On the harm of electromagnetic radiation and effective protective measures

1. The basic concept of electromagnetic radiation

1. Common sources of electromagnetic radiation

Generally speaking, radar systems, television and radio transmission systems, radio frequency induction and medium heating equipment, radio frequency and microwave medical equipment, various electrical processing equipment, communication transmission stations, satellite earth communication stations, large power generation stations, power transmission and transformation Equipment, high-voltage and ultra-high-voltage transmission lines, subway trains and electric trains, and most household appliances are all sources of electromagnetic radiation that can produce various forms, different frequencies, and different strengths.

2. Division of electromagnetic radiation field

The electromagnetic radiation field is generally divided into far field and near field.

With the field source as the center, the area within a wavelength range is usually called the near-field field, which can also be called the induction field; the spatial range outside the radius of one wavelength is called the far-field field, also known as the radiation field.

Generally, for a fixed electromagnetic radiation source that can produce a certain intensity, the intensity of the electromagnetic field radiated by the near field is relatively large, so we should pay special attention to the protection of the electromagnetic field in the near field. In addition, there is a concept to deal with the near-field field. The frequency range we are most often exposed to is 30MHz from shortwave to 3000MHz from microwave, and its wavelength range is from 10 meters to 0.1 meters.

Second, the harm of electromagnetic radiation

With the rapid development of the electronics, electrical, communication and information industries, electronic instruments and electronic equipment composed of integrated circuits (ICs) and large-scale integrated circuits as cores are widely used in various fields of modern society. It has brought a series of new problems to people, mainly manifested in the harm caused by electromagnetic wave radiation: such as electromagnetic wave interference, electromagnetic wave information leakage and the harm of electromagnetic environment pollution, etc., it has become a more and more serious and more and more people Issues of concern.

Copper series (PLS-100, PLS-200)

In order to make the coating film have a long-term stable shielding effect to electromagnetic waves within 3 GHz, Bolusi has carried out a reasonable technical design centered on copper fillers. After coating the inside of the plastic box of electronic equipment such as medical electronic equipment, communication equipment, office automation equipment, etc., it can prevent the leakage and intrusion of unnecessary electromagnetic waves, and can also be used in factories and buildings to prevent electromagnetic wave interference . The film thickness is only 30 microns, but it has good conductivity. The high-performance polymer with its special structure fully solves the oxidation problem of the copper filler, thereby ensuring the shielding performance for more than 10 years. According to the test results of the authoritative department, the shielding effectiveness of this series is as high as 53-77dB.

PLS-100 is a coating for the purpose of shielding near-field electromagnetic waves. Main uses: electronic equipment and auxiliary equipment. PLS-200 is a coating for the purpose of shielding far-field plane waves. The main purpose: high-frequency shielding and interference prevention.

Magnetic series (PLS-A20, PLS-A50)

When the operating frequency of electronic equipment is in the high-frequency range, the shielding of the reflection of GHz high-frequency electromagnetic waves often brings about the problem of secondary interference. Therefore, absorption-type shielding materials are indispensable. Borus magnetic series combines graphite and manganese-zinc soft ferrite organically, and carries out rigorous technical design to shield and absorb magnetic field waves and high-frequency electromagnetic waves. Not only can it absorb low-frequency electromagnetic waves from about 50Hz to 500KHz, but also can absorb high-frequency electromagnetic waves from 2GHz to more than 40GHz, and the absorption performance exceeds 15 dB.

PLS-A20 and PLS-A50 are coatings for the purpose of preventing the ghosting of televisions, radars and monitors to prevent electromagnetic wave reflection. In addition, PLS-A50 contains conductive fibers and can function as a dipole antenna.

Borus enters the Chinese market in only half a year, but has successfully solved the electromagnetic radiation problems of DVD, medical electronic equipment and other products for many manufacturers, so that it meets the electromagnetic compatibility standards, and removes the obstacles for successfully passing 3C certification.

The advent of the electronic age has made competition in the field of electromagnetic radiation protection materials fierce. As a branch of materials science, electromagnetic wave shielding coatings, its wide application and close correlation with its electronic information industry will make it a rising emerging industry. Materials are the foundation of technological progress, new material technology is the foundation of modern technological revolution, and an important milestone of human progress. For example, the development and utilization of steel materials drove the first industrial revolution, and the invention of silicon semiconductor materials promoted electronics, computers, and information The industrial development of technology, the birth of shielding coatings, especially absorbing coatings (PLS-A20, PLS-A50) will inevitably drive the next industrial revolution.