Mr.Baecker, you can get the visa on the same day of submitting visa application if you apply for the rush service.
The differences between tourist visa and business visa are:
Tourist Visa (L): issued to aliens who come to China for sightseeing, family visiting or other private affairs. Besides your passport, visa application form affixed with one recently taken photo, a Chinese hotel reservation certificate and a two-way air ticket is also required to provide. The Chinese embassy in Japan only issue L visa for the aliens holding Japanese Long-Stay visa (more than one year). So if you don't have the Japanese Long-Stay visa, you can't get a Tourist visa of China.
Business Visa (F): issued to aliens who are invited to come to China for a visit, investigations, giving lectures, doing business, carrying out scientific, technical and cultural exchanges, pursuing short-term advanced studies or doing short-term fieldwork, for a period of less than 6 months.
Besides your passport, visa application form affixed with one recently taken photo, an invitation letter from an authorized department of Chinese government is also required. If you don't have the Japanese Long-Stay visa, the chinese embassy in Japan still issue you a F visa.