• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.874-877
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• 2000

Pre-coated sheet materials are a cost-effective and environmentally attractive alternative to conventional sheet materials coated after forming. At present but the high scratch sensitivity of coating used for pre-coated metal sheet is a major limitation to use of these materials. Because of high scratch sensitivity, products made by pre-coated metal sheet are not formed by conventional design method. This study has been performed to investigate scratch characteristic of non-vinyl pre-coated metal (PCM) sheet. Using the simple U-bending test equipment, three non-vinyls PCM's were tested. This paper provides the results of bending tests showing the influence of sheet surface texture, tool material and process conditions. It was found that the influence of punch, die clearance and tool material had an effect upon the scratch characteristic.

• Journal of Veterinary Clinics
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• v.11 no.1
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• pp.377-381
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• 1994

This study was performed to investigate the usefulness of the radiopaque material as a disintegration test of enteric coated capsules radiologically. The results obtained were as follows; 1. The times that the enteric coated capsules passed the pylorus(GI transition times) were the first 150 minute and the last 390 minutes. Therefore, the GI transition times largely differ from each animal and each enteric coated capsule. 2. The disintegration times of enteric coated capsules were similar in vitro test and in vitro test. 3. The disintegration test of enteric coated capsules using Barium sulfate, radiopaque material for the gastrointestinal track, was useful to check the time pass through the pylorus and the time enteric coated capsules were disintegration.

• Korean Journal of Veterinary Research
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• v.35 no.2
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• pp.391-398
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• 1995

This study was carried to investigate the usefulness of the radiopaque material as the GI transition and disintegration test of enteric coated capsules radiologically. The obtained results were as follows; 1. The GI transition times that the enteric coated capsules pass through the pylorus were that the time of the first capsule was 210 minutes and the time of the last capsules was more than 300 minutes. Therefore, the GI transition times largely differ from each animal and each enteric coated capsule. 2. The disintegration times of enteric coated capsules were similar in vitro test and in vivo test. 3. The GI transition and disintegration test of enteric coated capsules using barium sulfate, radiopaque material for the gastrointestinal track, was useful to investigate the times that the capsules passed through the pylorus and disintegrated in intestinal track.

• Journal of Pharmaceutical Investigation
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• v.5 no.4
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• pp.7-16
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• 1975

The drug release property from the coated tablets which contain 291mg of acetylsalicylic acid were estimated from comparison of the blood level and the urinary excretions after oral ingestion of coated tablets and noncoated tablet in human. The coating materials are 2-methyl-5-vinylpyridine-methylacrylic acid copolymer(MPM), dimethyl aminoethyl methacrylate methyl methacrylate copolymer(EE), polyvinyl acetal diethyl aminoacetate(AEA), and shellac. Each of 7 subjects ingested 873mg of acetylsaliylic acid. All tablets are coated approximately $3.5{\pm}0.5%(w/w)$ per tablet with each of the coating materials and met K.P.II. standard for potency and disintegration time. The availability was decreased in the following order:MPM coated tablets>EE coated tablets>AEA coated tablets>> shellac coated tablets.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.3
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• pp.63-72
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• 1998

This research was intended to evaluate the effect of carboxymethylcellulose(CMC) on the coating structure and surface strength of coated paper prepared with amphoteric latex based coating color. Printability and optical properties of coated papers were compared. The influence of the consolidation behavior of coating color on the coating structure and the surface strength of coated paper was investigated. Compared with the conventional anionic latex, amphoteric latex formed bulkyer, smoother and more porous coating layer, which in turn, restricted binder migration in the coating layers, and facilitated immobilization of coating colors. However, dry pick strength of coated paper was decreased. The addition of CMC to these systems had strongly influenced on. the consolidation behavior and porosity in the dry state, through forming the network structure of coating layers by the interaction with amphoteric latex particles. Thus, printability and optical properties of coated papers were improved. Results indicated that amphoteric latex could be practically applied to the paper coating to improve printability and optical properties of coated papers.

• Journal of the Korean Society of Clothing and Textiles
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• v.21 no.8
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• pp.1346-1352
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• 1997

The purpose of this study was to help the consumer as well as the producer by investigating the properties such as tensile strength, extention, tear strength, wrinkle recovery, drapability, bending property, moisture regain, and shrinkage on commercial polyurethane coated fabrics. Seven commercial polyurethane coated fabrics having various base fabrics were used. The performance properties of base fabrics and polyurethane coated fabrics were measured. The relationships between base fabrics and polyurethane coated fabrics on the performance properties were identified. It was concluded that the properties of polyurethane coated fabric mainly depend on the characteristics of base fabric. Therefore the proper use of base fabric is recommended in order to improve the performance of polyurethane coated fabric.

• Journal of the Korean institute of surface engineering
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• v.33 no.1
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• pp.17-24
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• 2000

The microstructures and corrosion properties of Al-Si diffusion coated PWA1426 and PWA658 alloys have been investigated. The coated layer and corrosion properties were analysed by SEM, EDS and hot corrosion test. According to the results of SEM, it is supposed that the coated layers were composed of mixed, denuded and inter-diffusion layer. The coated PWA1426 alloy improved corrosion properties, compared to the PWA658 alloy. Corrosion debris generated during hot corrosion test of PWA658 alloy are identified as NiO, $TiO_2$and $NiAl_2$$O_4$from coated layer which increase oxidation rate and decrease adhesion. The PWA1426 alloy heat treated at $1080^{\circ}C$ showed that NiAl and $Al_2$$O_3$formed on coated layer.

• Journal of the Korean Ceramic Society
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• v.32 no.12
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• pp.1401-1407
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• 1995

Zirconia powder coated with alumina was prepared by hydrolysis of alumina butoxide. The coated powder was obtained by a hydrolysis reaction between the adsorbed water on the surface of zirconia particles and aluminum sec-butoxide. Amorphous aluminum hydroxide was uniformly coated on the surface of zirconia particles with the thickness of about 30 nm. The shape and distribution of aluminum hydroxide was varied with an existence of surfactant. The coated layer of aluminum hydroxide consists of the fine particle size, and the zirconia powder coated by alumina hydroxide have the large specific surface area of 120 $m^2$/g, compared with that of starting zirconia powder.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.1121-1126
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• 2000

The purpose of this study is to clarify chemical resistance of polymer-cement slurry coated reinforcing bars. Polymer cement slurry coated reinforcing bars were showed the good state to the bending resistance, impact resistance, adhesive strength, but exact data of the chemical resistance do not exist. Through the experimental, it is to certify chemical resistance of polymer cement slurry coated reinforcing bars. In this study, polymer cement slurry coated reinforcing bars are prepared with two types of polymer, polymer-cement ratios of 50%, 100%, 150%, coating thickness, curing periods of 3, 7, 28days, and tested for chemical resistance as KS(Korea Standard). From the test results, chemical resistance of polymer cement slurry coated reinforcing bars used by acrylic and St/BA emulsion were showed excellent without concerned polymer-cement ratios, curing period except for 1% aqueous solution $H_2SO_4$. But polymer cement coated reinforcing bar used by acrylic emulsion is inferior to aqueous solution NaOH.

• YAKHAK HOEJI
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• v.39 no.6
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• pp.593-599
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• 1995

Erythromycin was formulated as enteric-coated pellets in order to reduce degradation in stomach and gastromtestmal irritation, and to maximize the absorption in intestine followmg its oral administration. Core pellets were prepared using fluid-bed granulator with two different methods (powder layering and solvent spraying) and enteric-coated with two different coating polymers (HPMCP and Eudragit E30D). Physical characteristics md dissolution rates of core pellets and enteric-coated pellets were evaluated to optimize the formulation. Powder layering method resulted in shorter initial dissolution time than solvent spraying method, but physicochmical properties of the product were worse than solvent spraying method with respect to hardness, ftiability and density. The dissolution rate of the drug was increased with the addition of surfactants, showing concentration-dependence. The scanning electron microscopic observation of pellets revealed significant differences on the surface appearances prepared with solvent spraying method. The core pellet made with powder layering method had crystals on the surface, which resulted in poor physical properties of the pellets. The dissolution profiles of erythromycin pellets coated with HPMCP or Eudragit L30D were close to that of commercially available erythromycin enteric-coated product.