Claims:We claim:
1. A composition for improving color-fastness and wrinkle-resistance of a fabric, the composition comprising:
-a resin in the range of 6.0 % to 12.0 % by weight of the fabric;
-polyurethane in the range of 4.0 % to 8.0 % by weight of the fabric;
-polyethylene in the range of 4.0 % to 8.0% by weight of the fabric;
-a colour deepening agent being at least 5 % by weight of the fabric; and
-adipic acid in the range of 3.0 % to 7.0 % by weight of the fabric, the acid being mixed with an organic solvent.

2. The composition as claimed in claim 1, wherein the resin is a formaldehyde-based resin or non-formaldehyde based resin.

3. The composition as claimed in claim 1, wherein the resin is dimethylol dihydroxy ethylene urea, urea-glyoxal resin or 1, 3-dimethyl -4, 5 dihydroxyimidazolidinone.

4. The composition as claimed in claim 1, wherein the organic solvent is selected from acetone, hexadecyltrimethylammonium OR 2-hydroxy-2,2-dimethylacetophenone (HDMA), p-xylene, benzene, perchloroethylene, tetrachloroethylene , toluene and acetone.

5. The composition as claimed in claim 1, wherein the colour-deepening agent is a non-ionic silicone based agent.

6. A method of improving color-fastness and wrinkle-resistance of a fabric comprising the steps of:
a. mixing adipic acid in the range of 3.0 % to 7.0 % by weight of the fabric with an organic solvent;
b. mixing the solution obtained in step (a) with a resin in the range of 6.0 % to 12.0 % by weight of the fabric, polyurethane in the range of 4.0 % to 8.0 % by weight of the fabric, polyethylene in the range of 4.0 % to 8.0% by weight of the fabric and a colour deepening agent being at least 5 % by weight of the fabric;
c. immersing the fabric in the solution of step (b) for at least 15 minutes; and
d. drying the fabric at a temperature between 70 to 80o C followed by curing the dried fabric at 150 oC for at least 10 minutes.

7. The method as claimed in claim 6, wherein the resin is a formaldehyde-based resin or a non-formaldehyde based resin.

8. The method as claimed in claim 6, wherein the resin is dimethylol dihydroxy ethylene urea, urea-glyoxal resin or 1, 3-dimethyl -4, 5 dihydroxyimidazolidinone.
9. The method as claimed in claim 6, wherein the organic solvent is selected from acetone, hexadecyltrimethylammonium or 2-hydroxy-2,2-dimethylacetophenone (HDMA), p-xylene, benzene, perchloroethylene, tetrachloroethylene and toluene.

10. The method as claimed in claim 6, wherein the colour-deepening agent is a silicon based agent.
, Description:FIELD OF THE INVENTION
[001] The present invention relates to a composition for improving color-fastness and wrinkle-resistance of a fabric. The invention also relates to a method of improving color-fastness and wrinkle-resistance of the fabric.

BACKGROUND OF THE INVENTION
[002] Generally, various types of chemical detergents are used during the process of washing fabrics. However, there are numerous drawbacks associated with repeated use of chemical detergents as some chemicals are very harsh on the fabric due to their caustic nature. When a fabric is repeatedly washed with hard water and different types of detergents, the original color of the fabric begins to fade over time resulting in fabrics having a dull and wrinkled appearance. Furthermore, the fabric may also show pilling, linting, fabric shrinkage etc. When the fabric undergoes several washing cycles, then over time, the fabric loses its shape and colour and, consequently, the life of the fabric is adversely affected.
[003] Detergents clearly play a major role in causing the above problems in fabrics. Most of the detergents available in the market contain surfactants, chlorine or bleach that react with the surface of the fabric during washing. Due to repeated use, these detergents damage the fabric and its overall appearance and texture.
[004] Also, repeated ironing of a fabric can also lead to dullness of the fabric. There is a need for fabrics that retains their original color, texture, shape and appearance even after repeated washing and also one that does not wrinkle easily, so as to obviate the need for ironing out creases in the fabric.

SUMMARY OF THE INVENTION
[005] According to an embodiment of the invention there is provided a composition for improving color-fastness and wrinkle-resistance of a fabric. The composition comprises:
-a resin in the range of 6.0 % to 12.0 % by weight of the fabric;
-polyurethane in the range of 4.0 % to 8.0 % by weight of the fabric;
-polyethylene in the range of 4.0 % to 8.0% by weight of the fabric;
-a colour deepening agent being at least 5 % by weight of the fabric; and
-adipic acid in the range of 3.0 % to 7.0 % by weight of the fabric, the acid being mixed with an organic solvent.
[006] According to another embodiment of the invention there is provided a method of improving color-fastness and wrinkle-resistance of a fabric comprising the steps of:
a. mixing adipic acid in the range of 3.0 % to 7.0 % by weight of the fabric with an organic solvent;
b. mixing the solution obtained in step (a) with a resin in the range of 6.0 % to 12.0 % by weight of the fabric, polyurethane in the range of 4.0 % to 8.0 % by weight of the fabric, polyethylene in the range of 4.0 % to 8.0% by weight of the fabric and a colour deepening agent being at least 5 % by weight of the fabric;
c. immersing the fabric in the solution of step (b) for at least 15 minutes; and
d. drying the fabric at a temperature between 70 to 80o C followed by curing the dried fabric at 150 oC for at least 10 minutes.

DETAILED DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION:
[007] The composition of the present invention aims to protect a fabric from the harshness of detergents used in washing garments.
[008] The resin gets cross-linked with cellulose presents in the fabric. The resin also binds to the other components present in the composition and helps to form a protective coating on and inseparable from the fabric surface. Most preferably, the resin in the composition is present in an amount of 8% by weight on the fabric.
[009] Preferably, the resin in the composition is formaldehyde-based or non-formaldehyde based. The formaldehyde-based resin can be dimethylol dihydroxy ethylene urea whereas, the non- formaldehyde based resin can be 1, 3-dimethyl -4, 5 dihydroxyimidazolidinone or urea-glyoxal resin. A formaldehyde-based resin is ordinarily applied to a fabric along with a suitable catalyst eg. MgCl2. The formaldehyde-based resin catalyst MgCl2 aids in degradation of cellulose present in the fabric and helps in hastening the reaction between the resin and the cellulose. The resin catalyst MgCl2, if used, is generally added to the composition in an amount of about 1% by weight of the fabric.
[010] The polyurethane and the polyethylene also contribute to the overall effect of reduction in “linting” and “pilling” during the washing process. The polyurethane in the composition is most preferably present in an amount of 3.5 % by weight of the fabric. The polyethylene in the composition is most preferably present in an amount of 2.5 % by weight of the fabric.
[011] The adipic acid in the composition is preferably in the form of a powder which is then mixed with an organic solvent. The adipic acid in the composition is most preferably present in an amount of 4 % by weight of the fabric. The organic solvent can selected from acetone, hexadecyltrimethylammonium OR 2-hydroxy-2,2-dimethylacetophenone (HDMA), p-xylene, benzene, perchloroethylene, tetrachloroethylene and toluene.
[012] The color deepening agents serve in maintaining and enhancing the boldness of color of the fabric. The color deepening agents can be silicon based agents or can be poly-siloxene, mixed with polycaprolactone-polymeric resin and an emulsifier.
[013] The ingredients of the composition help in synergistically creating a protective coating on the surface of the fabric which in turn protects the fabric from fading, losing shape, colour, texture and appearance for up to approximately 30 wash cycles. The protective coating that the composition provides to the fabric also serves to protect the fabric from undesirable outcomes upon exposure to environmental factors like dust, UV rays, sunlight.
[014] The composition also helps imparts to the fabric the qualities of wrinkle-resistance, pilling reduction, reduction in lint produced during washing and protection from yellowing or graying in the case of white fabrics. The composition also reduces the effect of linting and pilling during the washing process.
[015] The composition also helps to impart wrinkle-resistance to the fabric as it coats the fabric in such a way that prevents the fabric from getting creased or wrinkled easily.
[016] The following experimental examples are illustrative of the invention but are not intended to limit the scope of the invention:
[017] Example 1: Preparation of composition without adipic acid:
Table 1 shows the amounts of the various constituents used to prepare the composition of the invention however excluding adipic acid mixed in an organic solvent from the composition.
Table 1
Constituents Percentage of the constituent based on weight of the fabric
Resin 8%
Polyurethane 4%
Polyethylene
4%
Resin Catalyst MgCl2 1%
Adipic acid mixed in an organic solvent 0%
Non-ionic silicone 5%

[018] Four samples of fabrics were used in this study. Two samples were navy blue in color, in which one sample was dyed with a high exhaustive dye and the other sample was dyed with a low exhaustive dye. A high exhaustive dye is a multi-functional dye wherein reactive groups are present throughout the structure of the dye as compared to fewer reactive groups in low exhaustive dyes. The remaining two samples were of a light colour, namely khaki colour. Again, one of the khaki samples was dyed with a high exhaustive dye and the other khaki sample was dyed with a low exhaustive dye.
[019] The four samples mentioned above were soaked in the composition of Table 1 for 30 minutes at a pH of 5.5-6.5 (pH controlled by using an acetic acid). The fabrics now coated with the composition were dried at a temperature 70 to 80 degree Celsius and the cured at 150 degree Celsius for at least 10 minutes. The four treated samples and four similar samples which were not treated with the composition of the invention were all then tested using the standard American Association of Textile Chemists and Colorists test (AATCC) Test Method 61 and Non-chlorine AATCC Test Method 172.
[020] The color change of the samples were evaluated based on Gray Scale. The Gray Scale has a rating of 1 to 5, where 1 is inferior and 5 is most superior. The color change of the four samples was evaluated and compared with the four more similarly dyed samples which had not been treated with the composition of the invention. The AATCC test conditions are designed to simulate the appearance of the samples (non-treated and treated samples) after 5 domestic washings or 10 commercial launderings. The results of evaluation for color change of the four sample fabrics treated with the composition of the invention as compared with the samples which were not treated are shown in Table 2. 
Table 2
Sample type Gray Scale rating after AATCC Test Method 61 –color fastness at the equivalent of 5 domestic hand washes; Test performed on composition treated samples
Gray Scale rating after Non-chlorine AATCC Test Method 172- color fastness at the equivalent of 5 domestic hand washes; Test performed on composition treated samples Gray Scale rating after Non-chlorine AATCC Test Method 172-color fastness at the equivalent of 5 domestic hand washes; Test performed on untreated samples
High exhaustive Light Khaki 4 3.5 2.5
High exhaustive Navy Blue 3.5 3 2
Low exhaustive Light Khaki 3.5 3 2
Low exhaustive Navy Blue 3.5 3 1.5

[021] Example 2: Preparation of composition without resin and without adipic acid:
The procedure of Example 1 was replicated in Example 2, but in Example 2, resin and resin catalyst were also excluded from the composition in addition to excluding adipic acid mixed with an organic solvent.. Table 3 shows the amounts of the various constituents used to prepare the composition of the invention however excluding adipic acid and the resin and resin catalyst from the composition.

Table 3
Constituents Percentage of the constituent based on weight of the fabric
Resin 0%
Polyurethane 4%
Polyethylene
4%
Resin Catalyst MgCl2 0%
Adipic acid mixed with an organic solvent 0%
Non-ionic silicone 5%

[022] The four treated samples and four similar samples which were not treated with the composition of the invention were all then tested using the standard American Association of Textile Chemists and Colorists test (AATCC) Test Method 61 and Non-chlorine AATCC Test Method 172. The results of evaluation for color change of the four sample fabrics treated with the composition of the invention as compared with the samples which were not treated are shown in Table 4.
 
Table 4
Sample type Gray Scale rating after AATCC Test Method 61 –color fastness at the equivalent of 5 domestic hand washes; Test performed on composition treated samples
Gray Scale rating after Non chlorine AATCC Test Method 172- color fastness at the equivalent of 5 domestic hand washes; Test performed on composition treated samples
Gray Scale rating after Non-chlorine AATCC Test Method 172- color fastness at the equivalent of 5 domestic hand washes; Test performed on untreated samples

High exhaustive Light Khaki 3.5 3.5 2
High exhaustive Navy blue 3 3.5 2
Low exhaustive Light Khaki 3 3.5 2
Low exhaustive Navy blue 3 3.5 1.5

[023] Example 3: Preparation of composition without polyurethane and without adipic acid:
[024] The procedure of Example 1 was replicated in Example 3, but in Example 3, polyurethane was also excluded from the composition, in addition to excluding adipic acid mixed with an organic solvent. Table 5 shows the amounts of the various constituents used to prepare the composition of the invention however excluding polyurethane and adipic acid from the composition.
Table 5
Constituents Percentage of the constituent based on weight of the fabric
Resin 8%
Polyurethane 0%
Polyethylene
4%
Resin Catalyst MgCl2 1%
Adipic acid mixed with an organic solvent 0%
Non-ionic Silicone 5%

[025] The four treated samples and four similar samples which were not treated with the composition of the invention were all then tested using the standard American Association of Textile Chemists and Colorists test (AATCC) Test Method 61 and Non-chlorine AATCC Test Method 172. The results of evaluation for color change of the four sample fabrics treated with the composition of the invention as compared with the samples which were not treated are shown in Table 6
 
Table 6
Sample type Gray Scale rating after AATCC Test Method 61 –color fastness at the equivalent of 5 domestic hand washes; Test performed on composition treated samples
Gray Scale rating after Non chlorine AATCC Test Method 172- color fastness at the equivalent of 5 domestic hand washes; Test performed on composition treated samples
Gray Scale rating after Non-chlorine AATCC Test Method 172- color fastness at the equivalent of 5 domestic hand washes; Test performed on untreated samples

High exhaustive Light Khaki 4 4 2.5
High exhaustive Navy blue 4 4 2
Low exhaustive Light Khaki 4 4 2
Low exhaustive Navy blue 3.5 3.5 2

[026] Example 4: Preparation of composition without polyethylene
The procedure of Example 1 was replicated in Example 4, but in Example 4, polyethylene was excluded from the composition, and instead adipic acid mixed with an organic solvent was included in the composition. Table 7 shows the amounts of the various constituents used to prepare the composition of the invention however excluding polyethylene from the composition.
 
Table 7
Constituents Percentage of the constituent based on weight of the fabric
Resin 8%
Polyurethane 4%
Polyethylene
0%
Resin Catalyst MgCl2 1%
Adipic acid mixed with acetone 5%
Non-ionic silicone 5%

[027] The four treated samples and four similar samples which were not treated with the composition of the invention were all then tested using the standard American Association of Textile Chemists and Colorists test (AATCC) Test Method 61 and Non-chlorine AATCC Test Method 172. The results of evaluation for color change of the four sample fabrics treated with the composition of the invention as compared with the samples which were not treated are shown in Table 8
 
Table 8
Sample type Gray Scale rating after AATCC Test Method 61 –color fastness at the equivalent of 5 domestic hand washes; Test performed on composition treated samples
Gray Scale rating after Non chlorine AATCC Test Method 172- color fastness at the equivalent of 5 domestic hand washes; Test performed on composition treated samples
Gray Scale rating after Non-chlorine AATCC Test Method 172- color fastness at the equivalent of 5 domestic hand washes; Test performed on untreated samples

High exhaustive Light Khaki 4 4 2.5
High exhaustive Navy blue 4 4 1.5
Low exhaustive Light Khaki 3.5 4 2
Low exhaustive Navy blue 3.5 3.5 1

[028] Example 5: Preparation of composition according to an embodiment of the invention
The procedure of Example 1 was replicated in Example 5, but in Example 5, adipic acid mixed with an organic solvent was included in the composition. Table 9 shows the amounts of the various constituents used to prepare the composition according to an embodiment of the invention.
 
Table 9
Constituents Percentage of the constituent based on weight of the fabric
Resin 8%
Polyurethane 4%
Polyethylene
4%
Resin Catalyst MgCl2 1%
Adipic acid mixed with tetrachloroethylene 5%
Non-ionic silicone 5%

[029] The four treated samples and four similar samples which were not treated with the composition of the invention were all then tested using the standard American Association of Textile Chemists and Colorists test (AATCC) Test Method 61 and Non-chlorine AATCC Test Method 172. The results of evaluation for color change of the four sample fabrics treated with the composition of the invention as compared with the samples which were not treated are shown in Table 10.
 
Table 10
Sample type Gray Scale rating after AATCC Test Method 61 –color fastness at the equivalent of 5 domestic hand washes; Test performed on composition treated samples
Gray Scale rating after Non chlorine AATCC Test Method 172- color fastness at the equivalent of 5 domestic hand washes; Test performed on composition treated samples
Gray Scale rating after Non-chlorine AATCC Test Method 172- color fastness at the equivalent of 5 domestic hand washes; Test performed on untreated samples

High exhaustive Light Khaki 4.5 4 2

High exhaustive Navy blue 4.5 4 2.5
Low exhaustive Light Khaki 4 4
2
Low exhaustive Navy blue 4 3.5 1.5

[030] From Table 10 above, it is clear that the highest gray scale rating of 4.5 under AATCC test method 61 is seen when all the components of the composition of the invention are used to make the composition.
[031] Also, from the observations shown in Examples 1 to 4, it is clear that when the composition of Example 5 is applied to the fabric, the Gray Scale results are superior to the results observed in the remaining examples where one or more ingredients of the composition were excluded. Clearly, in Example 5, all the ingredients of the composition work together to provide a synergistic beneficial effect to the fabric in terms of reduction in fading upon multiple washes.
[032] The above examples are non-limiting. The invention is defined by the claims that follow.