Soybean ink has gradually become the mainstream, and the global printing industry has entered the green era

【 Green environmental protection is one of the hottest topics in the printing industry in recent years. With the gradual improvement of people's environmental awareness, more and more people begin to pay attention to the adverse impact of printing on the environment and human health. Green printing is a kind of printing behavior that saves resources, protects the environment, protects the ecological balance, is conducive to the physical and mental health of practitioners, and meets people's safety consumption needs. In fact, since the 1980s, green printing has gradually become the mainstream of the development of the global printing industry, and China is now quickly integrated into the tide of green development of the printing industry.

According to the Announcement on the implementation of Green Printing jointly issued by the General Administration of Press and Publication and the Ministry of Environmental Protection in 2011, "green printing" refers to "printing methods with little impact on the ecological environment, less pollution, and saving resources and energy". The scope of implementation of green printing includes printing production equipment, raw and auxiliary materials, production processes, publications, packaging and decoration and other printed matter, involving the whole process of printing product production. It can be said that green printing begins with the selection of raw materials, goes through production, use, and ends in recycling, and must be "green" throughout the printing life cycle and coordinated with the environment.

Printing workshops in Europe around 1770

In terms of the specific concept and operational level, the requirements for green printing at home and abroad may be different, but they are consistent in terms of core connotations such as environmental friendliness, sustainability and health benefits. In the 1980s, green printing began to appear in the United States, Germany and other countries. Today, green printing is not only the embodiment of the level of scientific and technological development, but also an effective means to replace the traditional printing methods that produce environmental pollution and high energy consumption.

The industry believes that the main characteristics of green printing are reduction and moderation, non-toxic and harmless, pollution-free and pollution-free. Reduction and moderation refers to the moderate printing with the least amount and the most simplified process under the condition that green printing meets the functions of information identification, protection, convenience and sales; Non-toxic and harmless means that the printed material should not contain toxic substances, or the content of toxic substances is controlled below the relevant standards; Pollution-free and pollution-free means that in the entire life cycle of the printed product, it should not pollute the environment or cause public hazards.

The 11-color letterpress rotary soybean ink of a printing plant in Guangzhou, China stands out among the many raw materials used in the printing industry, and the environmentally friendly characteristics of the ink have long been strictly required and controlled by the industry. Generally speaking, green ink must have the following characteristics at the same time: ① low content of harmful substances such as heavy metals; (2) More renewable resources are used; ③ Good energy saving and emission reduction performance; ④ less migratory material. The first three properties are well understood, and the "migration" of the last property refers to the process by which harmful chemicals in the ink used to package food (such as paper products printed with promotional text to package fast food) are transferred to the food and cause contamination.

In the development and use of new ink, the technological progress made in the United States and Japan in recent years is more prominent.

American soybean ink logo

In the late 1970s, under the pressure of rising oil prices, the Newspaper Association of America decided to find new alternatives to the standard petroleum-based ink. After testing more than 2,000 different vegetable oil formulations, researchers at the Newspaper Association came up with a solution based on soybean oil. In 1987, researchers in the United States in the Iowa newspaper "Gazette" printing process, the soybean ink was tested and successful. Today, nearly one-third of newspaper presses in the United States use soy ink.

Soybean ink is not complicated to manufacture, and the main process is to refine soybean oil and mix it with pigments, resins and waxes. The printing industry has a special preference for soybean ink, not only because it is more clear and bright when printing color, but mainly because of its outstanding environmental characteristics: the degradation rate of pigment carrier in soybean ink is more than 4 times that of standard petroleum-based ink; Soybean ink is easier to remove than ordinary ink when deinking from paper, so soybean ink is more conducive to paper recycling. Other printers say they need less soy ink than regular ink to print the same amount of paper, thus reducing ink use and printer cleanup costs. The deficiency of soybean ink is mainly manifested in the drying speed, which is slower than that of conventional ink.