| The washing of textiles is a very complicated process.The process is related to the formula of detergent,washing condition(hardness of water,washing temperature,washing time),the composition of stain,mechanical force,the chemical structure and surface properties of textile.However,there are few researches about the influence of textile property on the washing performance.Our study focuses on the effect of fabric structure and fabric finishing on the washing performance.Our aim is to provide the rules of stain removal for textiles with different properties,and to explore the key factors affecting the washing effect through surface hydrophobicity and zeta potential analysis.Finally,the washing effect of mainstream washing products in the market was evaluated.Firstly,the effect of different textile structures(plain and twill weave,woven and knit fabric,pure cotton and polyester/cotton and cotton/spandex fabric,cotton and polyester and silk fabric)on washing performance was studied.Soiled fabrics printed with grass,coffee milk,sebum and chili sauce stains were washed under the same washing condition,and the detergency was calculated using the L~*,a~*and b~*values of stains before and after washing.The results show that the detergency of cotton plain fabric is higher than cotton twill fabric because of its smooth and tight surface.The detergency of oily stains on cotton knit fabric is higher than cotton woven fabric because of its lower hydrophilicity and looped structure.Besides,the detergency of hydrophobic stains on cotton fabric with synthetic fiber component is lower than that of pure cotton fabric.Furthermore,it is difficult to remove protein stains such as grass stains from pure silk fabrics and remove hydrophobic stains from pure polyester fabrics due to the strong interaction between stain and fabrics.Secondly,the stain removal capability of fabrics with different finishing methods(water-repellent finishing,softening finishing,wrinkle resistant finishing and antistatic finishing fabric)was investigated during home-laundry.The influences of surface energy and surface zeta-potential on washing effect were studied.The results show that the detergency of stains is relevant to the surface energy of fabric.When cotton fabrics were treated with water-repellent,softening and wrinkle resistant finishing agents,the fabrics become more hydrophobic,the detergency of oily stains such as sebum and chili sauce stains decreases.However,it is easier for oily stains to get away from polyester knit fabrics treated with antistatic finishing.Coffee and milk stains can be removed effectively,so the change of detergency is not obvious.The detergency of grass stains is not very relevant to the fabric surface energy.Besides,the surface-zeta potentials of fabrics and stains also affect the stain removal capability during home-laundry.Furthermore,the detergency of cotton knit fabrics without fluorescence whitening is better than that of fluorescence whitening ones.Fluorescence whitening finishing has little influence on the detergency of polyester knit fabrics.Lastly,four different detergents were evaluated to confirm the above obtained stain removal rules.The physical and chemical properties of different detergents were tested by fluorescence spectrophotometer and surface tensiometer.The effect of fluorescent whitening agent(FWA)in detergents on fabric washing effect was studied by testing under two test light sources,100%UV(UV include)and 0%UV(UV exclude).The results show that the detergency is mainly determined by surface energy for different detergents.The detergency and whiteness of the cotton fabrics washed by detergents containing FWA is significantly better than that of fabrics washed by detergents without FWA if the test was carried out under UV light source.And the value of detergency and whiteness retention become higher with increasing amount of FWA in the detergents.While FWA in the detergents has little effect on the detergency value of polyester fabrics. |
PDF Full Text Request