When it comes to the profession of cultural relics restoration, many people are always full of curiosity. Cultural relics restoration is far away from people's daily life and full of mystery. Today coincides with international museum day. Zhang Zhangzheng, a cultural relics restorer of Tianjin Museum, and his apprentice lie in front of the restoration case to demonstrate to the audience how to repair calligraphy and painting cultural relics. "The restoration of cultural relics focuses on minimal intervention, and the restoration is also for protection." Zhang Zhang has been engaged in the restoration of cultural relics in Tianjin Museum for more than 30 years, and more than 300 calligraphy and painting cultural relics have been restored by him. As one of the intangible cultural heritages, the art of mounting and repairing ancient calligraphy and painting is mainly repaired by "Su mounting" in Beijing and Tianjin, and inherited in the way of "teacher inheritance system", with elegant form. Since most ancient calligraphy and paintings are painted on rice paper, cotton and silk fabrics, the restored ancient calligraphy and paintings are characterized by softness, softness, thinness and light. The restoration of ancient calligraphy and painting pays attention to the four steps of "washing, uncovering and completing". "Washing" is to wash the painting with clean water; "Uncovering" refers to uncovering the covering paper behind the painting; "Mending" is to repair and level the damaged place; "All" is to color the incomplete places with the same ink. The process of restoring ancient calligraphy and painting reflects the wisdom of our ancestors. The painting cases used for the restoration of ancient calligraphy and painting are very particular. "You see, if the painting is put on the red painting table, it is obvious that there are dirty places. It is much more convenient to clean the dust of calligraphy and painting." Zhang Zhang said that the red paintings in the cultural relics restoration room are made by the summer palace master with the traditional process of "dressing linen and hanging ash". This process can make the paintings more resistant to water erosion and not easy to crack. For the mold existing in calligraphy and painting cultural relics, Zhang Zhang advocated mainly washing with water, and try to avoid using chemical reagents such as oxalic acid for mold removal. According to the experience over the years, the integrity of ancient paintings can be guaranteed to the greatest extent by washing the paintings with water at different temperatures, supplemented by squeezing and discharging the stains out of the paintings with towels. At the same time, there are plans for the restoration of "replenishment" and "full" according to different cultural relics. Each plan has absorbed the experience of many repairmen. Each step needs more than ten days of preparation. Sometimes the masters of the Forbidden City are invited to participate in the discussion. Finally, only the tested plan can be implemented. For example, this year's amazing "a touch of green" is one of the difficulties in the restoration of cultural relics. Zhang Zhang said that when cleaning the dirt, you need to knead the flour into a dough to wipe off the dirt, brush the color with glue for three times, and then make complementary color, which is also the experience of several generations of cultural relics restoration division. Zhang Zhang said, "we will also use the combination of science and technology and traditional calligraphy and painting restoration techniques to better protect cultural relics. For example, when repairing" heavy color "ancient paintings, we will first use X-ray spectrum to analyze the color of ancient paintings, so as to provide more detailed diagnostic information and basis for preparing the plan." When talking about the significance of ancient calligraphy and painting restoration, Zhang Zhang said, "cultural relics are alive. We use restoration for protection, which is not only the cultural relics themselves, but also the cultural heritage represented by the cultural relics behind them." (outlook new era)