According to the JPCA – ES – 01-2003 standard: chlorine (C1), bromine (Br) is less than 0.09% Wt (weight ratio) of the copper clad, defined as halogen-free copper clad. (at the same time, the CI + Br total less than 0.15%Â [1500 parts per million])Â Most of the halogen free materials are mainly composed of phosphorus and phosphorus nitrogen.when the phosphorus resin burning, it will thermal decomposition by heating and generate partial poly phosphoric acid,the partial poly phosphoric acid have strong dehydration property to come into being the carbon film on the surface of the high polymer resin,to insulated resin burning surface is exposed to air, that the fire is extinguished, flame retardant effect.
What’s the halogen-free copper clad materials
March 25th, 2016
What’s the meaning for S/M in PCB?
March 25th, 2016S/M means solder mask, it is a kind of the Liquid photosensitive ink, it is the green, yellow, red, black or white color on PCB surface. We print solder mask on the PCB surface that no need soldering, and then drying and curing.
With solder mask, the Tin won’t stick to the PCB.
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The advantage and disadvantage of aluminum PCB
March 18th, 2016The aluminum PCB is a unique metal base copper clad laminate , it has good thermal conductivity, electrical insulation properties and machining property.
The structure of aluminum PCB is divided into three layers.
First layer: base layer, it is the metal substrate, which can choose copper or aluminum.
Second layer: dielectric Layer, its thickness be from 0.003 inch to 0.006 inch.
Third layer: circuit layer, the copper thickness of the circuit is from 1oz to 10oz.
The advantage of aluminum PCB:
- it has good heat radiation and better strength.
The disadvantage of aluminum PCB:
- High cost.
- The current mainstream can only do single aluminum PCB, it is difficult to do double sided aluminum PCB.
- The product will be more easily to have matter in electrical strength and pressure.
Aluminum core PCB have good thermal conductivity but Ceramic PCB will better,if you would like to know more about the different from FR4,MCPCB and Ceramic PCB,pls visit to for more information.
