丝印织物基UHF-RFID标签的耐机洗性及涂层优化

Machine washing endurance and coating of UHF-RFID tags based on screen-printed antenna on fabric

为探究机洗的应力作用对工业化丝印织物基超高频射频识别(ultra high frequency-radio frequency identification,UHF-RFID)标签的破坏作用以及涂层对标签的保护机理,采用紫外固化聚氨酯丙烯酸酯(PUA)涂覆天线,通过弯曲和扭转变形模拟机洗中的应力作用,分析涂层厚度对天线耐机洗性的影响;用聚二甲基硅氧烷(PDMS)涂覆芯片绑定区域,对比研究天线无涂层而芯片绑定区有涂层、天线有涂层而芯片绑定区无涂层以及全涂层标签的耐机洗性。结果表明:模拟机洗试验中,弯曲作用比扭转作用对天线导电层的破坏效应更大,且涂覆2层PUA对天线导电层的保护作用相对较好;标准机洗试验中,芯片绑定区域涂覆PDMS有助于提高标签的耐机洗性,且芯片周围由应力集中引起的天线导电层断裂是机洗失效的主要原因,而绑定界面的松动或芯片的脱落属于次要原因。

To explore the stress effect of machine washing on the destruction of industrial screen-printed fabric-based ultra high frequency-radio frequency indentification(UHF-RFID)tags and the protective mechanism of the coating on the tags,UV-cured polyurethane acrylate(PUA)was used to coat the antenna.And the stress effect in machine washing was simulated by bending and torsional deformation to analyze the effect of coating thickness on the antenna s resistance to machine washing.The chip-bound area of the tag was coated by polydimethylsiloxane(PDMS).The machine-washing endurance of the tags with antenna uncoated while chip-bound area coated,with antenna coated while chip-bound area uncoated,and with the both coated were studied.The results show that,in the simulated washing test,bending is more destructive to the antenna conductive layer than twisting,and the protection of the antenna conductive layer is relatively good with two layers of PUA coating.In the standard washing test,PDMS coating in the chip-bound area helps to improve the machine-washing endurance of the tags.The main cause of the washing failure is the fracture of the antenna conductive layer caused by the stress concentration around the chip,while loosening of the bonding interface or loss of the chip is the secondary cause.