I am not familiar with the film in particular, but I know that most companies of ALL sorts demand by contract their name be inserted into the credits of a film if a product of their is used in context to the film itself... Check the end of the reel at the "Special Thanks To" section, if the knife wasn't just some nameless prop it will be in there.
Robert Joseph Ansbro
If it can be written, or thought, it can be filmed.
-Stanley Kubrick, 1928-1999