Sechi Kato was Japan’s third woman Doctor of Science after Kono Yasui and Chika Kuroda, contributing to natural science, and in particular to chemical research through application of the absorption spectrum. 

　Kato was born in 1893 in Oshikiri Village (now Mikawa Town) in Higashitagawa District, Yamagata Prefecture. Her family were major landowners in Oshikiri, but their large-scale dairy operation failed in her father’s generation, and then in 1894, Kato’s mother, brother, and sister were buried under the family home by the Shonai Earthquake and perished in the flames. Her father remarried and tried unsuccessfully to restore the family’s fortunes. He succumbed to illness in 1908.  

　Kato was studying at Tsuruoka Women’s High School (now Yamagata Prefectural Chidokan Junior and Senior High School) but decided to become a teacher to financially support her family, so she left and reenrolled at Yamagata Women’s Higher Normal School (now the Yamagata University Faculty of Education, Art and Science). She graduated top of her class in March 1911 and began working at Karikawa Elementary School. In 1914, however, she went to Tokyo at her stepmother’s urging to enter the Division of Science at Tokyo Women’s Higher Normal School. After graduating with excellent grades in 1918, she was employed at Hokusei Girls’ High School (now Hokusei Gakuen Girls’ Junior and Senior High School) in Sapporo, Hokkaido. In summer that year, she took a group of students from Tokyo Women’s Normal School to visit Hokkaido Imperial University. Hearing from the university president that while there were currently no women students, the university was not closed to women, she immediately applied for admission. Against the president’s will, however, many faculty members opposed her admission, so she had to go as far as engaging in a sit-in in front of the president’s office. In the end, while she was not recognized as a regular degree student, she succeeded in enrolling as a non-degree student eligible to attend all the same lectures and receive the same training and teacher guidance as regular students. She was Hokkaido University’s first woman student. Kato completed all 25 of her courses in three years and wrote a well-received graduation thesis entitled “The effect of dry conditions on the germination of apple seeds.” She became an assistant in the Department of Agricultural Chemistry at Hokkaido University’s School of Agriculture, leaving her position at Hokusei Girls’ High.

　A year later in 1922, Kato became the first woman research student at the Institute of Physical and Chemical Research (RIKEN) in Komagome, Tokyo. In the meantime, she had married the architect Sato Tokusaburo from her hometown. She gave birth to a son in the same month that she joined RIKEN, and to a daughter two years later. 

　At RIKEN, she studied spectroscopy, using the absorption spectrum to analyze chemical compounds, and in 1931, she submitted her doctoral dissertation, “Polymerization of acetylene,” to Kyoto Imperial University along with 12 sub-theses, receiving the degree of Doctor of Science.

　Continuing with her work, she became a RIKEN research scientist in 1942 and, in 1953, RIKEN's first woman chief scientist. After statutory retirement in 1955, she remained at RIKEN on a contract basis to continue her research until fully retiring in 1960. She subsequently taught at tertiary education institutions like Sagami Women’s University, Kawamura Junior College, and Ueno Gakuen University, as well as running science seminars for junior and senior high school science teachers on a voluntary basis, providing guidance for the next generation. 

History