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Purpose Pretreatment of fabric with a number of chemicals and auxiliaries is a prerequisite for inkjet printing. Owing to the rapidly increasing use of inkjet printing for textile fabrics, the study of the effects of process variables on various characteristics of the resulting print has drawn considerable interest recently. The purpose of this paper is to study the effects of different variables associated with the inkjet printing process on the quality of the resulting print. Specifically, the effects of chemicals and auxiliaries used in the pretreatment of the fabric prior to printing and factors such as steaming time were studies. Design/methodology/approach In the present study, which forms a part of a larger study by the authors, the influence of the nature of thickener, the amounts of thickener, urea and alkali, pH of the pretreatment liquor and the duration of steaming on ink penetration into the printed fabrics and the ink spreading across the fabrics was studied. The nature of ink penetration and ink spreading are known to have pronounced effects on the quality and, in turn, the overall appearance of the resulting print. A set of experiments based on a blocked 25–1 fractional factorial design with four centre points were conducted to evaluate the role of the aforementioned five variables. Ink penetration was quantified on the basis of the principles of Kebulka-Munk theory while ink spreading was analysed by image analysis. Findings Detailed statistical analyses of the experimental data obtained show that different thickeners perform differently and can have a marked influence on ink penetration and ink spreading. In the case of polyacrylic acid-based thickener, changing the levels of the factors has a marked effect on ink penetration and in-turn on ink spreading. In the case of polyacrylamide (PAM)-based thickener, on the other hand, the effect of changing the levels of various factors on the ink penetration and ink spreading is considerably less pronounced. In addition, PAM treated samples exhibited better performance in terms of ink penetration and spreading. Originality/value This study provides useful information for textile printers and highlights the importance of selecting the right type of thickener to make the printing process and the quality of the resulting print more predictable and controllable.

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In this research work, a nondestructive technique of image analysis was explored to determine the fibre orientation and void content in Bagasse fibre reinforced composites. Fibre length, alkali treatment and fibre loading were studied as variables. The fibre orientation was irrespective of the fibre length, fibre loading and alkali treatment variables. The void content and size decreased with increases in fibre length and alkali treatment. The alkali treatment resulted in the removal of lignin, making the surface of the fibres rough. It also led to making the fibre count fine i.e. reducing the diameter of the fibres and thus presenting more fibres for interaction with resin. Both these phenomena resulted in a slower flow of resin. The void content of bagasse fibre composites decreased with higher fibre loading because a higher number of fibres slows the resin flow. However, the size i.e. area of the voids increased with the fibre loading from 20 to 30%, probably due to increased wetting difficulty.

The present study relates to manufacturing, characterization and optimization of bagasse fiber reinforced composites. For this purpose, response surface methodology was applied to simultaneously optimize the tensile strength, tensile modulus and tensile strain of bagasse fiber reinforced composites. Three levels of process variables, including concentration of sodium hydroxide for bagasse fiber treatment (4, 6, and 8%), content of bagasse fiber (10, 20, and 30 wt%), and length of bagasse fiber (1, 2, and 3 inch) were used to design the experiments according to the Box–Behnken design. Experimental results were analyzed by analysis of variance and fitted to second order polynomial models by using multiple regression analysis. The Derringer’s desirability function revealed that the values of process variables leading to optimized tensile strength, tensile modulus and tensile strain are 4%, 14.2 wt% and 1 inch for concentration of NaOH for bagasse fiber treatment, content of bagasse fiber and length of bagasse fiber, respectively. Validation experiments were carried out and high degree of correlation was found between the actual values and the predicted values of tensile properties of bagasse fiber reinforced composites.