• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4329-4335
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• 2014

This study examined the effects of the shear bond strength when the surface condition of the metal and zirconia, each being the lower structures, was different when determining the bond strength (metal group) of the metal lower structure with upper ceramics, and the shear bond strength (zirconia group) of zirconia lower structure with the upper ceramics in prosthetic appliances of metal-ceramic crown and zirconia-ceramic crowns. The metal groups were divided into a total of four groups: the group with no condition on the metal surface(NM), the group with sand-blasting(SM), the group with applied opaque ceramics(OM), and the group with applied opaque ceramics and sand-blasting(SOM). The zirconia groups were also separated into four groups: the group with no condition(NZ), the group with sand-blasting(SZ), the group treated with ZirLiner on the zirconia surface(LZ), and the group applied with ZirLiner along and sand-blasting(SLZ). To examine the effects on the shear bond strength according to the surface condition of each of the four metal and zirconia groups, SPSS was used to conduct one-way ANOVA. For metal-ceramic crowns, it would be best to apply opaque ceramics after sand-blasting on the surface of the metal, the lower structure. For zirconia-ceramic crowns, it is recommended to apply the ZirLiner after sand-blasting on the surface of zirconia, the lower structure.

• Journal of Technologic Dentistry
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• v.43 no.2
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• pp.70-70
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• 2021

• Journal of Technologic Dentistry
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• v.37 no.3
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• pp.121-127
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• 2015

Purpose: This study was intended to investigate the effect of applying liner for chemical bonding and physical surface roughness created on zirconia by using a sandpaper before sintering on the bond strength between the two materials. Methods: Zirconia blocks were cut using a low-speed cutter. Plate-shaped specimen($6mm{\times}6mm{\times}3mm$) was fabricated by sintering after giving surface roughness according to four kinds of sandpapers. Depending on whether or not to use liner, 60 specimens were divided into two groups ZN(non-liner), ZL(liner), and the two groups were subdivided into four groups respectively in accordance with sandpaper used, totaling eight groups (n=10). The surface roughness (Ra) values and shapes before sintering were observed, and shear bond strength after pressing ceramic plasticity was measured with a universal testing machine. For a test of the significance, a one-way ANOVA was performed, and Tukey's multiple comparison test was conducted. Results: The observation of the surface roughness was SB04($2.22{\pm}1.16{\mu}m$), SB08($2.98{\pm}0.33{\mu}m$), SB12($2.44{\pm}1.32{\mu}m$), SB20($2.34{\pm}0.59{\mu}m$) and SA04($2.34{\pm}0.67{\mu}m$), SA08($1.28{\pm}0.90{\mu}m$), SA12($2.03{\pm}1.60{\mu}m$), SA20($2.19{\pm}1.73{\mu}m$). In the case of ZN Group, the shear bond strength was ZN04($23.26{\pm}3.83MPa$), ZN08($21.76{\pm}2.33MPa$), ZN12($20.49{\pm}3.01MPa$), ZN20($24.98{\pm}4.22MPa$)(p<0.05). As for ZL Group, the shear bond strength was ZL04($25.09{\pm}5.67MPa$), ZL08($22.98{\pm}2.26MPa$), ZL12($21.54{\pm}5.70MPa$), ZL20($23.98{\pm}3.23MPa$)(p<0.05). Conclusion: The research results showed that the bond strength of Zirconia core and Pressing ceramic was further improved by physical surface treatment before sintering, rather than by chemical bonding through liner surface treatment.

• Food Science and Preservation
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• v.24 no.7
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• pp.898-907
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• 2017

This study was aimed to test harvest time effect with polyethylene (PE) film liner, 1-methylcyclopropene (1-MCP) and aminoethoxyvinylglycine (AVG) treatments on fruit quality attributes in 'Sangjudungsi' persimmon fruit during cold storage. The fruits were harvested 10 days earlier in 2016 than the mature harvest time in 2015. The ethylene production was significantly lower in early harvested fruits than in mature harvested ones. Flesh firmness was maintained higher in 1-MCP treated fruit than in other treatments during cold storage. The rate of fruit weight loss was significantly inhibited by PE film liner treatment during storage, regardless of harvest time. 1-MCP treatment showed less change in fruit peel color variables ($L^*$ and $b^*$) from the calyx-end and equatorial regions during cold storage, compared with those from the control and PE film treatments. The incidence rate of fruit decay and softening was higher in PE film treated fruits than in the other treatments. However, there was no decay detected in AVG treated fruit. The early harvested fruits were maintained higher flesh firmness, compared with mature harvested fruits. Nevertheless, the mature harvested fruits showed much higher soluble solids content, the redness (Hunter a value) of the fruit peel and respiration rate, compared with early harvested fruits. Furthermore, the rate of weight loss in the fruit was remarkably inhibited in the PE film treatment.

• Applied Chemistry for Engineering
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• v.16 no.6
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• pp.809-814
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• 2005

In this work, the thermal properties of epoxy coating system on the liner plate in the containment structure of nuclear power plants had been examined by irradiation and design basis accident (DBA) conditions. The effect of immersion in hot water on adhesion strength of the coating system had been also studied. The glass transition temperature ($T_g$) and thermal stability of ET-5290/carbon steel A 32 epoxy coating systems were measured by DSC and TGA analyses, respectively. Contact angle measurements were used to determine the effect of immersion on the surface energetics of epoxy coating system, with a viewpoint of surface free energy. Adhesion tests were also executed to evaluate the adhesion strength at interfaces between carbon steel plate and epoxy resins. As a result, it was found that the irradiation led to an improvement of internal crosslinked structure in cured epoxy systems, resulting in significantly increasing the thermal stability, as well as the $T_g$. Also, the immersion in hot water made a role in the post-curing of epoxy resins and increased the mechanical interlocking of the network system, resulting in increasing the adhesion strength of the epoxy coating system.

• The Journal of Korean Academy of Prosthodontics
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• v.51 no.2
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• pp.73-81
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• 2013

Purpose: The purpose of this study was to evaluate the effect of surface treatment on the shear bond strength of zirconia ceramic to 3 resin cements. Materials and methods: A total of 143 disk-shaped Zirconia blocks (HASS Co., Gangneung, Korea) were randomly divided into three treatment groups: (1) only 50 ${\mu}m$ $Al_2O_3$ sandblasting, (2) 50 ${\mu}m$ $Al_2O_3$ sandblast and zircona liner, (3) 50 ${\mu}m$ $Al_2O_3$ sandblasting and Rocatec (3M ESPE, Seefeld, Germany). Bistite II (Tokuyama Dental Co., Japan), Panavia F (Kuraray Medical, Japan), and Superbond C&B (Sun Medical, Japan) were used to cement onto the zirconia. After 24h of storage in distilled water, shear bond strength was evaluated. High value group was re-tested after thermocycling at 5,000 cycles(5-$55^{\circ}C$). Shear bond strength data were analyzed with one-way ANOVA, two-way ANOVA test and Post Hoc Test (${\alpha}$=.05). Shear bond strength data before and after thermocycling were analyzed with Independent sample T test (${\alpha}$=.05). Results: Super-bond C&B treated with Rocatec showed the most high shear bond strength. Super-bond C&B groups resulted in significantly higher than other cement groups (P<.05). Rocatec groups resulted in significantly higher than other surface treatment groups (P<.05). Shear bond strength has increased in Panavia F treated with Zirconia liner (P<.05). After thermocycling, shear bond strength was increased in Super-bond C&B treated with Rocatec but decreased in other groups (P<.05). Conclusion: Super-bond C&B cement resulted the highest shear bond strength and Rocatec system enhanced the shear bond strength. After thermocycling, shear bond strength has decreased in most resin cements except Super-bond C&B treated with Rocatec.

• The Journal of Korean Academy of Prosthodontics
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• v.56 no.4
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• pp.269-277
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• 2018

Purpose: This study examined the effects of glass infiltration treatments on the shear bond strength (SBS) between zirconia core and ultra low-fusing porcelain veneer. Materials and methods: The zirconia specimens were classified into 4 groups (n = 12): Untreated zirconia (group Z), zirconia coated ZirLiner (group ZL), glass-infiltrated zirconia (group ZG), glass-infiltrated and sandblasted zirconia (group ZGS). A cylinder of ultra low-fusing veneer porcelain was build up on each disk ($6mm{\times}3mm$). SBS was measured using a universal testing machine. Scanning electron microscope and Energy Dispersive X-ray spectroscopy were used to evaluate the surface of zirconia and failure pattern after SBS. Results: SBS value of group ZGS was significantly lower than that of other groups (P < .05). No significant differences were detected among group ZL, group Z and group ZG. Conclusion: Glass infiltration is not effective to the bond strength between zirconia and ultra low-fusing porcelain veneer. Sandblasting also dramatically decreased the bonding strength.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.4
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• pp.69-75
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• 1999

This study was performed to investigated the application of mixed resins for corrugated container board. The corrugated container board yields a sandwich structure in which a linerboard material is glued to a corrugated medium . Now, manufacturing corrugated container boards don't provide sufficient strength, and result in box failure during shipping . Therefore improvement of box strength is necessary . In this study, we intend to improve box strength by improving corrugated medium strength with mixed resins and to find the optimum treatment condition of this resins. First, we tried to mixed resins as Starch+CMC, Starch_Irea, CMC+Urea, Second, investigated to applicability of this resins for corrugated medium , and the third, measured tensile index, burst index, and edgewise compression index on liner, medium paper, and single faced corrugated container board. In this test results, we obtained that the improvement ratios of tensile index in liner and medium paper were approximately 80-185%, 60-118% , respectively. The respecting improvement ratios of edgewise compression index of single faced corrugated container board was approximately 91-124%, relatively. In addition, we concluded that optimum condition in mixing ratio was 1 :3 with CMC + Urea and the ap[plication amounts was 9% on materials. Fro manufacture of corrugated container board, optimum condition in mixing ratio was 1 : 3 with 5% CMC +Urea , because of considering to improvement of strength on cost.

• Restorative Dentistry and Endodontics
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• v.26 no.1
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• pp.51-63
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• 2001

In order to know the effect of dentin bonding agents on the restoration of cervical abrasion, Scotchbond Multipurpose Single Bond and Clearfil Liner Bond 2 were used in 51 teeth with abrasion lesion and normal teeth. The surface structure and dentinal tubules of acid etched dentin and resin replica were examined using scanning electron microscopy. The interfacial morphology between dentin and adhesives was investigated by confocal laser scanning microscopy. Following results were obtained. 1. The hybrid layer and resin tag of the dentin showing cross-sectional surface of dentinal tubules are thicker and longer than those of dentin showing oblique surface of dentinal tubules. 2. The sclerotic cast was frequently observed in dentinal tubule, and the cast looked like cuboidal or rhomboidal-shaped crystals clumped from outer side to inner side. 3. The formation of hybrid layer and resin tag was the most prominent in Scotchbond Multipurpose group, whereas Clearfil Liner Bond 2 group showed very poor formation. The formation of hybrid layer and resin tag in Single Bond group was less than Scotchbond Multipurpose group.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.9
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• pp.1251-1255
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• 2006

To improve the water resistance and physical properties of soy protein isolate (SPI)-coated paper, effects of concentrations of soy protein isolate and plasticizer were examined. Physical properties such as elongation strength (ES), elongation rate (E), water vapor permeability (WVP), and water solubility (WS) were evaluated. The film made from 5% soy protein isolate (SPI) and 40% glycerol (plasticizer) suggested a good application for a film preparation. SPI coated paper showed the highest ES (21.62 MPa) and the lowest WVP $(2.06ng{\cdot}m/m^2{\cdot}s{\cdot}Pa)$ and WS (1.17%). This study suggested that soy protein isolate (SPI) can be used as a coating material for the coated paper to improve the water resistance.