Papers by Keyword: Screen Printing

Abstract: This study was performed to investigate comfort properties and antimicrobial activity of cotton and nylon knits treated with microcapsules containing sea buckthorn fruit oil reported as having antimicrobial efficacy depending on concentration of microcapsules and treatment types. Chitosan-arabic gum microcapsules containing sea buckthorn fruit oil were prepared and they were treated on cotton and nylon/PU knit respectively by an experimental design of 2 different treatment types (bath immersion method and screen printing method) Χ 5 different concentration levels of microcapsules (20, 30, 40, 50, and 60% on the weight of fabric). As comfort properties, stiffness, water-vapor permeability, and air permeability were measured objectively. Antimicrobial activity was evaluated by calculating the percentage reduction of the bacterium. As results, stiffness values of the treated knits were slightly higher than those of untreated ones, which was thought not to affect touch in wear. The values of water-vapor permeability and air permeability of both cotton and nylon after the treatment were not significantly decreased. These results means that microcapsules loaded on the knits might not worsen their wear comfort. As for antimicrobial activity, more than 90% of bacterial reduction rates against S. Aureus were shown in cotton jersey by screen printing even after repeated laundry while those was found in nylon/PU tricot by bath immersion. From these results, it was concluded that chitosan-arabic gum microcapsule containing sea buckthorn fruit oil could be utilized for textiles to provide antimicrobial activity.

Abstract: Smart packaging becomes more popular as it increases the safety of food consumption by monitoring a packaged food state and informing the customer about it, for example, by visual reaction of a special label on its surface. Nanomaterials can provide the needed functionality to such labels. Application of ink compositions containing silver nanoparticles on paper materials by screen printing is quite promising. A special ink composition was developed based on Ag nanoparticles that possess changeable photoluminescence properties in contact with compounds that indicate food decay. The possibility of application of this ink onto the surface of paper-based materials via screen printing was studied. The influence of ink layer thickness, characteristics of paper materials (degree of sizing, content of optical brighteners), and content of the fluorescent component in the ink composition on photoluminescence properties of printed labels for smart packaging was investigated. It was determined how to choose proper values of these technological parameters in order to obtain high luminescence intensity and predetermined luminescence color of printed labels using the developed nanophotonic inks. The results of the study allow industrial production of functional labels for smart packaging with nanophotonic elements with the needed optical (photoluminescence) characteristics, as well as for protecting packaging from counterfeiting.

Abstract: In this work, the optimal sintering temperature and time of commercial copper paste were tested experimentally. The electrical properties of conductive paste including square resistance and resistivity were characterized and analyzed. The influence of diatomite with different purification processes on the electrical properties of commercial copper paste was analyzed. The performance of copper slurry modified by copper-based modified diatomite prepared by two-step reduction method was analyzed. The optimum square resistance and resistivity was obtained with copper paste doped by 0.25wt.% and 1 h-ball milled diatomite and was 0.02Ω/_ϒ and 0.011Ω·mm, respectively.

Abstract: In this paper, the design and fabrication of a liquid conductivity sensor based on AgPd paste will be described. The device was designed in a four-electrode configuration on a 10 x 25 mm² 96% Al₂O₃ substrate. The distance between the two driving electrodes was 4 mm, whereas the distance between the two measuring electrodes was 2 mm.The device was also integrated with a Ruthenium based temperature sensor printed on the backside of the substrate. Initial characterisation showed that the conductivity sensor has a measured sensitivity and cell constant of 1.67 cm and 0.51 cm^-1, respectively, when a frequency of 1 kHz square wave input was appliedto the driving electrodes. Sensor’s respond variation against temperature was measured around 27.89 μS/°C, corresponding to 2.22 temperature compensation value for salt solution. The results showed a stable response over 5 days measurement cycle, indicating the sensor’s potential for field water quality monitoring application.

Abstract: A non-aqueous synthesis technique of room temperature curable titania ink, screen printed on flexible BoPET film for printed electronics applications is reported. The phase evolution of rutile titania powder, formulation of a fast curing titania ink, as well as the microstructure and dielectric properties of printed pattern are discussed. In terms of ease of synthesis, cost effectiveness and faster curing time, the developed ink is found to be advantageous over water based dielectric inks.

Abstract: Color glasses are fabricated with Titanium target by RF magnetron sputtering. The physical properties of the Ti thin films are investigated according to preparation conditions, such as argon and oxygen gas flow ratio, RF power and Working pressure. The results indicate that it is possible to deposits various Ti thin film’s of different colors on glass substrate, such as yellow, orange, brown, purple. The thickness according to the color was analyzed using Veeco's Stylus profiler (model: dektak 6M).

Abstract: The high-k composite dielectric ink is prepared by dispersing the surface modified BaTiO3 in PMMA solution. The high quality BaTiO₃-PMMA composite films are screen printed on ITO glasses. BaTiO₃ nanoparticles are surface modified with a silane coupling agent (MPTMS) to improve their affinity for PMMA matrix. The dielectric constant, loss tangent, specific capacitance and transmittance of BaTiO₃/PMMA nanocomposites are investigated as the function of volume fraction of BaTiO₃. These composites, which possess both high dielectric constant and low dissipation factors and can be screen printed at ambient temperature and pressures, have very wide practical applications.

Abstract: In order to obtain high quality ultrathin free-standing ceramic chips, a new manufacturing process based on the screen printing and the cold isostatic pressing process has been developed. ¹⁾ In this process, an ultrathin free-standing green sheet (less than 20 μm thick) can be achieved successfully as shown in Fig. 1. After sintering, an ultrathin free-standing ceramic chip (less than 20 μm thick) with good density uniformity, can be obtained as shown in Fig. 2. In addition, the thicknesses of the ultrathin chips can be adjusted by changing the printing parameters for different application requirements. Such process can significantly widen the scope and applicability of the ultrathin chips in many kinds of materials.

Abstract: Because of good and fine printing quality, screen printing is very common technology in printing and dyeing factory recently. Developing is important to insure the screen printing quality. In this paper, a developer structure is designed and studied. Fluent software is used to analyze the developing process. In this way, the numerical model of nozzle is founded. The jet flow fields of different structure fan-type nozzles are analyzed and compared. Depended on the simulation results, the right nozzle is chosen and used in the developer structure, and the structure of developer is modified to fit the cleaning quality required. The experiment of new structure developer with the chosen nozzle is done, and the experiment result shows better cleaning quality with the new developer and new nozzle.

Abstract: This paper studied in the process of RFID screen printing, the influence of mesh number, curing temperature and curing time on the RFID tag resistance. During the experiment, there are three specifications, 120 meshes, 250 meshes, 350 meshes , the curing temperature is set as 110 °C, 120 °C, 140 °C, 150 °C, 160 °C and the curing time is 5min, 10min, 15min, 20min, 25min. The experimental results indicate that RFID tags produced by the screen of 120 meshes have rough surface and fail to meet the requirements; when the curing temperature and curing time respectively reaches 150 °C and 20min, the resistance value of the antenna is low and stable.