In order to maintain its premium in the world cotton market it will be important for Australia

to extend its position as a preferred supplier of high quality fibre. Australian cotton is

currently used by spinners for the production of medium-fine yarns, i.e. in the Ne 30 to 40

count range, although efforts are afoot to extend the spinning range of Australian cotton to

Ne 50 and 60. Currently it is not easy for spinners to accurately estimate key yarn quality

parameters, e.g. yarn evenness and tenacity, in order to estimate the additional value to them

of purchasing cottons with incrementally higher fibre quality.This project has tackled the scientific challenge of predicting the key parameters of interest to

the spinning mill manager from fibre quality measurements. The output of the project is a

user friendly software package that can be used by spinners to predict the effects on their

production of using higher (or lower) quality cotton. The software is potentially an important

tool for marketing high quality Australian cotton fibre. For example, it could be used to

illustrate quantitatively to a spinner the technical benefits of utilising a new variety of finer,

longer cotton, e.g. Sicala 340BRF.Cotton fibre maturity and fineness (linear density) are two important fibre characteristics

affecting cotton yarn quality and spinning performance. CSIRO, in partnership with the

CRDC and the Cotton CRC, has developed two new instruments, namely Cottonscan and

SiroMat for quick and yet accurate measurements of the two fibre properties1. Another

outcome of this project is the incorporation of linear density and maturity measurements into

the Cottonspec prediction model. It is noted their inclusion the Cottonspec models,

particularly of linear density, is solely on the basis of the additional predictive ability they

give to any yarn quality prediction model.Work on this project has occurred in four stages. They have been:

1. Liaison with and collection of industrial spinning data from three leading Chinese cotton

spinning mills,

2. Development of a robust mechanistic and statistical model to predict ring spun yarn

quality,

3. Validation of the model using Australian cotton and industrial spinning mill data and

4. Incorporation of the prediction models and data into software that can be used by mill and

QC managers.

Further validation of the models and software is required before a commercial and release-tomarket

plan can be developed for the Cottonspec program. To this end a new project in

which the current Cottonspec will be tested in five to six overseas (Chinese) mills has

commenced.

There are currently no stand-alone, commercial yarn quality prediction programs available

largely because modelling of yarn quality has largely centred on purely statistical models that

fail in their ability to be applied widely because they overlook the mechanical associations

between fibres in a yarn that affect final yarn quality. Cottonspec overcomes the limitations

associated with statistical modelling by incorporating the rules of yarn mechanics in the

model.

The closest commercial system to the Cottonspec is Cotton Inc.'s Engineered Fibre Selection

(EFS) system. The EFS system is a software package used to manage USDA High Volume

Instrument (HVI) data and allow optimisation of bale inventory in terms of yarn and processquality. The short comings of the EFS system are that it doesn’t predict yarn quality and it does not allow for non-USA cotton to be used. Moreover, EFS considers only HVI-measured

fibre properties. As many mills use a combination of growths and data to control their

laydowns these limitations make the EFS system largely redundant in the day-to-day

operation of large spinning mills.

However, aside from these limitations, the EFS system does provide a tool for spinners to

manage the average quality (as described by HVI) of their lay-downs and in doing so allows

some indirect prediction of yarn quality to be arrived at. The provision and control of the

average fibre properties in bale lay-downs allows spinners to better appreciate the

consequences of using particular quality cotton in their processing. From this perspective

EFS adds value to the use of US cotton by creating the perception that the spinner buying US

cotton is in partnership with the US cotton grower.