A wet friction fastness improving agent and preparation method thereof

Abstract

The present invention relates to the technical field of printing and dyeing auxiliaries, and in particular to a method for preparing a wet friction fastness improver, which comprises the following steps: adding dehydrated and preheated polyethylene glycol and toluene diisocyanate to a reactor, stirring through a stirring device, heating during stirring, and then reacting to obtain a polyurethane prepolymer; heating the reactor, adding a crosslinking agent and a thickener to continue the reaction, further adding a composite emulsifier, an antioxidant and a chain extender to react with the polyurethane prepolymer, extending the organic molecular chain, adding deionized water after the reaction, stirring quickly and adjusting the pH value to obtain a wet friction fastness improver emulsion. The present invention significantly improves the stability of the wet friction fastness improver emulsion by introducing a crosslinking agent, a thickener, an antioxidant and a composite emulsifier, avoids the stratification or precipitation problems that are easy to occur in traditional emulsions under these conditions, and improves the reliability and use effect of the emulsion.

Description

Technical Field

[0001] The invention relates to the technical field of printing and dyeing auxiliaries, and more specifically, to a wet rubbing fastness improving agent and a preparation method thereof. Background Art

[0002] Wet friction fastness improvers are mainly used in the textile industry, including natural fiber fabrics such as cotton, linen, silk, as well as polyester, spandex and their blended fabrics. In the production process of various textiles such as upper materials, clothing, home textiles, etc., wet friction fastness improvers play an important role and can effectively improve the quality and durability of products.

[0003] In order to improve the friction fastness performance of the wet friction fastness improver, the patent document with the announcement number CN113389071 B discloses a preparation process of the wet friction fastness improver using polyethylene glycol 400, polyethylene glycol 1500, polyethylene glycol 4000, tripropylene glycol monomethyl ether, glacial acetic acid, toluene diisocyanate, triethanolamine and water. The patent document with the announcement number CN114875677B discloses a preparation process of the wet friction fastness improver using polyethylene glycol, epoxy resin emulsion, toluene diisocyanate, chain extender, surfactant and deionized water.

[0004] Although the preparation processes of the above two wet friction fastness enhancers can effectively improve the wet friction performance, they still have some disadvantages in terms of stability. First, the emulsion may be stratified or precipitated under extreme conditions such as high temperature and high humidity, affecting its reliability in long-term use. Second, although the stability of the emulsion is improved by pH adjustment and chain extension reaction, the reversible reaction of the polymer chain under extreme conditions may cause changes in the physical properties of the emulsion and reduce its durability.

[0005] Therefore, the existing process still has room for optimization in improving emulsion stability, resistance to environmental changes and long-term performance. Summary of the invention

[0006] In view of the shortcomings of the prior art, the object of the present invention is to provide a method for preparing a wet rubbing fastness improver, which is used to improve the stability of the existing wet rubbing fastness improver emulsion.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A method for preparing a wet rubbing fastness improving agent comprises the following steps:

[0009] (1) preheating polyethylene glycol to 100° C., then dehydrating it under vacuum for 2 hours, and cooling it to 20° C.; adding 20-30 parts of the dehydrated and preheated polyethylene glycol and 7-15 parts of toluene diisocyanate into a reaction kettle, stirring it through a stirring device, heating it to 60-70° C. during stirring, reacting it for 1-2 hours, and cooling it to room temperature to obtain a polyurethane prepolymer;

[0010] (2) raising the temperature of the reactor to 70-80° C., adding 0.5-2 parts of a crosslinking agent and 0.5-1.5 parts of a thickener, and reacting for 0.5-1 hour;

[0011] (3) adding 3.5-10 parts of composite emulsifier to the reaction kettle and reacting for 5-10 minutes; then adding 0.1-0.5 parts of antioxidant and stirring evenly;

[0012] (4) adding 0.2-1.4 parts of a chain extender to a reactor, reacting for 1-2 hours, adding 42-53 parts of deionized water, stirring evenly to form an emulsion, adjusting the pH of the emulsion to between 6.5 and 7.5, and cooling to room temperature to obtain a wet friction fastness enhancer.

[0013] Preferably, in step (2), the cross-linking agent is isocyanate or disulfide; and the thickening agent is xanthan gum or hydroxypropyl methylcellulose.

[0014] Preferably, in step (3), the composite emulsifier is a mixture of polyvinyl alcohol, sodium lauryl sulfate, cetyltrimethylammonium chloride, sodium polyphosphate and fluorinated polymer.

[0015] Preferably, the weight ratio of polyvinyl alcohol, sodium lauryl sulfate, cetyltrimethylammonium chloride, sodium polyphosphate and fluorinated polymer in the composite emulsifier is (5-10):(3-5):(2-3):(1-2):(0.5-1).

[0016] Preferably, in step (3), the antioxidant is di-tert-butyl-p-cresol or vitamin E.

[0017] Preferably, in step (4), the chain extender is diethylenetriamine polyether, triethylenetetramine polyether or tetramine polyether.

[0018] Preferably, in step (4), phosphate or citric acid is used to adjust the pH of the emulsion to between 6.5 and 7.5.

[0019] Another object of the present invention is to provide a wet rubbing fastness improving agent prepared by the above-mentioned preparation method.

[0020] Compared with the prior art, the present invention has the following beneficial effects: the present invention significantly improves the stability of the wet friction fastness enhancer emulsion by introducing a crosslinking agent, a thickener, an antioxidant and a composite emulsifier. The emulsion can maintain excellent performance under extreme environments such as high temperature and high humidity, avoiding the stratification or precipitation problems that are easy to occur in traditional emulsions under these conditions, and improving the reliability and use effect of the emulsion. DETAILED DESCRIPTION

[0021] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0022] The endpoints and any values ​​of the ranges disclosed in the present invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be regarded as specifically disclosed in the present invention.

[0023] Example 1

[0024] A method for preparing a wet rubbing fastness improving agent comprises the following steps:

[0025] (1) preheating polyethylene glycol to 110° C., then dehydrating the mixture under vacuum for 1.5 hours, and cooling the mixture to room temperature; adding 20 parts of the dehydrated and preheated polyethylene glycol and 7 parts of toluene diisocyanate into a reaction kettle, stirring the mixture through a stirring device, heating the mixture to 60° C. during stirring, reacting the mixture for 2 hours, and cooling the mixture to room temperature to obtain a polyurethane prepolymer;

[0026] (2) raising the temperature of the reactor to 70°C, adding 0.5 parts of a crosslinking agent and 0.5 parts of a thickener, and reacting for 1 hour;

[0027] (3) adding 3.5 parts of composite emulsifier to the reactor and reacting for 5 minutes; then adding 0.1 parts of antioxidant and stirring evenly;

[0028] (4) adding 0.2 parts of a chain extender to a reactor, reacting for 1 hour, adding 42 parts of deionized water, stirring evenly to form an emulsion, adjusting the pH of the emulsion to between 6.5 and 7.5 with phosphate, and cooling to room temperature to obtain a wet friction fastness enhancer.

[0029] The cross-linking agent in this embodiment is isocyanate, the thickener is xanthan gum, the antioxidant is di-tert-butyl-p-cresol, the chain extender is diethylenetriamine polyether, and the composite emulsifier is composed of polyvinyl alcohol, sodium dodecyl sulfate, hexadecyltrimethylammonium chloride, sodium polyphosphate, and fluorinated polymer (PTFE) mixed in a weight ratio of 6:4:2:2:1.

[0030] Example 2

[0031] A method for preparing a wet rubbing fastness improving agent comprises the following steps:

[0032] (1) preheating polyethylene glycol to 110° C., then dehydrating the mixture under vacuum for 1.5 hours, and cooling the mixture to room temperature; adding 22 parts of the dehydrated and preheated polyethylene glycol and 9 parts of toluene diisocyanate into a reaction kettle, stirring the mixture through a stirring device, heating the mixture to 65° C. during stirring, reacting the mixture for 1.5 hours, and cooling the mixture to room temperature to obtain a polyurethane prepolymer;

[0033] (2) raising the temperature of the reactor to 75° C., adding 0.8 parts of a crosslinking agent and 0.8 parts of a thickener, and reacting for 45 minutes;

[0034] (3) adding 4.8 parts of composite emulsifier to the reactor and reacting for 8 minutes; then adding 0.2 parts of antioxidant and stirring evenly;

[0035] (4) adding 0.5 parts of a chain extender to a reactor, reacting for 1.5 hours, adding 45 parts of deionized water, stirring evenly to form an emulsion, adjusting the pH of the emulsion to between 6.5 and 7.5 with phosphate, and cooling to room temperature to obtain a wet friction fastness enhancer.

[0036] The cross-linking agent in this embodiment is isocyanate, the thickener is xanthan gum, the antioxidant is di-tert-butyl-p-cresol, the chain extender is diethylenetriamine polyether, and the composite emulsifier is composed of polyvinyl alcohol, sodium dodecyl sulfate, hexadecyltrimethylammonium chloride, sodium polyphosphate, and fluorinated polymer (PTFE) mixed in a weight ratio of 6:4:2:2:1.

[0037] Example 3

[0038] A method for preparing a wet rubbing fastness improving agent comprises the following steps:

[0039] (1) preheating polyethylene glycol to 110° C., then dehydrating under vacuum for 1.5 hours, and cooling to room temperature; adding 26 parts of polyethylene glycol and 11 parts of toluene diisocyanate after dehydration and preheating into a reaction kettle, stirring with a stirring device, heating to 70° C. during stirring, reacting for 1.5 hours, and cooling to room temperature to obtain a polyurethane prepolymer;

[0040] (2) raising the temperature of the reactor to 75° C., adding 1.2 parts of a crosslinking agent and 1.1 parts of a thickener, and reacting for 0.5 hours;

[0041] (3) adding 6.5 parts of composite emulsifier to the reaction kettle and reacting for 10 minutes; then adding 0.3 parts of antioxidant and stirring evenly;

[0042] (4) adding 0.8 parts of a chain extender to a reactor, reacting for 2 hours, adding 50 parts of deionized water, stirring evenly to form an emulsion, adjusting the pH of the emulsion to between 6.5 and 7.5 using phosphate, and cooling to room temperature to obtain a wet friction fastness enhancer.

[0043] The cross-linking agent in this embodiment is isocyanate, the thickener is xanthan gum, the antioxidant is di-tert-butyl-p-cresol, the chain extender is diethylenetriamine polyether, and the composite emulsifier is composed of polyvinyl alcohol, sodium dodecyl sulfate, hexadecyltrimethylammonium chloride, sodium polyphosphate, and fluorinated polymer (PTFE) mixed in a weight ratio of 6:4:2:2:1.

[0044] Example 4

[0045] A method for preparing a wet rubbing fastness improving agent comprises the following steps:

[0046] (1) preheating polyethylene glycol to 110° C., then dehydrating the mixture under vacuum for 1.5 hours, and cooling the mixture to room temperature; adding 28 parts of the dehydrated and preheated polyethylene glycol and 13 parts of toluene diisocyanate into a reaction kettle, stirring the mixture through a stirring device, heating the mixture to 65° C. during stirring, reacting the mixture for 1.5 hours, and cooling the mixture to room temperature to obtain a polyurethane prepolymer;

[0047] (2) raising the temperature of the reactor to 80° C., adding 1.6 parts of a crosslinking agent and 1.3 parts of a thickener, and reacting for 0.5 hours;

[0048] (3) adding 8.5 parts of composite emulsifier to the reactor and reacting for 10 minutes; then adding 0.4 parts of antioxidant and stirring evenly;

[0049] (4) adding 1.1 parts of a chain extender to a reactor, reacting for 2 hours, adding 50 parts of deionized water, stirring evenly to form an emulsion, adjusting the pH of the emulsion to between 6.5 and 7.5 with citric acid, and cooling to room temperature to obtain a wet friction fastness enhancer.

[0050] The cross-linking agent in this embodiment is disulfide, the thickener is hydroxypropyl methylcellulose, the antioxidant is vitamin E, the chain extender is triethylenetetramine poly, and the composite emulsifier is composed of polyvinyl alcohol, sodium lauryl sulfate, hexadecyltrimethylammonium chloride, sodium polyphosphate, and fluorinated polymer (PTFE) mixed in a weight ratio of 6:4:2:2:1.

[0051] Example 5

[0052] A method for preparing a wet rubbing fastness improving agent comprises the following steps:

[0053] (1) preheating polyethylene glycol to 110° C., then dehydrating it under vacuum for 1.5 hours, and cooling it to room temperature; adding 30 parts of the dehydrated and preheated polyethylene glycol and 15 parts of toluene diisocyanate into a reaction kettle, stirring it through a stirring device, heating it to 65° C. during stirring, reacting it for 1.5 hours, and cooling it to room temperature to obtain a polyurethane prepolymer;

[0054] (2) raising the temperature of the reactor to 80° C., adding 2 parts of a crosslinking agent and 1.5 parts of a thickener, and reacting for 0.5 hours;

[0055] (3) adding 10 parts of composite emulsifier to the reactor and reacting for 10 minutes; then adding 0.5 parts of antioxidant and stirring evenly;

[0056] (4) 1.4 parts of a chain extender was added to a reactor, and after reacting for 2 hours, 53 parts of deionized water was added, and the mixture was stirred evenly to form an emulsion. The pH of the emulsion was adjusted to between 6.5 and 7.5 using citric acid, and the mixture was cooled to room temperature to obtain a wet friction fastness enhancer.

[0057] The cross-linking agent in this embodiment is disulfide, the thickener is hydroxypropyl methylcellulose, the antioxidant is vitamin E, the chain extender is tetraamino polyether, and the composite emulsifier is composed of polyvinyl alcohol, sodium lauryl sulfate, cetyltrimethylammonium chloride, sodium polyphosphate, and fluorinated polymer (PTFE) mixed in a weight ratio of 6:4:2:2:1.

[0058] Comparative Example 1

[0059] A method for preparing a wet rubbing fastness enhancer, compared with Example 3, the only difference is that no cross-linking agent is added in step (2).

[0060] Comparative Example 2

[0061] A method for preparing a wet rubbing fastness improving agent, compared with Example 3, the only difference is that no thickener is added in step (2).

[0062] Comparative Example 3

[0063] A method for preparing a wet rubbing fastness enhancer, compared with Example 3, the only difference is that no crosslinking agent and thickener are added in step (2), that is, step (2) is omitted.

[0064] Comparative Example 4

[0065] A method for preparing a wet rubbing fastness enhancer, compared with Example 3, the only difference is that no antioxidant is added in step (3).

[0066] Comparative Example 5

[0067] A method for preparing a wet friction fastness enhancer, compared with Example 3, the only difference is that the composite emulsifier in step (3) is composed of hexadecyltrimethylammonium chloride, sodium polyphosphate, and fluorinated polymer (PTFE) mixed in a weight ratio of 2:2:1.

[0068] Comparative Example 6

[0069] A method for preparing a wet friction fastness enhancer, compared with Example 3, the only difference is that the composite emulsifier in step (3) is composed of polyvinyl alcohol, sodium lauryl sulfate, and fluorinated polymer (PTFE) mixed in a weight ratio of 6:4:1.

[0070] Comparative Example 7

[0071] A method for preparing a wet friction fastness enhancer, compared with Example 3, the only difference is that the composite emulsifier in step (3) is composed of polyvinyl alcohol, sodium lauryl sulfate, cetyltrimethylammonium chloride, and sodium polyphosphate mixed in a weight ratio of 6:4:2:2.

[0072] Comparative Example 8

[0073] A method for preparing a wet friction fastness enhancer, compared with Example 3, the only difference is that: the composite emulsifier in step (3) is composed of polyvinyl alcohol, sodium lauryl sulfate, cetyltrimethylammonium chloride, sodium polyphosphate, and fluorinated polymer (PTFE) mixed in a weight ratio of 4:6:2:2:1.

[0074] Comparative Example 9

[0075] A method for preparing a wet friction fastness enhancer, compared with Example 3, the only difference is that the composite emulsifier in step (3) is composed of polyvinyl alcohol, sodium lauryl sulfate, hexadecyltrimethylammonium chloride, sodium polyphosphate, and fluorinated polymer (PTFE) mixed in a weight ratio of 6:4:3.5:0.5:1.

[0076] The compositions of the wet rubbing fastness enhancers in Examples 1-5 and Comparative Examples 1-9 were sorted out to obtain the data in Table 1 below:

[0077] Table 1 Components of wet rubbing fastness enhancers in Examples 1-5 and Comparative Examples 1-9

[0078]

[0079] Comparative Example 10

[0080] A wet friction fastness improving agent was prepared according to the preparation method of Example 3 in the patent document with publication number CN114875677B.

[0081] Test 1

[0082] Cloud point test: The wet friction fastness enhancers prepared in Examples 1-5 and Comparative Examples 1-10 were prepared into 10 g / L dispersions, and respectively prepared into mixed dispersions with sodium chloride, i.e., 10 g / L + 50 g / L sodium chloride, and then 100 g was taken and placed in an induction cooker for heating, and the temperature when the dispersion became turbid was recorded, and this temperature was the cloud point. The results are shown in Table 2.

[0083] Test 2

[0084] Emulsification and dispersion ability test: weigh 50 grams of wet friction fastness enhancer, and then weigh 50 grams of 5# mineral oil, mix them in a beaker, and then place them in a water bath at M℃ (M is set to 80, 90, and 100 in sequence), let them stand until the mixed liquid in the beaker is heated to M℃, stir it with a stirrer for 5 minutes under the heat preservation state, and then quickly pour it into a 100mL measuring cylinder and start timing. When the water layer separates to the 20mL mark on the measuring cylinder, stop timing. This time is the emulsification and dispersion time. Each group is tested 5 times in parallel, and the average emulsification and dispersion time is taken. The longer the emulsification and dispersion time, the better the emulsification and dispersion ability, and vice versa. The results are shown in Table 2.

[0085] Table 2 Comparison of cloud point and emulsification dispersion ability

[0086]

[0087]

[0088] As can be seen from Table 2, the turbidity point of the wet friction fastness improver prepared in Comparative Examples 5 and Comparative Examples 7-10 is less than 100°C, especially when mixed with sodium chloride to form a dispersion, the turbidity point will be further reduced to less than 80°C; the turbidity point of the wet friction fastness improver prepared in Comparative Examples 1-4 and Comparative Examples 6 is slightly improved, but when mixed with sodium chloride to form a dispersion, the turbidity point is still less than 100°C, which is not as good as Examples 1-5. When dyeing with reactive dyes, especially when dyeing dark colors, it is often necessary to add more salt accelerators such as sodium chloride, and the dyeing temperature is 60-90°C. Therefore, if the turbidity of the mixed dispersion of the wet friction fastness improver and sodium chloride is less than 60-90°C, its scope of use will inevitably be reduced. In addition, when mixed with sodium chloride to form a dispersion, the turbidity temperature of Example 3 is higher than that of Comparative Examples 1-4 and Comparative Example 7, indicating that the combination of polyvinyl alcohol and sodium dodecyl sulfate can significantly improve the stability of the emulsion at high temperatures and better ensure the use effect at high temperatures. Further comparison of the emulsification and dispersion capabilities of the embodiments and comparative examples at different temperatures confirms that the use of the composite emulsifier with a specific composition of the present invention to prepare the wet friction fastness enhancer emulsion can enhance the stability of the emulsion in a high temperature environment and improve the performance and application range of the emulsion.

[0089] Test 3

[0090] Caustic alkali resistance test: prepare the wet friction fastness enhancer into a 5g / L dispersion and weigh 50g, then mix it with 50g of 10g / L caustic soda solution. After mixing, the wet friction fastness enhancer concentration is 2.5g / L and the caustic soda concentration is 5g / L. Then let it stand for 10 minutes and observe the stability. If there is no floating matter, no flocculent precipitation, and no precipitation, otherwise it is unstable, which means that the caustic alkali resistance is 5g / L; with the caustic soda concentration of 5g / L as the gradient, increase its concentration in sequence until instability occurs, and the last stable caustic soda concentration is the caustic alkali resistance. The results are shown in Table 3.

[0091] Test 4

[0092] Wet rubbing fastness test: At room temperature, first put the cotton fabric into the dyeing vat, then add 5% (owf) of the wet rubbing fastness enhancer prepared in Examples 1-5 and Comparative Examples 1-10, then add the reactive dye (CI Reactive Red 195), salt and alkali, then heat to 90°C, dye for 90 minutes, and then drain to obtain the dyed fabric. According to "GB / T3920-2008 Textiles Color Fastness Tests for Rubbing Fastness", the higher the grade, the better the wet rubbing fastness performance, and Grade 5 is the best. The results are shown in Table 3.

[0093] Table 3 Comparison of caustic soda resistance and wet friction fastness

[0094] Group Caustic soda resistance Wet rubbing fastness grade Example 1 150g / L 4 Example 2 155g / L 4 Example 3 165g / L 5 Example 4 165g / L 4-5 Example 5 160g / L 4 Comparative Example 1 130g / L 4 Comparative Example 2 140g / L 4-5 Comparative Example 3 110g / L 3-4 Comparative Example 4 145g / L 4-5 Comparative Example 5 115g / L 4 Comparative Example 6 120g / L 4 Comparative Example 7 135g / L 4-5 Comparative Example 8 140g / L 4 Comparative Example 9 135g / L 4 Comparative Example 10 125g / L 5 Blank Group / 2

[0095] Note: In the blank group, the reactive dye-dyed cotton fabrics were treated without using wet rubbing fastness enhancer.

[0096] It can be seen from Table 3 that the wet rubbing fastness improving agent prepared by the present invention has excellent caustic soda resistance and can significantly improve the wet rubbing fastness of dyed cotton fabrics.

[0097] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for preparing a wet rubbing fastness improving agent, characterized in that: The following steps are involved: (1) adding 20-30 parts of polyethylene glycol and 7-15 parts of toluene diisocyanate after dehydration and preheating into a reaction kettle, stirring with a stirring device, heating to 60-70° C. during stirring, reacting for 1-2 hours, and cooling to room temperature to obtain a polyurethane prepolymer; (2) raising the temperature of the reactor to 70-80° C., adding 0.5-2 parts of a crosslinking agent and 0.5-1.5 parts of a thickener, and reacting for 0.5-1 hour; (3) adding 3.5-10 parts of composite emulsifier to the reaction kettle and reacting for 5-10 minutes; then adding 0.1-0.5 parts of antioxidant and stirring evenly; (4) adding 0.2-1.4 parts of a chain extender to a reactor, reacting for 1-2 hours, adding 42-53 parts of deionized water, stirring evenly to form an emulsion, adjusting the pH of the emulsion to between 6.5 and 7.5, and cooling to room temperature to obtain a wet friction fastness enhancer.

2. The method for preparing the wet rubbing fastness improving agent according to claim 1, characterized in that: In step (2), the cross-linking agent is isocyanate or disulfide; and the thickening agent is xanthan gum or hydroxypropyl methylcellulose.

3. The method for preparing the wet rubbing fastness improving agent according to claim 1, characterized in that: In step (3), the composite emulsifier is a mixture of polyvinyl alcohol, sodium lauryl sulfate, hexadecyltrimethylammonium chloride, sodium polyphosphate, and fluorinated polymer.

4. The method for preparing the wet rubbing fastness improving agent according to claim 3, characterized in that: The weight ratio of polyvinyl alcohol, sodium dodecyl sulfate, hexadecyltrimethylammonium chloride, sodium polyphosphate and fluorinated polymer in the composite emulsifier is (5-10):(3-5):(2-3):(1-2):(0.5-1).

5. The method for preparing the wet rubbing fastness improving agent according to claim 1, characterized in that: In step (3), the antioxidant is di-tert-butyl-p-cresol or vitamin E.

6. The method for preparing the wet rubbing fastness improving agent according to claim 5, characterized in that: In step (4), the chain extender is diethylenetriamine polyether, triethylenetetramine polyether or tetramine polyether.

7. The method for preparing the wet rubbing fastness improving agent according to claim 5, characterized in that: In step (4), phosphate or citric acid is used to adjust the pH of the emulsion to between 6.5 and 7.

5.

8. A wet rubbing fastness improving agent, characterized in that: The invention is prepared by the preparation method of the wet rubbing fastness improving agent according to any one of claims 1 to 7.

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