• Title/Summary/Keyword: ink

Search Result 1,447, Processing Time 0.021 seconds

Polymer Inkjet Printing: Construction of Three-Dimensional Structures at Micro-Scale by Repeated Lamination

  • Yun, Yeon-Hee;Kim, Jae-Dong;Lee, Byung-Kook;Cho, Yong-Woo;Lee, Hee-Young
    • Macromolecular Research
    • /
    • v.17 no.3
    • /
    • pp.197-202
    • /
    • 2009
  • Solution-based, direct-write patterning by an automated, computer-controlled, inkjet technique is of particular interest in a wide variety of industrial fields. We report the construction of three-dimensional (3D), micro-patterned structures by polymer inkjet printing. A piezoelectric, drop-on-demand (DOD) inkjet printing system and a common polymer, PVA (poly(vinyl alcohol)), were explored for 3D construction. After a systematic preliminary study with different solvent systems, a mixture of water and DMSO was chosen as an appropriate solvent for PVA inks. The use of water as a single solvent resulted in frequent PVA clogging when the nozzles were undisturbed. Among the tested polymer ink compositions, the PVA inks in a water/DMSO mixture (4/1 v/v) with concentrations of 3 to 5 g/dL proved to be appropriate for piezoelectric DOD inkjet printing because they were well within the proper viscosity and surface tension range. When a dot was printed, the so-called 'coffee-ring effect' was significant, but its appearance was not prominent in line printing. The optimal polymer inkjet printing process was repeated slice after slice up to 200 times, which produced a well-defined, 3 D micro-patterned surface. The overall results implied that piezoelectric DOD polymer inkjet printing could be a powerful, solid-freeform, fabrication technology to create a controlled 3D architecture.

Development of a Portable and Disposable pH Sensor Based on Titanium Wire with High Electrochemical Sensing Performance (우수한 전기화학적 센싱 성능을 지닌 티타늄 와이어 기반의 휴대 및 일회용 pH 센서 개발)

  • Yoon, Eun Seop;Yoon, Jo Hee;Son, Seon Gyu;Kim, Seo Jin;Choi, Bong Gill
    • Applied Chemistry for Engineering
    • /
    • v.32 no.6
    • /
    • pp.700-705
    • /
    • 2021
  • A portable and disposable pH sensor based on Ti wire was successfully developed for monitoring hydronium ion concentrations. A sensing electrode was prepared by electrochemically depositing iridium oxide onto a Ti wire, while a reference electrode was fabricated by coating Ag/AgCl ink on a Ti wire. Combining the two electrodes in the pH sensor enabled the collection of open circuit potential signals when the sensor was immersed in solutions of various pH values. The pH sensor exhibited excellent electrochemical sensing performance in terms of sensitivity, response time, repeatability, selectivity, and stability. To demonstrate point-of-measurement applications, the pH sensor was integrated with a wireless electronic module that could communicate with a mobile application. The portable pH sensor accurately measured pH changes in real samples. The results obtained were consistent with those of using a commercial pH meter.

Analysis of Pest Prevention Packaging Cases in Preparation for Consumer Complaints Caused by Global Warming in the Product Distribution Process: Focusing on Poly Bag Packaging for Hygiene Products in Company A

  • Jung, Sung-Tae
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
    • /
    • v.27 no.1
    • /
    • pp.9-16
    • /
    • 2021
  • The present study was conducted to accomplish management efficiency by preparing preemptive measures for consumer dissatisfaction and overcome risks caused by Global Warming through studies of model cases in packaging. Through this study, we made it possible to find a way for companies to prepare for Global warming and consumer dissatisfaction. By contributing to eco-friendly packaging, we are trying to preemptively respond to recent major issues through packaging. Through this experiment, we tried to measure the degree of penetration of Plodia interpunctella H. larva into the insect repellent film produced by printing Ink containing a natural repellent. The control experiment was conducted with an untreated LDPE film to which no insect repellent was applied. The numbers decreased from 17 to 7 when the film was processed with repellent to show experimental results verifying effects of repellent by decrease in 10 (58.8% Decrease). Such results show that it is safe when the film is unfolded but in the case where the film is folded, the Plodia interpunctella H. punches through the film to lead to consumer dissatisfaction and it suggests that this can bring on risks to corporate management. Considering that most of the film is folded in the case of PE bag packaging, the direction which the corporations should take in terms of preparing for climate change countermeasures and consumer dissatisfaction has been clarified. Due to it receiving satisfactory results in safety rest results for printing film applied with pest repellent as well as the Quality analysis to test repellent contents of repellent film, it is certain that the importance of repellent method in packaging will increase in preparing for consumer dissatisfaction and actions against climate change henceforth.

A Study on Cepage of Syrah in France: focusing on Cote du Rhone Area (프랑스 와인품종 Syrah에 관한 연구: 북부 론 지역을 중심으로)

  • Ko, Jong Weon
    • International Area Studies Review
    • /
    • v.16 no.1
    • /
    • pp.379-405
    • /
    • 2012
  • It is France for the origin of wine cepage in the world. Cepage of Syrah is estimated as intense, aromatic and dense wine. It is getting popularized and enlarged in cultivation areas. Syrah is well planted cool areas and hot areas. It is high in alcohol degree concerning sugar content. Especially, this cepage is clear aroma and is the best well-aged wine. The strong points is deversed style, adapted to everywhere. Rhone is attracted public attention for strong and full-boied by international wine experts. Syrah is deep color like ink. From distincted aroma be formed to casis, meat, leather, burned rubber, brown suger, caramel, raisins bouquets by aging. It is popular among wine manias for strong characteristics, spycies, high tanin, lasting flavors. Nowadays it receive response in the world with powerful style and characreristics.

Study on the Status of Application of Trade Secrets in MSDS Provided in Workplaces (산업체 규모와 업종에 따른 MSDS 영업비밀 적용 실태조사 연구)

  • Lee, Kwon Seob;Choi, Heung Koo;Lee, In Seop
    • Journal of Korean Society of Occupational and Environmental Hygiene
    • /
    • v.29 no.1
    • /
    • pp.27-33
    • /
    • 2019
  • Objective: This study analyzed the status of the application of trade secrets in MSDSs according to size and type of industry. The contents of the MSDS non-public approval policy are summarized. We suggest proactive improvement requirements related to the operation of the MSDS non-public approval policy. Methods: To review this subject, we selected 153 manufacturers and six importers in such fields as organic chemical production. The trade secrets application status and ratio (%) of MSDSs by industry size and industry classification were investigated. Improvements toward a proactive system related to the operation of the MSDS non-public approval policy under the Occupational Safety and Health Act(OSHA) were summarized. Results and Conclusions: According to the results, the trade secret ratio in MSDSs by industry size was 33% in workplaces with less than 50 employees, 23.1% in workplaces with more than 50 but less than 100 workers, 73% in workplaces with more than 100 workers, and 83.4% in workplaces with 300 or more workers. For the trade secret writing rate for MSDSs by industry, the highest was MOCCP (Manufacture of ink, paint, coating and similar products) at 80.9%. MOC (Manufacture of other chemicals) was the lowest at 16.2%. We propose four proactive efforts to minimize the administrative burden of implementation of the MSDS non-public approval policy. The results of this study can be used as basic data for policy improvements to make more effective use of MSDS.

A Study on the Characteristic Expression of Korean Traditional Costumes shown in the Korean Paintings by Kim Hyun-Jung (김현정의 한국화에 나타난 한국 전통 복식의 표현 특성 연구)

  • Na, Yoo-Shin
    • Journal of Fashion Business
    • /
    • v.23 no.2
    • /
    • pp.124-139
    • /
    • 2019
  • The purpose of this study was to examine the characteristic expression of Korean traditional costumes shown in the Korean paintings by Kim Hyun-Jung. The study analyzed the paintings by Kim Hyun-Jung to find out the characteristics of the contemporary Korean paintings and the expression of Korean traditional costumes. The characteristics of Kim Hyun-Jung's works are as follows: 1) The paintings are drawn by using Korean traditional painting methods and finished with Korean traditional paper, hanji. Moreover, they show the Korean traditional costume as main subject material. 2) They use modern painting methods, such as collage, and show pop art characters by use of contemporary popular products. 3) The artist communicates with the public through SNS and YouTube, and shows characteristics of popular art through commercial art products and advertisements. The characteristics of the Korean traditional costume in Kim Hyun-Jung's works are as follows. 1) The hanbok shown in the paintings is a traditional style with tight jeogori and wide chima. Chima is drawn in thin coloring with Korean ink and jeogori is expressed with semi-transparent hanji in various patterns and colors, which shows the subject 'coy'. 2) Various kinds of Korean traditional accessories and modernized flower shoes with high heels are shown as subject materials. The art works by contemporary Korean artists are expected to be the route to give valuable information to the public about Korean traditional costumes as well as the trendy Korean culture.

[Retraction]Characterization of carbon black nanoparticles using asymmetrical flow field-flow fractionation (AsFlFFF)

  • Kim, Kihyun;Lee, Seungho;Kim, Woonjung
    • Analytical Science and Technology
    • /
    • v.32 no.3
    • /
    • pp.77-87
    • /
    • 2019
  • High viscosity carbon black dispersions are used in various industrial fields such as color cosmetics, rubber, tire, plastic and color filter ink. However, carbon black particles are unstable to heat due to inherent characteristics, and it is very difficult to keep the quality of the product constant due to agglomeration of particles. In general, particle size analysis is performed by dynamic light scattering (DLS) during the dispersion process in order to select the optimum dispersant in the carbon black dispersion process. However, the existing low viscosity analysis provides reproducible particle distribution analysis results, but it is difficult to select the optimum dispersant because it is difficult to analyze the reproducible particle distribution at high viscosity. In this study, dynamic light scattering (DLS) and asymmetrical flow field-flow fractionation (AsFlFFF) analysis methods were compared for reproducible particle size analysis of high viscosity carbon black. First, the stability of carbon black dispersion was investigated by particle size analysis by DLS and AsFlFFF according to milling time, and the validity of analytical method for the selection of the optimum dispersant useful for carbon black dispersion was confirmed. The correlation between color and particle size of particles in high viscosity carbon black dispersion was investigated by using colorimeter. The particle size distribution from AsFlFFF was consistent with the colorimetric results. As a result, the correlation between AsFlFFF and colorimetric results confirmed the possibility of a strong analytical method for determining the appropriate dispersant and milling time in high viscosity carbon black dispersions. In addition, for nanoparticles with relatively broad particle size distributions such as carbon black, AsFlFFF has been found to provide a more accurate particle size distribution than DLS. This is because AsFlFFF, unlike DLS, can analyze each fraction by separating particles by size.

Fabrication of Potentiometric Sodium-ion Sensor Based on Carbon and Silver Inks and its Electrochemical Characteristics (탄소 및 은 잉크 기반의 전위차 나트륨 이온 센서 제조 및 이의 전기화학적 특성)

  • Kim, Seo Jin;Son, Seon Gyu;Yoon, Jo Hee;Choi, Bong Gill
    • Applied Chemistry for Engineering
    • /
    • v.32 no.4
    • /
    • pp.456-460
    • /
    • 2021
  • A potentiometric sodium-ion (Na+) sensor was prepared using a screen-printing process with carbon and silver inks. The two-electrode configuration of the sensor resulted in potential differences in Na+ solutions according to Nernstian equation. The obtained Na+-sensor exhibited an ideal Nernstian sensitivity, fast response time, and low limit of detection. The Nernstian response was stable when the sensor was tested for repeatability and long-term durability. The Na+-selective membrane coated onto the carbon electrode selectively passed sodium ions against interfering ions, indicating an excellent selectivity. The portable Na+-sensor was finally fabricated using a printed circuit system, demonstrating the successful measurements of Na+ concentrations in various real samples.

A review of 3D printing technology for piezoresistive strain/loadcell sensors (3D 프린팅 센서 연구 동향 소개-전왜성 변형/로드셀 센서 중심으로)

  • Cho, Jeong Hun;Moon, Raymond Hyun Woo;Kim, Sung Yong;Choi, Baek Gyu;Oh, Gwang Won;Joung, Kwan Young;Kang, In Pil
    • Journal of Sensor Science and Technology
    • /
    • v.30 no.6
    • /
    • pp.388-394
    • /
    • 2021
  • The conventional microelectromechanical system (MEMS) process has been used to fabricate sensors with high costs and high-volume productions. Emerging 3D printing can utilize various materials and quickly fabricate a product using low-cost equipment rather than traditional manufacturing processes. 3D printing also can produce the sensor using various materials and design its sensing structure with freely optimized shapes. Hence, 3D printing is expected to be a new technology that can produce sensors on-site and respond to on-demand demand by combining it with open platform technology. Therefore, this paper reviews three standard 3D printing technologies, such as Fused Deposition Modeling (FDM), Direct Ink Writing (DIW), and Digital Light Processing (DLP), which can apply to the sensor fabrication process. The review focuses on strain/load sensors having both sensing material features and structural features as well. NCPC (Nano Carbon Piezoresistive Composite) is also introduced as a promising 3D material due to its favorable sensing characteristics.

Ag Nanoparticle Self-Generation and Agglomeration via Laser-Induced Plasmonic Annealing for Metal Mesh-Based Transparent Wearable Heater (레이저 기반 플라즈모닉 어닐링을 통한 은 나노입자 자가 생성 및 소결 공정과 이를 활용한 메탈메쉬 전극 기반 투명 웨어러블 히터)

  • Hwang, Yun Sik;Nam, Ui Yeon;Kim, Yeon Uk;Woo, Yu Mi;Heo, Jae Chan;Park, Jung Hwan
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.35 no.5
    • /
    • pp.439-444
    • /
    • 2022
  • Laser-induced plasmonic sintering of metal nanoparticles (NPs) is a promising technology to fabricate flexible conducting electrodes, since it provides instantaneous, simple, and scalable manufacturing strategies without requiring costly facilities and complex processes. However, the metal NPs are quite expensive because complicated synthesis procedures are needed to achieve long-term reliability with regard to chemical deterioration and NP aggregation. Herein, we report laser-induced Ag NP self-generation and sequential sintering process based on low-cost Ag organometallic material for demonstrating high-quality microelectrodes. Upon the irradiation of laser with 532 nm wavelength, pre-baked Ag organometallic film coated on a transparent polyimide substrate was transformed into a high-performance Ag conductor (resistivity of 2.2 × 10-4 Ω·cm). To verify the practical usefulness of the technology, we successfully demonstrated a wearable transparent heater by using Ag-mesh transparent electrodes, which exhibited a high transmittance of 80% and low sheet resistance of 7 Ω/square.