Green ink and future development of green printing (2)

(3) Water-based UV ink

Water-based UV inks are currently the new direction of UV ink research. Prepolymers in general UV inks are generally very viscous and need to be diluted with a reactive diluent. The currently used thinner acrylate compounds have different degrees of skin irritation and toxicity. Therefore, while developing low-viscosity prepolymers and low-toxic reactive diluents, another development direction is to study water-based UV inks, that is, water. Ethanol and other diluents. At present, water-based UV inks have been successfully developed and have been used in some printing applications. In addition, alcohol-soluble inks, which mainly play a role in flexo printing, are also very small-pollution inks. They are mainly used in food, medicines, beverages, tobacco, and daily-use packaging and printing that are in contact with the human body.

(4) Bio Ink

American scientists have long been working on a protein molecule called bacteriorhodopsin. Natural materials can often exhibit complications that cannot be easily obtained from fabricated materials such as semiconductors. Bacteriorhodopsin originates from an intense purple cell membrane that is grown in the body of a salt marsh known as the "halophilic halophilic salt." Illuminating its protein can trigger a photochemical reaction circle. The principle is that the photochemical reaction circle transports protons along the channels surrounding the cell membrane. The purple color of this cell membrane originates from the bacteriorhodopsin component known as the "retina." Acetamic acid in the cell membrane channel strongly binds to the "retina." The dissolved "retina" does not bind with amino acid and is pale yellow. Two sets of lasers of different wavelengths are alternately irradiated onto the protein molecules, and the protein molecules can be switched back and forth between the purple structure and the yellow structure. It is this habit that motivates people to study and use it. It can be used as a photosensitive element in an analog retina, as a memory element in a germanium-based processing device or as a memory element in an optical computer, and its thin film can also change color in accordance with the conversion of an external electric field. In conventional bacteriorhodopsin, under the influence of different electric fields, a low contrast color change from purple to blue is formed. However, the bacteriorhodopsin structure produced by certain mutants changes from blue to light yellow under the action of a strong electric field. By sandwiching the protein film in a transparent plate combined with a large number of electrodes, a display plate can be made. Applying appropriate voltages to different parts of the film can "write" a page of text or "place" an image. Just like ink, images on the bacteriorhodopsin display can also be seen under normal light. Moreover, the color transition time can be accelerated to 200μm. At present, the main difficulty faced by the entire development work is the need to consume hundreds of volts of electric field to stimulate its color transformation. Researchers are working hard to conduct research in this area and expect breakthroughs.

(5) New environmentally friendly ink

Osaka-based Printing Ink Co., Ltd. has recently introduced a new eco-friendly ink that is a sheet-fed offset printing ink that complies with the green mark certification standards revised by the Japan Environment Association at the end of last year. It has the following features: (1) Conforms to the newly revised green mark, "Lithographic ink V- 2) Standards; (2) Won the American Soybean Association accreditation; (3) Compliance with the Japan Printing Industry Association's environmental standards; (4) GPN's ordering guidelines; (5) 100% vegetable oil inks based on soybean oil; (6) VOC content is less than 1%; (7) Good stability and transferability on the machine; (8) Good abrasion resistance, gloss, and hair color; (9) Excellent fountain solution adaptability; (10) Easy to use Biodegradation and deinking; (11) Excellent compatibility with UV-OP varnish and better gloss; (12) Excellent printability for double-sided 8-color machines.

Source: hc360 HC Security Industry Channel