The printed circuit board is not vacuum packaging until becoming OK board,means that it is passed in the final quality control,and then would be shipped for you.
Why does package with vacuum?
How to protect after the vacuum package ?
How long can be saved ?
The protection and valid date of PCB from circuit board factory is show to you as follow:
Why does package with vacuum? Different with a small problem,it is very important for many manufacturers. If without good tightness,the part of PCB like immersion gold,hot air leveling and PAD would be oxidized,which is bad for production.
How to protect the PCB?
As a special item,it cannot touch with water and air. So at the first,the vacuum layer must be completed good,and it is necessary to place a bubble around the packaging box before package,because the bubble water absorption work well on moisture. What’s more, moisture proof beads is also necessary.Secondly,classify and put in order and label. The box must be kept in the dry and ventilated place after sealing,and prevented from the sun,and the best temperature of warehouse should be control under 23±3℃，55±10%RH. Meet above conditions ,the PCB whose surface treatment is with immersion gold ,gold plating,hot air leveling ,silver plating and ect can be general saved 6 months,and the surface treatment is immersion silver,immersion tin and OSP can be saved 3 months.
As for a long time idle PCB,the best protection is brushed three paints that can be moisture-proof,dustproof and oxidation-proof,and then can be saved 9 months.
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