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Certain aspects of the handle of fabric laminates are related to properties of the component fabrics. Particular attention is paid to a theoretical prediction of the bending stiffness of a laminate from the bending and tensile properties of its components. This theoretical stiffness is a minimum value; if, in practice, the observed stiffness is much greater than this, it may generally be assumed that excess of adhesive or of melted foam is the cause. The paper also reports work on other features of the bending behaviour, such as the degree of recovery from bending, and on the shearing behaviour. The work is concluded by a brief study of some faulty laminates. [ABSTRACT FROM AUTHOR] more...

A method for measuring the variance between ultra-short lengths of yarn is presented and shows that the reported flattening of the B(L) curve to a constant value in the 5(0) region does not occur at lengths of down to at least 0-1 cm. The curve continues to rise logarithmically as the length decreases, possibly as far as 0· 045 cm, though detection imperfections render readings at this length open to some doubt. Yarn irregularity is shown to be strongly dependent on fibre length and on yarn fineness, particularly at short test lengths, and the possibility of periodicities at less than 1-cm ‘wavelengths’ is shown to exist. [ABSTRACT FROM AUTHOR] more...

A letter to the editor is presented about the measurement of the mean diameter of a blend of wool fibers through using the mean diameter of each component of the blend.

Part I of this series dealt with the relation between the subjective stiffness and liveliness of a fabric and its measured bending parameters. In the present paper, the possibility of using comparisons with smoothness standards in the assessment of fabric smoothness is examined, and the applicability of a purely objective measure of fabric smoothness, based on surface air-leakage, is also investigated. [ABSTRACT FROM AUTHOR] more...

Previous papers have described the use of the cloth-bending-hysteresis test in investigating the detailed bending behaviour of fabrics. An account is given in this paper of the use of the techniques of regression analysis to investigate the correlation between the results of this test and other mechanical tests with subjective assessments of cloth stiffness and liveliness for two groups of fabrics. The correlations are shown to be highly significant, and good estimates of these two subjective properties could be made from the laboratory tests. [ABSTRACT FROM AUTHOR] more...

An account is given of an investigation in which air-flow measurements of fineness were made on individual core samples drawn from lots of scoured wool. From analyses of variance, estimates were made of between-bales, between-ends, and between-cores components of variance. These estimates suggest that the sampling precision (95 % confidence level) for lots of ten bales or more should be, at the worst, ±0-2 µm and may be better than ±0-1 µm for a sample consisting of two cores from each bale. An example is given in which the variability of fineness within a lot of greasy wool is compared with the variability within the same lot after it had been scoured and rebaled. [ABSTRACT FROM AUTHOR] more...

The increasing volume of yield-testing of greasy wool indicates the need for equipment that has a greater rate of handling samples and is more automatic than that employed in methods in current use. New washer equipment has been developed in which samples are washed by being dispersed and circulated around a long pipe by a special pump; the arrangement ensures thorough treatment of the whole sample and facilitates complete collection after washing. Released dirt is removed continuously from the system during washing. After being washed, the sample is discharged directly into a can, dewatered by suction, and dried in the same can by forced convection of hot air. Experimental prototypes have been built and have been extensively tested in a commercial testing laboratory. When the washer is used in a conventional yield-testing arrangement with one operator, samples can be handled at a rate of 20 samples/hr, and the total time required to process a sample to obtain a washing-yield value is about 25 min. It is intended that the rate of testing will be 30 samples/hr when the equipment is used as a section of a Wool-base Analyser. [ABSTRACT FROM AUTHOR] more...

Treatments designed to increase and decrease friction were applied to rayon staple fibre before processing, as card web, and after needling. Basic frictional properties of the fibres were examined. The first two groups were processed into needled fabrics, and it is shown that considerable damage occurs with high-friction fibres: this results in a deterioration in mechanical properties. Even a wet process without additive causes some loss of strength. However, treatment with a high-friction additive after needling results in increased strength in the fabric. [ABSTRACT FROM AUTHOR] more...

A survey is presented of measurements of the variability of yield, vegetable-matter content, and fineness between core samples within growers' or auction lots representing a variety of types of wool from the Australian clip. The pattern can be represented, in part, by a linear relationship between the within-bale standard deviation of a particular characteristic and the mean value of that characteristic for the lot. The data presented do not suggest that a change from the present sampling schedule is necessary. [ABSTRACT FROM AUTHOR] more...

A comparison is reported of fineness results obtained for 27 lots of scoured wool by the projection-microscope and air-flow methods. The sampling of the scoured wool was done by core-boring, and the cores were hand-carded before air-flow tests were made. The sub-samples for projection-microscope measurement were cut into snippets 1 mm long in order to obtain a length-biassed sample. The air-flow apparatus was calibrated with reference tops in five different forms. The results show that there exists a systematic difference between the air-flow and projection-microscope mean diameters of scoured wool when the air-flow instrument is calibrated with reference tops in the original state. A better agreement results by hand-carding the test samples of the reference tops, but the closest agreement is obtained by cutting, washing, and hand-carding these test samples so that their condition is similar to that of the core sample being tested. Provided that this kind of calibration were applied, the mean diameter of washed wool could be determined by air-flow testing of cored and hand-carded samples. [ABSTRACT FROM AUTHOR] more...

Eight methods of determining the coefficient of variation of yarns or slivers when only a limited amount of material is available are discussed. The basic method involves direct measurement and calculation, and each of the other methods is compared with this one, which tends to be somewhat lengthy, for a range of man-made-fibre yams spun on the cotton system. A method based on the use of the cumulative-frequency distribution is shown to be quite the most accurate of the seven methods investigated and has the merit that it can be performed comparatively rapidly. [ABSTRACT FROM AUTHOR] more...

A letter to the editor is presented about a research paper entitled "A Diffraction Method for the Estimation of Average Diameter and Standard Deviation of Diameter in a Fibre Sample," by I. R. Edmonds. more...

Differences between the results obtained for the fineness of wool tops measured by air-flow and projection-microscope methods can arise because the coefficient of variation of the measured top is different from that of the tops used to calibrate the air-flow meter. The validity of some assumptions implicit in the air-flow calibration is examined and a correction table for precise use of the air-flow meter calculated. The corrections range from ♂2% at 16 µm to zero at 36µm. [ABSTRACT FROM AUTHOR] more...

IWTO Core-test Regulations define the core sample that must be taken for yield measurement on a lot of greasy wool. On the basis of studies of fineness variability between and within bales, the expected sampling precision for mean fineness is calculated on the assumption that the same sample is used as a source of test specimens to be measured by a proposed modification of the air-flow-fineness method. Under present regulations, the expected precision is acceptable; it is emphasized, however, that, if core samples are to serve a dual purpose, variability of both yield and fineness must be considered in drawing up sampling schedules. [ABSTRACT FROM AUTHOR] more...

A letter to the editor is presented about the irregularity of roving during the production of fabrics.