There are 2 ways to do this:-
1.Do it at database side
2.Do it at the application side
For the first one, you need to write an Inserted trigger so that when the record will be inserted to your table(when vendor send the email with list of material), your trigger should fire and send email.
For the second one, you need to write the .net code, that should run all the time and check for any new record and if so then send the email to the person.
Hope it will be helpful to you.
Pawan Awasthi(DNS MVM)
+91 8123489140 (whatsApp), +60 14365 1476(Malaysia)