, solvents (co-solvents), thickeners, anti-settling agents, anti-mold agents, wetting agents and dispersants, defoamers Agents and so on.
$Page break $

1.1.2 Nano-aqueous ink drying mechanism [6, 8, 11]

1.1.2.1 Drying of Water Dilution Type Binder

The principle of drying of the water-diluent binder is as follows: The water-diluent binder can dissolve in water because these polymer resins contain a COOH (carboxyl), an OH (hydroxyl), an NH2 (amino), a C One NH2 and one C, these groups are hydrophilic.

After a certain process, the polymer resin is made into an organic amine salt, which can be completely dissolved in water. Therefore, it is now possible to use a reaction between a carboxyl group and an amino group to form a viscous liquid that is soluble in water. Such as:

RC00H+NH2CH2CH2OH→RCONHCH2CH20H+H20

In water, the above product will form: RCO-N+HCH2CH20H, which has good hydrophilicity. Since the latent heat of evaporation of water is relatively large, the drying speed of the ink and ink will be slowed down, and at the same time, the decomposition reaction occurs due to instability of the amine salt in the heat, so the volatile drying is mainly used, and the reactive solidification and drying are performed. Once dried, the ink film becomes water. Reconstituted. The drying process is as follows:

1.1.2.2 Drying process of water-dispersed binders

The drying process of the water-dispersed emulsion binder can be described by a three-stage drying model: 1 The water evaporates from the surface of the wet film, the overall volume of the ink film decreases, and the dispersed polymer particles gradually concentrate; 2 The polymer particles start to contact each other ; 3 particles agglomerate to form a dry ink film. as shown in picture 2.

1.1.3 nanometer water-based ink characteristics and characteristics

After the surface of the nano-semiconductor particles is chemically modified, the surrounding medium of the particles can strongly influence the optical properties, and the red-shift or blue-shift of the absorption spectrum occurs. Experiments have shown that there is a clear blue shift in the light-absorbing edge of the Cds nanoparticles and a large red shift in the absorption edge of the TiO2 nanoparticles. If they are added to yellow and cyan inks to make nano inks, their purity can be increased. Printing of color prints using nano-inks with specific nano-particles will increase the level, and the ability to display details in images will also increase.

A huge change has been made in pigments for the ink manufacturing industry. It no longer depends on chemical pigments, but rather selects the appropriate volume of nanoparticles to present different colors. Because some substances are in the nanometer scale, different colors of different particle sizes, or different colors of different materials, such as TiO2, SiO2 in the nanoparticles are white, Cr2O3 is green, Fe2O3 is brown. According to this, the nano-metal particles can absorb all the light waves and make themselves black, and also scatter light. Adding nano-metal particles to the black ink improves the purity and density of the black ink (characteristics of the nano-pigment in Figure 3).

In practical verification of pigment nanocrystallization, the color appearance of nanometer pigments is far darker than that of submicron pigments. The main reason is that the particles of the pigments are large and the light will break through, and the light will scatter and emit light. Light penetrates through. The nanopigment has a small particle size, weak light scattering, a small spectral absorption area, and a light reflectance of less than 1%.