导电油墨厚度对RFID标签天线辐射效率的影响

为提高RFID电子标签天线的辐射效率,从理论上分析了影响标签天线辐射效率的一系列因素,以偶极子和叠缝隙2种天线为研究对象,研究了导电油墨厚度对RFID标签天线的辐射效率的影响。结果表明:决定天线的辐射效率的是印刷标签天线所用的总油墨量,而不是整个天线结构中不同区域内油墨的分布情况。为实际RFID电子标签生产中导电油墨的控制和改进,提供一些指导。     

Printed UHF RFID antennas with high efficiencies using nano-particle silver ink

One of the most popular targets of conductive ink technology is to print RFID tag antennas. However, the printed RFID antennas, manufactured by conductive silver ink which is generally based on microsized silver particles, have lower conductivity and consequently lower radiation efficiency than those by conventional copper etching method. This work demonstrates nano-particle conductive silver ink that is capable of printing UHF RFID antennas with improved radiation efficiency. Compared with commercial micro-particle silver ink, the solid content of metal is much higher in the proposed nanoparticle silver ink, leading to better electrical properties. Two types of dipole antennas are printed with the proposed nano-particle as well as with commercial micro-particle inks. Also, the same antennas are fabricated by copper etching. With these conductive inks, a straight and a meandered dipole antennas are fabricated and their radiation efficiencies are measured with the Wheeler cap method. Experimental results show that the radiation efficiencies of the antennas based on nanoparticle silver ink are superior to those printed with the micro-particle silver ink, and are comparable to those of popular copper antennas.     

RFID丝印墨层厚度影响因素的研究

介绍了丝网印刷RFID标签天线的工艺特点;在分析了标签天线电阻的计算方法的基础上,提出了天线电阻主要受天线墨层厚度和导电油墨导电性能两方面的影响。分别分析了丝网、刮墨刀、丝网目数等因素对天线墨层厚度的影响,以及导电油墨的黏度及导电油墨的干燥效果对其导电性能的影响。为实际生产中,调整丝印RFID天线的电阻提供理论参考。     

基于电子标签导电油墨厚度的研究

在电子标签的印制中,采用分层印刷电子标签天线的思路,提出了分层蝶形天线模型,并进行了仿真模拟,研究了墨层厚度对蝶形天线辐射效率的影响。由仿真结果分析可知:不同区域电流密度的高低影响分层天线的辐射效率,在天线上找到了分层最佳点,分层天线的辐射效率比单层天线高。解决了印刷天线墨层厚度与辐射效率矛盾的问题。     

无线射频识别技术用导电油墨的研究

介绍了无线射频标签(RFID)及其制作方法、工作原理和应用领域,阐明了RFID天线与导电油墨之间的关系,重点对导电油墨的组成、分类、不同体系油墨的特点进行了阐述,并对无机系、有机系和复合型三大类导电油墨的国内外研究现状做了详细的阐述和对比分析,指出了这三类油墨的特点和发展趋势,其中复合型导电油墨以其独特的优势,在导电油墨未来的研究和应用领域中,将替代传统的有机、无机系导电油墨,成为导电油墨的主导及RFID天线制作材料的首选.     

Synthesis of monodisperse silver nanoparticles for ink-jet printed flexible electronics

In this study, monodisperse silver nanoparticles were synthesized with a new reduction system consisting of adipoyl hydrazide and dextrose at ambient temperature. By this facile and rapid approach, high concentration monodisperse silver nanoparticles were obtained on a large scale at low protectant/AgNO(3) mass ratio which was highly beneficial to low cost and high conductivity. Based on the synthesized monodisperse silver nanoparticles, conductive inks were prepared with water, ethanol and ethylene glycol as solvents, and were expected to be more environmentally friendly. A series of electrocircuits were fabricated by ink-jet printing silver nanoparticle ink on paper substrate with a commercial printer, and they had low resistivity in the range of 9.18 × 10( - 8)-8.76 × 10( - 8) Ω m after thermal treatment at 160?°C for 30 min, which was about five times that of bulk silver (1.586 × 10( - 8) Ω m). Moreover, a radio frequency identification (RFID) antenna was fabricated by ink-jet printing, and 6 m wireless identification was realized after an Alien higgs-3 chip was mounted on the printed antenna by the flip-chip method. These flexible electrocircuits produced by ink-jet printing would have enormous potential for low cost electrodes and sensor devices.     

纳米银导电油墨及其在柔性印刷电子中的应用

目的 探究纳米银导电油墨及其在柔性印刷电子中的应用。方法 通过总结国内外文献,从纳米银颗粒及其导电油墨的制备、印刷工艺、烧结工艺以及在柔性印刷电子技术中的应用几方面总结近年来的研究进展。结果 在油墨制备及使用中,简化制备工艺、降低生产成本、实现绿色环保、低温烧结,同时提高油墨的基材适应性是未来纳米银导电油墨的改进重点。直写技术具有精度高、速度快等优势,正逐渐替代丝网印刷技术成为主流。烧结工艺的研究重点在于实现低温烧结,其中化学烧结工艺简单,但提高导电性是研究重点。其他烧结方式则设备昂贵,环境要求高。结论 作为功能性电子材料,纳米银导电油墨因出色的电性能和印刷适性,正在被广泛应用于柔性印刷电子中。近年来通过对纳米银及其导电油墨的深入研究及技术改进,在纳米银颗粒的制备、低温烧结技术、节能环保加工工艺等方面获得了一定的进展。与此同时,将其作为功能材料应用于制备柔性传感器中,RFID标签天线、柔性电极、超级电容器、太阳能电池等正受到广泛研究与应用。     

基于喷墨印刷的RFID标签天线性价比优化方法研究

以小型偶极子天线为研究对象,采用无选择和选择性2种不同的喷墨印刷方式印制,对比了2种印刷方式下天线的识别距离和油墨耗用量。实验证明,在表面电流密度较高处进行选择性印刷,以增加墨层厚度的方法,有利于降低喷墨印制无源超高频RFID标签天线的成本,性价比明显提高。     

纳米铜导电油墨的制备及其应用

综述了纳米铜粒子的制备方法,即机械球磨法、辐射合成法、物理气相沉积法等物理制备法及化学制备法,探讨了改进纳米铜导电油墨防氧化、低温烧结、导电性能等关键问题,以及纳米铜导电油墨在印刷RFID电子标签、薄膜开关、触摸屏等方面的应用,并提出纳米铜导电油墨未来的研究方向为：抗氧化、低温烧结、多种印刷方式及产品应用等研究。     

Performance characterization of screen printed radio frequency identification antennas with silver nanopaste

The era of wireless communication has come and it is going to flourish in the form of radio frequency identification (RFID) tags. The employment of RFID tags in daily commodities, however, is constrained due to the manufacturing cost. Therefore, industries in the field have sought for alternative manufacturing methods at an ultra low cost and various printing processes have been considered such as inkjet, gravure, flexo, off-set and screen. Although such printing processes are age-old, their applications have been mainly limited to graphic arts and design rules for electronic appliances have not been fully established yet. In this paper, the selection of ink and printing process to fabricate RFID antennas is discussed. The developed silver nanopaste in the range of 20 to 50 nm without the inclusion of microparticles and flakes was sintered at 120 °C for 1 min, which is lower than that of conventional silver paste with microparticles and flakes, and its resistivity was found to be approximately 3 μΩ cm. The radiation performances of various screen printed RFID antennas with silver nanopaste were found comparable to those of copper etched ones.     

生态导电油墨及其在包装领域的应用研究进展

导电油墨的制备已成为加快印刷电子发展的重要技术之一,近年来符合生态理念的导电油墨逐渐成为研究热点。通过对生态导电油墨的相关文献进行分析与梳理,综述了生态导电油墨的研究现状、导电机理和应用方向。归纳出生态导电油墨主要可分为溶剂型和能量固化型两类,总结了生态导电油墨在智能包装中的应用,如：印刷柔性电池、电子交互包装、RFID标签、薄膜开关等,此类产品为包装在智能交互、信息追踪溯源、防伪防盗等方面提供强力的技术支持。     

导电油墨及其印刷技术的研究进展

目的 综述导电油墨及其印刷方式的研究进展,为开发价格低廉、性能稳定、导电性优良的导电油墨提供参考。方法 通过查阅文献归纳各类导电油墨的制备方式、印刷方式和应用领域,对导电油墨进行系统分类,比较各类导电油墨的性能和优缺点,并对其印刷技术进行分析,展望了导电油墨的发展前景。结果 目前关于导电油墨的研究集中在纳米银、纳米铜、石墨烯等导电填料的低温烧结油墨,主要采用丝网印刷、喷墨印刷等印刷方式,多用于制备传感器、柔性可穿戴设备等。未来的研究仍需关注如何低成本、低能耗、简单大量地制造导电油墨。结论 导电油墨的制备将与环境友好型的印刷方式相结合,向高导电性、高印刷适性发展,成为印刷电子领域的关键技术。     

银墨内衬纸复合工艺参数研究

目的确定凹印纸铝复合的印刷速度和压力,为凹印银墨印刷生产烟标内衬纸提供基础生产数据。方法以幅宽650mm凹印复合机为基础,进行内衬纸原纸和银墨的复合印刷,并在预实验过程中采集数据,并通过插值拟合法对实验数据进行处理,确定最佳印刷速度和印刷压力。结果根据油墨转移量的实验结果可以得出,在1000 r/min,3 MPa条件下得到较好的油墨转移量;对上机实验所得的实验结果进行插值拟合,插值并进行十阶拟合计算后得出,在1050 r/min,2.79 MPa时,内衬纸表面银墨油墨转移量效果最佳。结论初步验证了凹印印刷银墨进行烟标内衬纸的可行性,为烟标内衬纸复合提供了一种新的复合思路和方法。     

Properties of polyacrylic acid-coated silver nanoparticle ink for inkjet printing conductive tracks on paper with high conductivity

Silver nanoparticles with a mean diameter of approximately 30 nm were synthesized by reduction of silver nitrate with triethanolamine in the presence of polyacrylic acid. Silver nanoparticle-based ink was prepared by dispersing silver nanoparticles into a mixture of water and ethylene glycol. The mechanism for the dispersion and aggregation of silver nanoparticles in ink is discussed. The strong electrostatic repulsions of the carboxylate anions of the adsorbed polyacrylic acid molecules disturbed the aggregation of metal particles in solutions with a high pH value (pH > 5). An inkjet printer was used to deposit this silver nanoparticle-based ink to form silver patterns on photo paper. The actual printing qualities of the silver tracks were then analyzed by variation of printing passes, sintering temperature and time. The results showed that sintering temperature and time are associated strongly with the conductivity of the inkjet-printed conductive patterns. The conductivity of printed patterns sintered at 150 °C increased to 2.1 × 10⁷ S m⁻¹, which was approximately one third that of bulk silver. In addition, silver tracks on paper substrate also showed better electrical performance after folding. This study demonstrated that the resulting ink-jet printed patterns can be used as conductive tracks in flexible electronic devices.     

基于导电银浆流变特性的导线印刷品质分析与控制

提出了高精度电子产品印刷品质的评价指标,然后根据银微粒在银浆聚合物基体中的受力情况,分析了导电银浆的流动性和触变性对导线印刷品质的影响和墨膜中的银微粒体积分数与浆体流变特性之间的关系,进而提出了银浆中银微粒填充量及墨膜干燥状态是影响导线印刷品质的主要因素.通过大量实验样本的分析和评价,提出了确定银浆中银微粒渗流阈值及墨膜最佳干燥条件的目的和方法,为有效控制导线印刷品质提供了理论支持和实践指导.     

喷墨印刷工艺对导电墨水导电性能的影响

目的研究喷墨印刷工艺对导电墨水导电性能的影响。方法以EPSON 1390万能平板打印机为输出设备,选取塑料薄膜种类、打印分辨率、打印次数、电路形状为主要工艺指标,运用单因素实验法,测试不同指标作用下各印刷线路的单位电阻值。结果塑料薄膜的表面分子结构对墨水的导电性能有直接影响,表面张力高的塑料有利于获得较好的印刷效果,导电性会得到提高;较高的打印分辨率有利于提高墨层的连接精度,从而提高导电性;适当增加打印次数有利于形成清晰完整的印刷电路,可以降低平均电阻值;印刷电子线路形状不同,导电性能也不尽相同,导电性能顺序为直线型折线型矩形波型环型。结论喷墨印刷工艺对导电墨水的导电性能具有一定的影响,选择合适的印刷工艺有利于提高导电线路的导电性。     

Organic thin film transistor using silver electrodes by the ink-jet printing technology

We have developed a conductive ink containing silver nanoparticles from which the electrodes for organic thin film transistor were directly patterned by ink-jet printing. Nano-sized silver particles having ∼ 20 nm diameter was used for a direct metal printing. Silver conductive ink was printed on the heavily doped n-type silicon wafer with 200-nm thick thermal SiO₂ layer as a substrate. To achieve a high line resolution and smooth conductive path, the printing conditions such as the inter-drop distance, stage moving velocity and temperature of the pre-heated substrates were optimized. After the heat-treatment at temperatures of 200 °C for 30 min, the printed silver patterns exhibit metal-like appearance and the conductivity. To fabricate a coplanar type TFTs, an active material of semiconducting oligomer, α,ω-dihexylquaterthiophene (DH4T) in a chlorobenzene was deposited between the ink-jet printed silver electrodes by drop casting. The OTFT with the ink-jetted source/drain electrodes shows general performance characteristics with good saturation behavior and no significant contact resistance as compared to the one with vacuum deposited electrodes. The electrical characteristic parameters of OTFT show the mobility of 1.3 × 10^− 3 cm² V^− 1 s^− 1 in the saturation regime, on/off current ratio over 10³, and threshold voltage of about − 13 V.     

Direct writing of copper conductive patterns by ink-jet printing

Ink-jet printing of metal nanoparticles is an attractive method for direct patterning conductive metal lines owing to low-cost, low-waste, and simple process. While most of the researches here focused on novel metals such as gold and silver, we have developed a conductive ink containing copper nanoparticles as an alternative that is inexpensive conductive material. Copper particles with a size of 40-50 nm were synthesized by polyol process, from which the well-dispersed conductive ink with low viscosity was prepared. We have successfully demonstrated a direct writing of the conductive lines using Cu conductive ink. The ink-jet printed copper patterns exhibited metal-like appearance and became highly conductive upon heat treatments. The resistivity of the film reached to 17.2 μΩ cm at 325 °C for 1 h in vacuum.     

Inkjet printing of multi-walled carbon nanotube/polymer composite thin film for interconnection

In this paper, multi-walled carbon nanotube (MWCNT) ink was selectively patterned by inkjet printing on substrates to form conductive traces and electrodes for interconnection application. MWCNT was firstly functionalized using concentrated acid and dispersed in deionized water to form a colloidal solution. Various concentrations of MWCNT were formulated to test the stability of the solution. The printability of the MWCNT ink was examined against printing temperature, ink concentration and ink droplet pitch. Rheological properties of the ink were determined by rheometer and sessile drop method. The electrical conductivity of the MWCNT pattern was measured against multiple printing of MWCNT on the same pattern (up to 10 layers). While single layer printing pattern exhibited highest resistance, the CNT entangled together and formed a random network with more printed layers has higher conductivity. The electrical properties of the printed film was compared to a composite ink of CNT and conducting polymer (CNT ink was mixed with conductive polymer solution, Poly(3,4-ethylenedioxythiophene)-Poly(styrenesulfonate) (PEDOT:PSS)). Scanning electron microscopy (SEM) was used to observe the surface structure and atomic force microscopy (AFM) was used to study the morphology of the printed film under different conditions.     

Thermal characterization of screen printed conductive pastes for RFID antennas

Thermal resistance is an essential aspect of electronic circuits designing. It leads to unexpected changes in electronic components during their work. In this study, new materials for screen printed RFID tag's antennas were characterized in terms of their resistance to thermal exposure. Polymer materials containing silver flakes, silver nanopowder, carbon nanotubes or conductive polymer PEDOT:PSS were elaborated and used for antenna printing on flexible materials. In order to verify their long term susceptibility to damages caused by the changing environmental conditions, the temperature cycling test was used in three different temperature ranges: +65 °C, −12 °C, −40 °C/+85 °C (3 h in each temp., dwell time 1 h). The highest durability to thermal exposure exhibited the paste with carbon nanotubes dispersed in poly(methyl methacrylate) PMMA and the lowest one – the paste with conductive polymer PEDOT:PSS.