Publication Sponsored by the Society's Scarce Resources Committee-II

The Scarce Resources Committee welcomes any comments readers of this paper wish to make. These should be addressed to Mr M. Roberts, The Technical and Education Officer, The Society of Dyers & Colourists, PO Box 244, Perkin House, 82 Grattan Road, Bradford, West Yorkshire BD1 2JB. The price of oil has risen by approximately 70% in 1979 giving greater need to conserve energy. This paper demonstrates that savings of 30% can easily be made in relation to stenters. The basic thinking behind the work could be applied to other processes.     

Publication Sponsored by the Society's Scarce Resources Committee — IV

This paper attempts to summarize the cost areas related to the operation of a modern stenter and suggests ways of improving efficiency that can be introduced by the practical finisher. For them to be implemented it is essential that adequate instrumentation 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.     

Publication Sponsored by the Society's Fastness Tests Co–ordinating Committee – XLIV

Specific application of BSI recommendations for testing new test methods is illustrated quantitatively for an interlaboratory trial of a new colour–fastness test (colour fastness to chlorination: sodium dichloroiso–cyanurate). Statistical analyses of the results quantify repeatabilities and reproducibilities.     

Publication Sponsored by the Society's Fastness Tests Co–ordinating Committee –XLVI

The precision of Grey–Scale assessment of change in colour is estimated. Allowance was made for any interlaboratory differences, prior to assessment, in carrying out a colour–fastness test, using the prescribed test method, to obtain the specimens. The results show how the assessment precision depends on the Grey–Scale rating. The practical laboratory component of obtaining the tested specimens almost always has better precision than the subsequent assessment. The particular test method used to obtain the specimens can therefore be regarded as having satisfactory precision in practical application. Taking the mean of three assessors results in better precision than that from a single assessment. Assessment precision appears consistent when compared with appropriately transformed older data.     

Publications Sponsored by the Society's Fastness Tests Co-ordinating Committee-XXXV

The need to test carpets for colour fastness to various agencies, viz. acid. alkali, heat, light, reducing agents, salt shampoos, urine, and water, was examined critically. It was decided that tests were required for assessing the colour fastness of carpets to salt, shampooing, and water. Details of these tests were published by the Society in July 1966 (I).     

Publication Sponsored by the Society's Colour Measurement Committee — XIV The Impact of Modern Lighting on the Dyer

Until recently, the two desirable characteristics of high lamp efficacy and good colour rendering were mutually exclusive in fluorescent lamps but in 1971 calculations were made which showed that they could co-exist if the emitted light approached a 3-line spectral power distribution (SPD), ideally the emission bands being at 450, 540 and 610 nm. The discovery of new phosphors has made such lamps a practical possibility and two manufacturers have marketed lamps whose SPDs lie between the continuous SPD of conventional lamps and the 3-line ideal. Such lamps have been found to render many objects more colourful than any conventional lamps and thus more acceptable to the average observer. This combination of desirable characteristics suggests that such lamps may become the most common form of artificial lighting, especially in view of the need to conserve fossil fuels. Tire installation of one of these lamps in a large department store, however, caused some serious problems with textiles which were metameric matches. These may be more serious with sources whose SPDs are closer to the 3-line ideal. The same problems will also occur with nontextile materials, e.g. ceramics and plastics, which match under various conventional sources. These developments in lighting may make extensive re-matching necessary.     

Publication Sponsored by the Society's Fastness Tests Co-ordinating Committee - XLII A New Chlorination Fastness Test for Wool

The new test is based on sodium dichloroisocyanurate. Its essential features and the practical reasons for them are outlined. Ten laboratories tested nine dyeings twice, and each result was assessed twice by six assessors. Two of the laboratories also included samples of the dyeings in bulk processing. The results showed that the new test is sufficiently precise and realistic.     

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.     

Publication Sponsored by the Society's Scarce Resources Committee – III Potential Energy Savings in Dyeing and Finishing

In its Industrial Energy Thrift Scheme, the Department of Industry is publishing a series of reports on energy use and conservation in the different sectors of the manufacturing industry. Report No. 20*, ‘Energy Use in the Textile Finishing Sector’, published in August 1980, is based on work carried out under the scheme by Shirley Institute. Although the Report is readily available from the Department at Ashdown House, 123 Victoria Street, London, SW1E 6RB, and it is necessary to read the full account to get the maximum benefit, the Society's Scarce Resources Committee felt that an extended summary should be prepared and published in the Journal.     

Publications Sponsored by the Society's Identification of Dyes Committee—VII

The reactive systems in several newer types of reactive dyes are discussed briefly. Dyeings or prints of selected dyes in each range on cotton have been subjected to various tests designed to distinguish between the different chemical classes and to place them in their correct position in Clayton's Tables.     

Publications Sponsored by the Society's Identification of Dyes Committee—IX

The reactive systems and chromogens present in further types of reactive dyes are briefly discussed. Dyeings or prints on cotton of selected dyes in each range, including more black reactive dyes, have been tested to distinguish between the various types of reactive dyes. Tests for detecting the presence of metals in reactive dyeings are included.     

Publication Sponsored by ETAD The Adsorption of Dyes on Activated Sludge

Effluents from textile dyeing and printing processes usually contain dissolved or suspended dyes in small quantities. One of the treatments which may be applied to such effluent is passage through a biological treatment plant in which colour removal proceeds via adsorption on activated sludge. An indication was sought as to the likely efficacy of such a plant in dealing with intermittent influxes of dyes at concentrations similar to those to be expected in practice. A simple test method is described which enables the tendency of a dye to be removed by adsorption on activated sludge to be categorized. Application of the test to six classes of dyes by some of the member firms of ETAD has indicated that the adsorption depends on the class of dye and to structural differences within the classes.     

Publications Sponsored by the Colour Measurement Committee-VI

A set of gloss-paint samples exhibiting large (10–25 CIE units) colour differences has been prepared. Visual assessments have been made under different viewing conditions. The results substantiate the view that visual assessments vary markedly with the size of sample and, together with earlier work (2), show that assessments also vary with the size of the colour difference. Thus, colour-difference equations can correlate well with visual assessments only for given conditions. Existing equations apply best to conditions very different from those encountered in industry. It should not be too difficult to develop a more suitable equation for industrial use, given sufficient experimental data obtained under appropriate viewing conditions.     

Ecological Aspects of Water Usage in the Textile Industry

From cave drawings and from records preserved on clay tablets, the history of man's use of textiles can be traced back to well before the birth of Christ. Obviously the quantities per head of population required for clothing and other purposes were then minute compared with those of today, and their production and processing was unlikely to have caused any ecological problems. When considering that over the last thousand years alone the world's population has increased more than tenfold, and in that time, the demand for clothing has grown out of all proportion, it can be seen that the process is bound to have left its mark.