Study leave should concern training that adheres to a study plan. Thus, your application for leave must be accompanied by your notice of admission to the course so that the employer can decide if you are entitled to the leave. The training must lead to knowledge and contain teaching. Thus, self-study as such is not grounds for leave. However, there are no requirements of tests or exams.
Hobbies of leisure pursuits are not grounds for study leave, even though teaching may be involved. Conferences are not seen as being on study leave. You must have been employed by Uppsala University during the past six months or for a total of twelve months during the past two years at the beginning of the study leave. The leave must be requested two months before it should begin, and the employer has the right to postpone such leave for six months.
Law regarding an employee’s right to study leave (in Swedish)