Title of Invention

"A process of preparing print textile material"

Abstract

This invention relates to a process of preparing print paste to print the textile material comprising: preparing stock paste by dissolving 1-4.5 parts of thickener composition as claimed in our co-pending application no. 2347/Del/97, in water containing 0.4-0.6 parts of liquor ammonia and 10-15 parts of binder as herein described and remaining water to form 100 parts of stock paste, mixing with the said stock paste in 1-6 parts of pigment paste and a fixer 0.7-1.5 parts as herein described, to form the print paste.

Full Text

This invention relates to a process of preparing print paste. BACKGROUND Pigment printing is a well known and an established art in the area of printing of textile materials. For printing purpose, a print paste which contains a high viscosity paste as thickening medium, binder, pigment and fixing agent is applied on the fabric through the screen either manually or by a printing machine. The print is then fixed on the fabric by first drying i.e. evaporating the volatiles and then curing at elevated temperature. Conventionally, pigment printing is done using- a thickening medium consisting of kerosene - water emulsions (KE system). In such a system kerosene constitutes almost 75 to 80% (by weight) of the total paste. During drying and curing process, all the kerosene is driven into the atmosphere. It is not only the loss of the.precious kerosene but also creates serious air pollution. Because of pollution problem, no developed country is using kerosene -emulsion thickening system in pigment printing" now-a-days. Alternative to KE system is the synthetic thickening system which essentially contains a high molecular weight polycarboxyiic acid as its ammonium salt. Four to five such synthetic thickener systems of well known company of the world are commercially available in the present market. But none of these products give-prints equivalent to prints obtained with kerosene - emulsion system in every respect. The object of the present invention is to prepare a print paste using the environmental friendly thickener compositions in aqueous medium. To achieve the said objective, this invention provides a process of preparing print paste for printing textile material comprising: preparing stock paste by dissolving 1-4.5 parts of thickener composition as herein described, in water containing 0.4-0.6 parts of liquor ammonia and 10-15 parts of binder as herein described and remaining water to form 100 parts of stock paste, mixing with the said stock paste in 1-6 parts of pigment paste and a fixer 0.7-1.5 parts as herein described, to form the print paste. The biner used is a compatible binder. The fixer used is a compatible one used for pigment printing. The said print paste is having pH in the range 6-8. DETAILED DESCRIPTION The preparation of the Thickener Composition is disclosed in our copending application no. 2347/Del/1997. Depending upon the amount of liquid part used in preparing the composition, the product may be in its free flowing powder form or as thick pasty mass. This formulated product was used for making the print paste. Before making the print paste, a stock paste was prepared. For preparation of the stock paste, 1.0 gm to 4.5 gm of the thickener composition was dispersed in water and required amount of ammonia for complete neutralization of the product was added to it under vigorous stirring condition. 10-15 parts of binder per 100 parts of the total stock paste was then added and the paste was stirred thoroughly. Binders are commercially available acrylic based emulsion containing nearly 40% solid material. Appropriate amount of pigment usually 1-6 parts/100 parts of stock paste and a fixer was then added to the stock paste and mixed thoroughly with mechanical stirrer. A fixing agent is typically a resineous product with active functionality capable of being formation of a crosslinked structure in the drying and curing stage of the print. It is also commercially available in solution form in aqueous medium. The amount of fixer added in the print paste was between 0.7 to 1.5 parts per 100 parts of the stock paste. Printing was carried out manually with the print paste using a suitable screen on cellulosic fabric. Immediately after printing, the fabric was dried in an air circulated oven set at 105°C followed by curing for 5 minutes at 150°C temperature. Following tests were then carried out on the printed fabric and compared the results with the data obtained from similar test of the printed fabrics which are printed using standard Kerosene emulsion system under identical conditions. Testing of Properties of Printed Fabric for Evaluation of the Thickener FASTNESS PROPERTIES Rubbing fastness — In this test method, printed fabrics were rubbed with dry rubbing cloth and also with wet rubbing cloth. The staining on the rubbing cloth after rubbing was then assessed with gray scale. (IS-766,1988) Washing Fastness This test method was designed for the determination of colour fastness of the printed fabric to the action of soap and sodium carbonate solution at 95°C alongwith the beating~Iction of steel balls. A specimen of the fabric to be tested in contact with specified adjacent fabric was mechanically anitated in a soaD soda solution, rinsed and dried. The change in colour of the fabric under test and the staining of the adjacent fabric were assessed with gray scale (IS-765, 1979). Scrubbing Fastness — In this test method, a sample of fabric was dipped in hot soap solution containing sodium carbonate and scrubbed in wet condition with a nylon bristle brush. The specimen was then rinsed and dried. The change in colour of the specimen was assessed with gray scale for change in colour by comparing with that of original unscrubbed sample (IS-11908, 1986). COLOUR STRENGTH AND COLOUR DIFFERENCE These two properties were mathematically determined by measuring percentage reflectance from the printed fabric with respect to a standard print. Print with kerosene emulsion system was used as standard and colour strength and the difference of the samples were determined with respect to it. ACS-1400 (spectra sensor li) instrument system was used for measurement of these parameters. STIFFNESS PROPERTIES Stiffness property was determined by measuring the bending length of 6" x 1" rectangular printed fabric and using the process as described in ASTM D-1388-64. The foilowing examples illustrate the preparation of print pastes, their use in printing and the results of performance study. The embodiments in the examples are for the purpose of illustration but not exhaustive and hence variations apart from the examples given below are possible in the light of the above disclosure. The invention will now be described with reference to the examples. EXAMPLE I A stock paste was prepared using the following ingredients Thickener composition* 02.0 parts Water 87.5 parts , Liquor ammonia 0.5 parts Binder 10.0 parts (HicrylSK4530 CD. Corporation,Mumbai) 100.0 parts Prepared by the method as described in Example 1 of our copending application No. 2347/Del/ 97 These ingredients were added one after another in a 200 ml polypropylene container as per sequence given above and mixed thoroughly using a high speed stirrer (rpm 300-3000). In order to make the print paste, 4 parts of a red pigment (Imperon RED KC GR from Colour Chem.India) was then added to 100 parts stock paste and stirred thoroughly 1 part fixer per 100 parts stock paste (fixer CCL from Colour Chem.) was added and mixed thoroughly before printing. EXAMPLE II Following the same process as described in Example I, another print paste was prepared with following ingredients. Thickener composition* 03.5 Water 86.0 Liquor Ammonia 0.5 Binder 10.0 (HicrylSK4530C.D. Corp.,Mumbai) 100.0 parts * Prepared by the method as described in Example 7 of our copending application No. 2347/Del/97 EXAMPLE III Print pastes were prepared following the method described in example I using thickener compositions containing different base polymers (described in our copending application No.2347/Del/97 example I), compositions of which are given in Table I. The print paste viscosities were within the range 30,000 cps to 40,000 cps. Printing was carried out on cotton poplin using screen printing with all the print pastes as well as a standard KE system for the sake of comparison. Results of the print performance studv are shown in Table I. It was found that increasing amount of styrene content decreases colour strength and increases stiffness properties. These results also show that acrylamide in the composition with less styrene improves scrubbing, colour strength and softness of the print. TABLE I (Table Removed) * BA - Butyl Acrylate. St - Styrene, MAA - Methacrylic Acid AAM-- Acrylamide, MBA - N. N -Methylene-bis-acrylamide EXAMPLE IV Print pastes were prepared with thickener composition containing different base polymers (described m our copending application No2347/Del/97Example II) compositions of which are given in Table II. Similar process was adopted for making the print pastes and also for printing as described in Examples I & III respectively. Print performance data (Table II) show that the products are in the acceptable range. It was observed that increase in acrylic acid content in the composition helps in reducing the stiffness of the print. TABLE II (Table Removed) AA - Acrylic Acid; for other monomers Please see foot note of Table I. EXAMPLE V Prints were taken from the print pastes of thickener compositions containing different base polymers, compositions of which are shown in table III. print paste preparations and printing were carried out as per process described in example I & III above. Results of print performance data are shown in Table III. Polymer containing vinyl acetate possibly results comparatively soft film and hence the print obtained with it was slightly inferior compared to others with respect to rubbing and scrubbing fastness properties and the prints are less stiff also. TABLE III (Table Removed) AMA - Allyl methacrylate, DVB - divinyi benzene, VA - Vinyl acetate for others please see foot note of Table I EXAMPLE VI Printing at Mill Print paste was prepared using 50 kg of stock paste prepared from the nondusting formulated product.(Thickener composition of example I in our copending appliction No. 2347/Del/97) and following the process as described in Example I. Print paste viscosity was 33,000 cps. Printing was carried, out with Rotary Printing Machine on 300 meter fabric. Colour strength was found to be 20% higher compared to the prints, the mill was normally producing with the imported thickener system. The print was also having softer feel compared to its counterpart in the mill. We claim: 1. A process of preparing print paste to print the textile material comprising: preparing stock paste by dissolving 1-4.5 parts of thickener composition as herein described, in water containing 0.4-0.6 parts of liquor ammonia and 10-15 parts of binder as herein described and remaining water to form 100 parts of stock paste, mixing with the said stock paste in 1-6 parts of pigment paste and a fixer 0.7-1.5 parts as herein described, to form the print paste. 2. A process of preparing print paste as claimed in claim 1 wherein said binder is acrylic based emulsion containing 40% solid material. 3. A process of preparing print paste as claimed in claim 1 wherein the said stock paste is having pH in the range 6-8. 4. A process of preparing print paste substantially as herein described with reference to the forgoing examples

Documents:

2345-del-1997-abstract.pdf

2345-del-1997-claims.pdf

2345-del-1997-correspondence-others.pdf

2345-del-1997-correspondence-po.pdf

2345-del-1997-description (complete).pdf

2345-del-1997-form-1.pdf

2345-del-1997-form-19.pdf

2345-del-1997-form-2.pdf

2345-del-1997-form-3.pdf

2345-del-1997-pa.pdf

2345-del-1997-petition-others.pdf