目的研究喷墨过程中流体物性参数对喷墨质量的影响。方法采用数值模拟方法,基于流体体积法建立仿真模型,以不同粘度和表面张力的流体为研究对象,通过分析墨滴形成及铺展过程的形态变化,探索流体的物性参数(粘度、表面张力)对于墨滴成形过程的影响,得出高质量喷墨印刷的流体物性参数范围,并在柔性基底上印刷UHF(超高频)天线来验证模拟结果的可靠性。结果使用无量纲常数Z表征流体的可喷印性能,数值模拟结果表明表面张力为40 m N/m,粘度为10 Pa·s的墨水能达到良好的喷印状态。结论通过实验观测墨水的喷射过程,与模拟结果对比具有较高的重合度,数值模拟结果可以较准确地预测墨水印刷质量,经测量可知印制天线满足使用要求。
Copper nanoparticles with a size of about 150 nm were prepared in toluene using oleic acid as protecting agent. The nanoparticles were used to prepare conductive Cu ink with a polyurethane binder. Oleic acid was used to prevent the nanoparticles from oxidization and agglomeration. The prepared Cu nanoparticles were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The resistivity of the copper film on glass substrate that was prepared using Cu nanoparticle ink reached about 1.5× 10-4 2. cm-1 after it was annealed to 120 ~C. Both the nanoparticle ink and the films were characterized by XRD, fourier transform infrared (FT-IR), and the thermogravimetry-differential scanning calorimetry instrument (TG- DSC).