What’s going on with Panasonic’s National and Panasonic brands?

National is the original trademark of Panasonic; Panasonic is the trademark that Panasonic integrated after annexing several small companies. National refers to Panasonic's sub-brand Panasonic Electric, which mainly focuses on industrial electrical products. Panasonic mainly focuses on electrical appliances and household appliances. It is also a sub-brand and is just two brands of Panasonic. Just like Toyota has Toyota and Lexus. Same