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The PCB without halogen and halogen? And on the circuit board

Author:admin Addtime:2018-05-17 Click:15

The PCB without halogen and halogen? And the ink on the circuit board has no harm to the body?

The industry has been talking about Lead-free and Halogen free. Can anyone explain Halogen free PWB and Process?

Halogen free Chinese translated as "Halogen free", because the eu will begin in July 2006, strict requirements of PCB imported products do not contain Halogen material mixed among them, such as bromine (Halogen combustion is easy to produce dioxins and other toxic substances harmful to human body), base material for PCB, film (PP), green (Solder Mask) contains a small amount of Halogen elements, such as their use mainly in increases the degree of flammability of PCB, there are related to exclude Halogen replacement products on the market selling. Perhaps you will ask since Halogen removed, fire-resistant degree how to through the UL requirement? Actually burn prevention function can be used to other metal surface treatment such as immersion gold, tin, silver or the OSP, and so on process to replace the same. These efforts, most of them related to materials, making circuit board is not much need to process change problems. But in terms of PCB assembly, may need to consider the change will be a bit bigger.

The insulating paint is based on the polymer, and can be solidified into an insulating film or an important insulating material under certain conditions.

Insulating paint is generally composed of lacquer base, solvent or diluent and auxiliary materials. It is divided into four types: impregnating paint, covering paint, silicon steel sheet paint, anti-corona paint, etc.

Self-drying insulating paint is a kind of insulating paint that can be dried into film after coating. The mechanism of self-drying is divided into three types: Category is volatile drying, namely the high molecular weight solid resin dissolved in appropriate solvent, solvent volatilize after Shanghai juji, solid film forming resin. This type of insulating paint application is convenient, quick drying. But poor solvent resistance, thermal softening. The second is oxidation drying. This kind of insulating varnish contains dry vegetable oil, dry vegetable oil unsaturated double bonds in molecular structure under the action of oxygen in the air, oxidative cross-linking themselves, so as to achieve the purpose of drying. General oily, phenolic resin and drying oil alkyd resin varnish are oxidation drying insulating varnish. This type of insulating paint due to the content of vegetable oil is more, low heat resistant performance, to A level, E Level of insulating material, drying time is longer, often one day. The third kind is the normal temperature curing dry, this type of insulating varnish is at room temperature, chemical reaction and cross-linking curing. This kind of paint is a two-component or multi-component, active now. This kind of paint is commonly used as polyamide resin curing epoxy resin paint and two-component polyurethane coating, etc. This kind of paint as a chemical cross-linking, heat resistance, solvent resistance and chemical resistance are better.

If it is solvent, it may have some effect, but in addition to the production plant, it is generally said that there is no contact with these solvents. Therefore, it has no effect on the body.