Where did Wilhelm Ostwald continue his research after retiring in 1906?

After retiring from the University of Leipzig in 1906, Wilhelm Ostwald continued his work as a freelance researcher at his private estate near Leipzig.21

At this estate, he had established a laboratory and a large library, which allowed him to pursue new scientific interests, most notably in the field of colour theory. In addition to his research, he remained highly active as a reformer in educational and organizational matters, contributing to international movements and scientific documentation standards.21