Durable deepening agent for fabric as well as preparation method and application of durable deepening agent

Abstract

The invention provides a durable deepening agent for fabric as well as a preparation method and application thereof, and belongs to the technical field of textile assistants. The porous silicon dioxide composite material is prepared by compounding 60-90 parts by mass of a porous silicon dioxide particle dispersion liquid and 10-40 parts by mass of a water-based adhesive. The durable deepening agent for the fabric, provided by the invention, not only effectively improves the surface color depth of a dark-color fabric, but also effectively improves the binding strength between the deepening agent and fibers, realizes durable deepening of the fabric, and has a wide application prospect in the field of dyed textile finishing.

Description

Technical Field

[0001] The present application relates to a durable darkening agent for fabrics and a preparation method and application thereof, belonging to the technical field of textile auxiliaries. Background Art

[0002] Color, as the most important appearance feature of textiles, is one of the key factors that determine the quality of fabrics. Dark fabrics, especially ultra-dark textiles represented by black, have a huge sales market and extremely high economic value at home and abroad due to their mysterious and noble color style. However, the dyeing process of dark fabrics is often accompanied by more dye consumption, which greatly increases the dyeing cost of the fabric; in addition, due to the limited saturation dyeing rate of the dye, the use of excessive dyes usually leads to increased fabric floating color and reduced color fastness and washing fastness; moreover, the large amount of dyes remaining in the dyeing wastewater further increases the difficulty and cost of subsequent sewage treatment.

[0003] It is an effective means of fabric deepening by constructing a layer of low-refractive index resin film on the fiber surface to reduce the amount of light reflected by the fiber surface, thereby obtaining a better apparent color depth. Among them, the most commonly used fabric deepening agent is a silicone finishing agent. Patents CN101446038B and CN106835717B disclose a fabric deepening and brightening agent based on amino silicone oil and phenyl silicone oil, respectively. However, silicone deepening agents are generally giant emulsions, which are often not stable enough during storage and use, and are prone to demulsification, sticking to rollers, and oil spots on the fabric surface. In addition, when silicone deepening agents are used alone, they often cannot meet the processing requirements of printing and dyeing companies for extra-dark black fabrics.

[0004] In recent years, the anti-reflection and structural deepening technology based on the principle of "moth eye bionics" has attracted widespread attention from scientists and the industrial community at home and abroad. Patent CN104074053B discloses a fabric deepening agent based on cross-linked polymethacrylate. Patent CN 112300348 A discloses a "hard core and soft shell" type structural fabric deepening agent with silica as the core and fluorine-containing polymers and polyacrylates as the shell. Patent CN 109206559 A discloses a three-layer fabric deepening agent with polymethacrylate as the core layer, polyacrylate containing epoxy groups as the middle layer, and polysiloxane as the shell layer. This type of finishing agent uses the high conformal properties of inorganic particles or polymers with high glass transition temperatures to construct a porous rough structure on the fiber surface, effectively reducing the reflection of incident light on the fabric surface, thereby achieving fabric deepening. However, after such fabrics are subjected to external effects such as friction and washing, the rough structure is easily destroyed or falls off, resulting in poor durability of fabric deepening.

[0005] Therefore, it is very important to develop a fabric darkening agent with good darkening effect, good durability and simple application process. Summary of the invention

[0006] In view of this, the present application first provides a durable darkening agent for fabrics, which not only effectively improves the color depth of the dark fabric surface, but also effectively improves the bonding strength between the darkening agent and the fiber, thereby achieving durable darkening of the fabric, so as to solve the problems of unsatisfactory darkening effect and poor durability of existing finishing agents.

[0007] Specifically, the present application is implemented through the following scheme: A durable darkening agent for fabrics is prepared by compounding 60 to 90 parts by weight of porous silicon dioxide particle dispersion and 10 to 40 parts by weight of water-based adhesive.

[0008] Further, as a preference: The water-based adhesive is one or more of silica hydrosol, poly(glycidyl methacrylate)-b-polyethylene glycol monomethyl ether monomethacrylate, poly(glycidyl methacrylate)-b-polyethylene glycol monomethyl ether monomethacrylate-b-poly(hexafluorobutyl methacrylate), and poly(n-butyl acrylate)-b-polyacrylic acid emulsion. The solid content of the emulsion is preferably 30%. The addition of the water-based adhesive is beneficial to improving the bonding force between the porous silica particles and the fibers, and improving the durability of the fabric darkening agent.

[0009] The preparation method of poly(glycidyl methacrylate)-b-poly(ethylene glycol) monomethyl ether monomethacrylate) water-based adhesive is as follows: dissolving glycidyl methacrylate and polyethylene glycol monomethyl ether monomethacrylate in N,N-dimethylformamide and heating to a reaction temperature, then adding an initiator solution to the mixed solution to continue the reaction, and finally obtaining a uniform and stable adhesive emulsion. The adhesive emulsion is dried under a certain condition, then washed with ethanol for multiple times, and then dissolved in water to obtain a water-based adhesive.

[0010] The preparation method of poly(glycidyl methacrylate)-b-poly(ethylene glycol) monomethyl ether monomethacrylate)-b-poly(hexafluorobutyl methacrylate) water-based adhesive is as follows: glycidyl methacrylate, hexafluorobutyl methacrylate, and polyethylene glycol monomethyl ether monomethacrylate are dissolved in N,N-dimethylformamide and heated to a reaction temperature, and then an initiator solution is added to the mixed solution to continue the reaction, and finally a uniform and stable adhesive emulsion is obtained. After the adhesive emulsion is dried, it is washed with ethanol for multiple times, and finally it is dissolved in water to obtain a water-based adhesive.

[0011] The porous silica particles used in the porous silica particle dispersion have a size of 30 to 100 nm, and the porous silica particles used may be in a spherical or chain-like form.

[0012] The porous silica particle dispersion is a mesoporous silica particle dispersion or a hollow silica particle dispersion.

[0013] The mesoporous silica particle dispersion is prepared by the following method: Mix hexadecyltrimethylammonium chloride, sodium acetate trihydrate and deionized water, and stir the mixture vigorously at 65-75°C for 20-40 min; then add tetraethoxysilane, continue stirring and reacting for 6-20 h, and obtain a milky white uniformly dispersed mesoporous silica dispersion; centrifuge and wash the dispersion several times and then redisperse it in water to obtain a mesoporous silica particle dispersion. More preferably, mesitylene is also included, and hexadecyltrimethylammonium chloride, sodium acetate trihydrate and deionized water are mixed. Mesitylene can increase the pore size and porosity of porous silica, thereby effectively improving the deepening effect of the deepening agent.

[0014] The hollow silica particle dispersion is prepared by the following method: an ammonia solution containing polyacrylic acid is mixed with ethanol, and then tetraethoxysilane is injected into the mixture for multiple times (e.g., 5 times) at room temperature and under strong stirring conditions, with an interval of 1 to 3 hours each time, and stirring is continued for 5 to 15 hours to obtain a milky white dispersion, and then the dispersion is centrifuged and washed multiple times to remove the polyacrylic acid, and then redispersed in water to obtain a hollow silica dispersion.

[0015] The above-mentioned durable darkening agent for fabrics is mainly composed of porous silica dispersion and water-based adhesive. The low refractive index of porous silica dispersion such as mesoporous or hollow enables it to effectively improve the color depth of the dark fabric surface, and the introduction of water-based adhesive effectively improves the bonding strength between the darkening agent and the fiber, thereby achieving durable darkening of the fabric.

[0016] The second purpose of the applicant is to provide a method for preparing a durable darkening agent for fabrics, wherein a porous silica particle dispersion and an aqueous adhesive are mixed and added to a reaction container, and stirred at a speed of 500 to 1500 rpm for 10 to 80 minutes at room temperature to obtain a uniformly dispersed durable darkening agent for fabrics.

[0017] The third purpose of the present application is to provide the application of the above-mentioned durable darkening agent for fabrics, which is used for textile finishing. The durable darkening agent for fabrics has broad application prospects in the field of dyed textile finishing.

[0018] Compared with the prior art, the present invention has the following beneficial effects: (1) Unlike other technologies that contain solid silica or polymer particles, the mesoporous or hollow silica particles of the present invention contain a large amount of air (the refractive index of air is about 1), so the fabric treated with the durable darkening agent has a better darkening effect, eliminating the problems of poor stability and limited darkening effect of silicone darkening agents.

[0019] (2) A water-based adhesive is added to the mesoporous or hollow silica dispersion in the present invention, which can tightly fix the silica particles on the fiber surface during high-temperature baking, avoiding the problem that the darkening particles are easily detached from the fiber surface, and effectively improving the durability of the darkening fabric.

[0020] (3) The durable darkening agent for fabrics prepared by the present invention will not affect the strength and air permeability of the original fabrics.

[0021] (4) The durable darkening agent provided by the present invention has a simple process, is easy to implement and control, and is conducive to popularization and application. By using the durable darkening agent, textiles can obtain an ideal durable darkening effect through a simple dipping-rolling-baking process, and have broad application prospects in the field of ultra-dark black textile processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The color comparison of the fabric before and after finishing in Example 1 is shown; Figure 2 The color comparison of the fabric before and after finishing in Example 2; Figure 3 The color comparison of the fabric before and after finishing in Example 3; Figure 4 The following is the color comparison of the fabric before and after finishing in Comparative Example 1. DETAILED DESCRIPTION

[0023] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0024] Example 1

[0025] The durable darkening agent for fabrics in this embodiment is prepared by the following steps: Preparation of mesoporous silica particle dispersion: 25 g of hexadecyltrimethylammonium chloride was dissolved in 75 g of water, and then the solution was added to 15 L of water containing 30 g of sodium acetate trihydrate, and the mixed solution was vigorously stirred at 75 °C for 30 min; then 125 mL of tetraethoxysilane was added, and the stirring reaction was continued for 10 h to obtain a milky white uniformly dispersed dispersion; the obtained dispersion was centrifuged and washed several times and then redispersed in water, and the solid content of the dispersion was adjusted to 20%.

[0026] (2) Preparation of poly(glycidyl methacrylate)-b-poly(ethylene glycol) monomethyl ether monomethacrylate) water-based adhesive: 24 g of glycidyl methacrylate and 32 g of polyethylene glycol monomethyl ether monomethacrylate were dissolved in 200 mL of N,N-dimethylformamide and heated to 65 °C. Then, 24 mL of initiator solution was added to the mixture and reacted for 15 h to obtain a uniform and stable adhesive emulsion. The adhesive emulsion was dried at 50 °C, washed with ethanol several times, and finally dissolved in water to obtain a water-based adhesive.

[0027] (3) The mesoporous silica dispersion prepared in step (1) and the poly(glycidyl methacrylate)-b-polyethylene glycol monomethyl ether monomethacrylate) adhesive prepared in step (2) are mixed in a mass ratio of 6:1, and stirred at a speed of 600 rpm for 45 min at room temperature to obtain a durable darkening agent for fabrics.

[0028] Example 2

[0029] The durable darkening agent for fabrics in this embodiment is prepared by the following steps: Preparation of mesoporous silica particle dispersion: 25 g of hexadecyltrimethylammonium chloride was dissolved in 75 g of water, and then the solution was added to 15 L of water containing 30 g of sodium acetate trihydrate, and then 38 g of mesitylene was added, and vigorously stirred at 75 °C for 30 min; then 125 mL of tetraethoxysilane was added, and the stirring reaction was continued for 10 h to obtain a milky white uniformly dispersed dispersion; the obtained dispersion was centrifuged and washed several times and then redispersed in water, and the solid content of the dispersion was adjusted to 20%.

[0030] Preparation of poly(glycidyl methacrylate)-b-poly(ethylene glycol) monomethyl ether monomethacrylate)-b-poly(hexafluorobutyl methacrylate) water-based adhesive: 30 g of glycidyl methacrylate, 30 g of hexafluorobutyl methacrylate, and 40 g of polyethylene glycol monomethyl ether monomethacrylate were dissolved in 250 mL of N,N-dimethylformamide and heated to 65°C, and then 30 mL of initiator solution was added to the mixture and reacted for another 15 h to finally obtain a uniform and stable adhesive emulsion. The adhesive emulsion was dried at 50°C, then washed with ethanol several times, and finally dissolved in water to obtain a water-based adhesive.

[0031] (3) The mesoporous silica dispersion prepared in step (1) and the poly(glycidyl methacrylate)-b-polyethylene glycol monomethyl ether monomethacrylate)-b-poly(hexafluorobutyl methacrylate) aqueous adhesive (solid content 30%) prepared in step (2) are mixed in a mass ratio of 6:1, and stirred at a speed of 600 rpm at room temperature for 45 min to obtain a durable darkening agent for fabrics.

[0032] Example 3

[0033] The durable darkening agent for fabrics in this embodiment is prepared by the following steps: (1) Preparation of hollow silica particle dispersion: 35 g of polyacrylic acid was dissolved in 1.75 L of ammonia water to obtain a clear and transparent solution, and then 45 L of ethanol was quickly added to the above solution, and the solution turned milky white. Then, 1.05 L of tetraethoxysilane was injected into the above mixture at room temperature and under strong stirring conditions, with an interval of 1 h each time, and stirring was continued for 10 h to obtain a milky white dispersion. The dispersion was then centrifuged and washed several times to remove polypropylene alcohol, and then redispersed in water to obtain a hollow silica dispersion, and the solid content of the dispersion was adjusted to 20%.

[0034] (2) The mesoporous silica dispersion prepared in step (1) and a silica aqueous adhesive (solid content 30%, Levasil CC301, Nouryon Chemical Co., Ltd.) were mixed in a mass ratio of 5:1, and stirred at a speed of 600 rpm for 45 min at room temperature to obtain a durable darkening agent for fabrics.

[0035] Comparative Example 1

[0036] This comparative example is configured the same as Example 3, except that no silica water-based adhesive is added: Preparation of hollow silica particle dispersion: 35 g of polyacrylic acid was dissolved in 1.75 L of ammonia water to obtain a clear and transparent solution, and then 45 L of ethanol was quickly added to the above solution, and the solution turned milky white. Then, 1.05 L of tetraethoxysilane was injected into the above mixture 5 times at room temperature and under strong stirring conditions, with an interval of 1 h each time, and stirring was continued for 10 h to obtain a milky white dispersion. The dispersion was then centrifuged and washed several times to remove polypropylene alcohol, and then redispersed in water to obtain a hollow silica dispersion, and the solid content was adjusted to 20%. The obtained dispersion was used as a darkening agent.

[0037] Comparative Example 2

[0038] The durable darkening agent for fabric in this comparative example is prepared by the following steps: 100 g of a commercially available silica hydrosol (LUDOX® AM colloidal silica, Sigma-Aldrich (Shanghai) Trading Co., Ltd.) with a solid content of 30% and 18 g of the poly(glycidyl methacrylate)-b-polyethylene glycol monomethyl ether monomethacrylate) aqueous adhesive (solid content of 30%) in Example 1 were mixed, and stirred at 600 rpm for 45 min at room temperature to obtain a darkening agent.

[0039] Comparative Example 3

[0040] The comparative example darkening agent is prepared by the following steps: (1) Preparation of pre-emulsion: Add 34 g of octadecyltrimethylammonium chloride, 34 g of fatty alcohol polyoxyethylene ether and 2 kg of deionized water into a beaker, heat and stir, and control the temperature at 60 °C. After the emulsifier is completely dissolved, add 900 g of methyl methacrylate monomer, 450 g of N-hydroxyethyl acrylamide and 50 g of methacryloyloxyethyl trimethylammonium chloride into the beaker, and disperse in a disperser at 7000 r / min for 3 min to obtain a pre-emulsion.

[0041] (2) Add 10% of the pre-emulsion mass to the reactor, and at the same time add 10% of the mass of azobisisobutylamidine dihydrochloride aqueous solution of a certain mass percentage concentration prepared in advance, adjust the reaction temperature to 70 ° C, stir at 300 r / min, react for 15 min, until the emulsion turns blue, add the remaining pre-emulsion and initiator aqueous solution drop by drop to the above reactor, and control the drop time to 2 h. After all the drop additions are completed, react for 3 h, cool to 40 ° C, add 0.5 mL of the pre-prepared 1 mol / L sodium hydroxide aqueous solution, adjust the pH to around 7, and obtain a darkening agent emulsion.

[0042] The darkening agents prepared in Examples 1, 2, 3 and Comparative Examples 1, 2, 3 were used for darkening finishing of fabrics respectively, and the process was as follows: A dispersion or emulsion with a solid content of 20% was prepared into a darkening finishing working solution with a concentration of 30 g / L. A dark black polyester fabric was selected and dried at 130 °C for 2 min using a one-dip and one-roll method.

[0043] Darkening rate (D (K / S)): The K / S value of the darkened fabric is measured by Datacolor colorimeter. The darkening rate DK / S is the percentage increase of the K / S value of the darkened fabric compared to the K / S value of the unfinished fabric.

[0044] Improve the fabric's friction resistance: According to GB / T4802.2-2008, the fabric is tested for friction using a Martindale abrasion tester to determine the change in the K / S value of the fabric before and after friction.

[0045] The darkening effect and abrasion resistance of black polyester fabric treated with fabric darkening agent are shown in Table 1.

[0046] Table 1: Darkening effect and color fastness to rubbing of black polyester fabrics treated with darkening agents obtained by different processes .

[0047] In the above scheme, Comparative Example 2 uses commercially available solid silica nanoparticles, Comparative Example 3 uses solid polymethacrylate particles, and the nanoparticles used in Examples 1, 2, 3 and Comparative Example 1 are mesoporous or hollow silica nanoparticles, respectively.

[0048] As can be seen from Table 1, after the fabric darkening agent provided by the present application is used for darkening finishing of black polyester fabric, the hollow or mesoporous structured nanoparticles give the finished fabric a good darkening effect, and the darkening rate is greater than 45% (see Examples 1, 2, 3 and Comparative Example 1); however, only the fabrics treated in Examples 1, 2, and 3 also have good durability, and after 500 Martindale abrasion tester frictions, the darkening rate is slightly reduced.

[0049] Taking Example 3 as an example, Comparative Example 1 uses the same hollow silica particle dispersion, which gives the treated fabric a darkening effect comparable to that of Example 3. However, after 500 Martindale abrasions, the darkening rate of Comparative Example 1 is significantly reduced.

[0050] It can be seen that the fabric darkening agent provided in the present application, which contains both an aqueous adhesive and a nanoparticle dispersion with a hollow or mesoporous structure, effectively improves the bonding strength between the darkening agent and the fiber in this case, and while significantly improving the fabric darkening effect, it also significantly improves the fabric darkening durability.

[0051] Comparative Example 2 uses commercially available silica hydrosol and polymethacrylate glycidyl-b-polyethylene glycol monomethyl ether monomethacrylate aqueous adhesive to form a deepening agent, and the deepening effect is not as good as the deepening effect provided by Example 1 of this case. Although the decrease is small after 500 Martindale abrasion tester frictions, its initial fabric deepening rate is only 37.83%, which is mainly due to the significant increase in the refractive index of solid silica nanoparticles compared with porous silica nanoparticles. This also further confirms that the fabric deepening agent containing mesoporous or hollow silica nanoparticles in this application can significantly improve the fabric deepening effect.

[0052] Comparative Example 3 also has a certain deepening effect, and its initial fabric deepening rate is 29%. After the fabric is rubbed 500 times, the deepening rate is significantly reduced. It can be seen that the fabric deepening agent provided by the present application has good durability while significantly deepening, and effectively solves the problems of poor stability and limited deepening effect of the organic silicon deepening agent.

[0053] By comparing Example 1 with Example 2, it can be seen that: although both of them form a mesoporous silica dispersion, when isotriene is added during the preparation of the mesoporous silica dispersion, the pore size and porosity of the porous silica can be increased, thereby giving the obtained darkening agent a significantly high darkening effect.

[0054] By comparing Example 1 and Example 3, it can be seen that both the mesoporous silica dispersion and the hollow silica dispersion can give the darkening agent good darkening effect and friction durability, and the hollow silica nanoparticles have a lower refractive index than mesoporous silica, giving the fabric a better darkening effect.

[0055] The fabric color comparison before and after finishing of Example 1, Example 3 and Comparative Example 1 is as follows: Figure 1 , Figure 2 and Figure 3 As shown, it can be seen that the use of the solution of the present application can have a significant darkening effect on black polyester, while the darkening effect of Example 1 is not very obvious.

[0056] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A durable darkening agent for fabrics, characterized in that: The porous silica particle dispersion is prepared by compounding 60 to 90 parts by weight of porous silica particle dispersion and 10 to 40 parts by weight of aqueous adhesive.

2. A durable darkening agent for fabric according to claim 1, characterized in that: The aqueous adhesive is one or more of silica hydrosol, poly(glycidyl methacrylate)-b-polyethylene glycol monomethyl ether monomethacrylate, poly(glycidyl methacrylate)-b-polyethylene glycol monomethyl ether monomethacrylate-b-poly(hexafluorobutyl methacrylate), and poly(n-butyl acrylate)-b-polyacrylic acid emulsion.

3. The method for preparing a durable darkening agent for fabric according to claim 1, characterized in that: The size of porous silica particles is 30-100 nm.

4. A durable darkening agent for fabric according to any one of claims 1 to 3, characterized in that: The porous silica particle dispersion is a mesoporous silica particle dispersion or a hollow silica particle dispersion.

5. A durable darkening agent for fabric according to claim 4, characterized in that: The mesoporous silica particle dispersion is prepared by the following method: Hexadecyltrimethylammonium chloride, sodium acetate trihydrate and deionized water are mixed, and the resulting mixture is vigorously stirred at 65-75°C for 20-40 min; then tetraethoxysilane is added, and the stirring reaction is continued for 6-20 h to obtain a milky white uniformly dispersed mesoporous silica dispersion; the dispersion is centrifuged and washed several times and then redispersed in water to obtain a mesoporous silica particle dispersion.

6. A durable darkening agent for fabric according to claim 5, characterized in that: The method also comprises a mixture of mesitylene, hexadecyltrimethylammonium chloride, sodium acetate trihydrate, mesitylene and deionized water.

7. A durable darkening agent for fabric according to claim 4, characterized in that: The hollow silica particle dispersion is prepared by the following method: an ammonia solution containing polyacrylic acid is mixed with ethanol, and then tetraethoxysilane is injected into the mixture several times at room temperature and under strong stirring conditions, with an interval of 1 to 3 hours each time, and stirring is continued for 5 to 15 hours to obtain a milky white dispersion, and then the dispersion is centrifuged and washed several times to remove the polyacrylic acid, and then redispersed in water to obtain a hollow silica dispersion.

8. A method for preparing a durable darkening agent for fabrics, characterized in that: The porous silica particle dispersion and the aqueous adhesive are mixed and added into a reaction container, and stirred at a speed of 500 to 1500 rpm for 10 to 80 minutes at room temperature to obtain a uniformly dispersed durable darkening agent for fabrics.

9. The durable darkening agent for fabrics according to claim 1 is used for textile finishing.

Images