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The purpose of this paper is to investigate the influences of coating colours and their contents on the fundamental properties of base papers and also evaluate these results in terms of mechanical and wood-free papers.

A design research approach has been based on the application of various coating colours and analysis of mechanical and optical tests results of the coated mechanical and wood-free base papers.

This study is confirmed that the coating colours can be easily applied to the surface of the papers. The experimental data have revealed that significant improvements exist in the values of tear resistance (strength), brightness and opacity of the mechanical base papers, especially by the application of the coating colours including kaolin pigment. The results show that mechanical papers can also be used in areas with high brightness expectations by applying coating colour.

The originality of this work is based on understanding and comparing the effects of applying similar coating formulations on mechanical and wood-free base papers.

This paper aims to focus on a comparison study of the visible stability of natural blue dye consisting anthocyanin molecules extracted from Clitoria ternatea in coating films.

The coating films were prepared by mixing the blue dye with poly(acrylamide-co-acrylic acid) in three different weight ratios. Samples were coded as 10PBA, 15PBA and 20PBA, where PBA is the abbreviation for poly acrylamide-co-acrylic acid, blue dyes and anthocyanin. The number at the beginning of each code represents the weight percentage of poly(acrylamide-co-acrylic acid) to natural blue dye. The mixtures were applied on separate glass substrates to form coating films. Another set of samples were prepared for the comparison study with a commercial acrylic clear coat (cc) applied on the surface of the 10PBA, 15PBA and 20PBA coating films. These coating films were coded 10PBAcc, 15PBAcc and 20PBAcc. The purpose of the clear coat is to observe how it affects the colour stability of the blue coating films with respect to time. All samples were exposed to the ultraviolet (UV) source, an 18 W Philips TL-D 18w/830 UV fluorescent lamp. The UV lamp was placed 15 cm above the surface of the samples for 35 days. The colour of the coatings was measured using CIE L*a*b* colour space coordinate.

The results obtained show 10PBA and 10PBAcc have the highest colour stability after 35 days of exposure to UV light. The reflectivity of the coating films was also measured during exposure to UV lamp. Reflectivity measurements also showed that 10PBA and 10PBAcc coating films had the highest reflective stabilities.

The potential of using natural blue dye consisting anthocyanin in coating film to obtain high colour stability.

The coating film developed in this work is suitable to be applied on glass substrates.

The application of anthocyanin dye extracted from the Clitoria ternatea L. as a colourant in coating films

The purpose of this study is to investigate the effects of a pigment coating on the mechanical properties of fluting paper.

Two different calcium carbonate pigments were used in the preparation of the coated color, precipitated calcium carbonate (PCC) and ground calcium carbonate (GCC). Fluting paper produced by recycling waste paper was used as base paper. The effects of PCC and GCC pigments on mechanical properties were compared. Ring crush test (RCT), corrugating medium test (CMT), corrugating crush test (CCT), tensile and burst strength tests were applied to the coated papers, and the results were compared to the mechanical properties of base paper.

The tensile and burst indices of the coated papers were found to be higher than base papers about 13.9% and 6.05%, respectively. While the coating process positively affected the RCT and CCT values, it did not show a significant impact on the CMT values. GCC, one of the pigments used in coating colors, had a more effective effect on the mechanical properties of fluting papers compared to PCC.

These results suggest that coating of fluting papers has a positive effect on mechanical properties and the use of GCC as a pigment is more effective than PCC.

The purpose of this paper is to improve anti-corrosion, self-cleaning, hydrophily and sterilization properties of aluminum (Al) alloy.

A multifunctional coating for medical external application on Al alloy had been prepared by anodic oxidation, electrolytic coloring silver (Ag) and sealed in boiling water with nano-sized titanium dioxide (TiO₂) particles. The multifunctional coating was characterized by X-ray diffraction, scanning electron microscope and energy dispersive spectroscopy. Other properties such as corrosion-resistance, wipe-resistance, hydrophilicity, photochemical decomposition and bactericidal antiseptic effect were also investigated.

The results demonstrate that a golden film with multi-function had been obtained for medical external application. The main phase of coating is amorphous Al₂O₃, and nano-sized silver particle is electrodeposited in bottom of film hole, while nano-sized TiO₂ is sealed on the external surface of coating. The properties of film, such as anti-corrosion, self-cleaning, hydrophily, sterilization are better than those of Al alloy substrate.

Considering about this usage for medical external application, a multifunctional coating which has the properties such as decoration, anti-corrosion, sterilize and self-cleaning has been first prepared on Al alloy surface in the study. This coating would meet the requirements of medical external using and provide theoretical and practical foundation about Al alloy for medical use.

The purpose of this paper is to investigate the effects of carbon nanotubes (CNTs) on the mechanical, thermal and colour properties of solvent-containing two-component polyurethane (PU) coating.

Fourier transform infrared spectroscopy and observation of dispersion stability were used to assess the effects of acid treatment on CNTs. The CNTs and PU composite coating was synthesised by in situ polymerisation and bending polymerisation, and the mechanical, thermal and colour appearance properties of coating were characterised.

It was found that desirable modifications to CNTs occurred after acid treatment; thus, mainly carboxylic acid groups were introduced onto the surface of CNTs. And the acid-treated CNTs could improve the mechanical and thermal properties of PU coating, and the properties of composite coating was improved more successfully by in situ polymerisation than by blending polymerisation.

The investigation established a method to synthesise CNTs and PU composite coating. The mechanical and thermal properties of PU coating could be improved by the inclusion of CNTs.

This study established a method to synthesise CNTs and PU composite coating by in situ polymerisation and blending polymerisation; the effects of CNTs on modifying mechanical, thermal and colour properties of PU coating were investigated and compared in detail.

The purpose of this paper is to observe the thermal and colour stabilities of coating films consisting of natural dye anthocyanin colourant with acid and nitrate salt as additives.

The natural dye was extracted from Hibiscus sabdariffa L. (Roselle) by using distilled water as solvent. The extracted dye was mixed with 1 weight per cent hydrochloric acid and 5 weight per cent calcium nitrate to conduct the comparison study. The dye samples were than mixed with poly (vinyl alcohol) (PVA). The mixtures were applied on glass panels to form coating films. The coating films were left to dry for 24 hours. The thermal stability of coating films was investigated by using thermogravimetric analysis (TGA). The amorphousness coating films molecular structures were observed by using x-ray diffraction (XRD). CIE L*a*b* colour coordinate space technique was used to investigate the coating films colour stability against ultraviolet (UV).

The results show that addition of hydrochloric acid (HCl acid) enhanced thermal stability of PVA-anthocyanin coating and shifted the degradation temperature to higher temperature at 300°C. HCl acid also improved UV stability of the coating system significantly with the reduced ΔE from 26.67 to 16.89. Addition of calcium nitrate (Ca(NO₃)₂) salt promotes good interaction with PVA-anthocyanin system that caused structural changes, improved thermal stability and increased T_g from 61.5 to 83.1°C.

The potential of using natural dye extracted from plant as renewable material.

The coating films developed in this works are suitable for glass substrate application.

Development of water-based coating from PVA binder with anthocyanin colourant is introduced in this study.

This paper aims to investigate the effect of titanium dioxide (TiO₂) nanoparticle coating on the visible reflectance and color appearance of dyed cotton fabrics.

A Taguchi experimental design model was used to minimize the number of samples and for accurate prediction of possible responses. The governing parameters affecting the color change of dyed fabrics through the coating process were selected as shade of cotton fabrics, depth of shade, concentration and size of TiO₂ nanoparticles and concentration of citric acid. The Taguchi model suggests the L18 orthogonal array. In the meantime, the lower response category was selected to determine the optimum conditions. According to obtained results, coating with TiO₂ nanoparticles results in color change (ΔEab*) of all dyed cotton fabrics.

The obtained results indicate that the TiO₂-coated fabrics had higher reflectance compared to raw fabrics. Furthermore, it was found that the TiO₂ pigmented coating increases the brightness of samples and simultaneously decreases their chroma. On the other hand, analysis of variance reveals that the concentration of TiO₂ nanoparticles together with shade of fabrics has the most significant impact on the color change of dyed fabrics through coating process. Dye concentration and size of TiO₂ particles also, to the same extent, had influence over the color change. However, the effect of the concentration of citric acid on the color change was insignificant.

This research investigates the effect of TiO₂ nanoparticles on the optical property of colored fabric by using a Taguchi experimental design model to minimize the number of samples.

Over the last few years, the share of powder coatings used for the protection of aluminium extrusions and claddings for architectural uses in competition with conventional liquid paints and as an alternative to anodising has sharply increased. In 1987, about 47 million m2 or 135 thousand tons of aluminium used in outdoor architecture have been powder coated in France, Germany, Italy and United Kingdom. This paper gives a thorough description of the latest developments of the polyester powder coating systems used for aluminium extrusions and claddings in Europe, underlining the criteria of the choice of the weathering resistant powders, the importance of metal pretreatment and of the coating process itself as well as of the quality control in this industry. A comparison with competitive coating technologies is also given.

The interest in waterborne coatings continues, and this trend is well‐demonstrated by many new proprietary products. For example, a new acrylic latex enamel has been announced which has high gloss and superior colour retention. Associated with the product are the usual properties of easy application, low odour, and water cleanup. The product is available from the O'Brien Corp. [450 E. Grand Ave., So., San Francisco, CA 94080].

The purpose of this paper is to observe the colour and thermal stability of natural red dye consisting of anthocyanin with addition of different aqueous acids and applied as coating films.

The natural red dye was extracted from Hibiscus sabdariffa L. (roselle) flowers and mixed with 1 per cent hydrochloric acid, 5 per cent acetic acid, 5 per cent citric acid and 5 per cent oxalic acid. All the dye samples were exposed to heat and UV-B to observe the colour stability by calculating the half-life and rate of reaction. In coating film application, each of the dye samples was mixed with 25 wt% of poly(vinyl alcohol) (PVA) and applied on to a glass substrate. The coating samples’ colour stability was observed by using CIE L*a*b* colour space coordinates. The coating films’ weight loss stability against temperature was observed by using thermogravimetric analysis.

Addition of hydrochloric acid enhances the thermal and UV stability of the anthocyanin natural dye. This can be observed from the calculation of the half-life of the dye. The half-life values for the thermal and UV stability studies were 1,155 hours and 210 hours, respectively. In coating films, the sample with addition of acetic acid showed the highest colour stability with colour difference (ΔE*) value 8.95.

The coating films developed in this work are not suitable to be applied on metal substrates due to the presence of water, which can contribute to the corrosion formation.

The coating films developed in this work are suitable for washable coating application. In other words, they are non-permanent coatings applied on a glass substrate.

Development of water-based coatings from PVA binder with anthocyanin colourant is introduced in this study.