Cashmere Processor Requirements
The Processing of Cashmere
The most important aspect of processing cashmere from any source is the ability to dehair the raw material, thus removing the coarse guard hair fibres to produce down fibres virtually free of hair.
Traditionally, Australian cashmere has been sold as raw cashmere into the world market, and Australian growers through the Australian Cashmere Growers Association, and the Australian Cashmere Marketing Corporation, have presented to the world stage superb clip presentation and high quality control in the classing of Australian cashmere.
Cashmere buyers fall into various categories whereby the end product may be simply, dehaired cashmere, woollen or worsted yarns, cashmere blend yarns, woven or worsted fabrics or classic cashmere sweaters and high fashion garments.
Regardless of the end use, the raw product is of significant importance in the chain of events for any buyer, with quality first and quantity second.
Standards set over many years by Dawson International still stand today for processing cashmere, and the greatest demand in the world market is for white cashmere with fineness and length.
Value adding in the first instance from raw cashmere to dehaired cashmere has opened up many new markets in China, Mongolia, USA and Iran. For the smaller niche marketplace, New Zealand and Australia have established their own dehairing facilities.
Processor companies such as Dawson International. Luyan Dawson (a joint venture partner of King Deer Cashmere Company of Baotou Inner Mongolia, China ) Forte (USA) and several Italian and European companies, carry out their own scouring and dehairing, as well as sourcing both raw and dehaired cashmere from agents and grower organisations. Purchasers have an eye on the end result, to ensure that the processing will produce an acceptable, and indeed expensive, value for money product. Thus purchasing by standard, objective measurement is absolutely essential. That is by, fibre diameter and range, fibre length and range, colour, vegetable content, and weathered or damaged fibre tips (which can be a problem if the guard hair is shorter than the down).
In the marketplace it is absolutely imperative that product standards are maintained, since there are many companies who will always be able to supply a cheaper "cashmere" product, but of inferior quality,
Lowering cashmere’s image in the marketplace.
Australian and New Zealand cashmere has proved "different" to Chinese cashmere, with a micron range of 15 to 18 microns, compared with 14.5 to 15.5 micron Chinese cashmere. However, research has demonstrated that the handle of 17micron Australian cashmere can be compared with that of 15.5 micron Chinese, providing the micron of the fibre is uniform.
Creating a niche market, simply to handle 100% Australian or Australasian cashmere, is a very expensive operation; with processors being in the dark as to the world market reaction to them. In the woollen system, a minimum quantity of 50 tonnes of dehaired fibre is required to market a separate line on the world stage, requiring an input of around 200 tonnes of raw cashmere. Whilst supply remains at currently low levels, the Australian cashmere industry requires "clever" creative ideas and a sound marketing scheme to create a "niche market" for export of a "unique cashmere" product.
The diameter range is very important in the processing and in the handle of the finished product. A fairly tight histogram indicates that the diameter of the fleece is uniformly consistent, and this makes the best yarn. The suggested range for cashmere down with a mean of 15 microns, is 8-24 microns, while for18 microns, the range is 12-28 microns. The standard deviation and coefficient of variation are two measures used to describe the spread of distribution. These terms are important to the breeder when assessing the distribution of the fibre he is producing.
The important point with distribution is that it must have a distinct cut-off. The distribution should be symmetrical so that it is a mirror-image of itself on each side of the mean. Problems during processing occur when the distribution of the down fibres is not succinct, but tends to "tail-off" towards the fibres with greater diameter. No matter what the mean diameter, the processors require fibre with a minimum of fibres over 27 microns.
Most of the problems with fibre distribution have been experienced in white crossbred fibre, Breeders need to identify the goats producing fibres which fall in the 28-40 micron range. They may be either coarse down, or in some cases, fine guard hair. While both present problems during processing, the fine guard hair is highly undesirable and impossible to remove. It is also important that none of the down fibres are modulated. When modulated fibres occur in this diameter range, they are most likely fine guard hairs.
Superior length is likely to be one of the high quality features of cashmere produced in the Southern Hemisphere. The ideal mean length for woollen spun processing is 50-55 mm, but 40-42mm is acceptable. Lengths up to 70mm can be handled on the woollen system, but longer than that would be used for worsted processing. Most processors require the average lenth of the fibre to exceed 35mm.
The crucial factor with length is that there are no fibres shorter than 15mm, as these fibres will pill in the finished product, or reduce the yield when they are removed during carding.
The ideal length range for worsted spinning is 70mm, but no shorter than 20mm or longer than 110mm. For processors wanting to spin on the worsted system more emphasis on length is needed in specifications when buying cashmere, whether it be de-haired and or in the raw state.
When the guard hair is longer than the down it gives a greater protection to the cashmere down and stops it weathering at the tips. In burry country, guard hair also helps to reduce vegetable contamination. If the hair content in the fleece is reduced too much, it is possible that the animal could compensate by producing more grease. Increased grease content may also be the precursor to problems with flies in goats, destroying one of their great "easy-care" attributes. Protruding down also looses yield through breakage of the weathered tips during processing.
It is important that the guard hair is significantly coarser than the down. Recommendations have always been for the guard hair to be four times the diameter of the cashmere to enable ease of dehairing, with a mean diameter greater than 60 microns. In summary, the guard hair should be longer and significantly coarser than the down.
One of the early findings within the Australian cashmere industry has been that the lustre of Australian cashmere is greater than that of traditional suppliers. The lustre of both Australian and New Zealand cashmere enhances the handle of the product, but it does not make the cashmere slippery or shiny as in the case of mohair.
This is the single most important characteristic of cashmere. Probably most of the features that have been discussed contribute to the handle, including diameter, diameter profile, length and range of length, protruding scale structure and possible protection by the guard hair. Handle is difficult to assess in a non dehaired fleece. When assessing handle in a mixed fleece of hair and down beware of the improvement in total handle resulting from finer guard hair – this can be very misleading.
The final yield of cashmere down from raw fleece covers many aspects of the term "yield". Removal of any dirt and dust from any initial willowing, removal of any contamination, removal of excess guard hair, scouring and final dehairing all have an effect on the final yield of down. The down is also graded while dehairing, and this provides a true yield figure in terms of the quantity of useable cashmere recovered.
Classing standards are therefore most important with the preliminary sorting of raw cashmere on the basis of colour, micron and length.
Yields of anything under 15% should be kept out of sale lines.
Foreign matter in the fleece should be avoided. This includes parasites (eg. Lice or lice-egg casings) vegetable matter (eg. Trefoil burr) and skin fragments. Heavily cotted fleece, which has become contaminated with vegetable matter, should not be mixed with clean lines.
During processing, all of these properties are important to the way in which the fibre behaves. Every time the fibre is sensitised, stress is placed on the fibre, eg. There is heat damage during scouring and drying. Each process increases the degradation of the product, and some properties will be changed. To use cashmere commercially it is important that there is total removal of guard hair. In cashmere that is difficult to dehair, increased stress is placed on the fibre in order to effect this removal, either by increasing the time taken for the cashmere to pass through the machinery, or the number of passages the fleece undergoes during dehairing.
The histogram becomes broader during the dehairing process. The finer fibres break more readily than the coarse fibres, and thus an increased number are obtained at a finer diameter. It is essential when comparing diameter histograms to also examine the length of the cashmere.
The cashmere may also be changed during the combing process. Combing produces a "top" and a "noil". In cashmere processing a minimum quantity of noil is desirable as cashmere is difficult to felt. Combing removes the shorter fibres thereby increasing the average length. It also increases the fibre diameter. Raw fibre, which has been difficult to dehair and has undergone breakage of the finer fibres, will loose these shorter fibres during combing. Difficulties during processing increase the cost and decrease the profitability of the product.
The ease of dehairing depends on a number of factors:
Over the centuries there has always been a demand for cashmere. It has always been considered a luxury item, and even in an ever changing world, with greater production, and new innovative usage of luxury fibres, 100% cashmere is considered the ultimate in luxury fibre.
Australian cashmere growers have a fantastic market potential with, increasing affluence world-wide. Although a young industry, it forms part of the overall goat industry in Australia. With cashmeres being a multi-purpose goat, the benefits of growing cashmere fleece are accompanied by their benefits as meat goats and weed controllers, offering great potential for the future of the Australian cashmere industry.© 2000 A.C.G.A.