When one writes by a pencil, thin flakes of graphite are left on a surface. Some of them are only one atom thick and can be viewed as individual atomic planes cleaved away from the bulk. Such one atom thick crystals of graphite (dubbed graphene) turned out to be the strongest crystals available to us, the most conductive, most thermally conductive, most elastic, flexible, transparent material, etc, etc, etc. Its electronic properties are particularly exciting: its quasiparticles are governed by the Dirac equation so that charge carriers in graphene mimic relativistic particles with zero rest mass. Still, probably the most important “property” of graphene is that it has opened a floodgate of experiments on many other 2D atomic crystals: BN, NbSe2, TaS2, MoS22, etc. The resulting pool of 2D crystals is huge, and they cover a massive range of properties: from the most insulating to the most conductive, from the strongest to the softest. If 2D materials provide a large range of different properties, sandwich structures made up of 2, 3, 4 … different layers of such materials can offer even greater scope. Since these 2D-based heterostructures can be tailored with atomic precision and individual layers of very different character can be combined together, the properties of these structures can be tuned to study novel physical phenomena or to fit an enormous range of possible applications, with the functionality of heterostructure stacks is “embedded” in their design.
In 2014 Hewlett-Packard announced the development and commercialization of an innovative 3D printing technology that promised to set new standards for performance, quality, reliability and low TCO. HP's Multi Jet Fusion™ (MJF) technology achieves its breakthrough performance by leveraging the company's 30+ year history of innovation and market leadership in imaging and digital printing. This presentation will provide an introduction to a new-to-the-world digital fabrication technology that makes it possible to design and print three-dimensional objects that possess both precise geometric and functional characteristics. The MJF technology will radically change the way engineers and designers prototype and produce functional parts and the blending of HP's MJF 3D printing technology with digital materials design creates a new fabrication paradigm - a paradigm that enables innovation in both form and function.
Over recent years there has been tremendous progress in developing low-temperature processible organic and oxide semiconductors that can be processed by solution-based printing techniques and provide high charge carrier mobilities for both n-type and p-type field-effect transistor operation, good operational stability and other functionalities such as efficient electroluminescene, sensing or memory functions. In this talk I will discuss the basic device and charge transport physics of organic and oxide transistors, review manufacturing approaches and assess their performance in light of a range of applications in displays and integrated systems.
Technology Research Association for Future Additive Manufacturing (TRAFAM) was established in 2014 to achieve the development of innovative additive manufacturing systems to meet the world's highest standards and the development of manufacturing technologies for high value-added products. In this presentation, the current status of the TRAFAM project is introduced.
Within tissue engineering and regenerative medicine, Biofabrication is a young and dynamically evolving field of research [1]. It aims at the automated generation of hierarchical tissue-like structures from cells and materials through Bioprinting or Bioassembly. This approach has the potential to overcome a number of classical challenges relating to organization, personalized shape and mechanical integrity of generated constructs. Although this has allowed achieving some remarkable successes, it has recently become evident that the lack of variety in printable hydrogel systems is one major drawback for the complete field [2]. In order to be suitable for Biofabrication, hydrogels have to comply with a number of prerequisites with regards to rheological behavior and especially stabilization of the printed structure instantly after printing, while at the same time allowing the cells to proliferate. Also fabrication techniques are often not ideal and need to be optimized for the printing of anatomical structures. This lecture will briefly introduce the field and the major printing techniques, as well as the most important demands on materials and fabrication techniques. It will then introduce a new method for the rational design of thermoplast fibre constructs by the combination of melt electrospinning with automated movement of the collector (Melt electrospinning writing). This technique allows for the generation of highly regular fibrous constructs with pore sizes in cellular dimensions and fibre diameters down to submicrometer [3]. Printing of anatomical structures that would not be accessible otherwise will be demonstrated at one example. The lecture will then focus on printable hydrogels. Thiolene cross-linking of poly(glycidyl-co-allylglycidylether) based 3D plotted hydrogels will be introduced [4] as alternative to the often used free radical polymerization to stabilize printed hydrogel structures with high resolution and reproducibility. Furthermore, a purely physically cross-linked system based on recombinant spider silk proteins will be introduced [5], in which beta-sheet interactions facilitate good printability and stability of the constructs.
A new type of 3D printing process is introduced. The printing mechanism is based on material jetting process by inkjet-printing head to eject and deposit a photopolymer ink as the 3D object building material. The existing material jetting 3D printer adopted multi nozzle piezo-electrical print head. The piezo ink jet head requires complicated head structure, ink supply and maintenance system. The printing area should be large because of wide area of printing head and it causes that the 3D printing machine should be large and expensive for a commercial purpose only. In this study, Thermal ink jet head is applied to the print head for 3D printing process. The thermal head has low cost and compact printing mechanism but it is hard to apply photo polymer ink of material jetting process for jetting fluid because the thermal ink jet head fires the ink droplet by boiling mechanism. The specific building material for jetting in thermal head is applied and a 3D printing process is investigated for stable ejection and deposition on the substrate for building 3D object. The droplet volume of print head is under 20 pico-litters and ejection frequency is 2 kHz and the thickness of single layer deposited for building object is more than 10 micro-meters. The 3D printing system is fabricated and the hollow cylindrical object with high aspect ratio is successfully built and printing process is verified.
3D printer is expected to spread currently. This paper describes the processing method of modifying the FDM printed products. We get the characteristics of each of the processing by evaluation using the time and surface roughness.
We have developed the direct inkjet 3D fabrication system which can vary mechanical strength of nano-composite hydrogels on demand. The object body contains various parts which have gradual strength, colors and other physical properties. In addition, over-hanging and hollow structures were successfully obtained by using support material. It can be said that the hydrogel 3D fabrication system is able to construct a fine objects having partially controlled mechanical strength. Those objects have a potential of adding a unique value into the medical 3D model, and other applications. The methodology of hydrogel fabrication and the properties of the hydrogel object are discussed, and the blood vessel model and the hollow vascular model were prepared for surgical training application.
We report on two newly developed patterning methods for three-dimensional (3D) printed electronics applications, which are known as soft blanket gravure (SBG) and omnidirectional inkjet (OIJ) printing technologies. These technologies make it possible to print various inks directly onto non-flat or 3D object surfaces, and have a capability that could enable new electronic applications and markets.
The author is a co-author on a Wiley book under preparation entitled the “Handbook of Industrial Inkjet” (chief editor Werner Zapka). One area of relevant new content in this book is in surface manufacturing, which refers to the customization of a finished product — usually a manufactured good — by using printing and/or printing-like processes. Surface manufacturing is a form of additive manufacturing in which there is a template in the form of a partially finished object upon which to use as a surface for the (usually product-finishing) custom manufacturing. There are four major types of inkjetting that can be considered for a role in surface manufacturing. After describing these, we then consider their use in surface manufacturing in light of the Steady State Balance Macroscopic Mechanical Energy (SSMMEB) Equation. Some approaches to designing for variability are then discussed.