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。     

丝网版印制装饰画中的几个关键技术

根据在丝网印刷实践中的摸索与研究,对装饰画丝印工艺中的原稿质量、网点线数、网版目数、丝网颜色、油墨适性等几个重要参数进行了分析,并对与其相关的关键技术进行了讨论,其结论对丝网印刷生产和丝网版画制作有一定的指导意义.     

无源RFID标签天线的丝网印刷墨层厚度分析

结合丝网印刷墨层厚度的各主要影响因素.分析了理论墨层厚度和实际墨层厚度与网版目数的关系,建立了网版静态及受压变形两种状态下的墨层厚度计算模型,拟合了网版目数和实际墨层厚度之间的关系曲线,并选择合适的丝网印刷工艺参数,印刷制作了两款无源RFID标签天线,通过天线电阻值的波动情况分析,论证了用丝网印刷工艺制作无源RFID标签天线的品质可靠性.     

丝网印刷油墨选择与使用

由于丝网印刷工艺用途广泛 ,投入少 ,其他印刷方法难于印刷的承印物 ,都使用丝网印刷 ,因而丝网工艺近十几年得到飞速发展。带来丝网印刷工艺如此优良特点是除了多样化印刷设备外 ,还有多功能、多用途丝印油墨。因此正确选择与使用丝印油墨比选择其他印刷方法 (凹版、凸版、平版、柔性版 )显得更为重要。一、丝印油墨的选择与使用丝印刷油墨与其他类型油墨一样都是同颜料、树脂、溶剂、助剂混合研磨而成的。1 按干燥方式可分为 :蒸发干燥型———通过溶剂挥发使油墨成膜粘着方法。氧化聚合型———通过氧化反应使油墨成膜粘着方法。二液反应…     

利用丝网印刷优势在包装印刷中进行仿金属蚀刻印刷的工艺探讨

针对如何提高包装印刷产品的装潢档次，阐明了丝网印刷的工艺原理和优势，以及利用丝网印刷进行仿金属蚀刻印刷的工艺参数、技术特点，并分析了其在具体生产过程中的工艺可行性和适用范围。     

也谈丝网印刷

凹版印刷、凸版印刷、平版印刷和丝网印刷是传统的四大印刷。其中,丝网印刷早在十七世纪就起源于亚洲,在中国已有上千年的历史,丝印工艺是最古老的印刷之一。起初,丝印主要用来印刷纺织品。因其主要是手工操作、速度慢、精度低、稳定性差,以及靠经验、靠人多等原因,在中国一直被视为难登大雅之堂的落后印刷工艺,没有得到很好的发展。     

无源RFID标签天线印刷工艺品质的数学模型研究

分析了无源RFID标签天线印刷制造过程中存在的问题,提出了用多元线性模型控制印刷工艺品质的思路,并针对印刷网版目数和墨层厚度两个工艺参数,构建了与天线总阻抗之间关系的线性回归数学模型.     

高频RFID标签天线丝网印刷工艺

目的研究不同丝网印刷工艺对RFID标签性能的影响,得到最优丝网印刷工艺条件组合。方法研究印刷速度、刮印压力、刮印角度、固化条件等参数变化对天线性能参数的影响。结果当刮刀速度为50~70 m/min时,天线的阻抗稳定,印刷成品质量好,天线的可识别距离最大;刮印压力的最优值为100 N/m左右,刮刀角度应大于40°,固化温度大于110℃,固化时间应在20~40 min之间。结论标签阻抗随刮刀速度呈现U形变化,而最大识别距离呈现相反趋势;标签阻抗随刮刀压力和刮刀角度均成U形变化趋势;天线阻抗随着固化时间和固化温度的升高而降低,最大识别距离呈现相反趋势。     

基于无源RFID标签天线的印刷质量评价模型研究

为评价无源RFID标签天线的印刷质量,对无源RFID标签天线的质量性能进行了理论分析。针对成品后的天线性能与仿真后的天线性能间存在的差异,在丝网印刷的条件下,以RFID标签天线间的间隙偏差、天线厚度偏差和最大阅读距离偏差为自变量,建立了评价无源RFID标签天线印刷质量的数学线性回归模型,为RFID标签天线在生产过程中的优化提供了一定指导。     

桑印机连线丝网印剧技术在烟包上的应用

烟标作为现在中国印刷技术的一个代表，它具有较高的观赏价值和艺术价值。随着人们生活质量的不断提高，单一的印刷工艺印品已经渐渐不再适应现在的市场要求，为了追求更加精美的产品，需要有新型的印刷工艺来提高包装的档次，经过长时间的探索、研究和经验积累。更多的复合式印刷工艺开始应用到了烟标的生产当中，如柔印与丝印的复合式印刷即在柔印线上加装滚筒丝印。柔印由于是连线式生产，经一条生产线后即可出来完全的成品，这样就大大地节省了离线式的损耗。丝印工艺印刷出来的印品墨层厚实、饱满，立体感强，可以应用很多UV油墨来得到特殊的艺术效果，从而大大提高了包装的档次。两者的结合更好地适应了烟标市场的发展。随着包装印刷向高品质、高效率和多样化方向的发展，柔印连线丝网印刷已成为当今经济、技术含量较高的包装网印技术，并广泛应用在许多高档包装印刷领域和标签印刷领域。     

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。     

Design of high-Q UHF radio-frequency identification tag antennas for an increased read range

In order to increase the radio-frequency identification (RFID) operation distance, read range analysis was performed based on a simple equivalent circuit of the ultra high frequency (UHF)-band passive RFID tag. The analysis shows that a tag with a large Q-factor leads to an increased input voltage in the tag chip and thus enhances the efficiency. Based on this analysis, a compact (37.5 mm 44 mm) RFID antenna employing inductive coupling between the radiation and feeding portions was designed. Simple adjustments of the two structural parameters of the antenna allowed for easy control of the antenna resistance and inductive reactance, from which a high Q-factor requirement could be readily satisfied. For a conjugate match to the tag chip impedance of 11-j127 Omega, a Q-factor of 11.5 was achieved. The designed RFID tag has a 3 dB radar cross-section (RCS) bandwidth of 6.5 , which is wide enough to handle the impedance detuning caused by the material properties of the attached objects. The designed RFID tag antenna was fabricated and a reading range test in an anechoic chamber was performed using two methods. When a measured RCS of the RFID tag was used, the detection distance was 9.8 m for a reader sensitivity of 65 dBm and 4.7 m for a tag sensitivity of 11 dBm. Using a commercially available tag chip, the range test resulted in 4.3 m, which is compatible with the derived range equations. The tag antennas having lower Q-factors (77+j100 Omega and 55+j155 Omega) have also been fabricated, and their measured read ranges were 2.6 and 1.1+m, respectively.     

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。     

Analysis on the platform-tolerant radio-frequency identification tag antenna

A new passive radio-frequency identification (RFID) tag antenna for the ultrahigh frequancy band is proposed. It consists of a modified inductive feed and a radiating slotted copper trace (SCT). A ground plane is used in the design to make the tag antenna platform-tolerant. The radiating SCT is investigated first, and its return loss, antenna efficiency and radiation pattern characteristics are studied. The read range, differential radar cross section, input impedance and current distribution of the RFID tag that employs the SCT antenna are simulated, and reasonably a good agreement between the simulated and measured results is obtained.     

Analysis and characterization of transponder antennae for radio frequency identification (RFID) systems

An investigation into the use of various radio frequency identification (RFID) antenna designs was performed. Passive RFID tag antennae with a resonant frequency range of 902–928 MHz were tested for robustness and efficiency in the Packaging Science RFID Laboratory at the University of Florida. Commercially available single‐ and dual‐dipole tags were examined for read performance. Electromagnetic modelling software was used to model the impedance matching and detuning effects of nearby conducting surfaces. s‐Parameters, current densities and polar plots of various dipole designs were estimated. Strategies used to shorten antenna length, such as capacitive loading, were evaluated. A simple half‐wave dipole antenna was modelled in order to determine the effect of length on resonant frequency and performance. Parameter sweeps showed that a length of 14.4 cm was required for resonance at 915 MHz and 50 Ω termination. Capacitive loads shortened the dipole to 8.4 cm while adding 4.2 cm to height. It was verified that a conducting surface, such as metal packaging, had strong detuning effects on RFID tag antennae. Different methods, such as tuning stubs, alleviated the detuning effects by allowing bandwidths twice as large as with a simple dipole. Finally, the rationale for commercially available RFID antenna designs was discussed. It was found that analysis of actual antenna tag structures in the laboratory and exploring different methods to improve efficiency can lead to improvements in RFID performance. Copyright © 2005 John Wiley & Sons, Ltd.     

Graphene-Based RFID Tag Antenna for Vehicular Smart Border Passings

Globalization has opened practically every country in the globe to tourism and commerce today. In every region, the volume of vehicles traveling through border crossings has increased significantly. Smartcards and radio frequency identification (RFID) have been proposed as a new method of identifying and authenticating passengers, products, and vehicles. However, the usage of smartcards and RFID tag cards for vehicular border crossings continues to suffer security and flexibility challenges. Providing a vehicle's driver a smartcard or RFID tag card may result in theft, loss, counterfeit, imitation, or vehicle transmutation. RFID sticker tags would replace RFID tags as vehicle border passes to solve the mentioned problem. The RFID sticker tag adheres to the windscreen, side screen, dash, hood, or door of the vehicle, or any other acceptable location. Any damage or stripping from the installed location may cause data corruption and cannot be reused. Overall, these sticker tags will make the border crossings more secure and efficient. This article focuses on designing a rectangular-shaped RFID sticker tag antenna made of graphene sheets as a possible solution for smart border crossings. The proposed antenna is mathematically designed and analyzed with CST software to determine the optimum parameters. The design parameters are then used to create an antenna on a prepared graphene sheet. The performance results are carried out with CST software and a network analyzer. The designed RFID antenna stick on a car windscreen offers approximately 900 MHz bandwidth over the frequency range from 1.8 GHz to 2.7 GHz with an average gain of 1.23 dBi at the frequency to be used of 2.4 GHz microwave RFID band. The radiation is an omnidirectional pattern. The proposed graphene-sheet rectangular-shape monopole antenna is compact, low-cost, and bendable to fit into the windscreen of a car while retaining excellent wave propagation capabilities. These findings illustrate the suggested antenna's potential as an RFID tag antenna in a vehicular smart border pass system.     

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.     

Matching radio frequency identification tag compact dipole antennas to an arbitrary chip impedance

A method for matching dipole antennas to capacitive or inductive arbitrary complex impedances is proposed for ultra high frequency radio frequency identification (RFID) tag antenna designs. It can be applied to straight, capacitive-loaded, meander or any small high-Q dipole topology. For this purpose, design stages are provided with the corresponding formulas. The reflection coefficient simulations and measurements of four implemented prototypes show the expected output when the RFID frequency band, bandwidth, chip impedance and maximum tag size are required as inputs for the method. The eventual S11 < 10 dB bandwidth depends on the chip impedance Q factor and the antenna size. How this bandwidth is manifested in terms of the read range is also discussed. A length ratio of up to 31.1% regarding the standard Λ/2 dipole at resonance is obtained.