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Fibre Measurement


Blankenburg, G., Philippen, H., Spiegelmacher, P. & Hahnen, J.,

Correlation of the Fibre Ellipticity, Snippet Length and Embedding Medium with the Mean Diameter of Mohair and Wool.,

IWTO, Nice, Dec 1992.

The ellipticity of 6 Interwoolabs and 8 IMA mohair tops are measured, and the results used to explain differences between wool and mohair calibrations, and the snippet length effect in wool calibrations. 6 Refs.


Edmunds, A.R.,

Effects of Snippet Length on Profile Fibre Diameter Measurements,

IWTO, Nice, Dec 1992

Provides a theoretical discussion on the interaction of ellipticity and snippet length on projected image techniques such as projection microscope and OFDA.. Graphs are included showing the measured mean diameter and standard deviation on OFDA measurements of 10 tops with snippet lengths ranging from 0.2 to 5mm. 9 Refs.


Baxter, B.P.,

Influences on Comparisons between the Mean Fibre Diameter of Wool measured by Airflow and by Projected Image Methods,

IWTO, Istanbul, May 1993.

Summarises the large volume of work on biases between Airflow and projected image techniques. Covers areas such as specific gravity, crimp, ellipticity, coefficient of variation, calibration errors, grease, fibre length, preparation effects, relaxation, medullation (lambs wool) and nutritional deficiencies. 57 Refs.


Teasdale, D.C.,

A Technical note on the Bias in Diameter Coefficient of Variation caused by using the average Diameter of Fibre Snippets,

IWTO, Istanbul, May 1993


Liu, Y. and Baxter, B.P.,

Current Advanced Technologies in Raw Wool Testing,

First China International Wool Conference, Xi'an, P. R. China, Apr. 1994


Blankenburg, G., Henning, H.J., Spiegelmacher, P., Philippen, H,

Influence of Snippet Length on the Micro projection Diameter Values,

IWTO, New Delhi, Apr. 1994.

Provides a history of trials of the effect of snippet length on projection microscope measurement of fibre diameter, and presents the results of a new international trial on the snippet length effect. 13 Refs.


Edmunds, A.R.,

Effects of Standard Deviation on Airflow Measurements of Mean Fibre Diameter,

IWTO, Nice, Nov. 1993.

Linear regressions of the standard deviation vs the mean are calculated for all the Interwoollabs calibration wool tops since 1959 and for 228 N.Z. wools. Deviations from these line have important consequences for the use of airflow. 11 Refs.


Butler K., Dolling M.,

Relating Mean and CV% of Fibre Diameter to Spinning Fineness,

Technical Release, Victorian Institute of Animal Science, Sneydes Rd, Werribee, Victoria, Australia.

Describes the concept of spinning fineness, and the formulae used to calculate it. 6 Refs.


Hunter L., Gee, E., Braun A.L.

The Effect of Steam or Wet Relaxation on Airflow Wool Fibre Diameter Measurements,

South African Wool and Textile Research Technical Report No. 403. 1978.

Describes an experiment on airflow results on tops that were measured normally and then steamed or soaked in water and re-measured. The wetted (relaxed) tops were found to measure broader on the airflow by up to 0.8um. 2 Refs.


Smuts S., Hunter L., Gee, E.

The Effect of Medullation and Coefficient of Variation of Diameter on the Airflow Measured Diameter of Mohair, South African Wool and Textile Research Technical Report No. 560.

An experiment involving 83 mohair lots was carried out to determine the effect of medullation and CV of diameter on airflow measured diameter. Medullation was found to have no apparent effect but CV was found to have a significant effect although at about half the level of theoretical predictions. 26 Refs.


Swan, P.G.

Fibre Specification and Staple Structure,

CSIRO Division of Wool Technology, WoolSpec 94 Report, Sydney, Nov 1994.

Describes the relationship between the wool staple and the fibres within. Presents experimental data that shows resistance to compression can be predicted from fibre diameter and curvature. Also, a strong positive correlation was found between measured fibre curvature (PM) and staple crimp frequency, and a negative correlation between standard deviation of curvature and staple crimp definition. 26 Refs.


Nissen-Wooller B., Baird K., Marler J.W.,

Mean Fibre Diameter Measurement of Coarse Tops using the Projection Microscope Method - Comparison of Two Snippet Lengths,

IWTO, Nice, Dec 1994.

Reports the results of an interlaboratory trial which compares the PM measurement of 0.8mm snippet length to PM measurement of 2mm snippet length. A statistically significant average decrease of 0.67um was found when the snippet length was increased from 0.8mm to 2mm at the average top diameter of 36.5um, however, the between laboratory component of variance increased at the same time. 13 Refs.


Baxter B.P.,

Some Observations on the 1993 Snippet Length Effect - Projection Microscope Round Trial.

IWTO Paper 4, Nice, 1994.

Suggests that fibre curvature measurements on the OFDA, together with the results of the round trial, lend support to the theory proposed by Edmunds (B2). 13 Refs.


Hunter L.,Smuts S., Dorfling L.

The Characterisation and Measurement of Objectionable Medullated Fibres in Wool and Mohair Using Image Analysis.

IWTO Special Topics Group, Appendix 4, Capetown April 1996.

Describes work at the CSIR Division of Textile Technology in South Africa to measure medullation in mohair and its effect on dyeing. Experimental results based on measurement of diameter and medulla diameter ratio on Cape Mohair and carpet wools are reported. 19 Refs.


Naylor G.R.S., Phillips D.G

Skin Comfort of Wool Fabrics.

IWTO Technology and Standards Committee, Report 7, Boston, May 1997.

Skin comfort was measured for a range of single jersey fabrics made from worsted spun yarn of either wool or acrylic fibres. Relative comfort can be predicted from the density of coarse fibre ends per unit area of fabric, with the percentage of fibre ends greater than 32um being the key factor. 6 Refs.


Lindsay A.R., Marler J.W.

The Importance of the Coefficient of Variation of Fibre Diameter of Blends of Wool Tops when Measured by Airflow, Laserscan and OFDA.

IWTO Technology and Standards Committee, Report 13, Boston, May 1997.

The measured fibre diameter of blends of wool top was investigated using airflow, Laserscan and OFDA. It was found that if the individual components of the blend differed by more than 10um, the airflow could be in error by up to 4um. Concludes that large differences between airflow and projection microscope techniques may be due to excessively high coefficient of variation of diameter in the sample. 9 Refs.


Sommerville P.J.

The Effect of between Fibre Coefficient of Variation on the Fibre Fineness Measured by the Airflow.

IWTO Technology and Standards Committee, Report 14, Boston, May 1997.

The development of the theory of the airflow instrument is described, and an experiment is conducted using airflow, Laserscan and OFDA to confirm the theoretical predictions of the effect of coefficient of variation of diameter on the estimates of fineness obtained by airflow. 14 Refs.


Somerville P.J.

Measurement of the Fineness of Superfine Wool: A comparison of Airflow, Laserscan and OFDA.

IWTO Technology and Standards Committee, Report 15, Boston, May 1997.

In a study of the measurements of mean fibre diameter of fleece samples from superfine sheep, using Airflow, Laserscan and OFDA, significant diameter dependent differences were found between the instruments. Below 16um, OFDA is registering a greater number of fine fibres than Laserscan. 12 Refs.

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