FORM 2
THE PATENT ACT, 1970
(39 of 1970)
AND
THE PATENT RULES, 2006
COMPLETE SPECIFICATION
(Section 10, Rule 13)
TITLE OF THE INVENTION
A NOVEL METHOD FOR SCOURING TEXTILE COTTON
APPLICANT
(A) Name : DR. SREENIVASAN, S.
(B) Nationality : INDIAN
(C) Address:


DIRECTOR,
CENTRAL INSTITUTE FOR RESEARCH ON COTTON TECHNOLOGY, ADENWALA ROAD, MATUNGA, MUMBAI-400 019, MAHARASHTRA, INDIA. (A UNIT OF THE INDIAN COUNCIL OF AGRICULTURAL RESEARCH, A SOCIETY REGISTERED IN INDIA UNDER THE SOCIETIES REGISTRATION ACT, 1860 (21 OF I860))

PREAMBLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed.
1) Title of invention
A NOVEL METHOD FOR SCOURING TEXTILE COTTON
2) Field of invention
The invention relates to textile processing including scouring carried out on textile fibers and/or yarns and/or fabrics including that of cotton.
3) Background of invention with regard to the drawback associated with
known art
Cotton is the most commonly used natural textile fiber, globally. Fibers, yarns and fabrics of cotton and other textile materials are not suitable for dyeing or finishing in their raw state since they have low wettability and low water retention. In cellulose-based fibers, these characteristics are attributed to the non-cellulosic impurities in the materials.
The primary wall of cotton fibers comprises of wax (0.4 - 1.0%), pectic substances (3 - 5%), inorganic matter (1 - 3%), in addition to some proteins, colours and the likes as natural impurities. All these affect wettability and absorbency, which are necessary for the uniformity of bleaching, dyeing, printing and chemical finishing treatments.
Prior to weaving, even loom finished fabrics are to be cleaned, bleached, mercerized and dyed at fiber and/or yarn stages. For proper bleaching and rendering them suitable for dyeing and finishing, textile fabrics including cotton, are subjected to 'cleaning up' processes like singeing, acid-steeping, desizing, kier-scouring and the likes. Good scouring is the foundation of successful finishing.


Prior art
Scouring is the process of removal of the natural impurities from the textile materials. The impurities insoluble in water can be removed by i) extraction process by dissolving these in organic solvents, or by ii) emulsification process that forms stable suspensions of the impurities in water, and / or by iii) saponification process that converts the contaminants into water soluble compounds.
Accordingly, scouring is either solvent or aqueous types. Solvent Scouring is the process where certain organic solvents are added to aqueous scouring formulations to readily dissolve fats, oils and waxes and thereby can be used to purify textiles. Organic solvents have a number of advantages that make them particularly useful for wax removal, but fail to remove motes, metal ions, starch and the likes. Hence, Aqueous Scouring is preferred way since water is non-inflammable, non-toxic, plentiful and economic.
A typical formulation for scouring comprises of i) Caustic (3 - 8% depending on type of process used)), ii) Surfactant (0.2 - 0.4%) and iii) Chelating Agent (0.1 - 0.2%). Caustic or alkali helps to swell and dissolve the motes and to saponify oils and waxes, ii) Surfactant lowers the surface tension so as to wet-out the fabric faster and to emulsify oils and waxes, and iii) Chelating Agents form water dispersible complexes with heavy metals.
Scouring can be carried out either by non-continuous or continuous method. The non-continuous scouring process consists essentially of circulating hot alkali liquor through the cloth, which is formed into a rope and piled in a vessel known as kier, under a saturated steam pressure of up to 30 lb/sq inch, which corresponds to a temperature of about 130 degrees Centigrade. In the continuous process, higher productivity is based on the impregnation of the fabric in an alkali solution followed by a steam ageing stage.
Removal of non-cellulosic natural impurities is achieved in textile processing by alkali scouring performed by immersing the materials in boiling caustic solution.The aim is to produce an absorbent material with an average degree of whiteness and extremely low mechanical and chemical damage for textile dyeing and finishing. However, alkali scouring consumes both time and energy, and produces wastewater containing considerable quantities of salts after the used alkali has been neutralized. While the scouring treatment is beneficial for wettability, when carried out under severe conditions, it induces fibre deterioration, e.g., the creation of crevices in fibres or dissolution of the cuticle and
-3-

primary wall.
In addition, unsatisfactory removal of these impurities in the step of scouring leads to emission of smoke in the step of drying and uneven bleaching, dyeing, and finishing.
The other changes that take place in cotton goods during the scouring process are loss in weight (~ 5-10%), loss in length due to shrinkage during the boiling treatment, alteration in count affected by both losses, and changes in textile strength (generally an increase).
4) Objectives of invention
The main objective of this invention is to provide A Novel Method for Scouring Textile Cotton with non polluting, eco-friendly, energy saving process.
5) Statement of invention
Method
This invention provides A Novel Method for Scouring Textile Cotton, and accordingly, the preferred embodiment of this invention is as follows -
- The present invention provides a simple method for scouring textile cotton in fiber and/or yarn and/or fabric forms.
- The scouring of textile cotton in fiber and/or yarn and/or fabric forms accordingly is carried out by using a nonionic surfactant as a scouring agent.
- Nonionic surfactant in aqueous solution is used at low concentration (0.05 - 0.2%).
- Treatment to the material is given in an open vessel, with a suitable material to liquor ratio which in the present case was 1:30.
- Two treatments with low concentration of the nonionic surfactant in aqueous solution are given to the textile cotton in fiber and/or yarn and/or fabric forms, at temperatures between 70 and 90 degrees Centigrade.
- These treatments are given for a period of 1 to 3 hours.


- Two treatments with low concentration (0.05 - 0.2%) of nonionic surfactant in aqueous solution, in an open vessel at a material to liquor ratio of 1:30, at temperatures between 70 and 90 degrees Centigrade for a period of 1 to 3 hours are sufficient for effective scouring, as evident by increased wettability and absorbency of the cotton fiber and/or yarn and/or fabric (mentioned under the examples, hereunder).
6) Detailed description of the invention with reference to drawing/examples
Fiber properties for two varieties of cotton, namely, Jayadhar and MCU-5, were studied using HVI 900 for grey and treated samples. Table 1 shows the results.
Table 1: Fibre properties before and after treatment

Variety 2.5%SL UR% MIC Tenacity

grey treated grey treated grey treated grey treated
Jayadhar 23.7 22.4 52.0 48.0 5.1 5.1 17.2 18.4
MCU-5 31.7 30.6 46.0 44.0 3.7 3.6 23.5 23.2
As can be seen from the Table 1, the 2.5% span length, micronaire and strength are not affected by the treatment. There is some deterioration in the UR% after treatment indicating more short fibres when the fibre sample is treated for scouring. But, this is an accepted fact, since the sample has to be opened from clumpy state after scouring treatment, which can result in breakage of fibres.
Absorbency based on sinking time was estimated for the treated samples according to IS: 2369-1967. Table 2 gives results of sinking tests for treated fibre samples.
Table 2: Average sinking time for treated fibres

Variety Av. Sinking time (s)
Jayadhar 3.3
MCU-5 4.7
It can be seen that the sinking time is well within the standard required time often


seconds. It may be noted that untreated raw fibre does not sink in ordinary water without wetting agent for hours. However, the treated cotton fibre plug sinks in ordinary water without wetting agent in less than ten seconds as indicated above.
Absorbency (sinking time) of treated fabric samples:
Plain weave fabrics woven from six varieties of cotton were used in the study. Grey as well as treated fabric sample of weight one gram each was gently put on the water surface in flat condition. It was observed that none of the grey fabrics could sink in plain water without wetting agent even after 24 hours. However, fabrics after the present scouring treatment could sink in less than five seconds as can be seen from results given in Table 3.
Table 3: Sinking time of treated fabrics

Variety Sinking time (s)
Jayadhar 1.5
MECH-23 2.2
GCot.Hy.10
3.7
G Coi-23 1.2
H-6 2.3
LRA 3.2
Dyeing behaviour of fabrics treated with new method:
To give aesthetic value to any fabric, it is required to dye it. For this, grey cotton fabric has to be made absorbent. Scouring and kiering are the normal processes used in the present day textile industry to make the fabric absorbent. To make it colour free white, many times it may be bleached. This fabric then can absorb reactive dyes or printing colours. To check the dye-ability of cotton fabrics treated with the new method, the following experiments were carried out.
Dye uptake: This test was carried out using Jaypak 4804 Colour Matching System, and the comparison was made between samples conventionally kiered and treated with new method suggested here at a maximum frequency of 540 Hz.


Table 4: Dye uptake of kiered and treated samples
Variety Colour strength(k/s)
MECH-23 New Treatment 8.0206

Kiered 7.7699
G Cot-23 New Treatment 6.6780

Kiered 5.7576
Table 4 clearly shows that dye uptake of samples treated with new method are better than those of conventionally kiered. Table 5 gives colour strength values for four fabric samples prepared by using cottons of different varieties and treated with the newly developed method. It can be seen from these values that the fabrics have absorbed dye to a good extent.
Table 5: Effect on treated samples

Variety Colour strength(k/s)
LRA 5.4986
GCot.Hy.10
5.8904
H-6 5.3846
MCU-5 6.7484
Colour fastness to washing:
This test was carried out according to IS: 3361-1979, using Viewing Booth and Grey Scales. Table 6 gives the results for fabrics made from cotton varieties MECH-23 and G.Cot-23 and scoured using new method as well as conventional method of keiring. It can be seen that fabric samples scoured with the present treatment not only absorb dye easily but are able to retain it during washing and have wash fastness which is equal to or even better than that for samples conventionally scoured and kier boiled.


Table 6: Comparison of colour fastness to washing

Sample change in colour Staining on

Cotton Wool
MECH-23 New Treatment 4-5 4-5 4-5

Kiered 4 4 4-5
G Cot 23 New Treatment 4-5 4-5 5

Kiered 4-5 4-5 5
Colour fastness to rubbing:
This test was carried out according to IS: 766-1988, using Viewing Booth and Grey Scales. Table 7(a) gives colour fastness to rubbing for fabric samples prepared from cottons of different varieties. Fastness values of 4-5 for each of these samples indicates vary good fastness to rubbing. Similarly, Table 7(b) gives comparative values of rubbing fastness of fabrics prepared from cotton varieties MECH-23 and G.Cot-23 for newly treated and kiered samples. These values do not show any difference between them indicating that fastness to rubbing from new treatment is as good as that from conventionally kiered samples.
Table 7(a):Colour fastness of various treated fabrics

Variety Change in colour
LRA 4-5
GCot.Hy.10
4-5
H-6 4-5
MCU-5 4-5


Table 7(b): Comparison of colour fastness of treated fabrics

Variety Change in colour
MECH-23 New Treatment 4-5

Kiered 4-5
G Cot 23 New Treatment 4-5

Kiered 4-5
Colour fastness to perspiration (acidic and alkaline):
This test was carried out according to IS: 971-1983, using Viewing Booth and Gray Scales. Tables 8(a) & (b) and Tables 9(a) & (b) give values for colour fastness to acidic and alkaline perspirations, respectively. As mentioned above in the other fastness tests, colour fastness to acidic as well as alkaline perspirations is quite good and comparable with that obtained for conventionally kiered samples.
Table 8 (a): Colour fastness to acidic perspiration of treated samples

Variety Change in colour Staining on

Cotton Wool
LRA 4-5 4 5
GCot.Hy.10
4 4 4-5
H-6 4-5 4-5 4-5
MCU-5 4-5 4-5 4-5
Table 8 (b): Comparison of colour fastness to acidic perspiration

Variety Change Staining on

in colour Cotton Wool
MECH-23 New Treatment 4-5 4-5 4-5

Kiered 4-5 3-4 4-5
G Cot 23 New Treatment 4-5 4-5 4-5

Kiered 4-5 4 4-5


Table 9 (a): Colour fastness to alkaline perspiration of treated samples

Variety Change in colour Staining on

Cotton Wool
LRA 4-5 4-5 5
GCot.Hy.10
4-5 4 4-5
H-6 4-5 4-5 4-5
MCU-5 4-5 4 5
Table 9(b): Comparison of colour fastness to alkaline perspiration

Variety Change in colour Staining on

Cotton Wool
MECH-23 New Treatment 4-5 4-5 5

Kiered 4 4 5
G Cot 23 New Treatment 4-5 4-5 5

Kiered 4 4 5
The above results in Tables 4 to 9 clearly indicate that it is possible to dye cotton fabrics treated with the new and simply eco friendly, economic, process with dye uptake as good as or better than the conventional kiered fabric. Also, these samples have good fastness properties.
7) A brief description of the accompanying drawing
No drawing is required to Explain the invention.


8) A summary of invention
The present invention provides "A Novel Method for Scouring Textile Cotton" in fiber and/or yarn and/or fabric forms by using nonionic surfactant as a scouring agent. Two treatments with low concentration (0.05 - 0.2%) of the scouring agent in aqueous solution at temperatures between 70 and 90 degrees Centigrade for a period of 1 to 3 hours are sufficient for effective scouring, as evident by increased wettability and absorbency of the textile cotton fiber and/or yarn and/or fabric.
While a particular embodiment of the said invention has been described, it is expressly understood that the said description is just to understand the invention and not to limit the scope ot this invention. The various modifications and improvements are possible without departing from the ambit and scope of this invention.
9) Claim(s)
What is claimed is:
1. A process for scouring of textile cotton fibres, yarn and fabric, and using 0.05% to 0.2% (non-ionic) wetting agent in an open vessel at a suitable material to liquor ratio which in the present case was of 1:30, soaking the material in liquor and keeping the liquor'at temperature between 70 and 90 degrees Centigrade for a period of 1 to 3 hours, followed by removing the material and washing it with cold water followed by repeating the same process once again with the wetting agent and washing with water and drying the material followed by individualisation of fibres in the case of fibre samples.
2. A process as claimed in claim 1, wherein fibre and/or yarn and/or fabric cotton was used for preparing absorbent cotton textile.
3. A process as claimed in claims 1 and 2 wherein the fabric was dyed with reactive dye.