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Quality in Raw Material Purchasing - A New Approach
Purchasing by specification
Many companies were not using specifications and did not communicate well with their suppliers. Numerous problems were noted of handling unworkable materials and of producing unserviceable garments. The properties of raw material affect not only its handling characteristics during production, but also the quality of final product as well.
Thus if there is to be any continuity in production and product quality from lot to lot, and style to style, there must be some assurance that little or no change takes place in raw material properties. This can be guaranteed only by establishing a rigid set of practical specification.
Once specification has been established, there is no reason to restrict their use to vendor and purchaser. They can also enhance the communications between the designer and the selector, between local management and quality inspectors, and between fabric producer and fabric finisher, trims suppliers.
The four ingredients of a fabric specification:
1. Physical characteristics: Details should be stated about fibres, yarns, material construction, finishing treatment, finished width and acceptable tolerances.
2. Performance characteristics: All important characteristics need to be specified, together with tolerances. Typical areas are shrinkage, colourfastness to light, washing, laundering, rubbing etc, strength, care characteristics, flame retardants features.
3. Visual defects: The grading system to be used should be specified, together with the level of acceptance.
Ex: 4-Point system, 10-Point system.
4. Shade specification: The colors of the purchased materials should be specified, together with tolerances between batches and pieces and within pieces.
The raw material specification sheet provides an effective means of communication; it should never be made the exclusive channel of information flow. Companies who are implementing a policy of continual improvement are seeking to promote long term relationships with reliable suppliers, and are recognizing the need for direct communication at managerial level. This suggests the need for vendor rating and for clear policies on communication in the context of quality assurance. However, the fashion business is dynamic and every season sees new combination of cloth and trims. The selection, inspection and testing of materials has to be done very carefully.
Common Fabric Defect and Testing
Automated Fabric Inspection
Fabric inspection has proven to be one of the most difficult of all textile processes to automate. It has taken decades for computer and scanning technology to develop to the extent that practical, consistent and reasonably user-friendly systems could be produced.
Today's automated fabric inspection systems are based on adaptive, neural networks. They can learn. So instead of going through complex programming routines, the users are able to simply scan a short length of good quality fabric to show the inspection system what to expect. This coupled with specialized computer processors that have the computing power of several hundred Pentium chips makes these systems viable.
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