Environment-friendly acidic color fixing agent

Abstract

The invention relates to the technical field of color fixing agents, and discloses an environment-friendly acidic color fixing agent which is obtained by designing and synthesizing a novel monomer structure and further synthesizing resin through condensation. The bisphenol-free environment-friendly acidic color fixing agent comprises an F-type acidic color fixing agent and an E-type acidic color fixing agent; according to the invention, the resin formed by condensation polymerization of monomers has a synergistic effect with a compound system of potassium sorbate, buffer pairs and caprolactam, so that the defects of single color fixing resin in stability and compatibility are microcosmically overcome. The buffer pair maintains a stable pH environment, so that the interaction efficiency of the resin, the dye and the fiber is guaranteed; the compatibility of caprolactam is improved, so that the resin forms a uniform and compact film layer on the surface of the fiber, the film layer falling in washing and perspiration environments is reduced, the comprehensive color fastness of washing resistance, perspiration resistance, water soaking resistance and the like is synergistically improved, and the one-sidedness of performance under a single characteristic is avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fixing agents, in particular to an environmentally friendly acid fixing agent. BACKGROUND

[0002] Acid fixing agent is a core auxiliary agent for protein fibers such as nylon, wool, silk, etc. in the field of textile printing and dyeing. Its core function is to form insoluble lake with acid dye molecules or film on the surface of the fiber, thereby improving the color fastness to washing, color fastness to perspiration and color fastness to rubbing of the fabric, and directly affecting the use performance and market acceptance of the textile. With the upgrading of global environmental awareness and the increasingly stringent regulations, the textile industry has high requirements for the environmental friendliness and functionality of acid fixing agents. However, the existing technology has significant technical bottlenecks: The development of acid fixing agents has gone through two main stages of natural tannin-tartaric acid two-bath method and synthetic tannins, but both have problems that are difficult to overcome: Although the natural tannin-tartaric acid two-bath method has acceptable fixing effect, it has a complicated process and high production cost, and the fabric after treatment has rough hand feeling and obvious color change, which cannot meet the needs of large-scale production and high-quality fabrics; The synthetic tannin fixing agent developed later is composed of bisphenol A (BPA), bisphenol S (BPS), bisphenol F (BPF) and formaldehyde (such as patent CN202011276043.4). Although the process is simplified and the fixing effect is excellent (the soaping fastness can reach 4-5 levels), bisphenols as typical endocrine disruptors can accumulate through the food chain to interfere with the hormone balance of living organisms, and have been proven to cause toxic effects such as abnormal embryonic development of seawater guppy fish, decreased spawning rate of adult fish, and abnormal proliferation of mammary gland cells in mammals.

[0003] Currently, global regulations on bisphenol substances are becoming increasingly stringent: BPA and BPS are listed in the EU REACH regulation as substances of very high concern (SVHC), and (EU) 2024 / 3190 bans their use in food contact materials, with a limit of 1 μg / kg; OEKO-TEX®100 standard requires that the residual bisphenol S in textiles be less than 1000 ppm, and high-end brands have even stricter requirements of 200 ppm or even 1 ppm, so traditional bisphenol fixing agents have completely failed to meet the compliance requirements.

[0004] To cope with the restriction of bisphenol substances, three types of alternative solutions developed by the industry all have obvious performance or application defects, and have failed to achieve a synergistic improvement in environmental friendliness and functionality: Low bisphenol residual fixing agent (such as patent CN202311470566.6) controls the residual of bisphenol S to below 1000 ppm through process optimization, but does not eliminate the risk of toxicity from the root, and the fixing fastness is 10-15% lower than that of traditional products, which is difficult to match the core performance requirements of textiles; Bio-based substitutes (such as patent CN202411501257.5) use natural raw materials such as cardanol and plant polyphenols, which achieve no bisphenol residue, but the source of raw materials is limited (low yield of cashew nut shell oil), and the fixing efficiency is insufficient, with only 3 levels of soaping fastness, which cannot meet the durability requirements of high-end textiles; Nanocomposites (such as patent CN202410023353.2) construct multi-anchor structures by modifying nano-SiO2, which improves the fixing effect, but the synthesis process is complex (Pickering emulsion interfacial polymerization is required), the production cost is 3-4 times that of traditional products, and the scale application is extremely difficult, and it is only suitable for light-colored fabrics, with narrow application range.

[0005] With the implementation of the EU regulation banning bisphenol substances in 2025, and the upgrading of brand demand for green textiles, it is an urgent need for the industry to develop an acid fixing agent that is "completely free of bisphenol, formaldehyde and other restricted substances, and has fixing performance comparable to traditional products". The existing bisphenol-free fixing agent generally has low fixing efficiency (such as bio-based product with only 2-3 levels of water resistance), narrow application range, high production cost or limited raw materials, etc. The core problem is that the molecular structure design and process route fail to achieve the synergy of environmental protection and functionality. Therefore, further improvement is needed to solve the corresponding technical problems. SUMMARY

[0006] In view of the problems in the prior art, the present application provides an environmentally friendly acid fixing agent.

[0007] The technical solution adopted by the present application to solve its technical problems is: an environmentally friendly acid fixing agent without bisphenol, which is synthesized by designing a new monomer structure and further condensing into a resin; The bisphenol-free environmentally friendly acid fixing agent includes: F-type acid fixing agent and E-type acid fixing agent; The monomer has the following structural general formula:

[0008] Among them, R1 is a linear or branched alkyl group with 1-6 carbon atoms; R2 is a linear or branched alkyl group with 1-6 carbon atoms or H; R3 is H, OH, COOH, COOCH3, NH3; R4 is one of S, N, and C; R5 is a saturated or unsaturated heterocycle, including but not limited to morpholine, piperidine, pyrrolidine, tetrahydrofuran, morpholine, thiolane, piperazine, pyridine, pyrrole, furan, thiophene, imidazole, purine, etc.

[0009] As a further technical solution, the F-type acid fixing agent has the following general structure:

[0010] n is 5-20; R1 is a C1-C6 linear or branched alkyl group; R2 is a C1-C6 linear or branched alkyl group or H; R3 is H, OH, COOH, COOCH3, NH3.

[0011] As a further technical solution, the preparation method of the F-type acid fixing agent comprises: (1) Synthesis of monomers: using o-cresol and sodium p-hydroxybenzenesulfonate as raw materials, monomers are synthesized under the catalysis of an acid catalyst, Eaton reagent or oxalyl chloride, and the reaction is monitored by HPLC. (2) Synthesis method of acid fixing agent: the above monomers are added to an acid anhydride solution and stirred, then dilute sulfuric acid is slowly added, heated to about 100°C, and stirred for 4-6h; then cooled to room temperature, diluted with deionized water, then added 37% formaldehyde solution, heated to 100°C, stirred for 5-8h, cooled, added 30% sodium hydroxide solution, adjusted pH to 4-5, and finally compounded to obtain the F-type acid fixing agent.

[0012] As a further technical solution, the acid anhydride is acetic anhydride.

[0013] As a further technical solution, the E-type acid fixing agent has the following general structure: 、

[0014] n is 5-20; R4 is one of S, N, C, etc. R5 is a saturated or unsaturated heterocycle, including but not limited to morpholine, piperidine, pyrrolidine, tetrahydrofuran, morpholine, thiolane, piperazine, pyridine, pyrrole, furan, thiophene, imidazole, purine.

[0015] As a further technical solution, the preparation method of the E-type acid fixing agent comprises: (1) Synthesis of monomers: using o-cresol and sodium p-hydroxybenzenesulfonate as raw materials, monomers are synthesized under the catalysis of an acid catalyst, Eaton reagent or oxalyl chloride, and the reaction is monitored by HPLC.

[0016] (2) The synthesis method of the acid fixing agent: the monomer synthesized above, sodium p-hydroxybenzenesulfonate and aldehyde substances are pre-polymerized and further condensed under acidic or alkaline conditions to obtain a resin, and finally a E-type acid fixing agent is obtained by compounding.

[0017] As a further technical solution, the aldehyde substance is a formaldehyde solution with a mass fraction of 37%; the temperature of the condensation reaction is 110-130 DEG C, and the reaction time is 8-15 h.

[0018] As a further technical solution, the components and mass ratio added in the compounding process are: 0.1-0.3% potassium sorbate, 1-3% triethanolamine-acetic acid buffer pair, and 4-6% caprolactam.

[0019] The beneficial effects of the present application are: 1. The present application realizes the synergistic improvement of environmental protection, functionality and industrial feasibility through the design of a new monomer structure, the optimization of a mild synthesis process and the construction of a precise compounding system.

[0020] 2. Microscopic environmental protection and fixing effect of the new monomer structure: the innovatively designed aromatic sulfonic acid monomer (containing specific alkyl, heterocyclic substituent) completely abandons the introduction of bisphenol substances from the molecular structure, avoids the production of endocrine disruptors microscopically, makes the product completely free of harmful substances such as phenol, BPS and BPF, and meets the stringent environmental protection standards such as blue standard, ZDHC, OEKO-TEX Standard 100, etc.; at the same time, the heterocyclic ring (morpholine, piperidine, etc.) in the monomer structure forms multiple anchoring sites with the sulfonic acid group, which can form strong interaction with the acid dye molecule microscopically, and form stable combination with the protein fiber surface hydroxyl and amino group, laying a molecular foundation for high color fastness.

[0021] 3. In the present application, mild catalyst systems such as acid catalyst, Eaton reagent or oxalyl chloride are used, combined with step-by-step polycondensation process, the reaction conditions are easy to control microscopically (reaction temperature 80-120 DEG C, reaction time 4-15 h), avoiding harsh conditions such as high temperature and high pressure, reducing energy consumption and equipment loss; the raw materials are easily available chemical raw materials such as o-cresol and sodium p-hydroxybenzenesulfonate, which microscopically reduces the dependence on special raw materials, reduces the raw material procurement cost, and the process has no complex intermediate steps, which microscopically improves the reaction conversion rate and reduces the generation of by-products. The potassium sorbate in the compounding system microscopically plays a role in preventing corrosion and preservation, prolonging the shelf life of the product; the triethanolamine-acetic acid buffer pair can accurately adjust the pH of the system to 4-5, microscopically maintaining the stability of the acidity and alkalinity during the fixing process, avoiding fiber damage and color change; caprolactam microscopically enhances the compatibility of the fixing agent and the fiber, improves the adhesion of the film layer, and further optimizes the rubbing resistance and perspiration resistance.

[0022] 4. The resin formed by monomer condensation in this invention, in conjunction with the compound system of potassium sorbate, buffer pairs, and caprolactam, works synergistically to address the shortcomings of single color-fixing resins in terms of stability and compatibility at the microscopic level. The stable pH environment maintained by the buffer pairs ensures the efficiency of the interaction between the resin, dye, and fiber; the improved compatibility of caprolactam allows the resin to form a uniform and dense film on the fiber surface, reducing film peeling under washing and perspiration conditions, and synergistically improving the overall color fastness, including wash resistance, perspiration resistance, and water immersion resistance, avoiding the one-sidedness of performance under a single characteristic. Attached Figure Description

[0023] Figure 1 This is the hydrogen NMR spectrum of D-1. Figure 2 This is the carbon NMR spectrum of D-1. Figure 3 This is the hydrogen NMR spectrum of D-2; Figure 4 This is the carbon NMR spectrum of D-2. Figure 5 This is the hydrogen NMR spectrum of D-3. Figure 6 This is a carbon NMR spectrum of D-3. Detailed Implementation

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1. Synthesis method of D-1 monomer: 43.2 g (1 eq) of o-cresol, 20 g (0.5 eq) of 98% concentrated sulfuric acid, and 20 ml (40 ml added later) of monochlorobenzene were placed in a reaction vessel equipped with a stirrer, condenser, and water separator. The reaction mixture was heated to reflux temperature, with reflux beginning at approximately 130°C. The chlorobenzene and water vapors formed during the reaction were condensed, collected, and separated in the water separator.

[0026] At the end of the reaction, 10 g of water was slowly added to the reaction product, followed by 3.2 g of 50% sodium hydroxide solution. Then, 40 g of water was added, and chlorobenzene was removed by azeotropic distillation. After all chlorobenzene was removed, the reaction product, in the form of brick-red crystals, was separated from the water by washing with water and filtering. It was then dried in an oven to obtain approximately 35 g of D-1.

[0027] ; NMR spectral data:1H NMR (400MHz, DMSO) δ 7.59 (t, J = 4.4 Hz, 2H), 7.56 (dd, J = 8.4, 2.4 Hz, 2H), 6.92 (dd, J = 8.5, 5.5 Hz, 2H), 2.14 (s, 6H); 13C NMR (101MHz, DMSO) δ 160.14, 130.78, 129.94, 128.14, 127.19, 126.70, 125.77, 115.23, 16.29; Synthesis method of acidic color fixing agent F-1: D-1 (35g) was added to a solution of acetic anhydride (46g), stirred, then diluted sulfuric acid was slowly added, heated to about 100°C, and stirred for 6h; then cooled to room temperature, diluted with 10ml of water, then added 10g of formaldehyde solution, heated to 100°C, stirred for 5h-10h, cooled, added appropriate amount of 30% sodium hydroxide solution, adjusted pH = 4-5, then added 0.2% potassium sorbate, 2% triethanolamine-acetic acid buffer and 5% caprolactam.

[0028] Example 2. Synthesis method of D-2 monomer: First, configure Eaton's reagent (Eaton's reagent), mix phosphorus pentoxide and methane sulfonic acid according to the mass ratio of 1:10, and stir to obtain a mixed solution.

[0029] Then, 20g of sodium p-hydroxybenzenesulfonate (1eq) and 12.4g of o-cresol (1eq) were weighed, 20g of Eaton's reagent was used as a solvent and a catalyst, and the mixture was stirred and reacted at 80°C. TLC monitoring, after the reaction was completed, the mixture was poured into ice water, and the precipitate was extracted with ethyl acetate, and dried to obtain.

[0030] ; NMR spectral data:1H NMR (400MHz, DMSO) δ 7.73–7.62 (m, 1H), 7.59 (t, J = 4.2 Hz, 2H), 7.56 (dd, J = 8.4, 2.4 Hz, 2H), 6.99–6.82 (m, 2H), 2.14 (s, 3H); 13C NMR (101MHz, DMSO) δ 160.06, 132.41, 130.78, 129.93, 128.14, 127.10, 125.75, 116.22, 16.28; Synthesis method of acidic color fixing agent F-2: D-2 (35 g) was added to a solution of acetic anhydride (46 g), stirred, then slowly added dilute sulfuric acid, heated to about 100°C, stirred for 6 h; then cooled to room temperature, diluted with 10 ml of water, then added 10 g of formaldehyde solution, heated to 100°C, stirred for 5-10 h, cooled, added an appropriate amount of 30% sodium hydroxide solution, adjusted to pH = 4-5, then added potassium sorbate 0.2%, triethanolamine-acetic acid buffer 2% and caprolactam 5% complex.

[0031] Similarly, the synthesis method of the acid fixing agent of other F class monomers is as above.

[0032] Synthesis method of acid fixing agent E class monomer: Example 3. Synthesis method of D-3 monomer: Synthesis of sulfonyl chloride: Sodium 4-hydroxybenzenesulfonate (7 g) was added to a reaction bottle, DCM (60 ml) was added as a solvent, oxalyl chloride (14.8 ml) was slowly added dropwise, 2 drops of DMF were added as a catalyst after the dropwise addition was completed, bubbles were generated, a balloon was put on to receive the generated gas, at this time it was a white turbid liquid, TLC monitoring, after the reaction was completed, the reaction was dried, and the solvent was directly used for the next step reaction.

[0033] The 4-hydroxybenzenesulfonyl chloride (6.2 g) obtained in the above step was added to morpholine (2.5 ml), DCM (50 ml) was used as a solvent, pyridine (6.8 g) was added dropwise as a base catalyst, and the reaction was stirred at room temperature overnight, TLC monitoring; Post-treatment: add an appropriate amount of water, extract with DCM, wash with saturated sodium chloride solution, dry over anhydrous magnesium sulfate for 30-60 min, filter and concentrate to obtain 6.5 g of light yellow product.

[0034] ; NMR spectrum data:1H NMR (400 MHz, DMSO) δ 7.55 (d, J = 8.7 Hz, 2H), 6.97 (d, J = 8.7 Hz, 2H), 3.66-3.58 (m, 4H), 2.81 (dd, J = 8.0, 3.2 Hz, 4H); 13C NMR (101 MHz, DMSO) δ 162.71, 130.47, 124.14, 116.25, 66.62, 65.50, 51.79, 6.34; The synthesis method of other E class monomers is referred to D-3.

[0035] Synthesis method of acid fixing agent E-3: Into a reaction bottle, 12.8 g of D-3 (0.8 eq), 10.7 g of sodium p-hydroxybenzenesulfonate (1.5 eq), 11 g of 32% liquid alkali (2 eq), and 35 g of deionized water are sequentially added, stirred, 37% formaldehyde solution (0.8 eq) is added, then the temperature is raised to 120°C for 8-15 h, 0.2% potassium sorbate is added, citric acid is added to adjust the pH to 4.0, and 5% caprolactam is added to obtain a compound.

[0036] The other compounds of class E are prepared in the same way.

[0037] Performance test method: Bath ratio 1:10, 80°C x 20 min, water washing, dehydration, 100°C drying, water bubble fastness test (bath ratio 1:50, Tide laundry powder 2 g / L, 80°C water room temperature soaking for 5 min, comparison of color fading), color fastness to washing (GB / T3921C-2008 method), alkali fastness to perspiration (GB / T3922-2013 method); Performance test results: Water bubble fastness: The water bubble fastness of the examples is shown in Table 1, the alkali fastness to perspiration of Example 1 is shown in Table 2, and the color fastness to washing of Example 1 is shown in Table 3: Table 1: Test results of water washing fastness of fabrics treated with different fixing agents

[0038] Table 2: Test results of alkali fastness to perspiration of Example 1

[0039] Table 3: Test results of color fastness to washing of Example 1

[0040] From the test results in Tables 1, 2, and 3, it can be seen that Examples 1-3 provided by the present application have good water washing fastness, and the water washing fastness is all above 4 / 4-5 levels at a concentration of 4% (o.w.f), which is significantly higher than that of market samples. Example 1 has good alkali fastness to perspiration and color fastness to washing, and the water washing fastness is all above 4 levels at a concentration of 4% (o.w.f), which is significantly higher than that of market samples.

[0041] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements, and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. An acidic, environmentally friendly color-fixing agent, characterized in that, By designing and synthesizing novel monomer structures, and further condensing them into resins, an environmentally friendly acidic color-fixing agent without bisphenols was obtained. The bisphenol-free environmentally friendly acidic color-fixing agents include: type F acidic color-fixing agents and type E acidic color-fixing agents; The monomer has the following general structural formula: ； Wherein, R1 is a straight-chain or branched alkyl group of C1 to C6; R2 is a C1-C6 straight-chain or branched alkyl group or H; R3 can be H, OH, COOH, COOCH3, or NH3; R4 is one of S, N, or C; R5 is a saturated or unsaturated heterocycle, including but not limited to morpholine, piperidine, pyrrolidine, tetrahydrofuran, morpholine, thiocyclopentane, piperazine, pyridine, pyrrole, furan, thiophene, imidazole, purine, etc.

2. The acidic environmentally friendly color-fixing agent according to claim 1, characterized in that, The F-type acidic fixing agent has the following general structural formula: ； Where n is 5-20; R1 is a C1-C6 straight-chain or branched alkyl group; R2 is a C1-C6 straight-chain or branched alkyl group or H; R3 can be H, OH, COOH, COOCH3, or NH3.

3. The acidic environmentally friendly color-fixing agent according to claim 2, characterized in that, The preparation method of the F-type acidic fixing agent includes: (1) Synthesis of monomers: Using o-cresol and sodium p-hydroxybenzenesulfonate as raw materials, monomers are synthesized under the catalysis of acidic catalyst, Eaton reagent or oxalyl chloride, and the reaction is monitored by HPLC; (2) Synthesis method of acidic fixing agent: The above monomers are added to the acid anhydride solution and stirred. Then dilute sulfuric acid is slowly added and heated to about 100°C. The reaction is stirred for 4-6 hours. Then the temperature is cooled to room temperature, deionized water is added for dilution, and then 37% formaldehyde solution is added. The temperature is heated to 100°C and stirred for 5-8 hours. After cooling, 30% sodium hydroxide solution is added to adjust the pH to 4-5. Finally, the F-type acidic fixing agent is obtained by compounding.

4. The acidic environmentally friendly color-fixing agent according to claim 3, characterized in that, The acid anhydride is acetic anhydride.

5. The acidic environmentally friendly color-fixing agent according to claim 1, characterized in that, The E-type acidic fixing agent has the following general structural formula: 、 ； Where n is 5-20; R4 is one of S, N, C, etc.; R5 is a saturated or unsaturated heterocycle, including but not limited to morpholine, piperidine, pyrrolidine, tetrahydrofuran, morpholine, thiocyclopentane, piperazine, pyridine, pyrrole, furan, thiophene, imidazole, and purine.

6. The acidic environmentally friendly color-fixing agent according to claim 5, characterized in that, The preparation method of the E-type acidic fixing agent includes: (1) Synthesis of monomers: Using o-cresol and sodium p-hydroxybenzenesulfonate as raw materials, monomers are synthesized under the catalysis of acidic catalyst, Eaton reagent or oxalyl chloride, and the reaction is monitored by HPLC; (2) Synthesis method of acidic fixing agent: The monomer synthesized above, sodium p-hydroxybenzenesulfonate and aldehyde substances are prepolymerized and further condensed under acidic or alkaline conditions to obtain resin, and finally compounded to obtain E-type acidic fixing agent.

7. The acidic environmentally friendly color-fixing agent according to claim 6, characterized in that, The aldehyde is a formaldehyde solution with a mass fraction of 37%; the condensation reaction temperature is 110-130℃, and the reaction time is 8-15h.

8. An acidic environmentally friendly color-fixing agent according to any one of claims 3-6, characterized in that, The components added during the compounding process and their mass percentages are as follows: 0.1-0.3% potassium sorbate, 1-3% triethanolamine-acetic acid buffer pair, 4-6% caprolactam.

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