The STARFISH Research Project

Origins of the Project The question of how to improve the reliability and the performance of cotton knits - particularly in respect of laundering shrinkage - was the driving force behind the research that led to the development of the STARFISH fabric engineering software and the new concepts that lie behind STARFISH Technology.

Origins of the Project In the late 1970’s and early 1980’s three important trends arose in the European market. k Increased demand for cotton knits in outerwear. k Widespread adoption of domestic tumble dryers with consequent higher shrinkage of garments made from knitted fabrics. k Demands from large retailers for better shrinkage performance.

Industry Response The industry responded to the challenge by developing machinery and techniques to improve shrinkage performance. Adjusting the weight by changing yarn count and stitch length resulted in a change of width, which also was not acceptable. But a reduction in shrinkage was accompanied by an increase in area weight, which the retailers would not accept.

Need for a New Approach A lot of time, money, and resources were being expended in trial-and-error fabric development on behalf of powerful retailers. It was obvious that a new system of fabric development and quality control was needed. But the results were not always acceptable and the retailers were always demanding better and better performance.

International Institute for Cotton At that time, the International Institute for Cotton was working on behalf of cotton users in Europe. After some preliminary work, the STARFISH project was launched in 1978, under the leadership of Allan Heap. IIC became interested in the market potential for cotton knits in outerwear and realised that the problems of product development and product reliability had to be solved scientifically.

Initial Data Collection The project began with systematic data collection on Interlock, 1x1 rib, and plain single jersey fabrics. Analysis of the data yielded some important conclusions. Large quantities of fabrics were knitted and finished - full scale in several factories in Europe and the USA - using a wide range of yarn counts and stitch lengths, and different wet processing routes.

First Conclusions Important results from the first trials. k The important effect of wet processing. k The inadequacy of current (K-factor) theories. k The key concept of “Reference Dimensions”. k The STARFISH Reference Equations.

Reference Dimensions Knitted fabric dimensions are difficult to measure consistently and reproducibly because they are always more or less distorted. For STARFISH, “fully relaxed” means after five wash and tumble laundry cycles. The most useful and reliable way to properly characterise a knitted fabric is to measure it in its fully relaxed condition - with all distortions removed. This is the STARFISH Reference State.

The STARFISH Reference State In this way, the influence of different manufacturing and processing variables upon fabric dimensions can be discovered. When they are in their Reference State, different fabric qualities can be reliably characterised and compared. Distortion is what makes fabrics shrink. This knowledge is the essential basis for fabric engineering.

Effect of Wet Processing The Reference Dimensions of commercially bleached and dyed fabrics are different from those of the corresponding greige fabrics. all previous work reported in the literature, based on greige samples or laboratory processing is of very little practical value for making fabric engineering calculations. Different wet processing routes have different (greater or lesser) effects. Therefore...

Inadequacy of K-factor Theory The only mathematical theory available at that time for making fabric engineering calculations was the so-called K-factor theory. Detailed analysis of the STARFISH database showed these equations to be inadequate, since they take no account of the yarn properties or the wet process. Courses / cm = K c / Loop length Wales / cm = K w / Loop length

STARFISH Reference Equations Mathematical analysis of the STARFISH database leads to a set of equations that can be used to calculate the Reference Dimensions of any fabric that lies within the scope of the database. Once we can calculate the Reference Dimensions, then it is easy to determine, e.g. the weight and width that correspond to given levels of shrinkage. This knowledge can then be used to improve the efficiency and reliability of fabric development and quality control operations.

STARFISH Computer Program Fabric engineering calculations were facilitated by building the STARFISH Reference Equations into a computer program, for in-house use, in The program allowed a large number of alternative fabric qualities to be evaluated within a short time, without any expenditure on materials or production resources. Fabric development had been transformed from a trial and error black art into an engineering discipline.

During the 1980’s The database was broadened and deepened to include additional fabric types, yarn types and processing - including mercerising and resin finishes. The STARFISH Reference Equations were also refined and developed, so that they became more powerful and capable of self-calibration. After extensive evaluation by means of industrial case studies, the first commercial version of the STARFISH software (Version 4) was released in 1988.

Cotton Technology International The International Institute for Cotton was disbanded in 1990, due to a failure among the politicians of member nations to agree adequate future financing. Cotton Technology International was formed in 1991 by Allan Heap and Jill Stevens to acquire the assets of the IIC Technical Division and pursue further development of STARFISH Technology. Research & development continues: STARFISH Version 5 was released in 1992, Version 6 in 1997, Version 6.5 in 2002.

STARFISH Version 6.5 The faster, cheaper, more reliable way of doing product development.