IEC EN 61249-2-21 Materials for Printed Sheets and Other Interconnected Structures - Part 2-21: Reinforced Base Materials, Coated and Uncoated - Halogen-Free Epoxide Woven E-Glass Reinforced Laminate Sheets of Defined Flammability (Vertical Burning Test), Copper Clad

The standard "IEC EN 61249-2-21 Materials for printed boards and other interconnected structures - Part 2-21: Reinforced base materials, coated and uncoated - Halogen-free epoxide woven E-glass reinforced laminated sheets of defined flammability (vertical burn test), copper clad", which has its basis in a European standard and was subsequently published by the International Electrotechnical Commission (IEC), specifies the requirements for the properties of halogen-free epoxide woven E-glass reinforced laminated sheets of defined flammability in thicknesses from 0,05 mm to 3,2 mm.

The degree of flammability is achieved through the use of halogen-free inorganic or organic compounds that act as fire retardants. These fire retardants are present as part of or in addition to the polymeric structure. The glass transition temperature is defined as a minimum of 120 degrees. Some property requirements may have several performance classes. The desired class must be specified on the purchase order, otherwise the default material class may be supplied.

Halogens are highly reactive and can be harmful as they have the ability to form toxic and corrosive gases. Therefore, there is a need to use halogen-free adhesives in many applications in various industries such as electronics, aerospace and optics. Due to the concern about health and environmental problems caused by halogens, halogen-free has been defined by the International Commission on Electrochemistry (IEC) as:

• Chlorine maximum 900 ppm
• Bromine max 900 ppm
• Total halogens not more than 1500 ppm

Halogens, which include fluorine, chlorine, bromine, iodine and astatine, are essential elements for various industrial applications, especially in the field of electrical and electronic products.

Halogens are ubiquitous in everyday life and originate from natural reservoirs such as the sea, volcanoes, and fumaroles. Their essential functions extend to products as diverse as swimming pool disinfectants, drinking water treatment solutions, toothpaste formulas, and table salt. Although trace amounts of halogens are essential for health, their widespread use is drawing increased scrutiny due to emerging environmental and safety concerns.

Uses of halogens in the electronics world include:

• Indispensable components: Halogens play an indispensable role in various components in the electronics industry, from printed circuit boards to electrical cables.
• Flame retardant properties: Flame retardants, especially halogen-based, are used to increase resistance to heat. This property is crucial in preventing combustion during fire incidents and improving general safety measures.
• Example application in plastics: Polyvinyl chloride (PVC), a common plastic in electronics, is a prime example of the flame retardant properties attributed to halogens. Its widespread use highlights the effectiveness of halogen-based compounds in ensuring the safety and reliability of electronic devices.

Various countries have implemented regulations to restrict the use of hazardous halogenated compounds. Meanwhile, the International Electrotechnical Commission (IEC) is crucial in setting industry benchmarks. Standards such as IEC 62474 promote transparency by addressing hazardous substance reporting. Additionally, specific standards for fire safety focus on limiting halogen content in critical applications such as electrical wiring. These standards aim to improve safety measures during fire incidents and minimize environmental impact.

Additionally, legislation has been enacted in European Union countries that limits halogenated flame retardants in certain plastics. Manufacturers comply with the regulations by developing products with reduced halogen content.

In conclusion, despite the versatile applications and undeniable benefits of halogens, they require a smart approach to address possible risks. Standards development plays an important role in clarifying terminology, ensuring environmental safety and encouraging innovative steps in halogen-free material development.

Standardized practices not only increase industry transparency, they also contribute to a sustainable future.

Our organization has a strong staff that closely follows the developments in the world in the field of science and technology and constantly improves itself. Among the numerous test, measurement, analysis and evaluation studies provided for businesses in various sectors, there are also test services in accordance with the standard “IEC EN 61249-2-21 Materials for printed boards and other interconnected structures - Part 2-21: Reinforced base materials, coated and uncoated - Halogen-free epoxy woven E-glass reinforced laminated boards of defined flammability (vertical burn test), copper clad”.