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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.

Novel coumarines having an ester group in position 4 had been prepared via a new methodology utilising ylides. Such a new method made it possible to prepare a new class of bis coumarines. The new coumarins derivative obtained showed good UV absorption properties in the range of 250‐410 nm making them good UV absorbers of commercial potential.

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.

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.

The onslaught of automation in the industrial coatings area is an irreversible one. For this reason, the manufacturers who coat in‐plant seize eagerly upon developments such as high‐energy radiation curing and ultraviolet curing. Interest in these techniques is developing rapidly as indicated by the large number of patents which are beginning to evolve. The advantages of these methods have been detailed in previous reviews. Some of the more recent literature is described in this article.

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 growing interest in the use of fluorescent pigments has been partly brought about by an increasing awareness of safety considerations, and also because pigments in either paints or inks provide a striking contrast to the normal range of paints on which they may be superimposed. This feature can be utilised in advertising posters where eyecatching appeal can be particularly rewarding.