The properly and electrostatically measured taping materials are used for the components, but attention should be paid to the fact that there is some danger the parts absorb on the top
tapes to cause a failure in the mounting and the parts are destructed by static electricity (more than 1kV : 1J, 2A, 2B, 2E 0.5kV : 1E, Human Body Model 100pF 1.5kΩ) to change the
resistance in the conditions of an excessive dryness or after the parts are given vibration for a long time as they are packaged on the tapes. Similarly, care should be given not to apply the
excessive static electricity when mounting on the boards.
●
Ionic impurities such as flux etc. that are attached to these products or those mounted onto a PCB, negatively affect their moisture resistance, corrosion resistance, etc. The flux may
contain ionic substances like chlorine, acid, etc. while perspiration and saliva include ionic impurities like sodium (Na
＋
), chrorine (Cl
−
) etc. Therefore these kinds of ionic substances may
induce electrical corrosion when they invade into the products. Either thorough washing or using RMA solder and flux are necessary since lead free solder contains ionic substances.
Washing process is needed, before putting on moisture proof material in order to prevent electrical corrosion.
●
Please pay attention that the top of an iron does not direct touch to the components. There is a risk that may cause a change in resistance. Take care that another risk may happen that
the protecting coat is carbonized in an instant when touched directly by the top of the iron, also climatic-proof for electric corrosion or insulation of protecting coat may be dropped down.
Be sure not to give high temperature on the top of the iron as it will degrade the protecting coat.
●
Avoid storing components under direct sun rays, high temperature/humidity. Direct sun rays will cause quality change of taping and difficulty of keeping appropriate peeling strength. 5∼
35℃/35∼75%RH, there is no deterioration of solderability for 12 months, but take special care for storing, because condensation, dust, and toxic gas like hydrogen sulfide, sulfurous acid
gas, hydrogen chloride, etc. may drop solderability.
LG Display昨日发布的2018年第一季度财报再一次说明了面板行业寒冬正在到来。该财报指出，LG Display2018年第一季度营业亏损达980亿韩元，出现近6年来的首次运营亏损。此前发布的友达光电、京东方财报也说明，受液晶面板价格迅速下滑影响，友达光电、京东方的营收和利润也出现了同比下跌的现象。从去年第三季度以来，液晶面板价格持续下滑，因为去年6代线、8.5代线等新增产能的逐渐释放，液...[详细]
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