[China Science Journal] You are my eye： Green printing opens a new chapter in Braille.

Photo courtesy of Institute of Chemistry, Chinese Academy of Sciences

　　Recently, researchers from the Green Printing Laboratory of Institute of Chemistry, Chinese Academy of Sciences walked into beijing school for the blind and donated books for the blind printed based on green printing technology. A second-grade blind child opened a brand-new book "Mindless and Unhappy" and boldly poked the salient points. "The teacher told us that we don’t have to worry about the bumps of the books that we have read." He told the reporter of China Science.

　　"Green printing technology has opened a new chapter in Braille." Jesuli Chen, vice president of beijing school for the blind, said at the donation site, "The new Braille books are durable, green and illustrated, which improves the effectiveness of teaching and learning quality and brings a’ visual’ feast to children."

　　Starting from the smallest point in the world

　　Braille books printed in the traditional way are mechanically imprinted, and after many times of touching and reading, many raised braille dots are smoothed out. At the same time, the long publishing period, high cost, low publishing volume, large volume and insufficient braille accuracy of Braille books directly restrict students’ learning. Li Xiaoxiao, a teacher in beijing school for the blind who has been engaged in Braille editing and engraving for a long time, is deeply touched by this. "Braille materials are heavy, thick kraft paper materials are also easy to scratch hands, and their service life and storage time are relatively short." She told the reporter of China Science.

　　Song Yanlin, director of the Green Printing Laboratory of the Institute of Chemistry, Chinese Academy of Sciences, who is engaged in the research and development of green printing technology, noticed this. Since 2014, researchers have successfully controlled the nano-scale interface properties between ink and substrate around the "coffee ring effect" in the field of inkjet printing, so that ink droplets no longer spread. On this basis, they printed the smallest ink dot containing only one nanoparticle at present, and then connected such ink dots into the thinnest lines to form a flat surface, thus overcoming the problem that nanoparticles form high-precision patterns by printing.

　　Song Yanlin realized that maybe green printing technology can realize durable, antibacterial and low-cost Braille printing. Therefore, with the support of the pilot project of Chinese Academy of Sciences, he led laboratory researchers to combine green printing technology with the principle of 3D printing and actively explore Braille printing.

　　On January 30th this year, Song Yanlin’s research team had an exchange with Guo Liqun, director of China Disabled Persons’ Federation, Li Qingzhong, vice chairman of China Blind Association, and Wo Shuping, deputy editor-in-chief of China Braille Publishing House. At this point, the green printing technology started from realizing the smallest point in the world, and went to the blind side step by step.

　　Full chain technology fills the gap

　　"It is not enough to have one technology. What exists in Braille printing is the problem of the whole chain." In the field of green printing technology transformation, Song Yanlin has accumulated some experience. He is well aware that in order for the blind to really use new blind documents, it is necessary to build a whole chain of system technology.

　　In terms of materials, the ink used by the researchers adopts environmentally friendly nano-antibacterial 3D materials. "This material permeates the surface of paper to form a film, which is deeply compounded with paper cellulose through capillary force. When cured, it forms an interpenetrating network structure between paper fibers and firmly combines with the surface of paper, making the formed braille bumps extremely resistant to friction and the braille books durable." Song Yanlin introduced.

　　On the printer, researchers used image segmentation to solve the contradiction between printing speed and accuracy, cut the large format into multiple small formats, and printed in parallel with multiple nozzles. This method not only improves the speed and accuracy at the same time, but also greatly reduces the cost. In addition, the researchers also developed a set of software to decompose the three-dimensional structure, which can realize the accurate printing of three-dimensional graphics through layered superposition printing. The first completed D74 printing device can provide a speed of about 400 pages per hour.

　　Li Xiaoxiao and the students couldn’t put it down when they got the brand-new Braille books: "The weight and comfort can reach the level of Chinese character textbooks. After repeated reading, the points are still clear, and the blind lines are smoother. "

　　Printing Braille into Life

　　Facing the future, Song Yanlin’s team will speed up the research and development of office-level and industrial-level Braille printing equipment. At present, the ink-jet printing method of green printing technology does not need plate making, is not limited by print volume, and can realize personalized customized service. Office environments such as schools for the blind, libraries and digital express printing centers will have a huge demand for green digital Braille printing.

　　According to the plan, office-level equipment will be equipped with two product sequences: desktop (low speed) and vertical (medium speed), which will share ink materials with other equipment, and the equipment volume will meet the needs of a relatively narrow space. The research and development of industrial equipment aims at greatly reducing the cost of paper. Researchers will jointly develop high-speed automatic green digital Braille printing production equipment with China Braille Publishing House to meet the demand of increasing production capacity.

　　In addition, in order to help the blind get a better life, at present, researchers plan to integrate green printed Braille into the universal design of consumer goods in daily life. "Braille printing and barrier-free signs are added to the packaging of medicines and foods. Through the application in the traditional packaging and labeling market, it is seamlessly connected with the existing technology, thus better serving the visually impaired groups. " Song Yanlin said.

　　Jesuli Chen expects to apply Braille printing to electronic products, and realize multi-sensory integration with audio, which will expand children’s imagination and change their lives.

　　(Originally published in the first edition of China Science Journal on May 24, 2018)