• Journal of the Korean Wood Science and Technology
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• 제50권3호
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• pp.149-158
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• 2022

To realize the infinite possibilities of materials derived from wood, it is necessary to overcome the weak moisture stability of wood. Thus, the development of an eco-friendly hydrophobic coating agent is essential, and of these, woody biomass-based materials are strongly attractive as coatings. In this study, eco-friendly hydrophobic wood coatings were prepared using carnauba wax purified from palm leaves and sprouts, and kraft lignin. The physicochemical properties of the carnauba wax/lignin blends according to the ratio of carnauba wax and lignin were observed by morphology and functional group change. In addition, the coating performance of carnauba wax/lignin blend coatings was confirmed by measuring the contact angle change. It was found that the addition of lignin could accelerate the atomization of wax particles, and that micro-roughness can be realized when applied to the actual wood surface, to ensure that the coating effect over time lasts longer. In addition, it was confirmed that the addition of lignin increases the hydrogen-bond-based interaction with the wood of the coating, thereby providing better coating stability and increasing the durability of the coating solvent under friction. The carnauba wax/lignin paint developed in this way is eco-friendly because all components are made of wood-based raw materials and have an excellent affinity with wood surfaces. Therefore, it is expected to be applicable to the coating process of wood-plastic composites and timber composites.

• 펄프종이기술
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• 제41권2호
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• pp.64-69
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• 2009

Cultural heritages represent the histories and intellectual level of a country. The Annals of Joseon Dynasty are regarded as the most valuable resources containing the record of Korean history. In some periods, wax-treated paper was used as the material of the Annals of Joseon Dynasty. Many previous studies have focused on the development of paper used as the material of the Annals of Joseon Dynasty, but the manufacture method of wax-treated volumes and the degradation mechanism of wax have been not fully understood yet. The purposes of the present study are to produce various kinds of wax-treated paper using by different coating methods and to analyse the morphological properties of wax-treated paper. The analysis of SEM demonstrates that beeswax treated paper made by brushing method produces flatter surface and more excellent penetration. Wax layer is produced on the cross section of beeswax treated paper as the increase of coating amount.

• Journal of Advanced Marine Engineering and Technology
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• 제38권10호
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• pp.1333-1339
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• 2014

As the demand for petroleum resources increases, and oilfields on lands and in shallow-sea become exhausted, the areas for oil production are expanding to the deep sea and therefore technologies for flow assurance are coming into the highlight. In low temperature environment such as the deep sea, wax is accumulated and prevents stable oil production. Therefore, the development of flow assurance technologies is required. Wax is precipitated in crystalline form when the oil temperature decreases below the wax appearance temperature; it then accumulates on the inner walls of pipelines causing blockages. In particular, in subsea pipelines, which have a large surface contact area with the surrounding seawater, wax deposition problems are frequent. The internal tubular coating can effectively reduce wax deposition without pausing oil production when the coating is appropriately designed. This study carried out wax deposition tests on a number of internal tubular coatings under single flow conditions. The results were analyzed for the effects that the physical properties of the coatings had on wax deposition.

• KSBB Journal
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• 제27권5호
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• pp.319-323
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• 2012

Vitamin C or L-ascorbic acid, an essential nutrient for humans with antioxidative property, was coated with natural wax to be used as functional additives for cosmetics. Coating of vitamin C was performed using carnauba wax and olive wax in self-designed reaction chamber for 60 min. The yield of coated vitamin C with carnawuba wax and olive wax were up to $94.6{\pm}1.2%$ and $82.5{\pm}1.4%$, respectively. The stability of the carnauba wax-coated vitamin C in the lotion was improved 17.8% than that of uncoated vitamin C during 30 day storage at $25^{\circ}C$. Color and the layer separation of the lotion added with the coated vitamin C showed better property than with the uncoated vitamin C. The coated vitamin C can be applied to cosmetic ingredients as a stable additive.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.659-662
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• 2002

SL(Stereolithography) part is made by piling up thin layers which causes the stair stepping effect at the surface of SL parts. This effect brings about excessive surface roughness and requires additional post-process finishing such as abrasive techniques that are detrimental to part geometry and time consuming. Hence a wax coating and grinding post-process is proposed to improve the surface quality of SL part. The wax that has suitable properties for the proposed post-process is coated all over the part surface. By grinding the thin layer of coated on the SL part only, the surface roughness can be improved without any damage on the part. From the experimental results, This approach is considered to be very practical fur die casting with RT(Rapid Tooling) techniques.

• 한국생산제조학회지
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• 제22권3_1spc호
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• pp.531-536
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• 2013

An automatic wax-ring manufacturing system for silk coating was developed, which consisted of a container, pallet with a cooling part, injection port, and removing device. The removing device is a system to load, lift, and cut the wax-ring, which is widelyused for various silk-coating industrial purposes. A novel removing device equipped with a water cooling circulation system is proposed in this paper. It has the benefit of easy control, as well as the convenience of loading and unloading without the use of other equipment. Three-dimensional modeling techniques were adopted to develop integrated functions for the automatic wax-ring manufacturing system, which made it possible to confirm the smooth integration/interface of each part and the system's interrelations with other manufacturing systems.

• 한국기계가공학회지
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• 제14권3호
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• pp.105-111
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• 2015

Ultrasonic machining (USM) does not involve heating or any electrochemical effects, and subsequently causes low surface damage, has small residual stress, and does not rely on the conductivity of the workpiece. These characteristics are suitable for the machining of brittle materials, such as glass or ceramics. However, USM for brittle materials generates cracks on the workpiece while machining, especially at the hole exit with a small diameter. In this study, wax coating was used to deposit wax on the back side of the workpiece to decrease the occurrence of cracks at the exit holes in USM, and it was finally removed with a cleaning process. The experimental results show that this technique is beneficial for restricting the occurrence of cracks in glass or ceramics.

• 한국기계가공학회지
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• 제10권6호
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• pp.146-151
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• 2011

Wax spin coating is a part of several wafer handling processes in the silicon wafer polishing station. It is important to ensure the wax layer free of contamination to achieve the high degree of planarization on wafers after wafer polishing. Three-dimensional air flow characteristics in a wax spin coater are numerically investigated using computational fluid dynamics techniques. When the bottom of the wax spin coater is closed, there exists a significant recirculation zone over the rotating ceramic block. This recirculation zone can be the source of wax layer contamination at any rotational speed and should be avoided to maintain high wafer polishing quality. Thus, four air suction ducts are installed at the bottom of the wax spin coater in order to control the air flow pattern over the ceramic block. Present computational results show that the air suction from the bottom is quite an effective method to remove or minimize the recirculation zone over the ceramic block and the wax coating layer.

• 보존과학회지
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• 제33권2호
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• pp.121-130
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• 2017

현재 야외 철제 조형물 보존용 코팅제로 사용되고 있는 wax는 장점도 있지만 낮은 내구성 및 안정성 등의 단점으로 인한 사용상의 문제점이 노출되고 있다. 손상원인으로는 대기오염에 의한 대기가스와 산성비, 공기 중의 수분, 미세먼지, 황사 등에 의해 wax가 노화되어 코팅력이 저하되고, 이로 인해 보존처리 후 짧은 시간 내에 재 부식이 발생한다. 또한 wax의 노화로 색상변화 및 광택변화가 일어나 표면 이질감을 주기도 한다. 이러한 문제점들은 장기간 지속되어 왔으며 이를 개선하기 위한 재료의 개발이 필요한 실정이다. 이에 본 연구에서는 기존에 사용되어지고 있는 wax 코팅제들을 분석하여 각각의 특성과 용도별로 부족한 점들을 파악하여 보다 개선된 wax 코팅제를 개발하였으며, 야외 폭로실험과 인공 산성비 실험을 통해 환경 변화에 따른 표면 코팅 변화양상을 확인해본 결과 기존 재료들 보다 야외 폭로실험결과 약 4배, 인공 산성비 실험 결과 약 1.5배 이상의 우수한 부식방지 및 차단 효과를 나타내었다. 또한 색도 및 광택도, 접촉각, 박막두께 등의 물성 측정을 통해 기존에 사용되어온 wax보다 박막두께는 약 1.3 ~ 1.8배 두껍지만 고른 피막을 형성해 외부 환경으로 부터의 차단성 및 내구성이 우수하고 색도 및 광택도도 기존의 재료와 유사한 물성을 보여주어 기존에 사용되어온 wax 코팅제를 대체할 수 있는 재료로 판단된다.

• 한국식품저장유통학회지
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• 제5권2호
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• pp.138-143
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• 1998

The stowage effects of Satsuma mandarin(Citrus unshiu Marc. var. miyagawa) were investigated by selecting various pretreatmnents; non-tested, wax-coating, paper packaging, 0.02mm cryovac film packaging. Weight loss of film packaging was the lowest among that of others, but decay radio was increased highly at late stages of storage. Soluble solids, moisture content of peel and total sugar were maintained almost constant, but acid content, vitamin C and firmness were reduced gradually during storage at room temperature. For 100 days storage, losses from weight and decay of ton-treated, paper packaging, wax-coating and film packaging were 15.9%, 18.5%, 17.4% and 12.9%, respectively. Acid content was decreased loom 1.28% to 0.81∼0.91% after 100 days storage. Ethylene evolution was increased in a degree after 65 days storage, and the amount was increased repidly afer 115 days. it seemed to be derived from decayed fruits and physiological activities. CO2 content of inner part of fruits was increased between 40∼100 days after storage. Optimum storage period of early variety of Satuma mandarin was regarded for 100days on the basis of appeareance and taste.