Publication Sponsored by the Society's Fastness Tests Co-ordinating Committee-51 Colour Fastness to Shampooing of Textile Floor Coverings

For over fifteen years the UK carpet industry has used a test method for controlling the colour fastness to shampooing of carpets. The carpet manufacturers, in conjunction with dye makers, originally developed the test for wool carpets of the Axminster type, in which deep colours lay side by side with ecru or pale colours. Later the procedure was extended to wool I nylon mixtures. In many cases at the end of the dyeing stage, the yarn is left in an acid condition, and to predict the effect of repeated shampooing the test solution is buffered in order to show what would happen as the carpet approaches a neutral pH condition. Throughout the use of this test, the laboratory procedure has been compared with domestic and contract shampooing. The following paper clearly shows this relationship and suggests that perhaps the title of the test method is misleading, since the major effect on the dyed carpets tested is due to the retention of the shampoo liquor and not to the method of shampooing.     

Apparent Colour Yield in Dyed Textiles

Various factors influence the visual efficiency of a fixed amount of colorant in a textile. The relevant optical phenomena are reviewed and treated in non-mathematical outline. The results of calculations on a number of simple optical models give rational bases for considering the qualitative effect on colour yield of the factors: fibre size and cross-section; incomplete penetration of colorant into the textile structure; colour-blended textiles; packing density of yarns and fabrics; polarization and fibre orientation; internal scattering and matt fibres; mechanical and added finishes; raised and pile structures; and ring-dyed fibres.     

Application of Tristimulus Colorimetry to the Prediction of Colour Fastness of Nylon Fibre

The colour fastness of melt-coloured nylon fibre exposed to various destructive influences is predicted. The conventional concepts of colorimetry are employed in making these fastness calculations. Results are given for predictions of fading after exposure to ultra-violet light, and after hypochlorite bleach treatment of the precoloured nylon fibre. The generality of the method is discussed. Application to other types of fastness calculations is suggested.     

Comparison of Sources for Light Fastness Testing

A number of fading sources have been examined with particular reference to the testing of materials of high light fastness. This work indicates that several light sources may be suitable for carrying out fastness tests on textiles, and anreconomical lamp is available.     

Publication Sponsored by the Society's Fastness Tests Co-ordinating Committee-52 Colour Fastness to Chlorinated Water (Swimming Bath Water)

Results obtained using the current standard test (BS 1006-.E03:1978) do not correspond adequately with the performance of representative dyeings from current ranges of fabrics used in chlorinated swimming pools. A revised test method is defined. It has been subjected to interlaboratory evaluation, to assess repeatability and reproducibility and compared with results from swimming pool trials. It has been shown to be satisfactory in both respects.     

Comparison of Light Fastness Assessments with the Microscal (Mercury Vapour Illuminant) Light Fastness Tester and Xenon Arc Illumination

Thirty-five dyed fabrics, representing eleven different dye-fibre combinations, have been tested for light fastness in the Microscal Light Fastness Tester, under illumination from the 400-W mercury vapour lamp, and to a 1500-Wxenon arc in a standard commercial machine. Evaluation of the results was made by a panel of nine observers, and mean gradings on the BSI scale were calculated. Alt but three of the dyeings gave ratings by the mercury lamp that were within three-quarters of a grade of those by xenon illumination, 17 of them being within one-quarter of a grade. The mercury lamp is therefore considered to be a satisfactory illuminant for commercial light-fastness evaluation; it would offer very considerable economies in operation. The three above-mentioned (all vat) dyeings were rated lower by between 1.2 and 1.4 mean grades with mercury compared to xenon illumination. Reasons are given for a suggestion that traces of an oxidant remaining from the dyeing operations may have been responsible for the more rapid fading in the mercury lamp. There is a possibility therefore that the mercury lamp may be useful in detecting colorations that might show anomalously rapid fading outdoors where there is a large proportion of violet and near-ultraviolet radiation.     

Some Observations on Colour Fastness to Washing with Particular Reference to Disperse Dyes on Polyester

In recent years there has been a trend away from the traditional soap-based washing tests towards methods based on commercial-type washing powders. Experience with tests based on washing powders, and the relationship between these tests and the traditional soap-based tests, are described. It is shown that the degree of staining of adjacent fabrics, particularly nylon, increases as the detergent concentration in the wash liquor is decreased. Post-stentering and the quality of fabrics used as adjacents in the wash test can have a considerable influence on the results.     

提高锦纶翠蓝染色的耐光色牢度

为了解决锦纶织物酸性翠蓝染色耐光色牢度低下的问题,本文研究了以直接耐晒翠蓝GL进行锦纶染色的工艺,通过试验得出合适的工艺为:染液pH值4,浴比为1∶ 20,染色温度95℃,染色时间30分钟;并与酸性翠蓝上染锦纶的色光、耐光色牢度、耐洗色牢度和耐摩擦色牢度进行对比,结果发现直接耐晒翠蓝GL染锦纶具有较高的耐光色牢度,同时其它色牢度良好.     

偶氮染料结构与日晒牢度关系研究

本文介绍了近年来国内外对于偶氮染料光致褪色的研究进展,综述了偶氮染料光褪色与偶氮键断裂机理。利用Hammett方程,反映出取代基效应与染料褪色速率间的定量关系,并将Hammett方程引入分散、酸性偶氮染料日晒牢度的分析中,很好的阐释了取代基团吸、供电子效应对染料在不同纤维上日晒牢度的影响,并提出了获得优异日晒牢度染料的合成和应用方法。     

The Relation between Light Fastness of Colorants and their Particle Size

Published evidence relating the rate of fading of a colorant to its physical state in the substrate, and to the photochemical layer effect, is discussed, and a new theoretical Model of light fading is proposed. In this the rate of oxygen diffusion from the atmosphere is considered, first in traversing the polymeric substrate, and then in entering an embedded colorant particle, under illumination. Expressions are derived which show that the rate of fading should vary with I/a² (a = radius of particle), for large particles. As the particles become smaller, the rate tends towards a 1/a dependence, and eventually, with very small particles, it is independent of their size. Recently reported rates of fading of pigments of measured particle size gave results in agreement with the present treatment; the smallest particles thus considered are of the same order of magnitude as those of high light fastness direct dyes in cellulose, as observed by electron microscopy. Thus the model may be applicable to at least some water-soluble dyes as well as pigments.     

国内外涂料耐候性和耐光性试验方式浅谈

简述了国内外常用的自然气候老化试验和人工加速老化试验方法，并比较了氙弧辐射加速老化试验和紫外照射加速老化试验。