Acid fixing agent and its preparation method and applications

Abstract

This invention relates to a method for preparing an acidic fixing agent, comprising the following steps: (a) providing a polyphenolic compound and an aldehyde compound, wherein the polyphenolic compound does not contain bisphenol A, bisphenol S, bisphenol F, bisphenol AF, or other endocrine disrupting substances; (b) mixing the polyphenolic compound and the aldehyde compound in a solvent at a molar ratio of 5-1.2:1; (c) adding an acidic catalyst and heating to 70-145°C for 3-5 hours; (d) cooling to room temperature and adding deionized water and / or sodium hydroxide to adjust the pH to 2.0-4.0; and (e) filtering the product of (d) to obtain the acidic fixing agent. This invention further relates to a method for post-treatment of dyed fabrics using this acidic fixing agent.

Claims

1. A method for preparing an acidic fixing agent, comprising: (a) providing a polyphenolic compound and an aldehyde compound, wherein the polyphenolic compound does not include bisphenol A, bisphenol S, bisphenol F, bisphenol AF, or other endocrine disrupting substances; (b) mixing the polyphenolic compound and the aldehyde compound in a molar ratio of 5-1.2:1 in a solvent; (c) adding an acidic catalyst and heating to 70-145°C for 3-5 hours; (d) cooling to room temperature and adding deionized water and / or sodium hydroxide to adjust the pH to 2.0-4.0; (e) filtering the product of (d) to obtain the acidic fixing agent.

2. A method for preparing an acidic fixing agent, comprising: (a) providing a polyphenolic compound and an aldehyde compound, wherein the polyphenolic compound does not include bisphenol A, bisphenol S, bisphenol F, bisphenol AF, or other endocrine disrupting substances; (b) mixing the polyphenolic compound with an acidic catalyst in a solvent and heating to 70-145°C for 3-5 hours; (c) adding the aldehyde compound, wherein the molar ratio of the polyphenolic compound to the aldehyde compound is 5-1.2:1; (d) cooling to room temperature and adding deionized water and / or sodium hydroxide to adjust the pH to 2.0-4.0; (e) filtering the product of (d) to obtain the acidic fixing agent.

3. The method as described in claim 1 or 2, wherein the polyphenolic compound comprises phenol, p-cresol, o-cresol, 2,4-di-tert-butylphenol, α-naphthol, hydroquinone, resorcinol, catechol, 4,4'-biphenyl, 4,4'-dihydroxybiphenylmethane, gallic acid, pyrogallol, pentahydroxybenzene, trihydroxybenzoic acid, catechin, proanthocyanidins, tannic acid, guaiacol, eugenol, cardanol, lignin or its degradation products, hydrolyzed lignin phenols, polyhydroxyphenoxy esters, resin phenols or combinations thereof.

4. The method as described in claim 1 or 2, wherein the aldehyde compound comprises formaldehyde, acetaldehyde, propionaldehyde, isobutyraldehyde, isovaleraldehyde, glyoxal, glutaraldehyde, sebacaldehyde, trioxymethylene, paraformaldehyde, p-hydroxybenzaldehyde, m-hydroxybenzaldehyde, salicylaldehyde, vanillin, cinnamaldehyde, benzaldehyde, o-methoxybenzaldehyde, acrolein, crotonaldehyde, pentahydroxymethylfurfural (HMF), furfural, aldehyde-modified polysaccharides, aldehyde-modified polyethylene glycol, or combinations thereof.

5. The method as described in claim 1 or 2, wherein the molar ratio of the polyphenol to the acid catalyst is 3:1 to 1:

2.

6. The method as described in claim 1 or 2, wherein the acid catalyst is concentrated sulfuric acid or fuming sulfuric acid.

7. The method as described in claim 1 or 2, wherein the solvent is acetic anhydride, acetic acid, or a high-boiling-point alcohol.

8. The method as described in claim 1 or 2, wherein the acidic fixing agent is free of bisphenol A, bisphenol S, bisphenol F, bisphenol AF, free formaldehyde and other endocrine disrupting substances.

9. The method as described in claim 1 or 2, wherein the acidic fixing agent is suitable for fixing leather, wool, silk, synthetic fibers or combinations thereof.

10. An acidic fixing agent prepared by any one of claims 1-9.

11. A method for post-treatment of dyed fabric, comprising the following steps: (a) immersing the dyed fabric in an acidic fixing agent as described in claim 10; (b) controlling the pH of the acidic fixing agent to 2.0–4.0, the immersion temperature to 70–90°C, and the immersion time to 10–30 minutes; and (c) washing and drying the dyed fabric.

12. The method as described in claim 11, wherein the material of the dyed fabric includes leather, wool, silk, synthetic fibers, or combinations thereof.

13. The method as described in claim 11, wherein the dye used to dye the fabric is a highly saturated acid dye.

14. The method as described in claim 11, wherein the results of the AATCC and ISO wash fastness tests of the dyed fabric after post-treatment are both higher than or equal to grade 4.

15. The method as described in claim 11, wherein the ΔE color difference value between the post-treated dyed fabric and the untreated dyed fabric is less than 3.