Blind dyeing means dyeing with the systems only, It is an exacting service in terms of quality and speedy delivery. Implementation of blind dyeing need the attitude to get success. It is as like to visualise colour management with folded eyes .
To get the result through blind dyeing we need not a super trained or experience staff and worker. The benefits of achieving right-first-time (RFT) production through blind dyeing are documented and include cost savings, increase in productivity with on time processing and a timely response to customer requirements. These benefits would not have been possible without the fulfillment of optimized laboratory requirements and would result in improved, controlled and systematic dye application techniques. A complete change in philosophy and management attitudes is required to the dyeing techniques. Similarity, many technical factors require tight control. Here we will discuss on blind dyeing as well as RFT technique, particularly blind dyeing principle and its concept of success, laboratory requirements for bulk reproduction, main controlling points for blind dyeing .
Introduction
The wet processing sector of the textile industry has traditionally suffered from low levels of Right-First- Time (RFT) production. Dye houses today need to recognize the increasing need to adopt a more scientific approach. The pursuit of quality assurance systems and the introduction of total quality management (TQM) can accept no other concept than RFT. Blind dyeing has been viewed as the unattainable goal for colorists in much the same way as like the ‘zero defect’ concept. But the need for service and quality, while keeping costs down, will only be achieved in this way.
2. PRINCIPLE OF BLIND DYEING
The technique of blind dyeing not only means that no additions are made, but also requires that the shade should not even be checked until the process is complete. There must be confidence in the way the process is set out and controlled, so that an RFT result is the only possibility. The motivation for introducing a blind dyeing operation is three fold: service, cost and quality.
2.1 Service factor
Meeting the customers’ requirements is the main thrust of industry today. Fixed delivery dates, fast response, correct shade are just some of these requirements. These will only be achieved by carefully planned RFT operation. Due to re-processing the cycle time is increased and thus there is a delay; there is a production loss and also loss of capacity utilization. Blind dyeing lends itself to fixed dyeing times, therefore predetermined machine capacities allow production to be accurately planned and quoted delivery schedules met.
2.2 Cost factor
Profit margin can only be achieved in one of the following three ways:
(i) Increasing the selling price, (ii) Decreasing the cost price, or (iii) Both.
Moreover, failure costs money. It is obvious that a successful blind dyeing
process has a cost advantage. Customers are now better informed and aware of
their rights to get the best value for their money. This emphasizes the need to
reduce costs and ensure timely delivery besides reduce wastes and environmental
pollution.
TABLE 1
RELATIVE COST AND PROCESSING TIME OF CORRECTION
Stage | Polyester | Cotton | |||
Cost | Time | Cost | Time | ||
Shading | 18% | 50% | 20% | 22% |
|
Re-dyeing | 80% | 135% | 100% | 200% |
So in the area of dyeing, RFT is the only answer to achieve the needs
emphasized. Higher the success rate of RFT, greater is the possibility of
reducing costs.
3. “RIGHT-FIRST-TIME” PRODUCTION
The rate of production of the required shade, at the required levels of fastness, dimensional stability and tensile strength to levels which would satisfy the highest retail specifications of end consumer, that is achieved without any further adjustment or re-working in the process. Suppose, a drop in production efficiency of only 10% would mean a “RFT” rate of 90% (extremely creditable) ; but this would obviously mean 10% of the production batches would need some form of repair or shading addition.
80% RFT is not uncommon in a modern dye house. An improvement in RFT level from 80% to 90% would allow for an increased production capacity of 50%.