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HDI工艺中取代涂树脂铜箔适合激光钻孔的半固化片 总被引:1,自引:1,他引:0
应用于HDI的激光钻孔半固化片的方法和其它常规材料相比具有的优缺点。 相似文献
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在过去几年里,小型PCB诸如硅芯片级以及便携式移动电话的生产者和设计者们已经发现:如果要保持自己的竞争力并具备生产高密度封装板能力,就必须采用微孔技术。微孔技术的出现要求针对微孔缺陷的有效检测手段对工艺进行过程控制。本文对激光微孔的自动光学检测进行了详细介绍。 相似文献
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M. Boutin J. Lesage C. Ostiguy M. J. Bertrand 《Journal of Analytical and Applied Pyrolysis》2003,70(2):505-517
Polyurethanes are widely used in the manufacture of commercial products such as foams and paints. During combustion, these polymers can generate isocyanates, which induce adverse health effects. Polymer pyrolysis (Py) hyphenated with mass spectrometry (MS) allows the investigation of polymer thermal degradation over time/temperature. A diphenylmethanediisocyanate (MDI) polyurethane foam was analyzed with electron ionization (EI) and metastable atom bombardment (MAB) ionization at a pyrolysis temperature of 400 °C. The recently introduced MAB ionization source uses discrete energy stored in metastable atoms of gases to ionize the analytes. This characteristic allows modulation of the ionization energy by simply changing the ionization gas. The extensive fragmentation of molecular ions observed using EI 70 eV is not totally eliminated with EI 10 eV. However, only molecular ions are observed with MAB using N2 as the ionization gas. Temperature gradients were used to separate the products generated during the thermal degradation of a 1,6-hexamethylenediisocyanate (HDI) polyurethane paint. The analysis of mass spectra was facilitated owing to a selective desorption of pyrolysis products. Furthermore, changing the MAB ionization gas allows elucidation of the structure of the pyrolysis products by controlling the extent of their fragmentation. During these experiments, isocyanic acid, methyleneisocyanate, ethyleneisocyanate, propylisocyanate and butylisocyanate were detected. 相似文献
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文章概述了30年来刚-挠性PCB的发展。今天,凡是在刚性多层板的技术进步,同样,在刚-挠性印制板也是能够实现的。 相似文献
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A set of mono-and bimetallic(Zn-Co) supported ZSM-5 catalysts was first prepared by PEG-additive method. The physicochemical properties of the catalysts were investigated by FTIR, XPS, XRD, N_2adsorption-desorption measurements, SEM, EDS and NH3-TPD techniques. The physicochemical properties showed that the Zn Co_2O_4 spinel oxide was formed on the ZSM-5 support and provided effectual synergetic effect between Zn and Co species for the bimetallic catalyst. Furthermore, bimetallic supported ZSM-5 catalyst exhibited weak, moderate and strong acidic sites, while the monometallic supported ZSM-5 catalyst showed only weak and moderate or strong acidic sites. Their catalytic performances for thermal decomposition of hexamethylene–1,6–dicarbamate(HDC) to hexamethylene–1,6–diisocyanate(HDI) were then studied. It was found that the bimetallic supported ZSM-5 catalysts,especially Zn-2Co/ZSM-5 catalyst showed excellent catalytic performance due to the good synergetic effect between Co and Zn species, which provided a suitable contribution of acidic sites. HDC conversion of 100% with HDI selectivity of 91.2% and by-products selectivity of 1.3% could be achieved within short reaction time of 2.5 h over Zn-2Co/ZSM-5 catalyst. 相似文献
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激光技术在刚挠性HDI板的应用——微导通孔形成,图形成形,外型加工 总被引:1,自引:1,他引:0
概述了采用一个激光源能够加工刚性和挠性板的一种新型激光技术,PCB制造商可能采用最小的投资和提高生产率而进入HDI市场。 相似文献
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概述了Motorola的埋入PTF电阻、CFP电容和螺旋电感等无源集成的高密度印制板和埋入无源集成技术。 相似文献