Most magnetic recording media are produced by coating a non-magnetic base such as a polyester film with a magnetic paint containing magnetic particles and a binder component that provides good adhesion between the magnetic particles and the base, and drying the web thereafter. Magnetic recording media are required to have good electrical characteristics as well as high durability and wear resistance. For this purpose, the binder component used must meet the following requirements: (1) it is capable of dispersing the magnetic particles uniformly, (2) it provides the magnetic recording medium with high electrical characteristics such as high sensitivity and high S/N ratio, and (3) it forms a highly wear-resistant and heat-resistant magnetic layer, thereby increasing the durability of the magnetic recording medium. Therefore, selecting a good binder component is very important for producing a magnetic recording medium with the desired characteristics. Conventionally, the binder is made of a material selected from among many thermoplastic and thermosetting resins, and in many cases, mixtures of polyurethane resins with vinyl chloride-vinyl acetate resins, cellulose derivatives, epoxy resins, or polyamide resins are used. But these resins are not completely miscible with each other, and they cannot form a completely uniform dispersion of magnetic particles, and they are not capable of producing a magnetic recording medium having the desired wear resistance and surface properties.
USPTO Backgrounds
USPTO Backgrounds