A comparison of the effect of the mechanical wash action on textile fabric deterioration and soil removal efficiency

[摘要] ENGLISH ABSTRACT:Washing and cleansing in an aqueous washing solution is a complex process involving theinteraction of numerous physical and chemical processes. Investigations indicate thatvarious factors present during repeated laundering might have an adverse effect on textilefabrics. Little is known, however, about the effect of the different mechanical wash actionson the deterioration of textiles.The automatic washing machines commonly used in South African households are oftenbroadly classified as top loaders and front loaders. On closer inspection, however, itbecomes clear that marked differences exist between the horizontal drum machines (H),vertical drum agitator type (V(A)) and vertical drum impeller type machines (V(/)). The effectof laundering on the wear life of textile fabrics has been extensively investigated, but aserious need for research on the effect of the different mechanical washing actions of thedifferent washing machines on textile fabrics exists on both national and international level. Anumber of factors have an effect on textile deterioration during washing, e.g. number ofwashes, temperature of wash liquid, detergent type as well as fabric finishes and waterquality. Fabric properties like changes in tensile strength, print deterioration and fraying, aswell as electron microscope photographs, were used as indicators of mechanicaldeterioration to textiles.The broad aim of this exploratory study was firstly, to compare the effect of repeated washingin different domestic automatic washing machines (commonly used in South Africa) on thepossible mechanical damage to textile fabrics and, secondly, to compare the soil removalefficiency of the mechanical wash actions of the different machines. An experimental studywas therefore decided on. The washing of the test fabrics, as well as the testing, was carriedout under controlled conditions in a laboratory. Apart from the different mechanical washactions of the individual machines, the effect of the variables wash temperature, level ofdetergent and number of washes, was also investigated. This was done by measuringtensile strength, print deterioration and fraying propensity on samples laundered repeatedlyat 40°C or 60°C, with and without detergent in the washing liquid, and comparing the colourchange measured on laboratory-soiled test fabrics after washing.Analysis of the mechanical wash actions of the seven washing machines compared in thisstudy indicated conspicuous differences among machines. It can be concluded that themechanical wash action in the category V(A) machines is the most severe, and causes thehighest reduction in tensile strength, the greatest print deterioration and the highest degreeof fraying. These machines did not, however, exhibit greater soil removal efficiency than theother two categories of washing machines. The machines from category H did not exhibit asignificantly different soil removal efficiency than those from category V(A), but theirmechanical wash action proved to be less severe. Category V(/) machines seem to have themost delicate wash action and will probably cause the slightest fabric deterioration over thelong term, but unfortunately produces poor soil removal efficiency results. This study alsoconfirmed that washing fabrics in water alone causes more deterioration of tensile strength infabrics than washing with detergent in the wash solution.Due to the limited scope and exploratory nature of this research/study, certain aspects ofautomatic washing machine processes could not be tested empirically. Recommendationsfor future research and implications for consumers were formulated.

[发布机构] Stellenbosch University