AIM:-To dye cotwool, cotton, woollen thread with malachite green.APPARATUS REQUIRED:-1. 500ml beakers.2. tripod stand. 3. wire gauge.4. glass rod. 5. spatula.6. Cotwool. 7. woollen thread.8. cotton materials.CHEMICALS REQUIRED:-1. Sodium carbonate, 2. tannic acid, 3. malachite green dye.

Tannic acid solution

Malachite green

PROCEDURE:-1. Preparation of sodium carbonate solution: About 5.0g of solid sodium carbonate is taken and dissolved in 250ml of water.2. Preparation of tannic acid solution: 100ml of water is taken in a beaker and about 0.1g of tannic acid solution is added to it . Solution is heated . On heating a clear solution of tannic acid is obtained.3. Preparation of dye solution: About 0.1g of malachite green is taken and added to 400ml of water . On heating a clear solution of tannic acid is obtained.4. Dyeing of cotwool and wool: About 200ml of dye solution is taken and cotwool and woollen thread is dipped in it to be dyed . Solution is boiled for about 2 minutes. After that the cloth is removed and washed with hot water 3-4 times , squeezed and kept for drying.5. Dyeing of cotton: Cotton does not absorb malachite green readily , therefore it requires the use of mordant . For dyeing a cotton cloth we dip it in sodium carbonate solution for 10 minutes and then rinse it with water. Then put the cloth in hot tannic acid solution for about 5 minutes .Now the cloth from tannic acid solution is taken out and kept in tartaremetic solution for about 5 minutes . The cloth is removed and squeezed with spatula to remove most of the solution . Now we place the cloth in boiling solution of the dye for about 2 minutes . Dyed cloth is removed and washed thoroughly with water , squeezed and kept for drying.

Observation:-1. The colour of the wool cloth dyed directly by dipping in hot solution of malachite green dye is fast.2. The colour of the cotton cloth dyed directly (without using mordant) by dipping into hot solution of malachite green is not fast to washing and is of low intensity.3. The colour of the cotton cloth dyed indirectly by using mordant and then by dipping in hot solution of malachite green is fast to washing and is of high intensity.

Dying of Fabrics

Sumit Jana Dying of fabrics. A report on an investigatory project in chemistry in partial fulfilment of AISSCE-2016.

Submitted by:- Sumit Jana Class: - XII.AISSCE Roll no:-

Under the supervision of D.A.V. Model SchoolI.I.T. Kharagpur. 1

Certificate

This is to certify that the project entitled Dying of Fabrics is a bonafied record of work carried out by Sumit Jana & Swastik Kumar Behra, class XII AISSCE Roll no :- _______________ under my supervision and guidance.

________________________________ ______________________________ (Susmita Panigrahi) (N.K Gupta) Chemistry teacher Principal

______________________________External examiner

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Acknowledgement

I would like to express my sincerest thanks and deep sense of gratitude to my chemistry teacher Mrs. Sushmita Panigrahi. She has always been helpful to me and also acted as my project guide with her able guidance throughout the duration of my project work despite her busy schedule. She was always there for me whenever I needed her help.

Then I would like to thank our Principal Mr. M.P SharmaFor he had provided us with all the necessary materials we needed to complete this project.

Finally I would like to thank my parents and my friends without whom I would not been able to complete my project.

D.A.V Model School I.I.T. Kharagpur. Sumit JanaDate:- IntroductionDyes are coloured substances which can adhere to the surface of the materials and are used to give colour to paper, food-stuffs and various textiles such as cotton, wool synthetic fibres, silk etc. Chemically a dye contains:(i) Some group (such azo, indigo, triphenylmethyl, anthraquinone, etc.) which is responsible for the colour of the dye.(ii) Some group (such as ---NH2, ---SO3H. ----COOH, etc.) which makes the dye stick to the fabric by formation of some salt.The dyed fabric appeared to be coloured because a particular absorbs a radiation of specific wavelength from the visual range of electromagnetic radiation which fall on surface. The remaining radiation (complementary colours) of light is reflected. The colour we observe is due to the reflected light. For example if a dye absorbs the light in the wavelength region corresponding to red, then it would appear green , which is the complementary colour of red. Similarly, if a dye absorbs blue colour, it would appear orange.

Contents

Sl.no Topic

1. Introduction.2. Aim & apparatus.3. Procedure.4. Observation.5. Precaution.6. Scope of the project.7. Bibliography.

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Bibliography1. icbse.com.2. Wikipedia.