I. Introduction
Revolution. Revolution.
2.he connotation of halogen
"Halogen" is Greek, which originally means saline alkali land. Halogen or halogen elements include five chemical elements, namely fluorine, chlorine, bromine, iodine and astatine. In the electronics sector, only bromine and chlorine are of the most interest.
3. What is the need for Hlogen-free?
The electronic wastes containing bromine and chloride compounds and plastic products contain halogen flame retardants and PVC. When these products are abandoned and burned, they are prone to produce dioxin and acid gas (HCl), which are harmful to the environment and human health through bioaccumulation. The United Nations international environment program has listed them as persistent organic pollutants.
Halides are widely found in printed circuit boards, welding masks, molding compounds, connectors, and other common electronic products. For example, the flame retardants of printed circuit boards contain halogen materials, and the toxicity of PBB and PBDE is the most concerned. Circuit boards and electronic products containing halogen will produce many by-products under incomplete combustion, including dioxins and furan like compounds, as well as acid or corrosive gases, which have potential hazards to the environment and human health. At present, most of the power and communication cables contain halogen, which will emit poisonous mist like chemicals when they are burning. In case of fire, the acid gas produced by cable burning will damage people's nose, mouth and throat, and the smoke will easily lead people to lose their direction, making it difficult to escape from the scene of fire. Therefore, EU ROHS regulations prohibit the use of PBB and PBDE in PCB. There are now attempts to limit the use of all halogenated materials in electronic devices. They believe that brominated materials can produce highly toxic dioxins when burning electronic devices. They asked for prohibited use of bittern materials beyond RoHS's original restrictions on PBB and PBDE.
Halogen free will probably become another green revolution in the electronics industry since the implementation of the directive on RoHS (hazardous substances restriction) in July 1, 2006. Halogen free will probably become another green revolution in the electronics industry since the implementation of the directive on RoHS (hazardous substances restriction) in July 1, 2006.
Lead can cause direct damage to the nervous system. Cadmium can cause injury to bones, kidneys and respiratory system. Mercury can cause damage to the central nervous system and kidney system. Six valent chromium can cause genetic defects; polybrominated two phenyl ether PBDE and polybrominated biphenyl are strong carcinogenic and teratogenic substances.
From lead-free, ROHS to halogen-free, to the POHS directive that Norway requires the prohibition of the use of 18 harmful substances, the increasingly strict environmental protection requirements for materials can not only significantly reduce the environmental pollution of electronic products, but also effectively protect our health.
Market drivers for halogen elimination:
(1) Environmental and health concerns
(2) some brominated flame retardants are indeed toxic (PBBs, PBDEs)
(3) many brominated flame retardants are similar to the known toxic PCBs
(4) it stimulates the Preventive Psychology of all brominated flame retardants
(5) toxic by-products produced by combustion treatment at the end of product life
(6) dioxin produced by incomplete combustion of halogen
(7) normal temperature combustion of waste electrical appliances prevails in the world
(8) environmental organizations strongly oppose brominated flame retardants
(9) driven by environmental organizations, OEMs are seeking halogen-free solutions and extending this requirement to the entire supply chain.
(10) major OEMs announce the elimination of bromide
Apple: eliminating PVC and brominated flame retardants by the end of 2008
Dell: eliminating brominated flame retardants in 2009
HP: eliminating PVC and brominated flame retardants in 2009
Carbohydrates containing chlorine form a small amount of dioxins and furans during combustion.
According to the fire data, the level of furan and dioxin produced by accidental fire has little effect on personal health.
4.Halgen-freergulations and contents
According to various industry standards, the acceptable halogen content is 900ppm for bromine, 900ppm for chlorine and 1500ppm for total halogen.
Specification for Hlogen free requirements:
IPC low halogen electronic standard working group 4-33A & JEDEC JC14 Committee: all PCB substrates must meet the requirements of low halogenated bromine and chlorine defined in the IPC-4101B standard. At present, RoHS II is being revised.
For many different sources of halogen, and the minimum impact of low level halogen content on the environment, most agencies use the content level specified by the international Electrochemical Commission (IEC) as the requirements of their final assembly products.
5、 Detection and analysis of non halogenation
In order to prove that the materials used for circuit board do not contain halogen, the manufacturer must carry out incineration test, and then determine whether there are halogen elements by ion chromatography. During combustion, the brominated activator materials decompose. In these materials, the atoms in the bromine are covalently bonded to synthesize the bromine molecules at room temperature
Test method:
1）prEN 14582 Characterication of waste – Halogen and sulfur content – Oxygen combustion in closed systems and determination method Mhod A （Calorimetric bomb method） Mthod B （Schoniger flask combustion method）
(2) IEC 61189-2 test methods for electronic materials, PCB boards, interconnection structures and assemblies Part 2 test 2C12 test method for interconnection structure
（3）JPCA-ES-01-2003 Test methods for halogen free materials
（4）IPC TM-650 （Number2.3.41）
6、 Challenges and opportunities of non halogenation process
For our Chinese enterprises, there are only challenges and no opportunities, because we are passive and forced to abide by the rules.
We must draw lessons from a series of environmental protection movements, such as lead-free and halogen-free, to arouse our vigilance. We managed to deal with lead-free, and soon there was halogen-free. If we deal with the past without halogenation, the next unexpected new movement will appear soon. Because the essence of the movement is "containment", and the means to achieve this goal are various. In order to meet the needs, we can find a grand reason at any time. The reason why Europe and the United States dare to do this is to see the weakness of the "R & D vacancy" prevalent in Chinese enterprises, and hit you, but you have no power to fight back, either be knocked down or forced to block.
