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Sultonov Shavkat Abdullayevich, Amonov Muxtor Raxmatovich, Bukhara State University E-mail: [email protected]
THE STUDY OF THE RHEOLOGICAL PROPERTIES OF THE THICKENING POLYMER COMPOSITIONS AND INK-BASE PRINTING
Abstract: The article describes the research results about the dependence of the viscosity of the concentration system of bentonite and it was found that bentonite K-4: HAE = 1 : 0.05 : 0.2 provides stable structures with the required dynamic viscosity in case of having optimal components. The influence of the concentration of the alkaline agent and the holdup time of the active dyes on the degree of fixation was revealed during the research. Along with this it was found that the degree of fixation of active dyes when printing using a thickener has not been reduced and in contrast it was higher by 10-25% than when using existing thickeners. The structural-mechanical and rheological properties of the developed polymer systems were carefully studied and revealed a deeper penetration of printing inks into the fabric, compared with printed inks thickened with sodium alginate.
Keywords: Viscosity, concentration, bentonite, degree of fixation, thickener, component, packing, porosity, polymer composition, rheological properties.
The urgency of the issue. Significant progress Therefore, the actuality and timeliness of re-
has been made in the artistic and coloristic design of search is quite obvious as it aims at creating tech-
textile materials, and printed textiles are becoming nologies which usenatural compounds as textile-
more and more essential all over the world, and the auxiliary substances not causing any danger for both
competition in the field of textile printing is taking biosphere and humankind. Bentonite, K-4 (on the
on a global scale. basis of acrylates) and hydrolyze acryl emulsion
In these conditions, the basic problem of the (HAE)can be easily implemented for thickening
domestic textile industry has been the increase in printing inks, as they are produced in our Repub-
the competitiveness of its products, the solution of lic, inexistent and relatively inexpensive. In spite of
which requires not only improving the quality of tex- these advantages, they are not widely used at present
tile materials, but also reducing production costs, as in domestic factories.
well as providing ecological requirements in accor- Thereby, it seems quite justified and expedient to
dance with world standards. develop new thickening compositions on the bases
In the converters all over the world, pigments and of natural and synthetic polymers, as the usage of
active dyes are mainly utilized for printing cellulose- high-quality, inexpensive and effective thickening
containing textile materials. In both cases, the effective- compositions in printing is an important link in the
ness ofthe printing process depends to a large extent on chain of activities to ensure competitiveness and re-
the correct choice ofthe thickener, which is manifested duction of the cost of textile products.
as a printed figure and printed fabrics in the economic To assess the effect of the sort and concentra-
and environmental aspects of the production. tion of the polymer on the properties of the re-
suiting systems, the dependence of the viscosity dynamic viscosity and good stability of the struc-
of the composition (n) on the concentration of ture provide the composition with the component
bentonite(C) was studied. It was found that the ratio: bentonite: K-4: HAE = 1: 0.05: 0.2, which is
most low-concentrated systems with the necessary clearly visible from (Fig. 1).
Figure1. Dependence of viscosity of compositions on concentration and sort of polymer
The main task with the use of active dyes is to ensure the highest possible degree ofdye fixation. The implementation of the produced low concentrated clots, especially on the basis ofbentonite, K-4 and HAE, create favorable conditions for this: first, by eliminating the side reaction of the dye with the polymer; secondly, due to a very permeable and thin film of printing ink, providing a more complete exit of the dye from it.
However, the noted positive factors may not be so significant if the optimal alkalinity of the ink is not ensured during its preparation, storage and in conditions of dye fixation. Due to the fact that the hydrogen index of the developed gelatinous and porous thickeners has a value of 10.0 ± 5, studies have been carried out to determine the effect of the concentration of the alkaline agent in the printing ink on the degree of dye fixation (DDF). The corresponding data for the dye is given in turquoise 4KP in (Fig. 2). from which it can be seen that when using the produced porous thickener, the concentration of sodium hydrogencarbonate should be about 15 g/kg. Similar dependences were obtained for other dyes as well.
When the ink is stored with a sufficiently high alkalinity (pH = 10), hydrolysis of the active dye can occur. In order to detect the effect of the storage time of the printing ink on the degree of hydrolysis of the active dye, one printing ink was used for printing immediately after its preparation and after 1, 2 and 24 hours.
It was found that the degree of fixation of active dyes during printing with the use of the developed bunch as a freshly prepared substance and after keeping it for a day did not decrease and but in the contrary it was by 10-25% higher than when using sodium alginate (Fig. 3), which can show the absence ofhydro-lysis. In addition, it should be noted that printing with a paint kept for an hour, provided a rise in the intensity of color. Presumably, this can be caused by the partial settling of bentonite included in the composition.
Next, we studied the dependence of the yield point of a thickener and ink, the degree of fixation of the dye by the fabric after printing, and the relative intensity of the color from the ratio of the constituent components of the thickening printing ink.
Figure 2. Dependence of the degree of fixation of active dyes active turquoise KP from concentration of alkali agent
Figure 3. Dependence of the degree of usage of
Figure 4 shows a smooth course and the absence of minima on the yield strength (Pm) curves and the composition of the mixture, which indicates that the components of the thickening systems are well compatible, regardless of their ratio in the mixture (curve 2) and regardless of the additives of the ink components (curve 3). The presence of good compatibility is also confirmed by the high stability and uniformity of the mixtures obtained.
A smooth transition is also observed on the curves of the change in the colouristic indices of the printing of the composition substances shown
the active turquoise 4KP from the holdup time in (Figures 5 and 6). From these graphs it can be observed that compositional thickenings, promoting a higher degree of fixation (Figure 5, curve 1), provide a lower color intensity.
It is of no less importance that the study of the structural-mechanical and rheological properties ofthe composition based on the synthesized oligomer in order to assess the possibility of its use in printing tissue.
The results obtained indicate a deeper penetration of printing inks thickened by the polymer composition into the interior of the tissue, compared to printing inks thickened with sodium alginate.
Figure 4. Dependence of the yield point of the thickener and the printing ink on the ratio of K-4 and HAE: 1 -thickeners on the basis of K-4; 2 - thickeners based on HAE; 3 - thickening on the basis of K-4 and HAE. 4 - printing ink
Figure 5. Dependence of the degree of fixation of the dye with tissue after printing: 1 - printing inks with a polymer composition; 2 - printing inks based on bentonite
Cbentonite,
Figure 6. Dependence of the color change of the relative color intensity on the concentration of bentonite: 1 - Composition based on K-4; 2 - Composition based on HAE; 3 - Composition based on K-4 and HAE; 4 - Printing ink
It can be seen from Figures 5 and 6 that the relative content of bentonite, K-4 and HAE in the substance increases, the depth of penetration into the tissue and the degree of fixation of the dye increase. The addition of bentonite to the printed composite blobs promotes the production of sharper printing loops. Finally, the mixtures of bentonite-K-4-HAE and printing inks in question show an improvement in the rheological
properties evaluated by the shape of the rheological curve.
Thus, it has been found that polymer compositions based on rice starch, bentonite-K-4-HAE, can be successfully applied as thickeners of paints for printing fabrics by compositions that helps to reduce the breakage, and also increases the degree of fixation of printing ink as compared to printing inks, thickened with sodium alginate.
References:
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2. Nekrasova V. N., Shcheglova T. L., Belokurov O. A. // Technology of textile industry. 2010 - No. 2.-P. 50-53.
3. Melnikov B. N., Kirillova M. N., Moryganov A. P. Current state and prospects for the development of dyeing technologies of textile products.- M.: Light and Food Industry, 1983.- 232 p.
4. Breitman V. M., Senakhov A. V Investigation of the influence of interaction between dyes and thickeners in printing inks fixed by a cloth during printing // Technology of textile industry. 1970.- No. 4.- P. 100-104.
