EFFECT OF MICROWAVE ASSISTED ENZYMATIC PRETREATMENTS ON REACTIVE DYEINGS OF COTTON KNITTED FABRICS

Abstract

Microwave energy is an alternative method for pre-treatments, dyeing and finishing of textile materials. It is fast, uniform, effective and energy efficient heating. Using enzymes for pre-treatment of cotton fabrics have also many advantages over conventional processes such as reducing the chemical damage to the fabric, energy saving and short process times. Nowadays, with the increase in importance of cleaner production techniques, sustainability and carbon footprint for the textile industry microwave-assisted enzymatic pre-treatment is became an important topic.In this research study, the effect of microwave-assisted pre-treatments with pectinase, cellulase and laccase enzymes on dyeability of cotton knitted fabric was investigated. Therefore, cotton knitted fabrics were pre-treated with sodium hydroxide, pectinase, cellulase and laccase enzymes by conventional and microwave-assisted methods. All fabrics were conventionally dyed with reactive dye after pre-treatments. Hydrophilicity, contact angle, whiteness/yellowness indexes of conventionally and microwave-assisted pre-treated fabrics were measured and compared with the conventionally treated samples with sodium hydroxide. The absorbency of the all pre-treated samples were checked in accordance with AATCC 79-2007 Method, and the wetting time was found to be less than 60 seconds. Whiteness and yellowness results were adequate for dark-coloured (dyeing or printing) fabrics. The dyed cotton knitted fabrics after different pre-treatments were examined for colorimetric measurement results and dry-wet rubbing/ colour staining-colour change washing fastness properties. The fabrics were dyed successfully with C.I.Reactive Black 5 (Remazol Black B [Dystar]. Microwave-assisted pre-treated fabric samples with sodium hydroxide, pectinase and cellulase enzymes were dyed dark colours. Pre-treated fabric samples were dyed more dark colours than microwave-assisted pre-treated fabric samples. The pilling test results (4+) and colour fastness to dry-wet rubbing (4-5 +) / colour staining-colour change washing (4-5 +) of the dyed fabric samples were investigated and adequate results were obtained. The time saving was almost 90 % by microwave heating. In the light of these results, it is clear that microwave-assisted pre-treatment process can be an important alternative to conventional pre-treatment method. In addition short processing times were contributed to sustainability and reduction of carbon footprint. Mikrodalga enerjisi tekstil materyallerinin ön işlem, boyama ve bitim işlemleri için alternatif bir metottur. Hızlı, uniform, etkili ve ısıtma enerjisi verimlidir. Pamuklu kumaşların ön işlemlerinde enzimlerin kullanımı da konvansiyonel yöntemler ile karşılaştırıldığında kumaşta daha az hasar, enerjiden tasarruf ve kısa işlem süreleri gibi birçok avantaja sahiptir. Günümüzde, tekstil endüstrisinde temiz üretim tekniklerinin öneminin artması ile mikrodalga enerjisi yardımı ile enzimatik ön işlemlerin gerçekleştirilmesi önemli bir konu haline gelmiştir. Bu çalışmada, pektinaz, selülaz ve lakkaz enzimleri ile mikrodalga enerjisi yardımıyla ön işlemlerin pamuklu örme kumaşların boyanmasına etkisi araştırılmıştır. Konvansiyonel olarak ve mikrodalga enerjisi yardımı ile ön işlem gören kumaşların hidrofilite, temas açısı ve beyazlık/sarılık indeksleri ölçülmüş ve sodyum hidroksit ile konvansiyonel olarak işlem gören örnekler ile karşılaştırılmıştır. Farklı ön işlemlere tabi tutulduktan sonra boyanan pamuklu örme kumaşların renk ve haslık özellikleri incelenmiştir. Kumaşlar C.I.Reactive Black 5 ile başarılı şekilde boyanmıştır. Boncuklanma test sonuçları ve sürtünmeye/yıkamaya karşı renk haslık test sonuçları kabul edilebilir değerlerde bulunmuştur. Ön işlemde mikrodalga enerjisinin kullanımı işlem sürelerinde yaklaşık % 90 oranında tasarruf sağlamıştır.