How to backup Attachments

I have a requirement where i need to delete few Account records from my Production and do backup for them in seperate sandbox.Backup of Accounts should also include all its related lists data including ATTACHMENTS.Am unable to export& backup attachments on those specific records that are to be deleted.

I did "Data Export" and also i exported through Data Loader using "Attachments" Object but i couldn't get any files except their Id's.

Can Someone help with your valuable suggestions?