Pipe/waste leak under kitchen sink - how to fix?

WIAWSNB

Could you clean up the logo, and take a crisp photo of it, please? See what make it is. 

Anyone know?

DIYhelp76

Thanks again everyone for the helpful replies.  WIAWSNB, thanks for the suggestion.  I was able to turn the screw in the waste a little bit.  I've dried and cleaned the outside and will place plastic pot under and see if there are any ongoing leaks.  With luck the tightening will do the job and I can take the easy/lazy option of not dismantling and replacing the washer.  But if I do need to, I know how to do this thanks to the posts above. :-)