Browsing by Subject "color fastness"

The aim of the study was to deepen the knowledge of the possibilities of using natural dyes for printing of cellulose fibres. There has been little research on the topic and in these studies colour fastnesses have not reached the same level as with protein fibres. However, recent international studies provide encouraging results of dyeing cellulose fibres with natural dyes. Based on this research the aim was to develop an optimum printing paste recipe for cellulose fibres. The study compares how different mordants and auxiliaries affect the colour fastness of cotton and linen printed with Cortinarius semisanguineus and onion. The study also compares differences between pre-mordanting and in-paste mordanting. The experimental part of the study consisted of making the printing pastes, the pretreatments, printing and post-treatments of the fabrics and colour fastness testing. There were ten different types of printing paste recipes which were carried out with both dye materials. The mordants used were alum and tannin. The printing pastes were made acid with acetic acid or alkaline with soda ash. Pastes without any auxiliaries were also made. The thickening agent used in all of the pastes was Gum Tragacanth. The colour fastnesses of printed fabrics were tested to laundering, daylight and rubbing. The results showed that it is possible to achieve good washability and abrasion resistance properties when printing on cotton and linen with natural dyes. The test samples' fastness to light seemed quite weak though. The best fastness to laundering belonged to samples which were mordanted with tannin. It was notable however, that the Cortinarius semisanguineus gave best washing fastness results in acidic printing pastes as onion gave the best result in alkaline paste. There were no significant differences between the fastnesses of the pre-mordanted and in-paste mordanted samples.