纸张喷墨印刷的网点铺展渗透研究

分析了喷墨印刷中油墨与纸张的使用情况并归纳其特点,以此特点为出发点、以能量为基础建立墨滴在纸张上的铺展、渗透模型,通过获得模型中所需参数来预测喷墨印刷的最终效果,并用分形理论评判其效果.     

相变喷墨打印质量的分析

通过分析相变喷墨工作的原理,同时根据ISO 13660标准规定的质量指标及计算方法,选取记录点直径、圆整度、长宽比,线条宽度、线条边缘模糊度、线条边缘粗糙度等,作为质量检测要素。利用CCD捕获图像质量要素并使用图像质量分析与评价软件,客观、定量地分析了相变喷墨打印质量。测量结果表明:相变喷墨在普通纸张上可以实现高质量的打印结果;记录介质表面平滑度对相变喷墨打印的线条质量有一定程度影响。     

可变墨滴喷墨打印印刷品的光谱预测模型

在喷墨打印机喷出墨滴大小可变时,以Clapper-Yule模型为基础,研究了可变墨滴喷墨打印印刷品的反射率预测模型。首先引入了墨滴大小变化和Clapper-Yule模型的调频加网形式;然后,用墨滴变化引起的墨层厚度变化和调频网点大小的变化扩展Clapper-Yule模型;最后,建立了墨滴大小扩展的Clapper-Yule模型,并通过模拟实验验证了模型的优越性。     

喷墨技术新进展

喷墨打印机的喷墨方式主要有两种 ,热泡式喷墨 ,ＨＰ和ＣＡＮＯＮ为代表 ;微压电式喷墨 ,ＥＰＳＯＮ为代表。1　Ｃａｎｏｎ公司的微小墨滴调整及多重色控技术喷墨打印机就是将彩色液体形成的墨滴 ,以极高的速度喷射到打印介质上 ,墨滴的组合形成了文字和图形。墨滴的大小、形状、原料、浓度、定位等因素 ,对影像的打印质量影响很大。1 1　微小墨滴调整技术打印机喷射的墨滴 ,对打印速度和精度有很大影响。佳能的墨滴调整技术是在同一张图像中 ,根据不同需求喷射不同大小的墨滴 ,精细处采用小墨滴 ,确保打印质量 ,而对打印质量要求不高的地方…     

喷墨印刷膜层宽度和厚度的分析计算

喷墨印刷是一种定量精确沉积技术,能将各种材料沉积在承印材料上成膜,在制造业中有广泛的应用前景.本文通过分析墨滴初始半径、墨滴铺展半径,并结合喷墨精度等参数,给出膜层宽度和厚度的计算公式,最后分析其影响因素.     

喷墨打印新技术概述

近几年来,喷墨打印技术又有了极大的进展,本文概述一些著名厂商新开发的喷墨打印新技术,都是已经投入实际应用,并取得良好的效果。例如：准分子激光切割喷嘴生产技术,可使一个喷头上有多达400多个喷嘴,喷嘴直径大小才40纳米;防水墨水技术,使用染料性墨水,即使使用普通纸张打印,图像也能耐长时间水泡;超精微墨滴技术,使喷出的墨滴只有4微微升;色彩分层技术,不同颜色的墨滴不是并置,而是分层叠置,最多可达29叠层,使打印图象色彩更鲜艳,层次更丰富;还有边缘平滑技术、精确走纸技术、精确色彩分布技术等等。     

喷墨印刷纸上液滴的铺展机制研究

分析了喷墨印刷纸张上液滴的铺展现象,结合试验数据讨论了液滴铺展的2个过程。针对纸张表面化学异质性、粗糙度对于铺展行为的影响,结合试验数据,修正了流体动力学模型的推论。     

对喷墨印刷中油墨铺展和渗透的研究

探讨了墨滴与纸面接触后发生的相互作用:铺展和渗透, 分析了相互作用的机理;并根据Kubelka-Munk理论提出了能够确定渗透之后的光学参数的渗透模型;以及使用分形理论对油墨铺展进行模拟,能够精确确定网点面积;对喷墨印刷中其它分形应用作了初步地探讨,提出可以建立纸张涂层表面的粗糙度与墨水的光学性质和铺展性能的关联函数,进而可以分析不同印品的质量.     

喷墨印刷质量的分析与研究

详细分析了色彩管理软件、分辨率、色阶、墨滴大小、墨水、承印物等对喷墨印刷质量的影响,通过理论分析与实践经验的总结,旨在找出各因素影响喷墨印刷质量的实质以及如何控制这些因素的影响以提高印刷质量.最后,得到了7个影响喷墨印刷质量的关键因素,并提出了相应优化喷墨印刷质量措施.     

喷墨印刷质量缺陷的产生原因和解决对策

目的为提高喷墨数字印刷质量。方法用普通相机和共聚焦激光显微镜对卷筒纸喷墨数字印刷质量缺陷进行记录和对比。结果常见的数字喷墨印刷质量缺陷主要有色彩还原性差、印品单张不平("荷叶边")、图文墨迹边缘"毛刺"、印刷墨色不实、背粘、套印不准、脏污、内页增大和白条等。结论质量缺陷产生的原因是喷墨数字印刷缺乏压印过程,使用低粘度、低颜料含量的水性油墨会导致干燥速度慢和纸张吸墨性差,因此在纸张表面构筑可以精确调控单个墨滴纵向渗吸和横向铺展相对量的功能涂层是提高喷墨数字印刷质量的有效对策。     

流体粘弹性对喷墨印刷液滴参数影响

目的研究粘弹性非牛顿流体中聚合物参数对喷墨液滴形成过程中各项数据的关系,通过所得数据进行数值处理,构成关于聚合物参数变量的液滴类型空间。方法模拟实验中采用FENE-CR流体模型,将FENE-CR流体模型中的本构方程与纳维斯托克斯方程和连续介质力学相结合,推导出流体聚合物参数与流体粘弹性的关系。建立液滴喷射模型,采用Flow 3D数值模拟方法模拟聚合物参数变化对喷墨液滴形成过程的影响。结果得到了聚合物参数(聚合物延展性L、聚合浓度C和聚合物De值)对喷墨印刷中墨滴断裂过程的各项主要数据:主液滴最终速度vf、液滴尺寸V、墨尾最大长度Z,墨尾一次断裂时间tb的具体关系曲线。结论对于非牛顿粘弹性流体,虽然高分子聚合物在整个流体中所占比例很小,但是它的存在对流体粘弹性变化影响显著,聚合物种类和浓度的不同会最终导致液滴形成过程中各项数值发生巨大的变化。     

墨点形状与承印物移动速度关系实验研究

针对承印物移动速度与墨点成型关系设计了专门的实验,在承印物移动状态下实现喷墨,并检测墨点在移动承印物上的状态。 在实验过程中,喷墨头与承印物之间的距离以及墨点的飞行速度也被考虑在内。 从实验结果分析得知了在承印物移动的前提下,墨点成形的特征,从而为卷筒纸喷墨印刷机提供技术积累。     

喷墨印刷液滴的铺展特性研究

目的 研究喷墨印刷液滴相关参数对其铺展特性的影响，为喷墨印刷质量的研究奠定基础。方法 采用Fluent软件，基于VOF(Volume of Fluid)法，建立液滴撞击光滑承印物表面并铺展的仿真模型，采用PISO(Pressure-Implicit with Splitting of Operators)算法对速度和压力进行耦合，分析液滴相关参数对其撞击铺展的影响规律。结果 当液滴飞行速度为6 m/s、接触角度为40°、液滴流体黏度为0.005 Pa.s、液滴直径为0.08 mm时，液滴撞击光滑承印物表面的铺展系数最大，铺展程度最好，铺展特性最优。结论 铺展系数随液滴直径、流体黏度和接触角的增大而降低，随飞行速度的增大而增大。     

基于墨点保真度的喷墨印刷质量分析与评价

对墨点质量进行了分析,提出了以墨点保真度为评价标准的质量分析方法。介绍了基于最小覆盖圆的墨滴的理想面积,在此基础上引入了计算机图像分析法,给出了基于图像分析法的喷墨印刷质量评价方法。为喷墨印刷质量检测提出了一种简便可行的方法,此方法较传统质量分析法更为直接,适合于任意的喷墨印刷过程。     

DOD 式压电喷墨打印系统液滴形成过程的数值模拟

目的研究DOD式压电喷墨打印系统液滴形成过程。方法简化压电式喷墨打印头的几何模型,建立基于流体体积法的流体仿真模拟系统,模拟给定压力条件下液滴生成的全过程,并以此进行数值实验来评估油墨的表面张力和黏度对喷墨中液滴形成形态的影响。结果给出不同瞬间液滴的形态,得出适合于给定条件的最优参数组合。引入流体力学中的无量纲常数Z,评价表面张力和油墨黏度在耦合作用下液滴的成形状态。确定表面张力约为40 mN/m、黏度约为10 Pa·s、无量纲常数Z为4.56的油墨能够得到理想的单液滴喷射形态。结论将仿真的结果应用到实验中,对比分析可知吻合较好,证明了数值模拟的可靠性。     

Morphology control of amino acid particles in interfacial crystallization using inkjet nozzle

The aim of this study is to apply the inkjet technique to liquid–liquid interfacial crystallization. Instillation with an inkjet nozzle was compared with the batch process in order to evaluate the effectiveness of the inkjet technique for controlling particle morphology. The effects of amino acid solution concentration and organic solvent type on particle properties were investigated for instillation with an inkjet nozzle. The morphology of alanine and glycine particles was observed by scanning electron microscopy and X-ray powder diffraction. The inner structure of alanine and glycine particles was investigated by cutting particles with an ion milling machine. Controlling particle size by adjusting the droplet size in the instillation with an inkjet nozzle was found to be feasible. Most alanine and glycine particles produced by instillation were spherical, whereas most particles produced by the batch process were non-spherical. A higher concentration of amino acid in the solution may lead to the generation of solute particles at the spherical interface. It was found that the surface structure of alanine particles changed when using two kinds of organic solvents as anti-solvents. In addition, instillation allowed for β-glycine to be identified and the crystal polymorph of the particles to be controlled.     

Inkjet‐Printed High‐Efficiency Multilayer QLEDs Based on a Novel Crosslinkable Small‐Molecule Hole Transport Material

Quantum dots light‐emitting diodes (QLEDs) have attracted much interest owing to their compatibility with low‐cost inkjet printing technology and potential for use in large‐area full‐color pixelated display. However, it is challenging to fabricate high efficiency inkjet‐printed QLEDs because of the coffee ring effects and inferior resistance to solvents from the underlying polymer film during the inkjet printing process. In this study, a novel crosslinkable hole transport material, 4,4′‐bis(3‐vinyl‐9H‐carbazol‐9‐yl)‐1,1′‐biphenyl (CBP‐V) which is small‐molecule based, is synthesized and investigated for inkjet printing of QLEDs. The resulting CBP‐V film after thermal curing exhibits excellent solvent resistance properties without any initiators. An added advantage is that the crosslinked CBP‐V film has a sufficiently low highest occupied molecular orbital energy level (≈?6.2 eV), high film compactness, and high hole mobility, which can thus promote the hole injection into quantum dots (QDs) and improve the charge carrier balance within the QD emitting layers. A red QLED is successfully fabricated by inkjet printing a CBP‐V and QDs bilayer. Maximum external quantum efficiency of 11.6% is achieved, which is 92% of a reference spin‐coated QLED (12.6%). This is the first report of such high‐efficiency inkjet‐printed multilayer QLEDs and demonstrates a unique and effective approach to inkjet printing fabrication of high‐performance QLEDs.     

微纤化纤维素对喷墨打印纸涂层性能的影响

目的研究微纤化纤维素作为添加剂对喷墨打印纸涂层性能的影响。方法以胶体二氧化硅为颜料,采用聚乙烯醇为胶黏剂,通过改变微纤化纤维素的添加量(0,0.3,0.5,0.8,1份)制备5组涂料,经过涂布、干燥、压光得到5种喷墨打印涂布纸,通过对涂料的粘度、纸张的物理性能、喷墨打印质量和动态渗透性等进行分析,研究微纤化纤维素对喷墨打印纸涂层性能的影响。结果微纤化纤维素可以降低喷墨打印纸涂层的粗糙度(47%),提高喷墨打印纸涂层的表面强度(36.7%),并对喷墨打印质量和涂层渗透性有很好的改善效果,并发现表面涂层被水浸透的时间与喷墨印刷性能有很好的相关性。结论当微纤化纤维素用量为0.5份左右时,纸张的喷墨打印性能最优。     

Nanoscale patterning of colloidal quantum dots on transparent and metallic planar surfaces

The patterning of colloidal quantum dots with nanometer resolution is essential for their application in photonics and plasmonics. Several patterning approaches, such as the use of polymer composites, molecular lock-and-key methods, inkjet printing and microcontact printing of quantum dots have been recently developed. Herein, we present a simple method of patterning colloidal quantum dots for photonic nanostructures such as straight lines, rings and dot patterns either on transparent or metallic substrates. Sub-10?nm width of the patterned line could be achieved with a well-defined sidewall profile. Using this method, we demonstrate a surface plasmon launcher from a quantum dot cluster in the visible spectrum.     

Geometric confinement of directly deposited features on hydrophilic rough surfaces using a sacrificial layer

It is challenging to achieve high definition for inkjet-printed features on hydrophilic rough surfaces. In this study, a spreading diameter of ~5 mm was observed for a 10 pL inkjet droplet when it impacted onto a hydrophilic rough surface. A new geometric confinement method was employed to facilitate a much higher inkjet printing definition in the range of ~50 μm. A layer of water-soluble polyacrylic acid (PAA) was spin-coated onto a hydrophilic rough surface and then inkjet patterned. Subsequently, the PAA was made water-insoluble by subjecting the sample to a heat treatment with temperatures above 170 °C. The change in solubility of PAA during the heat treatment is found to be a crucial factor, which enables the physical confinement of the subsequently inkjet printed aqueous-based droplets. The thickness of the spin-coated sample also plays a critical role in the effectiveness of the physical confinement. The effectiveness of the proposed approach was demonstrated with an inkjet patterning process, in which a dielectric layer of 200 nm SiN _x on a textured silicon wafer was selectively etched using 10 pL inkjet-printed droplets resulting in a line width of ~75 μm. When using a 1 pL printhead, the etched line width was as fine as ~30 μm.