U.K. passport, married to a Swiss 28 yrs, which docs necessary for visa from Bern ? Thanks.

The invitation letter from your daughter is not mandotory, you just need to provide the below documents to apply for China tourist visa through China embassy in Bern:
1. your passport with at least 6 months remaining validity when you submit visa application
2. one recent passport photo
3. fill visa application forms V.2011A and V.2011B
4. the marriage license, your swiss husband's passport, the copy of marriage license and his swiss passport
5. copy of e-ticket.