This is a vintage Kanto style gyuto, produced around the 90's. These knives are very thin, the steel feels and sharpens like most SK steel.  This knife also has a slightly convex right side and a fairly flat left side , creating food release for a right handed user.

The Gyuto is the Japanese version of french Chefs knife.

Carbon steel knives are known for their sharpness, edge retention, and durability. They hold a sharp edge for a long time and are easy to sharpen and maintain. However, they require proper care to prevent rust and will “patina” after cutting highly acidic or alkaline foods.

This knife is made from carbon steel and will form rust if it is left wet after use.