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Printing Technique (printing + technique)
Selected AbstractsA polymeric master replication technology for mass fabrication of poly(dimethylsiloxane) microfluidic devicesELECTROPHORESIS, Issue 9 2005Hai-Fang Li Abstract A protocol of producing multiple polymeric masters from an original glass master mold has been developed, which enables the production of multiple poly(dimethylsiloxane) (PDMS)-based microfluidic devices in a low-cost and efficient manner. Standard wet-etching techniques were used to fabricate an original glass master with negative features, from which more than 50 polymethylmethacrylate (PMMA) positive replica masters were rapidly created using the thermal printing technique. The time to replicate each PMMA master was as short as 20 min. The PMMA replica masters have excellent structural features and could be used to cast PDMS devices for many times. An integration geometry designed for laser-induced fluorescence (LIF) detection, which contains normal deep microfluidic channels and a much deeper optical fiber channel, was successfully transferred into PDMS devices. The positive relief on seven PMMA replica masters is replicated with regard to the negative original glass master, with a depth average variation of 0.89% for 26 ,m deep microfluidic channels and 1.16% for the 90 ,m deep fiber channel. The imprinted positive relief in PMMA from master-to-master is reproducible with relative standard deviations (RSDs) of 1.06% for the maximum width and 0.46% for depth in terms of the separation channel. The PDMS devices fabricated from the PMMA replica masters were characterized and applied to the separation of a fluorescein isothiocyanate (FITC)-labeled epinephrine sample. [source] High Definition Digital Fabrication of Active Organic Devices by Molecular Jet Printing,ADVANCED FUNCTIONAL MATERIALS, Issue 15 2007J. Chen Abstract We introduce a high resolution molecular jet (MoJet) printing technique for vacuum deposition of evaporated thin films and apply it to fabrication of 30,,m pixelated (800,ppi) molecular organic light emitting devices (OLEDs) based on aluminum tris(8-hydroxyquinoline) (Alq3) and fabrication of narrow channel (15,,m) organic field effect transistors (OFETs) with pentacene channel and silver contacts. Patterned printing of both organic and metal films is demonstrated, with the operating properties of MoJet-printed OLEDs and OFETs shown to be comparable to the performance of devices fabricated by conventional evaporative deposition through a metal stencil. We show that the MoJet printing technique is reconfigurable for digital fabrication of arbitrary patterns with multiple material sets and high print accuracy (of better than 5,,m), and scalable to fabrication on large area substrates. Analogous to the concept of "drop-on-demand" in Inkjet printing technology, MoJet printing is a "flux-on-demand" process and we show it capable of fabricating multi-layer stacked film structures, as needed for engineered organic devices. [source] Fabrication and Tunable Dielectric Properties of (Ba0.7Sr0.3)TiO3 -Glass-Based Thick-Film CapacitorsINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 2 2009Pulipparambil Vasu Divya Ferroelectric glass,ceramics of composition 0.90 (Ba0.7Sr0.3) TiO3,0.10(B2O3:SiO2) (0.90 BST:0.10 BS) synthesized by sol,gel method have been used for the preparation of dielectric thick-film inks. The particle dispersion of the glass,ceramic powders in the thick-film ink formulations have been studied through rheological measurements for fabricating thick-film capacitors by screen printing technique. The thick films derived from such glass,ceramics are found to sinter at considerably lower temperatures than the pure ceramic, and exhibit good dielectric characteristics with a tunability of 32% at 1 MHz under a dc bias field of 35 kV/cm. [source] Novel 3D collagen scaffolds fabricated by indirect printing technique for tissue engineeringJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2008C. Z. Liu Abstract This article reports the mechanical properties and in vitro evaluation of a collagen scaffold fabricated using an indirect 3D printing technique. Collagen scaffolds, featuring predefined internal channels and capillary networks, were manufactured using phase change printing. It was observed that the collagen scaffolds featured internal channels and a hierarchical structure that varied over length scales of 10,400 ,m. In vitro evaluation using hMSCs demonstrated that the resultant collagen based scaffolds have the ability to support hMSC cell attachment and proliferation; cells can migrate and survive deep within the structure of the scaffold. The cell numbers increased 2.4 times over 28 days in culture for the lysine treated scaffolds. The cells were spread along the collagen fibers to form a 3D structure and extracellular matrix was detected on the surface of the scaffolds after 4 weeks in culture. The crosslinking treatment enhanced the biostability and dynamic properties of the collagen scaffolds significantly. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008 [source] Transformation of 3DP gypsum model to HA by treating in ammonium phosphate solutionJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2007Rungnapa Lowmunkong Abstract Three-dimensional printing (3DP) is a CAD/CAM built-up using ink-jet printing technique. Commercially available 3DP system can form only gypsum model and not for bioceramics. On the other hand, transformation of hardened gypsum into hydroxyapatite (HA) by treatment in ammonium phosphate solution was found lately. In the present study, transformation of the 3DP gypsum block to HA was attempted. However, the fabricated 3DP block was soluble in water. To insolubilize, it was heated at 300°C for 10 min, and then, gypsum was transformed to calcium sulfate hemihydrate, CaSO4 · 0.5H2O. The 3D block was immersed in 1M (NH4)3PO4 · 3H2O solution at 80°C for 1,24 h, and the transformation into HA within 4 h was ascertained. A heat-treated plaster of Paris (POP) block was also investigated for comparison. The unheated POP block consisting of gypsum dihydrate took 24 h to complete the transformation, while the heat-treated POP consisting calcium sulfate hemihydrate promoted the transformation into HA; but the transformed thickness in the block was less than the 3DP block. This is probably due to higher solubility of the hemihydrate than gypsum dihydrate. Accelerated transformation of the 3DP block was also caused by its porous structure, which enabled an easy penetration of the phosphate solution. With the present method, it is possible to transform the fabricated gypsum by 3D printing that is adaptive to the osseous defect into HA prostheses or scaffold. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007 [source] Polymer-Based Rectifying Diodes on a Glass Substrate Fabricated by Ink-Jet PrintingMACROMOLECULAR RAPID COMMUNICATIONS, Issue 4 2005Yi Liu Abstract Summary: The fabrication of polymer diodes on a glass substrate by an ink-jet printing technique is reported. Both an n-type semiconductive polymer, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-(1-cyanovinylene)phenylene] (CN-PPV), and a p-type semiconductive polymer, polypyrrole (PPy) or poly(3,4-ethylenedioxythiophene) (PEDOT), were printed through a piezoelectric ink-jet printer. The printed CN-PPV/PPy and CN-PPV/PEDOT diodes showed good rectifying characteristics. These results indicate the potential of the low-cost ink-jet printing technique to produce polymer microelectronic devices and circuits. Schematic diagram of the printed polymer diode [source] | ||||||||||