Direct Toner Printing: A Versatile Technology for Easy Fabrication of Flexible Miniaturized Electrodes

We reported here three simple, low cost and easy to accomplish strategies for the fabrication of microelectrodes and other conductive patterns using ordinary office laser‐printers. In this work, toner patterns were directly printed onto the flexible substrate, acting as a mask to create the intended conductive design. To highlight the versatility of such technology, toner‐printed patterns were employed in two diverse ways: one in which the patterned toner had the exact design of the electrode and other employing a reverse toner‐printed pattern. The first one was used for the adaptation of the well‐known printed circuit board (PCB) fabrication technique, but using direct toner printing (DTP) in an already conductive flexible substrate. The second was employed for the two remaining strategies: one based on the deposition of conductive film, followed by lift‐off process; and another based on drop‐casting of a conductive ink into the formed toner cavities, followed by thermal cure. As proof‐of‐concept, all three DTP strategies were used for the fabrication of miniaturized gold electrodes in polyimide substrate, and electrochemical performance of each obtained electrode was evaluated by cyclic voltammetry. Insights about DTP technology, alignment issues, advantages, limitations and resolution of each presented approach were provided. Finally, direct toner printing showed to be a simple, affordable and quite promising technology for the fabrication of low cost point‐of‐care electrochemical devices using flexible platforms.     

光敏热显成像材料概述

本文综述了近十多年来国际感光界关注热点之一的光敏热显成像材料(Photothermographic materials,简称PTG)的研究情况.重点介绍了羧酸银、卤化银、调色剂、防灰雾剂与稳定剂、光谱增感剂以及粘合剂等PTG材料的主要组分,并对PTG材料成像机理的研究情况进行了评述.     

激光共聚焦扫描显微镜对激光打印文件墨粉厚度的分析研究

使用激光共聚焦扫描显微镜,对六种品牌和型号的激光打印机分别在打印纸和高光相纸上打印的图文墨粉厚度进行测量。结果表明,测量普通打印纸张上激光打印形成墨粉厚度时,测量数据因纸张纤维凹凸不平的影响有一定波动,相纸上激光打印形成的墨粉厚度测量数据相对稳定,并总结出随着打印文件图文线条宽度与墨粉厚度的变化规律。实验表明激光打印文件墨粉厚度的数据测量具有可行性,同一台激光打印机的打印文件墨粉厚度相对稳定,该指标作为一种重要参数可以为激光打印文件检验提供量化依据,并为打印机的同一认定提供依据。     

烟酸在热敏成像材料中的调色作用

本文将烟酸引入以硬脂酸银为银源的热敏成像材料中,可以明显提高显影密度,并使影像颜色由金黄色变成黑色;同时显影银粒子的尺寸变大、形貌也会发生改变,并且显影银粒子像链珠一样排成一条线,而线与线之间基本上是平行排列的.进一步实验结果表明,烟酸的引入会降低材料的pH、pAg值和银盐的相变温度,硬脂酸银与烟酸一起加热可能反应生成了新的化合物.     

Effect of Composition on Surface Properties of Polydimethylsiloxane-based Inorganic/Organic Hybrid Films

Surface properties of the polydimethylsiloxane (PDMS)-based inorganic/organic hybrids films prepared from silanol-terminated PDMS and titanium tetra-isopropoxide (TIP) were investigated with an aim at the application to the thermal-fixation roll for electro-photographic printers. The 300°C-treated hybrid film with the PDMS/TIP molar ratio of 0.5 exerted a relatively high contact angle of water as 115°C. It was found by using Tapping-Mode Atomic Force Microscopy (AFM) that the hybrid film surface changed from lamella structure to sea-island structure with the increase of PDMS content when heat-treated at 150°C, and became homogenous surface over 300°C. The phase-shift detected by AFM was negative shift, showing that hybrid surface became more hydrophobic as the PDMS/TIP molar ratios of 0.35 and 4.0 exhibited excellent toner-offset property of showing no adhesion of toners, suggesting their practical use in the photographic printers.     

裂解气相色谱/质谱法检验复印墨粉

复印墨粉检验分析在经济案件侦查以及墨粉配方研究方面具有十分重要的意义。采用裂解气相色谱技术,对收集到的复印墨粉进行分离分析,并用裂解气相色谱/质谱联用技术,对所得裂解峰进行归属。分析结果的重复性与稳定性良好,复印件上墨粉与原墨粉分析结果一致。对不同厂家与牌号的墨粉进行区分与归类,为墨粉鉴别提供了依据。     

高速乳化对悬浮聚合墨粉形貌和性能的影响

以铁黑为颜料粒子,采用悬浮聚合技术,通过高速乳化机对反应体系进行预分散,制备出平均粒径为12μm的球形墨粉颗粒.通过在反应体系中加入span-80,克服铁黑粒子在墨粉表面的趋附现象.研究了乳化速度对墨粉颗粒性能的影响.     

Forensic discrimination of photocopy and printer toners. III. Multivariate statistics applied to scanning electron microscopy and pyrolysis gas chromatography/mass spectrometry

Copy toner samples were analyzed using scanning electron microscopy with X-ray dispersive analysis (SEM–EDX) and pyrolysis gas chromatography/mass spectrometry (Py–GC/MS). Principal component and cluster analysis of SEM data for 166 copy toner samples established 13 statistically different subgroups, with the presence or absence of a ferrite base being a major division. When toners were compared for which both SEM and reflection–absorption infrared spectral data were available, 41% of the samples could be assigned to specific manufacturers. Py–GC/MS on poly(styrene:acrylate)-based toners produced eight peaks relevant to toner differentiation. One third of the toners clustered in a small group that contained five statistically different subgroups. Of the 57 toners for which both Py–GC/MS and SEM data were available, 31 could be differentiated using the combined analytical results. The synergy of the complementary information provided by Py–GC/MS and SEM narrows matching possibilities for forensic investigations involving copied or laser printed documents.This is publication number 03-04 of the Laboratory Division of the Federal Bureau of Investigation. Names of commercial manufacturers are provided for identification only, and inclusion does not imply endorsement by the Federal Bureau of Investigation.     

基于羧酸银的光敏热成像技术进展

最近10年,光敏热显影成像材料在技术上取得了重要进展,特别是以羧酸银作为银源的这类材料.这些进展集中体现在1995年为满足商品需要而研制成功的世界上第一个具有高分辨力、可作诊断使用的医用X射线胶片的Kodak DryView激光成像片上.此后,采用同样技术的一类特殊片种,即高反差的印刷胶片也随之问世.这些产品的实践应用都相当成功,已被多家公司所采用.这些新产品得益于三个方面的技术进展:改进成像层的照相性质、高影像质量和低成本的激光成像硬件,这也是此研究工作的焦点.在这类材料上所取得的重要成就反映在它们的高分辨力、高最大密度、低最小密度以及整张胶片性质的均一性上.所有这些优点,再加上超过100年的影像稳定性,使原来“老”的光敏热显影技术发生了一次脱胎换骨的变化,成为了当今最新的一种硬拷贝成像介质.     

Forensic discrimination of photocopy and printer toners II. Discriminant analysis applied to infrared reflection-absorption spectroscopy

Copy toner samples were analyzed using reflection-absorption infrared microscopy (R-A IR). The grouping of copy toners into distinguishable classes achieved by visual comparison and computer-assisted spectral matching was compared to that achieved by multivariate discriminant analysis. For a data set containing spectra of 430 copy toners, 90% (388/430) of the spectra were initially correctly grouped into the classifications previously established by spectral matching. Three groups of samples that did not classify well contained too few samples to allow reliable classification. Samples from two other pairs of groups were similar and often misclassified. Closer examination of spectra from these groups revealed discriminating features that could be used in separate discriminant analyses to improve classification. For one pair of groups, the classification accuracy improved to 91% (81/89) and 97% (28/29), for the two groups, respectively. The other pair of groups were completely distinguishable from one another. With these additional tests, multivariate discriminant analysis correctly classified 96% of the 430 R-A IR toner spectra into the toner groups found previously by spectral matching.This is publication number 03–03 of the Laboratory Division of the Federal Bureau of Investigation. Names of commercial manufacturers are provided for identification only, and inclusion does not imply endorsement by the Federal Bureau of Investigation.