A method and a composition for improving color fastness of cellulose based substrates to nitrogen oxides and ozone

Abstract

The presently claimed invention relates to a method for improving color fastness of a cellulose based substrate to nitrogen oxides and ozone. The method comprises contacting the cellulose based substrate with a composition comprising at least one semicarbazide compound selected from bis[4-[3- (dimethylamino)ureido]phenyl]methane (I) and 4,4'-hexamethylenebis(1,1- dimethylsemicarbazide) (II), at least one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, polyethylene glycol and water; R1-OH - A, R2-(OCH2CH2-)nOH - B, R3 -(OCH2(CH3)CH-)mOH - C, wherein R1 is selected from C2-C10 linear or branched alkyl group; R2 is selected from C1-C6 linear or branched alkyl group; n is 1, 2 or 3; R3 is selected from C1-C6 linear or branched alkylene group; and m is 1 or 2; wherein the cellulose based substrate is at least one selected from dyed cellulose based substrate, printed cellulose based substrate, and dyed and printed cellulose based substrate; and (ii) drying.

Description

[0001] M / ARCH-019-PC December 18, 2025

[0002] A method and a composition for improving color fastness of cellulose based substrates to nitrogen oxides and ozone

[0003] Field of the invention

[0004] The present application relates to a method and a composition for improving color fastness of cellulose based substrates to nitrogen oxides and ozone.

[0005] Background of the invention

[0006] Various dyes are susceptible to degradation in the presence of nitrogen oxides and ozone. Cellulose based substrates such as cotton fabrics dyed and / or printed with such dyes are susceptible to gas fading upon exposure to nitrogen oxides and ozone. Dyed and / or printed substrates are often treated with chemical agents to reduce fading due to exposure to nitrogen oxides and ozone.

[0007] US4737155 discloses a treatment with oxadiazine-4-thiones and triazinethiones for improving the ozone fastness.

[0008] However, the chemical agents known for the treatment of cellulose based substrates to prevent fading due to nitrogen oxides and ozone are associated with one or more disadvantages such as a low effectiveness, a negative influence on other fastness properties (e.g. lightfastness) or complex treatment procedures. Some chemical agent based treatments have a low compatibility with other components.

[0009] Therefore, there is a need to provide an effective method and a composition for improving the color fastness of a cellulose based substrate to nitrogen oxides and ozone.

[0010] Thus, it is an object of the present invention to provide a method for improving the color fastness of a cellulose based substrate to nitrogen oxides and ozone. It is also an object of the present invention to provide a composition for improving the color fastness of a cellulose based substrate to nitrogen oxides and ozone. It is desired that the method is simple, and it provides the cellulose based substrate a high colorM / ARCH-019-PC December 18, 2025

[0011] fastness to nitrogen oxides and ozone. Further, it is desired that the method does not negatively influence the other fastness properties of the cellulose based substrate such as lightfastness. Furthermore, it is desired that the method and the composition are compatible with other components.

[0012] Summary of the invention

[0013] Surprisingly, it has been found that the color fastness of a cellulose based substrate to nitrogen oxides and ozone is improved by the method of the present invention comprising contacting the cellulose based substrate with the composition of the present invention. The method of the present invention provides a high improvement in the color fastness of the cellulose based substrate to nitrogen oxides and ozone. The method of the present invention involves treatment of the cellulose based substrate with a composition comprising simple and readily available components. The method is easy to use; and it has a high compatibility.

[0014] Accordingly, an aspect of the presently claimed invention is directed to a method for improving color fastness of a cellulose based substrate to nitrogen oxides and ozone, the method comprising

[0015] (i) contacting the cellulose based substrate with a composition comprising

[0016] at least one semicarbazide compound selected from bis[4-[3-(dimethylamino)ureido]phenyl]methane (I) and 4,4'-hexamethylenebis(1,1 -dimethylsemicarbazide) (II),

[0017]

[0018] di);

[0019] andM / ARCH-019-PC December 18, 2025

[0020] - at least one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, polyethylene glycol and water;

[0021] R1-OH - A,

[0022] R2-(OCH2CH2-)nOH - B,

[0023] R3-(OCH2(CH3)CH-)mOH - C,

[0024] wherein

[0025] R1is selected from C2-C linear or branched alkyl group;

[0026] R2is selected from Ci-Ce linear or branched alkyl group;

[0027] n is 1, 2 or 3;

[0028] R3is selected from Ci-Ce linear or branched alkylene group; and

[0029] m is 1 or 2;

[0030] wherein the cellulose based substrate is at least one selected from dyed cellulose based substrate, printed cellulose based substrate, and dyed and printed cellulose based substrate; and

[0031] (ii) drying.

[0032] Another aspect of the presently claimed invention is directed to a composition for improving color fastness of a cellulose based substrate to nitrogen oxides and ozone, the composition comprising

[0033] at least one semicarbazide compound selected from bis[4-[3-(dimethylamino)ureido]phenyl]methane (I) and 4,4'-hexamethylenebis(1,1 -dimethylsemicarbazide) (II),

[0034] <

[0035]

[0036] (H);M / ARCH-019-PC December 18, 2025

[0037] and

[0038] - at least one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, polyethylene glycol and water;

[0039] R1-OH - A,

[0040] R2-(OCH2CH2-)nOH - B,

[0041] R3-(OCH2(CH3)CH-)mOH - C,

[0042] wherein

[0043] R1is selected from C2-C linear or branched alkyl group;

[0044] R2is selected from Ci-Ce linear or branched alkyl group;

[0045] n is 1, 2 or 3;

[0046] R3is selected from Ci-Ce linear or branched alkylene group; and

[0047] m is 1 or 2.

[0048] Yet another aspect of the presently claimed invention is directed to a method of preparing the composition of the present invention.

[0049] Yet another aspect of the presently claimed invention is directed to use of the composition of the present invention for improving color fastness of a cellulose based substrate to nitrogen oxides and ozone.

[0050] Yet another aspect of the presently claimed invention is directed to a treated cellulose based substrate comprising a cellulose based substrate treated according to the method for improving color fastness to nitrogen oxides and ozone according to the present invention or treated with the composition for improving color fastness to nitrogen oxides and ozone according to the present invention.

[0051] Brief Description of drawingsM / ARCH-019-PC December 18, 2025

[0052] Figure 1 is showing the results of color fastness test according to AATCC-EP1 for 100% cotton fabrics dyed with 0.25% o.w.f. NOVACRON® Blue EC-R, 0.5% o.w.f. NOVACRON® Light Blue SE and 0.5% o.w.f. NOVACRON® Blue C-5X.

[0053] Figures 1T and 1C show pictures of the cotton knit fabric dyed with 0.25% o.w.f. NOVACRON® Blue EC-R treated with the method of the present invention and a comparative untreated fabric (example 15), respectively.

[0054] Figures 2T and 2C show pictures of a cotton knit fabric dyed with 0.5% o.w.f. NOVACRON® Light Blue SE treated with the method of the present invention and a comparative untreated fabric (example 16) respectively.

[0055] Figures 3T and 3C show pictures of a cotton knit fabric dyed with 0.5% o.w.f. NOVACRON® Blue C-5X treated with the method of the present invention and a comparative untreated fabric (example 17), respectively.

[0056] Figure 2 is showing results of color fastness test according to AATCC-164 for fabric dyed with 0.25% o.w.f. NOVACRON® Blue EC-R.

[0057] Figures 4T and 4C show pictures of a cotton knit fabric dyed with 0.25% o.w.f. NOVACRON® Blue EC-R treated with the method of the present invention for 1 cycle and a comparative untreated fabric (example 28), respectively. Figures 5T and 5C show pictures of a cotton knit fabric dyed with 0.25% o.w.f. NOVACRON® Blue EC-R treated with the method of the present invention for 3 cycles and a comparative untreated fabric (example 29), respectively.

[0058] Figure 3 is showing results of color fastness test according to AATCC-109 for fabric dyed with 0.25% o.w.f. NOVACRON® Blue EC-R. Figures 6T and 6C show pictures of a cotton knit fabric dyed with 0.25% o.w.f. NOVACRON® Blue EC-R treated with the method of the present invention for 1 cycle and a comparative untreated fabric (example 32), respectively. Figures 7T and 7C show pictures of a cotton knit fabric dyed with 0.25% o.w.f. NOVACRON® Blue EC-R treated with the method of the present invention for 3 cycles and a comparative untreated fabric (example 33), respectively.

[0059] Detailed description of the inventionM / ARCH-019-PC December 18, 2025

[0060] Before the present compositions and formulations of the presently claimed invention are described, it is to be understood that this invention is not limited to particular compositions and formulations described, since such compositions and formulation may, of course, vary. It is also to be understood that the terminology used herein is not intended to be limiting, since the scope of the presently claimed invention will be limited only by the appended claims.

[0061] If hereinafter a group is defined to comprise at least a certain number of embodiments, this is meant to also encompass a group which preferably consists of these embodiments only. Furthermore, the terms 'first', 'second', 'third' or 'a', 'b', 'c', etc. and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the presently claimed invention described herein are capable of operation in other sequences than described or illustrated herein. In case the terms 'first', 'second', 'third' or '(A)', '(B)' and '(C)' or '(a)', '(b)', '(c)', '(d)', 'i', 'ii' etc. relate to steps of a method or use or assay there is no time or time interval coherence between the steps, that is, the steps may be carried out simultaneously or there may be time intervals of seconds, minutes, hours, days, weeks, months or even years between such steps, unless otherwise indicated in the application as set forth herein above or below.

[0062] Furthermore, the ranges defined throughout the specification include the end values as well i.e. a range of 1 to 10 implies that both 1 and 10 are included in the range. For the avoidance of doubt, applicant shall be entitled to any equivalents according to applicable law.

[0063] In the following passages, different aspects of the presently claimed invention are defined in more detail. Each aspect so defined may be combined with any other aspect or aspects unless clearly indicated to the contrary. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous.M / ARCH-019-PC December 18, 2025

[0064] Reference throughout this specification to 'one embodiment' or 'an embodiment' means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the presently claimed invention. Thus, appearances of the phrases 'in one embodiment' or 'in an embodiment' in various places throughout this specification are not necessarily all referring to the same embodiment but may refer to so.

[0065] Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to a person skilled in the art from this disclosure, in one or more embodiments. Furthermore, while some embodiments described herein include some, but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the presently claimed invention, and form different embodiments, as would be understood by those in the art. Forexample, in the appended claims, any of the claimed embodiments can be used in any combination.

[0066] Dyed and / or printed cellulose based substrates such as fabrics undergo color fading on contact with gaseous substances such as nitrogen oxide and ozone. It is surprisingly found that the color fastness to nitrogen oxides and ozone of the dyed and / or printed cellulose based substrates is improved by the method of the present invention involving treatment of the substrate with a composition comprising at least one semicarbazide compound and at least one solvent. The solvent is capable of dissolving the semicarbazide compound. The composition can be in the form of a solution. The composition can be in the form of a suspension when the semicarbazide compound partially dissolves the solvent.

[0067] Accordingly, an aspect of the presently claimed invention is directed to a method for improving color fastness of a cellulose based substrate to nitrogen oxides and ozone comprising

[0068] (i) contacting the cellulose based substrate with a composition comprisingM / ARCH-019-PC December 18, 2025

[0069] at least one semicarbazide compound selected from bis[4-[3-(dimethylamino)ureido]phenyl]methane (I) and 4,4'-hexamethylenebis(1,1 -dimethylsemicarbazide) (II),

[0070]

[0071] di);

[0072] and

[0073] - at least one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, polyethylene glycol and water;

[0074] R1-OH - A,

[0075] R2-(OCH2CH2)n-OH - B,

[0076] R3-(OCH2(CH3)CH-)mOH - C,

[0077] wherein

[0078] R1is selected from C2-C linear or branched alkyl group;

[0079] R2is selected from Ci-Ce linear or branched alkyl group;

[0080] n is 1, 2 or 3;

[0081] R3is selected from Ci-Ce linear or branched alkylene group; and

[0082] m is 1 or 2;

[0083] wherein the cellulose based substrate is at least one selected from dyed cellulose based substrate, printed cellulose based substrate, and dyed and printed cellulose based substrate; and

[0084] (ii) drying.M / ARCH-019-PC December 18, 2025

[0085] In an embodiment, the step of drying is carried out at a temperature in the range of 110°C to180°C.

[0086] In an embodiment, the method for improving color fastness of a cellulose based substrate to nitrogen oxides and ozone comprises a step of contacting the cellulose based substrate with a composition comprising

[0087] - semicarbazide compound bis[4-[3-(dimethylamino)ureido]phenyl]methane (I),

[0088]

[0089] (I), and

[0090] - at least one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, polyethylene glycol and water;

[0091] R1-OH - A,

[0092] R2-(OCH2CH2)n-OH - B,

[0093] R3-(OCH2(CH3)CH-)mOH - C,

[0094] wherein

[0095] R1is selected from C2-C linear or branched alkyl group;

[0096] R2is selected from Ci-Ce linear or branched alkyl group;

[0097] n is 1, 2 or 3;

[0098] R3is selected from Ci-Ce linear or branched alkylene group; and

[0099] m is 1 or 2;

[0100] wherein the cellulose based substrate is at least one selected from dyed cellulose based substrate, printed cellulose based substrate, and dyed and printed cellulose based substrate.M / ARCH-019-PC December 18, 2025

[0101] In one embodiment, the method for improving color fastness to nitrogen oxides and ozone of a cellulose based substrate comprises a step of contacting the cellulose based substrate with a composition comprising

[0102] - semicarbazide compound 4, 4'-hexamethylenebis(1,1 -dimethylsemicarbazide) (II),

[0103]

[0104] (II); and

[0105] - at least one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, polyethylene glycol and water;

[0106] R1-OH - A,

[0107] R2-(OCH2CH2)n-OH - B,

[0108] R3-(OCH2(CH3)CH-)mOH - C,

[0109] wherein

[0110] R1is selected from C2-C linear or branched alkyl group;

[0111] R2is selected from Ci-Ce linear or branched alkyl group;

[0112] n is 1, 2 or 3;

[0113] R3is selected from Ci-Ce linear or branched alkylene group; and

[0114] m is 1 or 2;

[0115] wherein the cellulose based substrate is at least one selected from dyed cellulose based substrate, printed cellulose based substrate, and dyed and printed cellulose based substrate.

[0116] In an embodiment, the composition further comprises at least one acid selected from organic acid and inorganic acid.

[0117] In an embodiment, the method for improving color fastness to nitrogen oxides and ozone of a cellulose based substrate comprising

[0118] (i) contacting the cellulose based substrate with a composition comprisingM / ARCH-019-PC December 18, 2025

[0119] at least one semicarbazide compound selected from bis[4-[3-(dimethylamino)ureido]phenyl]methane (I) and 4,4'-hexamethylenebis(1,1 -dimethylsemicarbazide) (II),

[0120]

[0121] di);

[0122] - at least one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, polyethylene glycol and water;

[0123] R1-OH - A,

[0124] R2-(OCH2CH2)n-OH - B,

[0125] R3-(OCH2(CH3)CH-)mOH - C,

[0126] wherein

[0127] R1is selected from C2-C linear or branched alkyl group;

[0128] R2is selected from Ci-Ce linear or branched alkyl group;

[0129] n is 1, 2 or 3;

[0130] R3is selected from Ci-Ce linear or branched alkylene group; and

[0131] m is 1 or 2;

[0132] and

[0133] - at least one acid;

[0134] wherein the cellulose based substrate is at least one selected from dyed cellulose based substrate, printed cellulose based substrate, and dyed and printed cellulose based substrate; and

[0135] (ii) drying.M / ARCH-019-PC December 18, 2025

[0136] In an embodiment, R1is selected from C1-C4 linear or branched alkyl group.

[0137] In a preferred embodiment, R1is (CHs -CH-. The alcohol is isopropanol.

[0138] In an embodiment, R2is selected from C1-C4 linear or branched alkyl group.

[0139] In a preferred embodiment, R2is CH3-CH2-CH2-CH2-.

[0140] In a preferred embodiment, R2is CH3-CH2-CH2-CH2- and n is 1. The glycol ether is 2-butoxyethanol.

[0141] In a preferred embodiment, R2is CH3-CH2-CH2-CH2- and n is 2. The glycol ether is diethylene glycol monobutyl ether.

[0142] In a preferred embodiment, R2is CH3-CH2-CH2-CH2- and n is 3. The glycol ether is triethylene glycol monobutyl ether.

[0143] In a preferred embodiment, R2is CH3 and n is 1. The glycol ether is propylene glycol monomethyl ether.

[0144] In an embodiment, R3is selected from C1-C4 linear or branched alkylene group.

[0145] In a preferred embodiment, R3is methyl.

[0146] In an embodiment, R3is CH3- and m is 1. The glycol ether is propyleneglycol monomethyl ether.

[0147] In an embodiment, R3is CH3- and m is 2. The glycol ether is dipropylene glycol monomethyl ether.

[0148] In an embodiment, the polyethylene glycol has a weight average molecular weight in the range of 180 to 800 g / mol.

[0149] As used herein, “molecular weight” or “M. Wt.” refers to the weight average molecular weight unless otherwise stated. Molecular weight is measured using industry standard method, gel permeation chromatography (“GPC”) using THF (1 mL / min) as the mobile phase and using polystyrene as a standard.M / ARCH-019-PC December 18, 2025

[0150] In a preferred embodiment, the polyethylene glycol is selected from PEG 200, PEG 400 and PEG 600.

[0151] In an embodiment, the weight ratio of the at least one semicarbazide to the at least one solvent is in the range of 1:20 to 2:1; and more preferably in the range of 1:20 to 1:2.

[0152] In a preferred embodiment, the weight ratio of the at least one semicarbazide to the at least one solvent is 1 :9.

[0153] In a preferred embodiment, the weight ratio of the at least one semicarbazide to the at least one solvent is 2:7.

[0154] The at least one solvent is preferably one, two or three solvents.

[0155] In one embodiment, the at least one solvent is a mixture of two solvents.

[0156] In a preferred embodiment, the at least one solvent is a mixture of water and one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, and polyethylene glycol.

[0157] In a preferred embodiment, the at least one solvent is a mixture of water and the alcohol of formula A.

[0158] In a more preferred embodiment, the at least one solvent is a mixture of water and isopropanol.

[0159] In a more preferred embodiment, the at least one solvent is a mixture of water and methanol.

[0160] In an embodiment, the weight ratio of the alcohol of formula A and water is in the range of 10:1 to 1:10.

[0161] In an embodiment, the weight ratio of the alcohol of formula A and water is 4:5.

[0162] In an embodiment, the weight ratio of the alcohol of formula A and water is 6:1.M / ARCH-019-PC December 18, 2025

[0163] In an embodiment, the organic acid is at least one selected from malonic acid, succinic acid, glutaric acid, adipic acid, acetic acid, citric acid, methanesulfonic acid, formic acid, malic acid, lactic acid, glycollic acid, polylactic acid, polyacrylic acid, and polymaleic acid.

[0164] In a preferred embodiment, the organic acid is malonic acid.

[0165] In an embodiment, the inorganic acid is at least one selected from hydrochloric acid, sulphuric acid, and phosphoric acid.

[0166] In an embodiment, the weight ratio of the at least one semicarbazide to the at least one acid is in the range of 1:2 to 10:1.

[0167] In a preferred embodiment, the weight ratio of the at least one semicarbazide to the at least one acid is 2:1.

[0168] In an embodiment, the composition further comprises at least one biocide.

[0169] In an embodiment, the composition useful in the present invention is in the form of a solution, and suspension.

[0170] In an embodiment, the composition useful in the present invention is in the form of a solution.

[0171] In an embodiment, the step of contacting is carried out by a process selected from padding and exhaustion process.

[0172] In a preferred embodiment, the step of contacting is carried out by padding.

[0173] In an embodiment, the concentration of the at least one semicarbazide compound in the liquid used for contacting in the padding process is in the range of 10 g / L to 100 g / L.

[0174] In a preferred embodiment, the concentration of the at least one semicarbazide compound in the liquid used for contacting in the padding process is 40 g / L.M / ARCH-019-PC December 18, 2025

[0175] In an embodiment, the cellulose based substrate is selected from a dyed cellulose based substrate, a printed cellulose based substrate, and dyed and printed cellulose based substrate.

[0176] In an embodiment, the cellulose based substrate is selected from cellulose fabric and blend of cellulose with a material selected from polyester, wool, and spandex.

[0177] In an embodiment, the cellulose based substrate is cellulose fabric.

[0178] In an embodiment, the cellulose based substrate is a blend of cellulose with a material selected from polyester, wool, and spandex, wherein the amount of cellulose in the blend is in the range of 35 to 80 wt.%.

[0179] In an embodiment, the cellulose based substrate is selected from a dyed fabric, a printed fabric and a dyed and printed fabric.

[0180] In an embodiment, the cellulose based substrate is dyed with at least one dye.

[0181] In an embodiment, the cellulose based substrate is printed with at least one dye.

[0182] In an embodiment, the cellulose based substrate is dyed with at least one dye and printed with at least one dye.

[0183] In an embodiment, the cellulose based substrate is dyed and / or printed with at least one dyestuff selected from reactive dye, direct dye, sulfur dye and indigo dye.

[0184] In an embodiment, the cellulose based substrate dyed and / or printed with at least one dyestuff selected from blue reactive dye, red reactive dye, black reactive dye and turquoise reactive dye.

[0185] In an embodiment, the cellulose based substrate is dyed with at least one dye selected from Novacron Blue EC-R, Novacron Light Blue SE, Novacron Blue C-5X, NOVACRON Blue C-D, NOVACRON Atlantic EC-NC, NOVACRON Brill. Blue EC-B, NOVACRON Red EC-2BL, NOVACRON Atlantic C-NC and Nylosan Brill Blue F-CLA.M / ARCH-019-PC December 18, 2025

[0186] In an embodiment, the cellulose based substrate is printed with at least one dye selected from NOVACRON Blue P-3R, NOVACRON Black P-SGN and NOVACRON Turquoise P-GR 150%.

[0187] In an embodiment, the cellulose based substrate is dyed with at least one dyestuff selected from Novacron Blue EC-R, Novacron Light Blue SE, Novacron Blue C-5X, NOVACRON Blue C-D, NOVACRON Atlantic EC-NC, NOVACRON Brill. Blue EC-B, NOVACRON Red EC-2BL, NOVACRON Atlantic C-NC and Nylosan Brill Blue F-CLA, and is printed with at least one dyestuff selected from NOVACRON Blue P-3R, NOVACRON Black P-SGN and NOVACRON Turquoise P-GR 150%.

[0188] Another aspect of the presently claimed invention is directed to a composition for improving color fastness of a cellulose based substrate to nitrogen oxides and ozone, the composition comprising

[0189] at least one semicarbazide compound selected from bis[4-[3- (dimethylamino)ureido]phenyl]methane (I) and 4,4'-hexamethylenebis(1,1 - dimethylsemicarbazide) (II),

[0190]

[0191] (II);

[0192] and

[0193] - at least one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, polyethylene glycol and water;

[0194] R1-OH - A,

[0195] R2-(OCH2CH2-)nOH - B,

[0196] R3-(OCH2(CH3)CH-)mOH - C,M / ARCH-019-PC December 18, 2025

[0197] wherein

[0198] R1is selected from C2-C10 linear or branched alkyl group;

[0199] R2is selected from Ci-Ce linear or branched alkyl group;

[0200] n is 1, 2 or 3;

[0201] R3is selected from Ci-Ce linear or branched alkylene group; and

[0202] m is 1 or 2.

[0203] In an embodiment, the composition further comprises at least one acid selected from organic acid and inorganic acid.

[0204] In an embodiment, the composition further comprises at least one biocide.

[0205] Another aspect of the presently claimed invention is directed to a method of preparing the composition according to the present invention comprises the steps of mixing the at least one semicarbazide compound and the at least one solvent to obtain a mixture; and stirring the mixture to obtain the composition.

[0206] In an embodiment, the method of preparing the composition further comprises adding the at least one acid to the mixture.

[0207] In an embodiment, the method of preparing the composition according to the present invention comprises the steps of mixing the at least one semicarbazide compound, the at least one solvent and the at least one acid to obtain a mixture and stirring the mixture to obtain the composition.

[0208] In an embodiment, the method of preparing the composition further comprises adding at least one biocide.

[0209] In an embodiment, the stirring is carried out till the dissolution of solids to obtain a solution.M / ARCH-019-PC December 18, 2025

[0210] In an embodiment, the stirring is carried out for a period between 30 min to 10 hours. The components partially dissolve to provide a suspension.

[0211] Anotheraspect of the presently claimed invention is directed to use of the composition of the present invention for improving the color fastness of a cellulose based substrate to nitrogen oxides and ozone.

[0212] In an embodiment, the cellulose based substrate used is selected from a dyed cellulose based substrate, a printed cellulose based substrate, and dyed and printed cellulose based substrate.

[0213] In an embodiment, the cellulose based substrate used is dyed and / or printed with at least one dyestuff selected from reactive dye, direct dye, sulfur dye and indigo dye.

[0214] Another aspect of the presently claimed invention is directed to a cellulose based substrate treated according to the method for improving color fastness to nitrogen oxides and ozone of the present invention or treated with the composition for improving color fastness to nitrogen oxides and ozone according to the present invention.

[0215] In an embodiment, the treated cellulose based substrate having improved color fastness to nitrogen oxide and ozone as determined by AATCC EP1, ISO 105 G02, AATCC 109, and AATCC164.

[0216] The treated coated cellulose based substrate has a high compatibility with other components such as fixing agents and softners.

[0217] The presently claimed invention offers one or more of the following advantages: - The method of the present invention provides a cellulose based substrate having an improved color fastness to nitrogen oxides and ozone.

[0218] - The method of the present invention is simple.M / ARCH-019-PC December 18, 2025

[0219] - The composition is simple; it is prepared from readily available chemical components by a simple process.

[0220] - The method of the present invention uses a composition that is compatible with various commonly used additives such as fixing agent and softeners.

[0221] - The method or use of the composition of the present invention shows a low influence on the light fastness of the fabric.

[0222] - The method or use of the composition of the present invention shows a low influence on the color change of the fabric.

[0223] - The method or use of the composition of the present invention shows a low influence on the hydrophilicity of the fabric.

[0224] - The method or use of the composition of the present invention shows a low influence on the hand feel of the fabric.

[0225] In the following, there are provided a list of embodiments to further illustrate the present disclosure without intending to limit the disclosure to specific embodiments listed below.

[0226] 1. A method for improving color fastness to nitrogen oxides and ozone of a cellulose based substrate comprising

[0227] (i) contacting the cellulose based substrate with a composition comprising

[0228] at least one semicarbazide compound selected from bis[4-[3- (dimethylamino)ureido]phenyl]methane (I) and 4,4'-hexamethylenebis(1,1 - dimethylsemicarbazide) (II),

[0229]

[0230] di);

[0231] andM / ARCH-019-PC December 18, 2025

[0232] - at least one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, polyethylene glycol and water;

[0233] R1-OH - A,

[0234] R2-(OCH2CH2-)nOH - B,

[0235] R3-(OCH2(CH3)CH-)mOH - C,

[0236] wherein

[0237] R1is selected from C2-C linear or branched alkyl group;

[0238] R2is selected from Ci-Ce linear or branched alkyl group;

[0239] n is 1, 2 or 3;

[0240] R3is selected from Ci-Ce linear or branched alkylene group; and

[0241] m is 1 or 2;

[0242] wherein the cellulose based substrate is at least one selected from dyed cellulose based substrate, printed cellulose based substrate, and dyed and printed cellulose based substrate; and

[0243] (ii) drying.

[0244] 2. The method according to embodiment 1, wherein the composition further comprises at least one acid selected from organic acid and inorganic acid.

[0245] 3. The method according to embodiment 1 or embodiment 2, wherein R1is selected from C1-C4 linear or branched alkyl group.

[0246] . The method according to any of embodiments 1 to 3, wherein R1is (CH3)2-CH-.

[0247] 5. The method according to any of embodiments 1 to 4, wherein R2is selected from C1-C4 linear or branched alkyl group.

[0248] 6. The method according to any of embodiments 1 to 5, wherein R2is CH3-CH2-CH2- CH2-.M / ARCH-019-PC December 18, 2025

[0249] 7. The method according to any of embodiments 1 to 6, wherein n is 1.

[0250] 8. The method according to any of embodiments 1 to 6, wherein n is 2.

[0251] 9. The method according to any of embodiments 1 to 6, wherein n is 3.

[0252] 10. The method according to any of embodiments 1 to 9, wherein R2is -CH3 and n is 1.

[0253] 11. The method according to any of embodiments 1 to 10, wherein R3is selected from C1-C4 linear or branched alkylene group.

[0254] 12. The method according to any of embodiments 1 to 11, wherein R3is -CH3.

[0255] 13. The method according to embodiment 12, wherein R3is -CH3 and m is 1.

[0256] 14. The method according to embodiment 12, wherein R3is CH3 and m is 2.

[0257] 15. The method according to any of embodiments 1 to 14, wherein the polyethylene glycol is selected from PEG 200, PEG 400 and PEG 600.

[0258] 16. The method according to embodiment 2, wherein the organic acid is selected from malonic acid, succinic acid, glutaric acid, adipic acid, acetic acid, citric acid, methanesulfonic acid, formic acid, malic acid, lactic acid, glycollic acid, polylactic acid, polyacrylic acid, and polymaleic acid.

[0259] 17. The method according to embodiment 2, wherein the inorganic acid is selected from hydrochloric acid, sulphuric acid, and phosphoric acid.M / ARCH-019-PC December 18, 2025

[0260] 18. The method according to any of embodiments 1 to 17, wherein the weight ratio of the at least one semicarbazide to the at least one solvent is in the range of 1:20 to 2:1.

[0261] 19. The method according to any of embodiments 1 to 18, wherein the at least one solvent is a mixture of alcohol of formula A and water.

[0262] 20. The method according to embodiment 19, wherein the weight ratio of alcohol of formula A and water is in the range of 1 :5 to 8:1.

[0263] 21. The method according to any of embodiments 1 to 20, wherein the weight ratio of the at least one semicarbazide to the at least one acid is in the range of 1 :2 to 10:1.

[0264] 22. The method according to any of embodiments 1 to 21 further comprising at least one biocide.

[0265] 23. The method according to any of embodiments 1 to 22, wherein the composition is in a form selected from a solution or a suspension.

[0266] 24. The method according to any of embodiments 1 to 23, wherein the composition is in the form of a solution.

[0267] 25. The method according to any of embodiments 1 to 23, wherein the step of contacting is carried out by means of padding, spraying, soaking, brushing or by applying a sponge.

[0268] 26. The method according to any of embodiments 1 to 24, wherein the step of contacting is carried out by padding; and the concentration of the at least one semicarbazide compound in the solution used for padding is in the range of 10 g / L to 100 g / L.M / ARCH-019-PC December 18, 2025

[0269] 27. The method according to embodiment 26, wherein the drying is carried out at a temperature in the range of 110°C to 180°C.

[0270] 28. The method according to any of embodiments 1 to 27, wherein the cellulose based substrate is selected from a dyed cellulose based substrate, a printed cellulose based substrate, and dyed and printed cellulose based substrate.

[0271] 29. The method according to any of embodiments 1 to 28, wherein the cellulose based substrate is selected from cellulose fabric, viscose fabric, and blended fabric of cellulose with at least one material selected from polyester, wool and spandex.

[0272] 30. The method according to any of embodiments 1 to 29, wherein the cellulose based substrate is selected from a dyed cellulose fabric, a printed cellulose fabric and a dyed and printed cellulose fabric.

[0273] 31. The method according to any of embodiments 1 to 30, wherein the cellulose based substrate dyed and / or printed with at least one dyestuff selected from reactive dye, direct dyes, sulfur dyes and indigo dyes.

[0274] 32. The method according to any of embodiments 1 to 30, wherein the cellulose based substrate dyed and / or printed with at least one dyestuff selected from blue reactive dye, red reactive dye, black reactive dye and turquoise reactive dye.

[0275] 33. The method according to any of embodiments 1 to 30, wherein the cellulose based substrate dyed with at least one dyestuff selected from Novacron Blue EC-R, Novacron Light Blue SE, Novacron Blue C-5X, NOVACRON Blue C-D, NOVACRON Atlantic EC-NC, NOVACRON Brill. Blue EC-B, NOVACRON Red EC-2BL, NOVACRON Atlantic C-NC and Nylosan Brill Blue F-CLA.

[0276] 34. The method according to any of embodiments 1 to 31 , wherein the cellulose based substrate is printed with at least one dyestuff selected from NOVACRON Blue P- 3R, NOVACRON Black P-SGN and NOVACRON Turquoise P-GR 150%.M / ARCH-019-PC December 18, 2025

[0277] 35. A composition for improving color fastness to nitrogen oxides and ozone of a cellulose based substrate, the composition comprising

[0278] at least one semicarbazide compound selected from bis[4-[3- (dimethylamino)ureido]phenyl]methane (I) and 4,4'-hexamethylenebis(1,1 - dimethylsemicarbazide) (II),

[0279] <

[0280]

[0281] "

[0282] (ii);

[0283] and

[0284] - at least one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, polyethylene glycol and water;

[0285] R1-OH - A,

[0286] R2-(OCH2CH2-)nOH - B,

[0287] R3-(OCH2(CH3)CH-)mOH - C,

[0288] wherein

[0289] R1is selected from C2-C linear or branched alkyl group;

[0290] R2is selected from Ci-Ce linear or branched alkyl group;

[0291] n is 1, 2 or 3;

[0292] R3is selected from Ci-Ce linear or branched alkylene group; and

[0293] m is 1 or 2.

[0294] 36. The composition according to embodiment 33 further comprising at least one acid selected from organic acid and inorganic acid.M / ARCH-019-PC December 18, 2025

[0295] 37. The composition according to embodiment 33 or 34 further comprising at least one biocide.

[0296] 38. A method of preparing the composition according to any of embodiments 33 to 35 comprising adding at least one semicarbazide compound and at least one solvent to obtain a mixture; and stirring the mixture to obtain the composition.

[0297] 39. The method of preparing the composition according embodiment 36 further comprising adding the at least one acid to the mixture.

[0298] 0. The method according to embodiments 36 or 37 further comprising adding at least one biocide to the mixture.

[0299] 1. The method according to any of embodiments 36 to 38, wherein the stirring is carried out till the dissolution of solids to obtain a solution.

[0300] 2. Use of the composition according to any of the any of embodiments 33 to 35 for improving color fastness of a cellulose based substrate to nitrogen oxides and ozone.

[0301] 3. The use according to embodiment 40, wherein the cellulose based substrate is selected from a dyed cellulose based substrate, a printed cellulose based substrate, and dyed and printed cellulose based substrate.

[0302] 4. The use according to embodiment 40 or 41, wherein the cellulose based substrate is selected from cellulose fabric and blend of cellulose with at least one material selected from polyester, wool and spandex.

[0303] 5. The use according to any of embodiments 40 to 42, wherein the cellulose based substrate is selected from a dyed fabric, a printed fabric and a dyed and printed fabric.M / ARCH-019-PC December 18, 2025

[0304] 6. The use according to any of embodiments 1 to 30, wherein the cellulose based substrate dyed and / or printed with at least one dyestuff selected from reactive dye, direct dye, sulfur dye and indigo dye.

[0305] 7. The use according to any of embodiments 1 to 30, wherein the cellulose based substrate dyed and / or printed with at least one dyestuff selected from blue reactive dye, red reactive dye, black reactive dye and turquoise reactive dye.

[0306] 8. The use according to any of embodiments 40 to 43, wherein the cellulose based substrate dyed with at least one dyestuff selected from Novacron Blue EC-R, Novacron Light Blue SE, Novacron Blue C-5X, NOVACRON Blue C-D, NOVACRON Atlantic EC-NC, NOVACRON Brill. Blue EC-B, NOVACRON Red EC-2BL, NOVACRON Atlantic C-NC and Nylosan Brill Blue F-CLA.

[0307] 9. The use according to any of embodiments 40 to 44, wherein the cellulose based substrate is printed with at least one dyestuff selected from NOVACRON Blue P- 3R, NOVACRON Black P-SGN and NOVACRON Turquoise P-GR 150%.

[0308] 50. A treated cellulose based substrate comprising a cellulose based substrate treated according to the method for improving color fastness to nitrogen oxides and ozone according to any of the embodiments 1 to 32 or treated with the composition for improving color fastness to nitrogen oxides and ozone according to any of claims 33 to 35.

[0309] 51. The treated cellulose based substrate according to embodiment 46, wherein the cellulose based substrate is selected from a cellulose fabric and a blend of cellulose with a material selected from polyester, wool, and spandex.

[0310] 52. The treated cellulose based substrate according to embodiment 46 or claim 47, wherein the cellulose based substrate is a cellulose fabric.

[0311] 53. The treated cellulose based substrate according to any of embodiments 46 to 48, wherein the cellulose based substrate is a cotton fabric.M / ARCH-019-PC December 18, 2025

[0312] 54. The treated cellulose based substrate according to any of embodiments 46 to 49, wherein the cellulose based substrate selected from a dyed fabric, a printed fabric and a dyed and printed fabric.

[0313] 55. The treated cellulose based substrate according to any of embodiments 46 to 50, wherein the cellulose based substrate is a dyed fabric.

[0314] 56. The treated cellulose based substrate according to any of embodiments 46 to 51 having improved color fastness to nitrogen oxide and ozone as determined by AATCC EP1, AATCC164, ISO 105 G02 and AATCC 109.

[0315] While the presently claimed invention has been described in terms of its specific embodiments, certain modifications and equivalents will be apparent to those skilled in the art and are intended to be included within the scope of the presently claimed invention.

[0316] Examples

[0317] The presently claimed invention is illustrated in detail by non-restrictive working examples which follow. More particularly, the test methods specified hereinafter are part of the general disclosure of the application and are not restricted to the specific working examples.

[0318] Materials

[0319] The following materials are used in the Examples:

[0320] NOVACRON® Blue EC-R, NOVACRON® Light Blue SE, NOVACRON® Blue C-5X, NOVACRON® Blue C-D, NOVACRON® Atlantic EC-NC, NOVACRON® Brill. Blue EC-B, NOVACRON® Red EC-2BL, NOVACRON® Atlantic C-NC, Nylosan® Brill Blue F-CLA, NOVACRON® Blue P-3R, NOVACRON® Black P-SGN, and NOVACRON® Turquoise P-GR 150% were available from Archroma China.M / ARCH-019-PC December 18, 2025

[0321] Bis[4-[3-(dimethylamino)ureido]phenyl]methane (I) and 4,4'-hexamethylenebis(1,1 -dimethylsemicarbazide) (II) were obtained from Merck China.

[0322] Methods

[0323] Color fastness of cellulose based substrates to nitrogen oxides was tested according to AATCC standard method EPI -2012.

[0324] Color fastness of cellulose based substrates to nitrogen oxides was tested according to AATCC standard method 164-2019.

[0325] Color fastness of cellulose based substrates to ozone was tested according to AATCC 109-2016.

[0326] Color fastness of cellulose based substrates to burnt-gas fumes was tested according to ISO 105 G02: 1993 / Cor 1 :1995 / Cor 2:2009.

[0327] Examples

[0328] 1) Preparation of a composition of the present invention

[0329] Example 1: Composition of 4, 4'-hexamethylenebis(1,1 -dimethylsemicarbazide) (II) having 10 wt.% concentration

[0330] 10 parts by weight of 4, 4'-hexamethylenebis(1,1 -dimethylsemicarbazide) (II), 40 parts by weight of isopropanol and 50 parts by weight of deionized water were added to a reactor, and the content was stirred thoroughly until a colorless to yellow transparent liquid was obtained.

[0331] Example 2: Composition of bis[4-[3-(dimethylamino)ureido]phenyl]methane (I) having 10 wt.% concentration

[0332] 10 parts by weight of bis[4-[3-(dimethylamino)ureido]phenyl]methane (I), 5 parts by weight of malonic acid, 75 parts by weight of methanol and 10 parts by weight of deionized water were added to a reactor and the content was stirred until a colorless to yellow transparent liquid was obtained.

[0333] 2) Application Examples

[0334] Application of compositions 1 and 2M / ARCH-019-PC December 18, 2025

[0335] The application of compositions 1 and 2 on textile fabrics was carried out by padding in a padder (company Rapid, XIAMEN) having a padding bath containing a solution of semicarbazide having a concentration of 40 g / L. The liquor uptake by the fabric was determined by weighing the finished test samples before and after application. The liquor uptake was found to be 70 wt.%. The treated fabric was subsequent drying in setting machine (XIAMEN Rapid, Model: MINITENTER, No: 9345) at 130°C for 120 seconds.

[0336] The compositions of the present invention were applied to 14 dyed cotton based substrates by the procedure above. The dyed cotton based substrate treated with composition A from example 1 are provided in Table 1.

[0337] Table 1: Substrates treated with composition A comprising 4'-hexamethylenebis(1,1 -dimethylsemicarbazide) (II)

[0338]

[0339] o.w.f. - weight of dye with respect to weight of fabric;

[0340] g / kg - dye weight with respect to printing paste

[0341] The dyed cotton based substrate treated composition B from example 2 are provided in Table 2.M / ARCH-019-PC December 18, 2025

[0342] Table 2: Substrates treated with composition B comprising bis[4-[3-(dimethylamino)ureido]phenyl]methane (I)

[0343]

[0344] Analysis of color fastness

[0345] The finished fabrics obtained as per the application examples were subjected to the following tests:

[0346] 1. Color fastness to nitrogen oxides according to AATCC EP1

[0347] The color fastness to nitrogen oxide was analyzed by the following method. Treated Fabrics from examples 3-12 were exposed to nitrogen oxide by the method provided hereinbelow. Similar fabric specimen that was not treated with the composition of the present invention were used for comparison.

[0348] Test method: Fabric specimen having a dimension of at least 7cmx7cm were employed for this test. The test was carried out at a maintained temperature 20°C and humidity 65% for 24 hours.

[0349] A test tube was charged with 9.0 mL deionized water, followed by 4.0 mL Sodium nitrite 2% aqueous solution. The mixture was stirred evenly, and 1.0 mL phosphoric acid 85% aqueous solution was added to the mixture to obtain test solution. The open end of the test tube was immediately covered the with a fabric specimen, followed by tightly fastening the fabric specimen to the test tube. The exposure of fabric specimen to nitrogen oxide was continued for 120 minutes at room temperature.

[0350] The exposed fabric specimen was separated, and it was rated according to AATCC EP1. The results of AATCC EP1 test as rating of treated cellulose based substrate and untreated cellulose based substrate are summarized in Table 3.

[0351] Table 3: Color fastness to nitrogen oxides according to AATCC EP1 for substrates treated with composition A comprising 4'-hexamethylenebis(1,1 -dimethylsemicarbazide) (II)

[0352]

[0353] M / ARCH-019-PC December 18, 2025

[0354]

[0355] *o.w.f. - weight% of dye with respect to weight of fabric; g / kg - dye weight with respect to printing paste

[0356] Table 4: Color fastness to nitrogen oxides according to AATCC EP1 for substrates treated with composition B comprising bis[4-[3-(dimethylamino)ureido]phenyl]methane (I)

[0357]

[0358] M / ARCH-019-PC December 18, 2025

[0359]

[0360] It is clear from the data provided in Tables 3 and 4 that the treated cellulose based substrates showed a higher color fastness to nitrogen oxides as compared to untreated cellulose based substrate. The photographs of examples 15, 16 and 17 are depicted in Figure 1.

[0361] Thus, the method of the present invention improves color fastness of the cellulose based substrate to nitrogen oxides.

[0362] 2. Colorfastness to oxides of nitrogen in the atmosphere under high humidities according to AATCC 164

[0363] The color fastness of a cotton based substrate to nitrogen oxide was analyzed according to AATCC 164 test method. Treated Fabric of example 12 was exposed to nitrogen oxide under conditions according to AATCC 164 test method. A similar fabric specimen that was not treated with the composition of the present invention was used for comparison.

[0364] The results of AATCC 164 test as rating of treated cellulose based substrate and untreated cellulose based substrate are summarized in Table 5.

[0365] Table 5: Color fastness to nitrogen oxides according to AATCC 164

[0366]

[0367] It is clear from the data provided in Table 5 that the treated cellulose based substrates showed a higher color fastness to nitrogen oxides as compared to untreated cellulose based substrate. The photographs of examples 28 and 29 are depicted in Figure 2.M / ARCH-019-PC December 18, 2025

[0368] Thus, the method of the present invention improves color fastness of the cellulose based substrate to nitrogen oxides.

[0369] 3. Color fastness to burnt-gas fumes according to ISO 105-G02

[0370] The color fastness of cotton based substrate to burnt-gas fumes was analyzed according to ISO 105-G02 test method. Treated Fabric A was exposed to burnt-gas fumes under conditions according to ISO 105-G02 test method. A similar fabric specimen that was not treated with the composition of the present invention was used for comparison.

[0371] The results of ISO 105-G02 test as rating of treated cellulose based substrate and untreated cellulose based substrate are summarized in Table 6.

[0372] Table 6: Color fastness to nitrogen oxides according to ISO 105-G02

[0373]

[0374] It is clear from the data provided in Table 6 that the treated cellulose based substrates showed a higher color fastness to nitrogen oxides and ozone as compared to untreated cellulose based substrate.

[0375] Thus, the method of the present invention improves color fastness of the cellulose based substrate to nitrogen oxides and ozone.

[0376] 4. Color fastness to ozone in the atmosphere under low humidities according to AATCC 109

[0377] The color fastness to ozone was analyzed according to AATCC 109 test method. Treated Fabric A was exposed to ozone under conditions according to AATCC 109 test method. A similar fabric specimen which was not treated with the composition of the present invention was used for comparison.

[0378] The results of AATCC 109 test as rating of treated cellulose based substrate and untreated cellulose based substrate are summarized in Table 7.M / ARCH-019-PC December 18, 2025

[0379] Table 7: Color fastness to ozone

[0380]

[0381] It is clear from the data provided in Table 7 that the treated cellulose based substrates showed a higher color fastness to ozone as compared to untreated cellulose based substrate. After 3 cycles, the difference between treated and untreated specimen is high. The photographs of examples 32 and 33 are depicted in Figure 3.

[0382] Thus, the method of the present invention improves color fastness of the cellulose based substrate to ozone.

Claims

M / ARCH-019-PC December 18, 2025Claims1. A method for improving color fastness of a cellulose based substrate to nitrogen oxides and ozone comprising(i) contacting the cellulose based substrate with a composition comprisingat least one semicarbazide compound selected from bis[4-[3- (dimethylamino)ureido]phenyl]methane (I) and 4,4'-hexamethylenebis(1,1 - dimethylsemicarbazide) (II),< "(II);and- at least one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, polyethylene glycol and water;R1-OH - A,R2-(OCH2CH2-)nOH - B,R3-(OCH2(CH3)CH-)mOH - C,whereinR1is selected from C2-C linear or branched alkyl group;R2is selected from Ci-Ce linear or branched alkyl group;n is 1, 2 or 3;R3is selected from Ci-Ce linear or branched alkylene group; andm is 1 or 2;M / ARCH-019-PC December 18, 2025wherein the cellulose based substrate is at least one selected from dyed cellulose based substrate, printed cellulose based substrate, and dyed and printed cellulose based substrate; and(ii) drying.

2. The method according to claim 1, wherein the composition further comprises at least one acid selected from organic acid and inorganic acid.

3. The method according to claim 2, wherein the organic acid is at least one selected from malonic acid, succinic acid, glutaric acid, adipic acid, acetic acid, citric acid, methanesulfonic acid, formic acid, malic acid, lactic acid, glycollic acid, polylactic acid, polyacrylic acid, and polymaleic acid.

4. The method according to claim 2, wherein the inorganic acid is at least one selected from hydrochloric acid, sulphuric acid, and phosphoric acid.

5. The method according to any of claims 2 to 4, wherein the weight ratio of the at least one semicarbazide to the at least one acid is in the range of 1 :2 to 10:1.

6. The method according to any of claims 1 to 5, wherein the weight ratio of the at least one semicarbazide to the at least one solvent is in the range of 1 :20 to 2:1.

7. The method according to any of claims 1 to 6, wherein the at least one solvent is a mixture of alcohol of formula A and water.

8. The method according to any of claims 1 to 7, wherein the composition is in a form selected from a solution or a suspension.

9. The method according to any of claims 1 to 8, wherein the composition is in the form of a solution.

10. The method according to any of claims 1 to 9, wherein the step of contacting is carried out by means of padding and exhaustion process.

11. The method according to any of claims 1 to 10, wherein the drying is carried out at a temperature in the range of 110°C to 180°C.

12. The method according to any of claims 1 to 11, wherein the cellulose based substrate is selected from cellulose fabric, viscose fabric, and blended fabric of cellulose with at least one material selected from polyester, wool, and spandex.M / ARCH-019-PC December 18, 202513. The method according to any of claims 1 to 12, wherein the cellulose based substrate is dyed and / or printed with at least one dyestuff selected from reactive dye, direct dyes, sulfur dyes and indigo dyes.

14. The method according to any of claims 1 to 13, wherein the cellulose based substrate dyed and / or printed with at least one dyestuff selected from blue reactive dye, red reactive dye, black reactive dye, and turquoise reactive dye.

15. A composition for improving color fastness of a cellulose based substrate to nitrogen oxides and ozone, the composition comprisingat least one semicarbazide compound selected from bis[4-[3- (dimethylamino)ureido]phenyl]methane (I) and 4,4'-hexamethylenebis(1,1 - dimethylsemicarbazide) (II),di);and- at least one solvent selected from alcohol of formula A, glycol ether of formula B, glycol ether of formula C, polyethylene glycol and water;R1-OH - A,R2-(OCH2CH2-)nOH - B,R3-(OCH2(CH3)CH-)mOH - C,whereinR1is selected from C2-C10 linear or branched alkyl group;R2is selected from Ci-Ce linear or branched alkyl group;M / ARCH-019-PC December 18, 2025n is 1, 2 or 3;R3is selected from Ci-Ce linear or branched alkylene group; andm is 1 or 2.

16. The composition according to claim 15 further comprising at least one acid selected from organic acid and inorganic acid.

17. A method of preparing the composition according to claim 15 or 16 comprising adding at least one semicarbazide compound and at least one solvent to obtain a mixture; and stirring the mixture to obtain the composition.

18. Use of the composition according to claim 15 or 16 for improving color fastness of a cellulose based substrate to nitrogen oxides and ozone.

19. The use according to claim 18, wherein the cellulose based substrate is selected from a dyed cellulose based substrate, a printed cellulose based substrate, and dyed and printed cellulose based substrate.

20. The use according to claim 18 or 19, wherein the cellulose based substrate is selected from cellulose fabric and blend of cellulose with at least one material selected from polyester, wool and spandex.

21. A treated cellulose based substrate comprising a cellulose based substrate treated according to the method for improving color fastness to nitrogen oxides and ozone according to any of the claims 1 to 14 ortreated with the composition for improving color fastness to nitrogen oxides and ozone according to claim 15 or 16.

22. The treated cellulose based substrate according to claim 21 having improved color fastness to nitrogen oxide and ozone as determined by AATCC EP1, AATCC164, ISO 105 G02 and AATCC 109.

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