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The purpose of this paper is to report on a method of synthesis of TiO₂‐SiO₂ oxide composites characterised by spherically shaped particles with sizes in the micrometric ranges, which can be applied as a new generation of textile/TiO₂‐SiO₂ composites with barrier properties against UV radiation. Synthesis and characterisation of TiO2‐SiO2 oxide composites with a high degree of dispersion were performed, and their influence on the barrier properties of textile fabrics was investigated.

The precipitation was performed with the use of solutions of titanium sulphate and sodium silicate as the precipitating agent, which are cheap alternatives to organic precursors of Ti and Si. The reaction was conducted in an emulsion system, where cyclohexane was used as the organic phase and non‐ionic surfactants NP3 and NP6 as emulsifiers were applied.

The direction of substrate supply, concentration of the reagents and their ratio and other conditions of precipitation process were found to significantly affect the physicochemical parameters of the pigments obtained. A possibility is provided of manufacturing a new generation of textile/TiO2‐SiO2 composites with barrier properties against UV radiation.

Titanium sulphate, sodium silicate, cyclohexane as the organic phase, and non‐ionic surfactants NP3 and NP6 as emulsifiers, were used.

Synthesis of a new generation of textile/TiO2‐SiO2 composites with barrier properties against UV radiation has been performed. Textile fabrics modified with hybrid composites demonstrated high absorption of UV radiation over the full wavelength range.

Determination of optimum conditions of TiO2‐SiO2 oxide composites precipitation to obtain products with desired physicochemical, dispersive and structural properties. Development of nano‐structural textile composites with barrier properties, protecting against UV radiation.

This study aims to improve the natural dyeing recipe with better light fastness using ascorbic acid (vitamin C) with pulverised plant dyes.

Silk fabrics pre-mordanted with alum (aluminium ammonium sulphate) were dyed using six types of plant dyes available in Sarawak, Malaysia, namely, Engkerabai leaves (Psychotria viridiflora), Ketapang leaves (Terminalia catappa), mangrove bark (Ceriops tagal), Sepang wood (Caesalpinia sappan), mangosteen husk (Garcinia mangostana) and onion skin (Allium cepa). Then, the dyed samples were immersed in vitamin C. The dyed and vitamin C-treated silk samples were exposed to direct sunlight for 40 h to test whether vitamin C had any effect on the light fastness of the dyed samples.

It was found that the fabric samples using vitamin C for after-treatment, particularly Engkerabai, Ketapang, mangrove and mangosteen, exhibited better light fastness. The colours of the four samples changed and looked darker when compared to the non-treated fabric samples. However, it was observed that vitamin C had a reverse effect on Sepang wood and onion skin. The acidic aqueous solution of vitamin C discharged the dyed samples instead.

In conclusion, depending on the plant types, vitamin C can be used to improve the light fastness of natural dyes or as a reducing agent for natural dyes.

The incidences of skin cancer have been rising worldwide due to excessive exposure to sunlight. Increase in exposure to ultraviolet (UV) radiation from sunlight results in skin damage such as sunburn, premature skin ageing, allergies and skin cancer. Medical experts suggest several means of protection against ultraviolet radiation, including use of sunscreens, avoidance of the sun at its highest intensities, and wearing clothing that covers as much of the skin surface as possible. This paper provides insight on how UV absorbers can be efficiently used with textile material to protect human skin from harmful UV radiation. The manufacturers of various UV absorbers and their commercial products are reviewed and discussed. The interacting mechanism of UV absorbers with textile clothing for providing UV protection and an evaluation of the performance of UV absorbers are summarized.

The purpose of this paper is to evaluate the potential of natural colourants from fruits of Ixora siamensis for coating applications, to study its glossiness and effectiveness against UV‐B irradiation.

In this study, natural colourants from the fruits of Ixora siamensis were extracted using trifluoroacetic acid‐methanol solution. Anthocyanins and organic acid variants were mixed together to form co‐pigments. Different concentrations of ferulic and gallic acid co‐pigments were added to a blended solution of poly (vinyl alcohol), PVA and anthocyanin (from Ixora siamensis) to form a coating system. The coatings were exposed to UV‐B irradiation at room temperature in air using a UV‐lamp which emitted radiation at 312 nm. The effects of UV‐B irradiation on the coating system were evaluated using glossiness test and UV‐visible spectroscopy.

Anthocyanins are unstable and can quickly lose their colour. One of the methods of preserving the stability of these pigments is by co‐pigmentation. Co‐pigmentation of anthocyanin with organic acid variants resulted in an increase in both hyperchromic effects (ΔA) and bathochromic shifts (Δλ). In this study, ferulic acids yielded better results compared to gallic acids.

Samples with co‐pigmentation give better result compared to the untreated samples. The addition of 0.5 and 1.0 per cent ferulic acid improves the gloss properties and resistivity of the samples towards the UV irradiation. Thus, in order to study the effectiveness of ferulic acid as additive and improving the properties of the samples, the percentage of ferulic acid added and exposure time could be increased.

The method developed provided a simple and efficient solution for improving the UV resistance of anthocyanin blend with poly (vinyl alcohol), PVA UV absorber. Effect of ferulic acid as UV absorber, if added in more concentration, can be further studied for optimization.

The social implication is the use of local plant species as a low cost source of natural pigments in coating system.

The method for improving the resistance towards UV irradiation of anthocyanin blend with poly (vinyl alcohol), PVA was novel and could find numerous applications for natural product based on plant pigment.

The purpose of this study is to investigate the possibility of dyeing polyester (PET) fabric with natural dye extracted from annatto seeds using high temperature dyeing method.

PET fabric was dyed with annatto extract by varying dyeing parameters (temperature, time, pH and dye concentration) to determine the optimum dyeing conditions. The influences of KAl(SO₄)₂, FeSO₄, gallnut mordants or a commercial UV absorber on colour yield and fastness properties were further studied.

Optimum results were obtained when the fabric was dyed at 130°C for 30 min in a dyebath containing 15 per cent (owf) annatto dye at pH 6. The dyed fabric had an orange shade and exhibited good to excellent wash, crock, perspiration fastness and fair light fastness. Further dyeing with mordants or UV absorber mostly resulted in lower colour yield and similar fastness properties.

Although the light fastness was slightly improved to moderate level for the sample with UV absorber, a noticeable colour staining on cotton portion of multi-fibre fabric occurred when subjected to standard washing test. Compared to C.I. Disperse Orange 73, the annatto dye exhibited comparable colour fastness but had inferior light fastness when dyed at approximately the same colour strength.

Natural colourants from annatto seeds can be used to dye PET fabric at high temperature without mordants, yielding deep orange shade and satisfactory fastness properties. This study provides a promising application to reduce the environmental impact of synthetic dyes.

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.

Synthesis and evaluation of new naphthopyran and related compounds as ultraviolet absorbers.

The new naphthopyran and related compounds were prepared using new synthesis methodology which gave new derivatives via positions not accessible by traditional methods.

A new method for the preparations of naphthopyran was developed. The naphthopyran compounds prepared had promising UV absorption/protection capabilities.

The new compounds synthesised had unique character enabling them to be used in applications such as UV absorber and sunscreen.

New method of synthesis and the possibility of using the naphthopyran derivatives as UV absorber in many applications.

The purpose of this paper is to test absorption characteristics of some newly synthesised 4‐hidroxycoumarins, containing phenyl‐prop‐2‐enoyl group at the 3‐position. Change in spectral characteristics in solvents of different polarity (chloroform and acetonitrile) was followed in regard to the influence of the substitution at the phenyl ring and influence of concentration H⁺ ions. Effectiveness of tested substances was compared with well‐known UV absorbers such as benzophenone‐3 and butyl methoxydibenzoylmethane (BMDM).

All the tested substances were dissolved in chloroform and acetonitrile, with 10‐3 mmol concentration range. The pH was adjusted using 0.1 mol/l HCl, glacial acetic acid, 0.1 mol/l NaOH (aqueous solution) and 0.1 mol/l NaOH (methanolic solution). Spectrophotometric measurement was recorded in the range of 200‐800 nm, using 1‐cm quartz cells.

The tested 4‐hydroxycoumarin derivatives showed good UV absorption properties in the range 280‐380 nm. Substitution on the phenyl ring changes the shape of the absorption maxima. The changes depend on the properties of the substituent as well as the acidity of the solution.

Introducing an electron‐donating substituent on the phenyl‐prop‐2‐enoyl group can shift absorption maximums to longer wavelength. In addition, the variation in substituents on the synthesised substances and pH of the solution could also be studied.

The new compounds showed good UV absorption, making them potential candidates for many applications. The practical importance of the tested substances are derived from their stability, relatively easy synthesis and good UV absorption properties.

The paper shows that the tested coumarins derivatives were new compounds with good UV absorption properties, making them good UV absorbers of commercial potential. The tested coumarins showed good UV absorption properties in the range 280‐380 nm, making them potential candidates for many applications.

This review deals with the pros and cons of ultraviolet (UV) radiation on human beings and the role of textile clothing and the chemicals used for textiles to protect from their harmful effects.

UV radiation (UVR) which has further divided into UVA, UVB, and UVC. Almost 100% of UVC and major portion of UVB are bounced back to stratosphere by ozone layer while UVA enters the earth atmosphere. Excessive exposure of solar or artificial UVR exhibit potential risks to human health. UVR is a major carcinogen and excessive exposure of solar radiation in sunlight can cause cancer in the lip, skin squamous cell, basal cell and cutaneous melanoma, particularly in people with the fair skin.

This article aims to provide a comprehensive overview of the harmful effects of UVR on human skin, factors affecting UV irradiance and factors affecting UV protection offered by textile clothing.

Effect of fiber properties, yarn properties, fabric construction, fabric treatments and laundering has been reviewed along with the identification of gaps in the reported research. A comparison of inorganic and organic UV absorbers has also been given along with different testing and evaluation methods for UV protective clothing.

Coatings are subject to photoaging during their lifetime. Ultraviolet radiations absorbing additives (UVAs) and hindered amine light stabilisers (HALS) often are added to improve their performance. To improve performance of coatings, it is important to use optimum quantity of such additives.

In this study, hydroxyl‐terminated polyester was synthesised and then crosslinked using isophoronediisocyanate. These clear coats were then stabilised with various additives such as Tinuvin 1130, 123 and 292. The synergistic effect of these additives was also studied. The optical properties of coatings such as yellowness, whiteness and gloss of coatings were studied after exposing these coatings to various environments such as QUV weathering, direct UV and xenon arc.

The results showed that the coatings stabilised with combination of additives performed better than the unstabilised coatings as well as single additive coatings. A synergism was observed when using a combination of the UVAs and HALS.

The additives used were found to be compatible with the binder systems under study and was not found to be universally compatible with all resins.

UV degradation is a major concern in coatings both aesthetically and functionally. This study aimed at optimising the concentrations of UV stabilisers in order to increase the effective life time of exterior coatings.

UV stabilisers are routinely used in coatings for exterior applications. However, our aim was to optimise the concentrations of these additives in the coating so as to reduce the cost while keeping the performance of the coatings unaffected. By studying the synergy of the additives, we have also optimised their concentrations to further increase the life of the coatings.