• Applied Chemistry for Engineering
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• v.8 no.3
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• pp.510-516
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• 1997

O/W emulsions were prepared by adding water to the solution containing amphiphilic resin and the mixed emulsifier of cetyl alcohol polyoxyethylene(20) sorbitan monooleate. Phase behavoir of these emulsions was studied at various HLB(Hydrophilic Lipophilic Balance) values and temperatures. The polar oil emulsion containing the amphiphilic resin showed improved phase stability at various temperatures. Model compounds which contain one of the functional groups in the amphiphilic resin were used in the polar oil phase in order to study the effect of interaction between the functional group and the emulsifier on the phase stability of emulsion. These model compound emulsions showed the phase stability order of poly(acrylic acid)

• Restorative Dentistry and Endodontics
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• v.22 no.1
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• pp.132-143
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• 1997

Recently composite resin luting cement have been widely used according as esthetic requirement was increased. The purpose of this study was to evaluate of shear bond strength of four resin cements to bovine dentin. The materials used in this study were All-Bond 2(dentin bonding agent), Duolink cement, Bistite resin cement, Twinlook cement, Clearfil CR inlay cement. A total 40 acrylic cylinders with bovine dentin were divided into four groups. Four experimental groups were as follows; Group l(AB) : Specimens bonded with All-Bond 2 and Duolink Cement Group 2(BT) : Specimens bonded with Bistite Resin Cement Group 3(TL) : Specimens bonded with Twinlook Cement Group 4(CR) : Specimens bonded with Clearfil CR Inlay Cement Mter 1 hour of bonding, all specimens were stored for 24 hours in water at $37^{\circ}C$ and tested with Instron universal testing machine between bovine dentin and resin cements. The data were evaluated statistically at the 95% confidence level with a one-way analysis of variance and Tukey's range statistics. The following results obtained; 1. The group l(AB) was highest shear bond strength and the group 3(TL) was 10west(p>0.05). 2. Group 2(BT), 4(CR) were similar shear bond strength and there was no significant difference(p<0.05). 3. Group 1(AB), 4(CR) with acid etching were showed resin tags on the opened dentinal tubules, but Group 2(BT), 3(TL) without acid etching were not showed resin tags. 4. Group l(AB) was showed intimate adaptation than other groups.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.468-476
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• 1998

The purpose of this study was to observe the morphologic change of dentinal surface, adhesion in interface between dentin and bonding agents, and penetration pattern of resin tags into dentinal tubles according to bonding procedure of ONE-STEP universal adhesive system. Ten extracted human molars were mounted in dental stone and sectioned to expose mid-coronal occlusal dentin and again sectioned tooth crown apically. Specimens were randomly assigned to three groups for dentin conditioning with 32% phoshoric acid, two coats of bonding agents after dentin conditioning, and bond of composite resin. The surfaces of dentin were treated with etch ant and applied bonding agent, and bonded composite resin according to the directions of manufacturer. Specimens which were boned composite were sectioned longitudinally for observing interfaces between resin and dentin. Two of specimens which were sectioned longitudinally were immersed in 6 N HCL for 30 seconds and 1% NaOCL for 12 hours to partially demineralize and deproteinize the dentin substrate. Each specimen was mounted on a brass stub, sputter-coated with gold and observed under SEM. The result were as follows : 1. On the dentinal surface which was conditioned with 32% phosphoric acid. the smear layer was completely removed. orifices of dentinal tubules were opened 3-$5{\mu}m$ wide. and dentinal surface was irregular. 2. On the dentinal surface which was applied ONE-STEP. bonding agent. resin particles were observed on the orifices of dentinal tubules and intertubular dentin. 3. There were close adaptation between dentin and resin and were the pattern which composite invaded into dentin. 4. 1-$3{\mu}m$-wide hybrid layer was visible in the interface between dentin and resin. 5. Long and funnel shaped resin tags were observed in demineralized specimens. and the surfaces of tags were rough.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.3
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• pp.375-389
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• 2022

3D printing has been considered a key technology, leading the fourth industrial revolution. However, 3D printed textile still has a lot of limitations to overcome before it can be adopted as a clothing material in terms of design, flexibility and dyeability. This study aims to provide modeling design for imparting the flexibility and post-dyeing process for 3D printed textiles. The modeling types were designed to test the flexibility of 3D printed textiles. The post-dyeing process was evaluated through dye absorption depending on the resin and modeling types, respectively. The results were as follows: two types of modeling (Modeling A and B) were designed with a ring structure to test the flexibility of the 3D printed textiles. The 3D printed textiles with ring-based structure Modeling A had flexibility regardless of the hardness of resin types. In the dyeability test, softening resin (S-Resin) and hardening resin (H-Resin) were found to have good dyeability with acid dye and direct dye, respectively. The condition of S-Resin with acid dye and H-Resin with direct dye was controlled by dye absorption rate.

• Restorative Dentistry and Endodontics
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• v.18 no.1
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• pp.73-83
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• 1993

The purpose of this study was to evaluate the effect of various acid treatments on dentin bonding. Freshly extracted human teeth were uprightly embedded in self curing acrylic resin, and their occlusal surfaces were grinded to expose flat dentin surfaces. The specimens were divided into 4 groups. Specimens of one group were not treated so as to be a control and those of the other three groups were threated with 10% polyacrylic acid, 10% phosphoric acid, and 10-3 solution(10% citric acid/3% ferric chloride) respectively. Primer, bonding resin and composite resin were applied over the treated dentin surfaces sequentially. All specimens were stored in $37^{\circ}C$ distilled water for 24 hours, then the tensile bond strength was measured and the treated dentin surfaces and fracured dentin surfaces were examined under a scanning electron microscope. The results were as follows: Bond strengths of acid-treated groups were higher than those of the untreated group. In the acid-treated groups, bond strength was found to be the highest in the 10-3 solution group followed by the 10% phosphoric acid group and the 10% polyacrylic acid group(P<0.01). On SEM examination of dentin surfaces, the untreated dentin surface showed a remaining smear layer and closed dentinal tubules. Dentin surfaces treated with 10 % polyacrylic acid showed a clean dentin surface without the smear layer, but showed remaining smear plugs in dentinal tubules. A dentin surface treated with 10% phosphoric acid or 10-3 solution showed open dentinal tubules without the smear layer or smear plugs. On SEM observation of the fractured dentin-resin interface, the untreated group showed that failure occurred in the smear layer. The group treated with 10% polyacrylic acid showed no resin tag remained in the dentinal tubules, but resin tags in the dentinal tubules were observed in the group treated with the 10% phosphoric acid or the 10-3 solution. On the failure mode examination, the higher the bond strength of the group, the higher the frequency of cohesive failure. The coefficient between bond strength and cohesive failure rate was 0.71.

• Journal of the Korean Wood Science and Technology
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• v.16 no.2
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• pp.79-89
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• 1988

This experiment was carried out to investigate the difference of compositions between petroleum ether extract and its tall oil in Pinus rigida Mill. xylem and to obtain the basic data on effective extraction and its utilization of by-product, resin and fatty acid, when pulp making. After both petroleum ether extract from wood meal and its tall oil in pitch pine were separated to the resin and fatty acid by using DEAE-Sephadex and aluminum oxide column, these were analyzed with gas chromatograph. The results obtained were as follows: 1. Fatty acids contained as ester form in living trees were varied by peroxide of organic solvent in petroleum ehter extraction and cooking chemicals in cooking. 2. Pimaric-type acid was eluted earlier than abietic-type acid in resin acids and the fewer the carbons, the earlier the elution in fatty acids. 3. The retention time of SE-30 column was even smaller than that of OV-101 column but the relative retention time obtained by using methyl pimarate and methyl stearate as internal standard was nearly identical. 4. Both petroleum ether extract and tall oil mainly consisted of resin acids, expecially abietic-type acid. 5. Tall oil had more fatty acid but less resin acid than petroleum ether extract. Also, the content of unidentified materials was increased owing to the isomerization and the shift of double bond position in unsaturated fatty acids by high temperature and cooking chemicals when cooking.

• The Journal of Advanced Prosthodontics
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• v.5 no.4
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• pp.479-484
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• 2013

PURPOSE. The aim of this study was to evaluate the effects of additional acid etching and curing mechanism (light-curing or self-curing) of a composite resin on the dentin bond strength and compatibility of one-step self-etching adhesives. MATERIALS AND METHODS. Sixteen human permanent molars were randomly divided into eight groups according to the adhesives used (All-Bond Universal: ABU, Clearfil S3 Bond: CS3), additional acid etching (additional acid etching performed: EO, no additional acid etching performed: EX), and composite resins (Filtek Z-250: Z250, Clearfil FII New Bond: CFNB). Group 1: ABU-EO-Z250, Group 2: ABU-EO-CFNB, Group 3: ABU-EX-Z250, Group 4: ABU-EX-CFNB, Group 5: CS3-EO-Z250, Group 6: CS3-EO-CFNB, Group 7: CS3-EX-Z250, Group 8: CS3-EX-CFNB. After bonding procedures, composite resins were built up on dentin surfaces. After 24-hour water storage, the teeth were sectioned to make 10 specimens for each group. The microtensile bond strength test was performed using a microtensile testing machine. The failure mode of the fractured specimens was examined by means of an optical microscope at ${\times}20$ magnification. The data was analyzed using a one-way ANOVA and Scheffe's post-hoc test (${\alpha}$=.05). RESULTS. Additional etching groups showed significantly higher values than the no additional etching group when using All-Bond Universal. The light-cured composite resin groups showed significantly higher values than the self-cured composite resin groups in the Clearfil S3 Bond. CONCLUSION. The additional acid etching is beneficial for the dentin bond strength when using low acidic one-step self-etch adhesives, and low acidic one-step self-etch adhesives are compatible with self-cured composite resin. The acidity of the one-step self-etch adhesives is an influencing factor in terms of the dentin bonding strength and incompatibility with a self-cured composite resin.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.3
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• pp.290-298
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• 2018

This study aimed to evaluate surface morphology and resin tag penetration of resin infiltration into primary anterior teeth after enamel deproteinization with sodium hypochlorite (NaOCl) prior to phosphoric acid ($H_3PO_4$) etching. Ninety primary anterior teeth with non-cavitated caries lesion were devided five groups according to enamel pretreatment as follows, group I-15% hydrochloric acid (HCl) 2min. ; group II-5.25% NaOCl 1min., 35% $H_3PO_4$ 1min. ; group III-5.25% NaOCl 2min., 35% $H_3PO_4$ 1min. ; group IV-5.25% NaOCl 1min., 35% $H_3PO_4$ 2min. ; group V-5.25% NaOCl 2min., 35% $H_3PO_4$ 2min. Fifteen teeth were examined etched surface structure using field emission-scanning electron microscope. Seventy five teeth were infiltrated with resin, maximum penetration depth and percentage penetration were analysed using dual fluorescence confocal microscopy. As the application time of NaOCl increased, ratio of enamel type I, II were increased. Percentage penetration (PP) was higher in group V than group II, III (p < 0.05). PP of group IV, V did not show any differences. Non-cavitated caries of primary anterior teeth can be treated with resin infiltration. Enamel deproteinization with NaOCl prior to 35% $H_3PO_4$ etching could be an alternative of 15% HCl etching in resin infiltration.

• Polymer(Korea)
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• v.34 no.1
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• pp.52-57
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• 2010

The low viscous epoxy resin(bisphenol F) with carboxylic acid as the reductants was introduced for high performance and reliability in the ACA with a low melting point alloy filler system. The curing characteristics of the epoxy resin and temperature dependant viscosity characteristic of epoxy resin at the melting temperature of LMPA were investigated by dynamic mode of differential scanning calorimetry (DSC) and rheometer, respectively. Based on these thermo-rheological characteristics of epoxy resin and LMPA, the optimum process system was designed. In order to remove the oxide layer on the surface of LMPA particle, three different types of carboxyl acid-based reductant were added to the epoxy resin. The wetting angles were about $18^{\circ}$ for carboxypropyldisilioxane, and $20.3^{\circ}$ for the carboxy-2-methylethylsiloxane, respectively.

• The Journal of Advanced Prosthodontics
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• v.5 no.3
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• pp.248-255
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• 2013

PURPOSE. This study compared the effect of three intraoral repair systems on the bond strength between composite resin and zirconia core. MATERIALS AND METHODS. Thirty zirconia specimens were divided into three groups according to the repair method: Group I-CoJet$^{TM}$ Repair System (3M ESPE) [chairside silica coating with $30{\mu}m$ $SiO_2$ + silanization + adhesive]; Group II-Ceramic Repair System (Ivoclar Vivadent) [etching with 37% phosphoric acid + Zirconia primer + adhesive]; Group III-Signum Zirconia Bond (Heraus) [Signum Zirconia Bond I + Signum Zirconia Bond II]. Composite resin was polymerized on each conditioned specimen. The shear bond strength was tested using a universal testing machine, and fracture sites were examined with FE-SEM. Surface morphology and wettability after surface treatments were examined additionally. The data of bond strengths were statistically analyzed with one-way ANOVA and Tamhane post hoc test (${\alpha}$=.05). RESULTS. Increased surface roughness and the highest wettability value were observed in the CoJet sand treated specimens. The specimens treated with 37% phosphoric acid and Signum Zirconia Bond I did not show any improvement of surface irregularity, and the lowest wettability value were found in 37% phosphoric acid treated specimens. There was no significant difference in the bond strengths between Group I ($7.80{\pm}0.76$ MPa) and III ($8.98{\pm}1.39$ MPa). Group II ($3.21{\pm}0.78$ MPa) showed a significant difference from other groups (P<.05). CONCLUSION. The use of Intraoral silica coating system and the application of Signum Zirconia Bond are effective for increasing the bond strength of composite resin to zirconia.