Good jetting performance and pigment‐dispersing stability are necessary for pigment‐based ink‐jet inks. This study investigates how the chemical structures of the polymeric dispersants affect the pigment‐dispersing stability and jetting performance of ink‐jet inks. A series of polymeric dispersants containing styrene (hydrophobic unit) and acrylic acid (hydrophilic unit) with different ratios have been synthesized and used to disperse different pigments. Because 3000–12,000 ink drops can be expelled from the nozzle of a thermal bubble‐type ink‐jet printer within 1 s, the jetting behavior is related to the rheology variation of a dilute solution under a high shear. An in situ drop formation system has been used to study the high‐shear‐rate rheology (dynamic surface tension and dynamic viscosity) of a solution with a viscosity lower than 3 cps, which no commercial rheometer can measure. Excellent ink‐jet inks can only be produced by the combination of pigments, dispersants, and surfactants with appropriate hydrophilicity. Moreover, the correlation of the pigment surface properties, the chemical structures of the polymeric dispersants, and ink formulation is discussed. The effects of the surfactants and firing conditions on the jetting behavior of the ink‐jet ink are also examined. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1909–1920, 2003

ABSTRACT:The small-angle X-ray scattering technique was applied to study the morphology of a series of water-repellent terpolymers polymerized from a fluoro-component, a hydrocarbon-component and a crosslinking agent. The intraparticle homogeneity of the terpolymers was semiquantitatively determined from the small-angle X-ray spectra using a proposed structural model. The X-ray results were correlated to the water repellency test data using the AATCC test method . The consistency of the polymerization reaction process as a function of the weight ratio of the fluoro-components is discussed.

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3D Printing, also called Additive Manufacturing, has become a promising manufacturing method to produce parts in various fields as it can produce parts even with very irregular shapes in a relatively shorter process and time. However, during the printing process, some problems could decrease the accuracy and quality of the printed parts, such as warpage due to thermal strains, deformation due to inadequate supports, etc. The finite element method is most commonly adopted to evaluate engineering problems in advance to reduce possible failures; however, the element meshes, needed for analyses, are always irregularly distributed, especially for irregular objects, and cannot match the layer-by-layer growing shapes of the printed parts in the 3D printing process. Without a proper element mesh, the analysis cannot be performed. To overcome this problem, a layer-based mesh generator combined with a corresponding scheme for the 3D Printing simulation is proposed and developed. With the proposed methods, the analysis models can be designed and generated to match the growing shapes, i.e., layer-by-layer, and used to simulate the layer-by-layer growing behavior in the 3D printing process. Moreover, the proposed schemes directly adopt the Stereo-Lithography (STL) formatted geometric data as the geometry model on which the mesh generation and simulation are based. This makes them even easier to use since the STL geometry format is a De facto standard format used in the 3D printing industry. Several simulation cases have been conducted to demonstrate the effectiveness and efficiency of these proposed schemes.