A method for characterizing the degree of crosslinking of a resin permanent press finish on a cellulosic fabric

Abstract

The application belongs to the technical field of textiles, and particularly relates to a method for characterizing the crosslinking degree of resin non-iron finishing of cellulose fiber fabric. After cotton and viscose fabric are subjected to resin non-iron finishing, methylene blue dye is used to dye the two kinds of fabric before and after finishing at normal temperature. Compared with the traditional infrared spectrum analysis method and reducing sugar method, the application adopts a simple and fast dyeing method, and can intuitively and rapidly judge the crosslinking degree of the cellulose fiber fabric after resin non-iron finishing and the finishing liquid.

Description

Technical Field

[0001] This invention relates to the field of textile technology, specifically to a method for characterizing the degree of crosslinking of resin in cellulose fiber fabrics after wrinkle-free finishing, belonging to the field of eco-friendly dyeing and finishing technology for textiles. Background Technology

[0002] Cellulose fiber fabrics possess numerous excellent properties, including high breathability, good moisture absorption, easy dyeing, comfortable wear, and natural environmental friendliness. These properties meet modern society's demands for healthy, comfortable, and environmentally friendly clothing, making them highly popular among consumers. However, these fabrics also have drawbacks such as being prone to wrinkling and having poor shape retention, often requiring wrinkle-free finishing to overcome these issues.

[0003] In actual production, it was found that, despite both being cellulose fabrics, cotton and viscose fabrics, after undergoing the same wrinkle-free finishing process, exhibited different formaldehyde contents. This difference is attributed to the varying degrees of cross-linking between the fabric and the finishing agent. Sufficient cross-linking between the finishing agent and the fabric is an effective way to reduce formaldehyde release, and the worse the hydrolytic stability of the cross-linking bonds, the greater the formaldehyde release.

[0004] Common methods for detecting the degree of cross-linking in wrinkle-free finishing processes include enzyme-catalyzed degradation, sulfation, dyeing, chromatography, acid-base titration, infrared spectroscopy, and high-performance liquid chromatography (HPLC). Researchers often use dyeing, glucose concentration colorimetry, and HPLC to evaluate the degree of cross-linking between the finishing agent and the fabric.

[0005] However, the key reagent used in the staining method is 2,4,6-trinitrophenol (picric acid), which is difficult to store and poses a high risk; the glucose concentration colorimetric method requires cellulase, the enzyme activity of which is difficult to control and the operation is inconvenient; although the high performance liquid chromatography method is accurate, it has too high requirements for equipment, which is difficult for general units to achieve.

[0006] There is an urgent need for a method that can quickly and easily determine the degree of crosslinking between cellulose fiber fabrics and resin finishing agents. This method should also be easy to operate, highly feasible, and use readily available and simple raw materials. Summary of the Invention

[0007] [Technical Issues]

[0008] The technical problem to be solved by this invention is to provide a method for characterizing the degree of crosslinking of cellulose fiber fabrics with resin-based wrinkle-free finishing. This method allows for a simple and rapid qualitative determination of the degree of crosslinking between cellulose fiber fabrics and resin finishing agents. The method is convenient to operate, highly feasible, and uses readily available and simple raw materials.

[0009] [Technical Solution]

[0010] After resin-based wrinkle-free finishing, the finishing agent cross-links with the cellulose fiber fabric via ether bonds. Sufficient cross-linking between the finishing agent and the fabric is an effective way to reduce formaldehyde release. The worse the hydrolytic stability of the cross-linking bonds, the greater the formaldehyde release. Methylene blue (MB) is a cationic dye, and cellulose fiber fabrics contain a large number of hydroxyl groups that carry a negative charge in water. The positive and negative charges attract each other, and the methylene blue dye combines with the hydroxyl groups of the fabric. Therefore, the hydroxyl content of the wrinkle-free finished fabric can be judged by the depth of color after dyeing, indirectly characterizing the degree of cross-linking between the fabric and the finishing agent.

[0011] The first objective of this invention is to provide a method for characterizing the degree of crosslinking of resin-treated cellulose fiber fabrics, comprising the following steps:

[0012] (1) Prepare the dyeing solution for cationic dyes;

[0013] (2) Use the cationic dye solution obtained in step (1) to dye the cotton and viscose fabrics before and after the wrinkle-free finishing, and let them air dry naturally.

[0014] (3) Determine the degree of cross-linking between the fabric and the finishing agent based on the color depth of the fabric.

[0015] In one embodiment of the present invention, the cationic dye is one of methylene blue, cationic red, cationic blue, and cationic turquoise blue.

[0016] In one embodiment of the present invention, the cationic dye is preferably methylene blue.

[0017] In one embodiment of the present invention, step (2) specifically involves mixing cationic dye with cotton and viscose fabrics before and after wrinkle-free finishing, adding deionized water and penetrant JFC, and then swirling and dyeing.

[0018] In one embodiment of the present invention, the amount of cationic dye used in step (1) is 0.2-1% owf.

[0019] In one embodiment of the present invention, the bath ratio for staining in step (2) is 1:100-1:200.

[0020] In one embodiment of the present invention, the amount of JFC used in step (2) is 1-5 g / L;

[0021] In one embodiment of the present invention, the dyeing conditions for the cationic dye in step (2) are as follows: dyeing at 25-45℃ for 1 hour, drying, and then observing the color change under a D65 light source.

[0022] In one embodiment of the present invention, the cellulose textiles include any one of cellulose fibers or composite fibers containing cellulose fibers, yarns, blankets, woven fabrics, knitted fabrics, thermal insulation wadding, fillings, nonwoven fabrics, clothing, clothing accessories, home textiles, decorations, medical and health products, or special work clothes.

[0023] In one embodiment of the present invention, the cellulose fiber includes natural cellulose fiber and man-made cellulose fiber. The beneficial effects of the present invention are:

[0024] (1) Cellulose fiber fabrics treated with resin will cross-link with the finishing agent, and the degree of cross-linking is closely related to the wrinkle-free performance of the fabric. This method can intuitively and quickly reflect the change in the degree of cross-linking of cellulose fiber fabrics before and after resin treatment, which is simpler and more convenient than the current methods for evaluating the degree of cross-linking.

[0025] (2) Methylene blue is used to color cotton and viscose fabrics before and after finishing, which clearly reflects the degree of cross-linking of the fabric. This method is easy to operate, highly feasible, and the raw materials used are readily available and easy to store, and the equipment used is inexpensive. Attached Figure Description

[0026] Figure 1 The following are examples of cotton fabrics dyed with 0.5% owf methylene blue dye: (a) cotton fabric before finishing, (b) cotton fabric after finishing, (c) viscose fabric before finishing, and (d) viscose fabric after finishing.

[0027] Figure 2 The following are examples of cotton fabrics dyed with 1.0% owf methylene blue dye: (a) cotton fabric before finishing, (b) cotton fabric after finishing, (c) viscose fabric before finishing, and (d) viscose fabric after finishing.

[0028] Figure 3 The following are examples of cotton fabrics dyed with 0.5% owf cationic red dye before finishing, cotton fabrics after finishing, viscose fabrics before finishing, and viscose fabrics after finishing: (a) cotton fabric before finishing, (b) cotton fabric after finishing, (c) viscose fabric before finishing, and (d) viscose fabric after finishing.

[0029] Figure 4 The following are examples of cotton fabrics dyed with 1.0% owf cationic red dye before finishing, cotton fabrics after finishing, viscose fabrics before finishing, and viscose fabrics after finishing: (a) cotton fabric before finishing, (b) cotton fabric after finishing, (c) viscose fabric before finishing, and (d) viscose fabric after finishing.

[0030] Figure 5The following are examples of cotton fabrics dyed with 0.5% owf cationic blue dye before finishing, cotton fabrics after finishing, viscose fabrics before finishing, and viscose fabrics after finishing: (a) cotton fabric before finishing, (b) cotton fabric after finishing, (c) viscose fabric before finishing, and (d) viscose fabric after finishing.

[0031] Figure 6 The following are examples of cotton fabrics dyed with 1.0% owf cationic blue dye before finishing, cotton fabrics after finishing, viscose fabrics before finishing, and viscose fabrics after finishing: (a) cotton fabric before finishing, (b) cotton fabric after finishing, (c) viscose fabric before finishing, and (d) viscose fabric after finishing.

[0032] Figure 7 The following are examples of cotton fabrics dyed with 0.5% owf cationic turquoise blue dye before finishing, cotton fabrics after finishing, viscose fabrics before finishing, and viscose fabrics after finishing: (a) cotton fabric before finishing, (b) cotton fabric after finishing, (c) viscose fabric before finishing, and (d) viscose fabric after finishing.

[0033] Figure 8 The following are examples of cotton fabrics dyed with 1.0% owf cationic turquoise blue dye before finishing, cotton fabrics after finishing, viscose fabrics before finishing, and viscose fabrics after finishing: (a) cotton fabric before finishing, (b) cotton fabric after finishing, (c) viscose fabric before finishing, and (d) viscose fabric after finishing. Detailed Implementation

[0034] To further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, and not for limiting the scope of the claims of the present invention.

[0035] K / S value: The staining depth K / S of the sample was measured under D65 light source and 10° field of view conditions.

[0036] The fabric used in this application is prepared according to the following method:

[0037] (1) Prepare an ultra-low formaldehyde wrinkle-free finishing liquid, the formula of which is as follows:

[0038]

[0039]

[0040] (2) The viscose fabric is treated without wrinkle, dipped and rolled twice, with the roll residue rate kept at 80%, dried in a high-temperature oven and baked in a heat setter.

[0041] Example 1:

[0042] Cut 0.2g of cotton and viscose fabric before and after finishing, weigh 0.001g of methylene blue dye, maintain the dye dosage at 0.5% owf, add 30g of deionized water to ensure a liquor ratio of 1:150, add 3g / L of penetrant JFC, and dye at 30℃ with vortex shaking at 120r / min for 1h. After drying, observe the color change under a D65 light source. Figure 1 As shown.

[0043] The residual solution after staining with 0.5% OWF methylene blue was diluted 10 times, and the absorbance of the residual solution was measured at a wavelength of 664 nm using a 10 mm cuvette on a UV spectrophotometer, as shown in Table 1.

[0044] The K / S value of the cotton fabric before resin wrinkle-free finishing obtained by dyeing according to this method is 7.0173, and the K / S value after finishing is 6.3536; the K / S value of the viscose fabric before resin wrinkle-free finishing is 8.7173, and the K / S value after finishing is 6.2935, as shown in Table 1.

[0045] Table 1. K / S values ​​and residual absorbance values ​​of cellulose fiber fabrics dyed with 0.5% owf methylene blue.

[0046]

[0047] Example 2:

[0048] Cut 0.2g of cotton and viscose fabric before and after finishing. Weigh 0.002g of methylene blue dye, maintaining a dye dosage of 1.0% owf. Add 24g of deionized water to ensure a liquor ratio of 1:120. Add 5g / L of penetrant JFC. Dye at 35℃ with vortex shaking at 120r / min for 1 hour. After drying, observe the color change under a D65 light source. Figure 2 As shown.

[0049] The residual solution after staining with 1.0% OWF methylene blue was diluted 10 times, and the absorbance of the residual solution was measured at a wavelength of 664 nm using a 10 mm cuvette on a UV spectrophotometer, as shown in Table 2.

[0050] The K / S value of the cotton fabric before resin wrinkle-free finishing obtained by dyeing according to this method is 11.8970, and the K / S value after finishing is 9.6264; the K / S value of the viscose fabric before resin wrinkle-free finishing is 22.1650, and the K / S value after finishing is 17.6510, as shown in Table 2.

[0051] Table 2. K / S values ​​and residual absorbance values ​​of cellulose fiber fabrics dyed with 1.0% owf methylene blue.

[0052]

[0053]

[0054] Example 3

[0055] Referring to Example 1, methylene blue was replaced with cationic red, maintaining the dye dosage at 0.5% owf. 30g of deionized water was added to ensure a bath ratio of 1:150. 3g / L of penetrant JFC was added, and staining was performed at 35°C with vortexing at 120 rpm for 1 hour. After drying, the color change was observed under a D65 light source. Figure 3 As shown.

[0056] The residual solution after staining with 0.5% OWF cationic red was diluted 2 times, and the absorbance of the residual solution was measured at a wavelength of 531 nm using a 10 mm cuvette on a UV spectrophotometer, as shown in Table 3.

[0057] The K / S value of the cotton fabric before resin wrinkle-free finishing obtained by dyeing according to this method is 1.4646, and the K / S value after finishing is 1.2152; the K / S value of the viscose fabric before resin wrinkle-free finishing is 1.6613, and the K / S value after finishing is 0.9319, as shown in Table 3.

[0058] Table 3. K / S values ​​and residual absorbance values ​​of cellulose fiber fabrics dyed with 0.5% owf cationic red.

[0059]

[0060] Example 4

[0061] Referring to Example 2, methylene blue was replaced with cationic red, maintaining the dye dosage at 1.0% owf. 24g of deionized water was added to ensure a bath ratio of 1:120. 5g / L of penetrant JFC was added, and staining was performed at 40°C with vortexing at 120 rpm for 1 hour. After drying, the color change was observed under a D65 light source. Figure 4 As shown.

[0062] The residual solution after staining with 1.0% OWF cationic red was diluted 5 times, and the absorbance of the residual solution was measured at a wavelength of 531 nm using a 10 mm cuvette on a UV spectrophotometer, as shown in Table 4.

[0063] The K / S value of the cotton fabric before resin wrinkle-free finishing obtained by dyeing according to this method is 2.2804, and the K / S value after finishing is 2.1840; the K / S value of the viscose fabric before resin wrinkle-free finishing is 2.7804, and the K / S value after finishing is 1.5981, as shown in Table 4.

[0064] Table 4. K / S values ​​and residual absorbance values ​​of cellulose fiber fabrics dyed with 1.0% owf cationic red.

[0065]

[0066] Example 5

[0067] Referring to Example 1, methylene blue was replaced with cationic blue, maintaining the dye dosage at 0.5% owf. 30g of deionized water was added to ensure a bath ratio of 1:150. 3g / L of penetrant JFC was added, and staining was performed at 35°C with vortexing at 120 rpm for 1 hour. After drying, the color change was observed under a D65 light source. Figure 5 As shown.

[0068] Take the residual solution after staining with 0.5% OWF cationic blue and measure the absorbance of the residual solution at a wavelength of 606 nm using a 10 mm cuvette on a UV spectrophotometer, as shown in Table 5.

[0069] The K / S value of the cotton fabric before resin wrinkle-free finishing obtained by dyeing according to this method is 3.7506, and the K / S value after finishing is 3.0597; the K / S value of the viscose fabric before resin wrinkle-free finishing is 4.6520, and the K / S value after finishing is 2.7990, as shown in Table 5.

[0070] Table 5. K / S values ​​and residual absorbance values ​​of cellulose fiber fabrics dyed with 0.5% owf cationic blue.

[0071]

[0072] Example 6

[0073] Referring to Example 2, methylene blue was replaced with cationic blue, maintaining the dye dosage at 1.0% owf. 24g of deionized water was added to ensure a bath ratio of 1:120. 5g / L of penetrant JFC was added, and staining was performed at 40°C with vortexing at 120 rpm for 1 hour. After drying, the color change was observed under a D65 light source. Figure 6 As shown.

[0074] The residual solution after staining with 1.0% OWF cationic blue was diluted 2 times, and the absorbance of the residual solution was measured at a wavelength of 606 nm using a 10 mm cuvette on a UV spectrophotometer, as shown in Table 6.

[0075] The K / S value of the cotton fabric before resin wrinkle-free finishing obtained by dyeing according to this method is 5.6316, and the K / S value after finishing is 5.2122; the K / S value of the viscose fabric before resin wrinkle-free finishing is 6.0326, and the K / S value after finishing is 4.5739, as shown in Table 6.

[0076] Table 6. K / S values ​​and residual absorbance values ​​of cellulose fiber fabrics dyed with 1.0% owf cationic blue.

[0077]

[0078] Example 7

[0079] Referring to Example 1, methylene blue was replaced with cationic turquoise blue, maintaining the dye dosage at 0.5% owf. 30g of deionized water was added to ensure a bath ratio of 1:150. 3g / L of penetrant JFC was added, and staining was performed at 30°C with vortexing at 120 rpm for 1 hour. After drying, the color change was observed under a D65 light source. Figure 7 As shown.

[0080] The residual solution after staining with 0.5% OWF cationic red was diluted 10 times, and the absorbance of the residual solution was measured at a wavelength of 654 nm using a 10 mm cuvette on a UV spectrophotometer, as shown in Table 7.

[0081] The K / S value of the cotton fabric before resin wrinkle-free finishing obtained by dyeing according to this method is 4.9756, and the K / S value after finishing is 4.7096; the K / S value of the viscose fabric before resin wrinkle-free finishing is 5.9554, and the K / S value after finishing is 2.9080, as shown in Table 7.

[0082] Table 7. K / S values ​​and residual absorbance values ​​of 0.5% owf cationic turquoise blue dyed cellulose fiber fabrics

[0083]

[0084] Example 8

[0085] Referring to Example 2, methylene blue was replaced with cationic turquoise blue, maintaining the dye dosage at 1.0% owf. 24g of deionized water was added to ensure a bath ratio of 1:120. 5g / L of penetrant JFC was added, and staining was performed at 35°C with vortexing at 120 rpm for 1 hour. After drying, the color change was observed under a D65 light source. Figure 8 As shown.

[0086] The residual solution after staining with 1.0% OWF cationic red was diluted 10 times, and the absorbance of the residual solution was measured at a wavelength of 654 nm using a 10 mm cuvette on a UV spectrophotometer, as shown in Table 8.

[0087] The K / S value of the cotton fabric before resin wrinkle-free finishing obtained by dyeing according to this method is 6.6178, and the K / S value after finishing is 6.2893; the K / S value of the viscose fabric before resin wrinkle-free finishing is 11.3970, and the K / S value after finishing is 5.0591, as shown in Table 8.

[0088] Table 8. K / S values ​​and residual absorbance values ​​of cellulose fiber fabrics dyed with 1.0% owf cationic turquoise blue.

[0089]

[0090] After being dyed with methylene blue, the untreated cotton fabric is slightly lighter in color than the viscose fabric, such as Figure 1 ,2 As shown, the reason is that viscose fibers have a larger amorphous region, lower crystallinity, and a looser structure, resulting in more exposed hydroxyl groups than cotton fibers, which facilitates the diffusion and adsorption of methylene blue dye. However, after wrinkle-free finishing, both fabrics are lighter in color than the unfinished fabric. Because methylene blue is a cationic dye, cotton and viscose fibers, due to their high hydroxyl content, carry a negative charge in water. After finishing, the hydroxyl groups on the fabric cross-link with the finishing agent through ether bonds, significantly reducing the hydroxyl content. This leads to less binding of dye molecules to the fiber, resulting in a lighter color compared to the unfinished fabric.

[0091] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. A method for characterizing the degree of crosslinking of resin in wrinkle-free finishing of cellulose fiber fabrics, characterized in that, Includes the following steps: (1) Prepare a cationic dye solution; the cationic dye is one of methylene blue, cationic red, cationic blue, and cationic turquoise blue; the amount of dye used in the cationic dye solution is 0.2-1% owf; (2) Use the cationic dye solution obtained in step (1) to dye the cotton and viscose fabrics before and after the wrinkle-free finishing, and air dry them naturally; the dyeing conditions for the cationic dye are: dyeing at 25-45 ℃ for 1 hour; (3) Determine the degree of cross-linking between the fabric and the finishing agent based on the color depth of the fabric; Cotton and viscose fibers carry a negative charge in water due to the large number of hydroxyl groups they contain. After finishing, the hydroxyl groups on the fabric cross-link with the finishing agent in the form of ether bonds, which greatly reduces the hydroxyl content. This results in less binding of dye molecules to the fiber, and thus the color of the finished fabric is lighter than that of the unfinished fabric.

2. The method according to claim 1, characterized in that, The cationic dye is methylene blue.

3. The method according to claim 1, characterized in that, Step (2) involves mixing cationic dye with cotton and viscose fabrics before and after wrinkle-free finishing, adding deionized water and penetrant JFC, and then swirling and dyeing.

4. The method according to claim 1, characterized in that, The bath ratio for staining in step (2) is 1:100 - 1:

200.

5. The method according to claim 3, characterized in that, In step (2), the amount of JFC used is 1-5 g / L.

6. The method according to claim 1, characterized in that, The conditions for dyeing the cationic dye in step (2) are as follows: dye at 25-45 ℃ for 1 hour, and observe the color change under a D65 light source after drying.

7. The method according to claim 1, characterized in that, The cellulose fiber fabric includes any one of the following: cellulose fiber or composite fiber containing cellulose fiber, yarn, blanket fabric, woven fabric, knitted fabric, thermal insulation wadding, filling material, nonwoven fabric, clothing, clothing accessories, home textiles, decorations, medical and health products, or special work clothes.

Images