News from Japan: Development of Low-Dielectric-Constant Insulating Resins for 5G/6G Communication

Abstract

Dielectric materials play an important role not only in power and electrical equipment, but also in electronic and communication equipment. One type of communication equipment, now rarely used at least for long-distance applications but important until recently, is coaxial cable. Foamed and expanded polyethylene was used as the insulating material for this coaxial cable. Because the relative dielectric constant or permittivity of air is approximately 1.0, the lowest of all substances, the dielectric constant can be kept low by foaming the polymeric insulating material. As electromagnetism teaches us, electric energy or information, whether electricity or electromagnetic waves, is transmitted not through a conductor but through the conductor's insulation. The square root of the above relative dielectric constant is the refractive index, or the inverse ratio of the velocity of light or electromagnetic waves in a material to the velocity in a vacuum. Therefore, the application of insulating resins with a low dielectric constant to corresponding equipment is important to increase the speed of information transmission and communication. Toward the realization of a society with high-speed 5G/6G communications, insulating materials used in laminates and other materials are required to have a lower dielectric constant and dissipation factor to reduce transmission loss and increase transmission speed in the high-frequency band. For the these reasons, many resin manufacturers are actively working on developing insulating resins with a low dielectric constant for 5G/6G communications.