CN103603197A - Method for improving dyeing property of superfine fiber synthetic leather base cloth - Google Patents

Abstract

A method for improving the dyeing performance of superfine fiber synthetic leather base cloth, adding water to gelatin, stirring to swell the gelatin to obtain a gelatin solution, adding alkaline protease to the gelatin solution for hydrolysis; adding superfine fiber synthetic Leather base cloth, using acid to treat the ultra-fine fiber synthetic leather base cloth to obtain surface modified ultra-fine fiber synthetic leather base cloth; add collagen to the drum, and graft and modify the collagen to the surface modified The superfine fiber synthetic leather base cloth is reacted to obtain the collagen modified superfine fiber synthetic leather base cloth; the dye is added to the drum to dye the collagen modified superfine fiber synthetic leather base cloth. The invention utilizes collagen to modify the base cloth of ultra-fine fiber synthetic leather, realizes the covalent modification of collagen to the base cloth of ultra-fine fiber synthetic leather, and then effectively improves the dyeing performance of the ultra-fine fiber synthetic leather, making the Its dyeing rate is as high as 94.21%, which is beneficial to the development of the superfine fiber synthetic leather industry.

Description

A method for improving the dyeing performance of superfine fiber synthetic leather base cloth

technical field

The invention belongs to the technical field of application of superfine fiber synthetic leather, and in particular relates to a method for improving the dyeing performance of superfine fiber synthetic leather base cloth.

Background technique

Superfine fiber synthetic leather is a high-grade synthetic leather similar to natural leather made of polyamide superfine fiber as the matrix layer and polyurethane as the elastomer. The structure of the polyamide superfine fiber is similar to that of natural leather protein collagen fibers. PU moisture-permeable polyurethane resin has high durability and is a new field with great potential and good development prospects.

Polyamide microfibers contain very few active groups, and only contain carboxyl and amino groups at the end of the molecular chain. There are a large number of carbon chains and amide bonds on the molecular chain, but there are no side chains. Therefore, when dyeing superfine fiber synthetic leather, it is mainly Relying on the physical combination of the dye itself to color the fiber, most dyes are difficult to dye, and the color fastness of the dyed product is poor, and the superfine fiber is very fine, the specific surface area is large, and the amount of dye consumed during dyeing is large. In addition, microfiber synthetic leather is a kind of composite material. There is a big difference in the dyeing properties of polyamide microfiber and polyurethane. It is difficult to meet the dyeing requirements of the two components at the same time by using a single dye and a single dyeing method, and cannot achieve good dyeing properties. Dyeing effect, so it is necessary to study the method of improving the dyeing performance of superfine fiber synthetic leather.

In response to the above problems, many researchers have explored and studied the modification of ultrafine fiber synthetic leather in recent years. The most effective method is to try to introduce active groups into ultrafine fiber synthetic leather to improve the dyeing of ultrafine fiber synthetic leather. performance. Through a certain chemical modification, the active groups on the base cloth are increased, and the dye binding points are increased, thereby improving the dyeing performance of the superfine fiber synthetic leather. At present, researchers have mainly conducted research on dyes used for dyeing, dyeing conditions, chemical modification, and additives. Although many achievements have been made, there is still a big gap from industrial production. A method for the dyeing properties of fiber synthetic leather is necessary.

Gelatin is an amphoteric, non-toxic natural biomass polymer substance. The collagen produced after hydrolysis is a typical amphoteric polyelectrolyte, which contains a large number of active groups such as amino and carboxyl groups. It is hydrophilic and biocompatible. Good resistance and degradation performance. As a big country in the tanning industry, my country produces a large amount of discarded leather scraps every year. Extracting and utilizing the gelatin in the discarded leather scraps can save resources, reduce environmental pollution, and realize the resource utilization of discarded leather scraps.

Contents of the invention

The purpose of the present invention is to provide a method for improving the dyeing performance of the ultrafine fiber synthetic leather base cloth, by increasing the active groups on the ultrafine fiber synthetic leather base cloth, and then improving the dyeing performance of the ultrafine fiber synthetic leather base cloth.

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

The present invention comprises the following steps:

1) Preparation of collagen:

Add water to the gelatin, stir to swell the gelatin to obtain a gelatin solution with a mass concentration of 20% to 40%, adjust the pH of the gelatin solution to 8.0 to 10.0, and then add alkaline protease to the gelatin solution at 40 to 60°C Stir and hydrolyze for 2-6 hours to obtain collagen; among them, the amount of alkaline protease accounts for 0.8%-2.0% of the mass of gelatin;

2) Pretreatment of microfiber synthetic leather base cloth:

Add microfiber synthetic leather base cloth into the drum, and use acid to treat microfiber synthetic leather base cloth for 2 to 5 hours under the condition of liquid ratio of 3000% to 6000% and temperature of 35 to 55°C to obtain surface Modified superfine fiber synthetic leather base cloth; wherein, the amount of acid accounts for 10% to 20% of the mass of the superfine fiber synthetic leather base cloth;

3) Collagen modification of superfine fiber synthetic leather base cloth:

Under the conditions of liquid ratio of 2000% to 5000%, pH value of 2.0 to 9.0, and temperature of 20 to 60°C, add collagen to the drum in step 2) to graft and modify the collagen to surface modification On the superfine fiber synthetic leather base cloth, react for 0.5 ~ 4h to obtain the collagen modified superfine fiber synthetic leather base cloth; the amount of collagen is 4% to 20% of the surface modified superfine fiber synthetic leather base cloth %;

4) Dyeing of collagen modified superfine fiber synthetic leather base cloth:

Under the condition that the liquid ratio is 2000%-5000%, the pH value is 4.5-5.5, and the temperature is 50-60°C, add dyes to the drum in step 3) to dye the collagen-modified superfine fiber synthetic leather base cloth After 1-4 hours, a dyed superfine fiber synthetic leather base cloth is obtained; wherein the amount of the dye is 1% to 8% of the mass of the collagen modified superfine fiber synthetic leather base cloth.

The gelatin in the step 1) is extracted from waste leather scraps.

The pH value in step 1) is adjusted with sodium hydroxide solution.

The acid in step 2) is concentrated sulfuric acid with a mass fraction of 98% or analytically pure formic acid.

The pH value in step 3) is adjusted with sodium hydroxide solution or dilute sulfuric acid.

In step 3), before adding collagen to the drum, add a crosslinking agent and react for 0.5-4 hours. The amount of crosslinking agent added accounts for 1%-18% of the mass of the surface-modified ultrafine fiber synthetic leather base cloth.

The crosslinking agent is tanning agent F-90 or tanning agent TWT.

The pH value in step 4) is adjusted with dilute sulfuric acid.

The dyes in step 4) are acid dyes or reactive dyes.

The present invention has the following advantages: the present invention can expose some active groups on the surface of the base cloth by pretreating the ultrafine fiber synthetic leather base cloth; The covalent modification of the base fabric increases the active groups on the base fabric, that is, increases the binding points of the dyes, making the dyeing rate as high as 94.21%, effectively improving the dyeing performance of the superfine fiber synthetic leather.

Further, the gelatin in the present invention is extracted from waste leather shavings, and the extraction method is simple and low in cost, thus reducing environmental pollution, rationally utilizing waste, and realizing resource utilization of waste leather shavings.

Before adding collagen, add a cross-linking agent into the drum for cross-linking reaction. The cross-linking agent is tanning agent F-90 or tanning agent TWT. The cross-linking agent can act as a bridge to introduce collagen into the superfine fiber synthetic leather. On the base fabric, thereby increasing the dye uptake rate of the base fabric and improving its dyeing performance.

Detailed ways

The present invention will be described in detail below in conjunction with specific embodiments.

The liquid ratio in the present invention refers to the mass ratio of water to the superfine fiber synthetic leather base cloth.

Example 1

1) Preparation of collagen:

Add water to the gelatin, stir to swell the gelatin to obtain a gelatin solution with a mass concentration of 20%, use 1mol/L sodium hydroxide solution to adjust the pH of the gelatin solution to 8.5, and then add alkaline to the gelatin solution at 50°C Protease was stirred and hydrolyzed for 5 hours to obtain collagen; wherein, the amount of alkaline protease accounted for 1.0% of the gelatin mass;

2) Pretreatment of microfiber synthetic leather base cloth:

Add microfiber synthetic leather base cloth into the drum, and use concentrated sulfuric acid with a mass fraction of 98% to treat the microfiber synthetic leather base cloth for 4.5 hours under the condition of liquid ratio of 3000% and temperature of 45°C to obtain Surface-modified superfine fiber synthetic leather base cloth; wherein, the consumption of concentrated sulfuric acid is 15% of the quality of superfine fiber synthetic leather base cloth;

3) Collagen modification of superfine fiber synthetic leather base cloth:

Under the condition that the liquid ratio is 2000%, the pH value is 4.0, and the temperature is 30°C, add collagen to the drum in step 2), and graft and modify the collagen onto the superfine fiber synthetic leather base cloth, and react 3h, obtain the collagen-modified microfiber synthetic leather base cloth; wherein, the pH value is adjusted by dilute sulfuric acid, and the consumption of collagen is 10% of the quality of the surface-modified superfine fiber synthetic leather base cloth;

4) Dyeing of collagen modified superfine fiber synthetic leather base cloth:

Under the condition that the liquid ratio is 5000%, the pH value is 4.5, and the temperature is 50°C, add acid dye (manufactured by Singapore DyStar Company) to the drum of step 3) to modify the collagen modified superfine fiber synthetic leather base. Cloth dyeing 1h, obtains the superfine fiber synthetic leather base cloth of dyeing; Wherein, pH value is to adopt dilute sulfuric acid to regulate, and the consumption of acid dye is 2.5% of the quality of collagen modified superfine fiber synthetic leather base cloth.

The dye uptake rate of superfine fiber synthetic leather base cloth reaches 84.78% in the present embodiment.

Example 2

1) Preparation of collagen:

Add water to the gelatin, stir to swell the gelatin to obtain a gelatin solution with a mass concentration of 40%, use 1mol/L sodium hydroxide solution to adjust the pH of the gelatin solution to 9.5, and then add alkaline to the gelatin solution at 60°C Protease was stirred and hydrolyzed for 4 hours to obtain collagen; wherein, the amount of alkaline protease accounted for 1.5% of the gelatin mass;

2) Pretreatment of microfiber synthetic leather base cloth:

Add microfiber synthetic leather base cloth into the drum, and use analytically pure formic acid to treat microfiber synthetic leather base cloth for 3.5 hours under the conditions of liquid ratio of 6000% and temperature of 55°C to obtain surface-modified Microfiber synthetic leather base cloth; wherein, the amount of formic acid is 12% of the mass of microfiber synthetic leather base cloth;

3) Collagen modification of superfine fiber synthetic leather base cloth:

Under the condition that the liquid ratio is 5000%, the pH value is 6.0, and the temperature is 40°C, add tanning agent F‐90 (manufactured by Clariant Chemical Materials Co., Ltd.) to the drum in step 2) to react for 0.5h, and then Add collagen, graft and modify the collagen onto the superfine fiber synthetic leather base cloth, and react for 5 hours to obtain the collagen modified superfine fiber synthetic leather base cloth; wherein, the pH value is adjusted by dilute sulfuric acid, and the tanning The consumption of agent F-90 is 15% of the surface-modified superfine fiber synthetic leather base cloth quality, and the consumption of collagen is 15% of the surface-modified superfine fiber synthetic leather base cloth quality;

4) Dyeing of collagen modified superfine fiber synthetic leather base cloth:

Under the conditions of liquid ratio of 2000%, pH value of 5.0, and temperature of 55°C, add reactive dyes (manufactured by Shanghai Shanpu Chemical Co., Ltd.) to the drum in step 3) to synthesize collagen-modified microfibers. The leather base cloth was dyed for 3h to obtain dyed superfine fiber synthetic leather base cloth; wherein, the pH value was adjusted by dilute sulfuric acid, and the consumption of reactive dye was 3.0% of the quality of the collagen modified superfine fiber synthetic leather base cloth.

The dye uptake rate of superfine fiber synthetic leather base cloth reaches 92.74% in the present embodiment.

Example 3

1) Preparation of collagen:

Add water to the gelatin, stir to swell the gelatin to obtain a gelatin solution with a mass concentration of 30%, use 1mol/L sodium hydroxide solution to adjust the pH of the gelatin solution to 9, and then add alkaline to the gelatin solution at 55°C Protease was stirred and hydrolyzed for 3 hours to obtain collagen; wherein, the amount of alkaline protease accounted for 2% of the gelatin mass;

2) Pretreatment of microfiber synthetic leather base cloth:

Add microfiber synthetic leather base cloth into the drum, and use analytically pure formic acid to treat microfiber synthetic leather base cloth for 2.5 hours under the conditions of liquid ratio of 4000% and temperature of 50°C to obtain surface-modified Microfiber synthetic leather base cloth; wherein, the amount of formic acid is 18% of the mass of microfiber synthetic leather base cloth;

3) Collagen modification of superfine fiber synthetic leather base cloth:

Under the conditions of liquid ratio of 3000%, pH value of 8.0, and temperature of 35°C, add tanning agent TWT (manufactured by Sichuan Tingjiang New Material Co., Ltd.) into the drum of step 2) to react for 4 hours, and then add Collagen, the collagen is grafted and modified onto the superfine fiber synthetic leather base cloth, and reacted for 3 hours to obtain the collagen modified superfine fiber synthetic leather base cloth; wherein, the pH value is determined by using 1mol/L sodium hydroxide solution Regulated, the consumption of tanning agent TWT is 18% of the superfine fiber synthetic leather base cloth quality of surface modification, and the consumption of collagen is 20% of the superfine fiber synthetic leather base cloth quality of surface modification;

4) Dyeing of collagen modified superfine fiber synthetic leather base cloth:

Under the condition that the liquid ratio is 3000%, the pH value is 5.5, and the temperature is 60°C, add acid dye to the drum in step 3) to dye the collagen modified ultrafine fiber synthetic leather base cloth for 2 hours, and obtain the dyed ultrafine fiber synthetic leather base cloth. Fine fiber synthetic leather base cloth; wherein, the pH value is adjusted by dilute sulfuric acid, and the amount of acid dye is 1.5% of the mass of the collagen modified superfine fiber synthetic leather base cloth.

The dye uptake rate of superfine fiber synthetic leather base cloth reaches 94.21% in the present embodiment.

Example 4

1) Preparation of collagen:

Add water to the gelatin, stir to swell the gelatin to obtain a gelatin solution with a mass concentration of 25%, adjust the pH of the gelatin solution to 8.0 with 1mol/L sodium hydroxide solution, and then add alkaline to the gelatin solution at 40°C Protease was stirred and hydrolyzed for 2 hours to obtain collagen; wherein, the amount of alkaline protease accounted for 0.8% of the gelatin mass;

2) Pretreatment of microfiber synthetic leather base cloth:

Add microfiber synthetic leather base cloth into the drum, and use concentrated sulfuric acid with a mass fraction of 98% to treat the microfiber synthetic leather base cloth for 2 hours at a liquid ratio of 3500% and a temperature of 40°C to obtain a surface Modified superfine fiber synthetic leather base cloth; wherein, the consumption of concentrated sulfuric acid accounts for 20% of the quality of superfine fiber synthetic leather base cloth;

3) Collagen modification of superfine fiber synthetic leather base cloth:

Under the condition that the liquid ratio is 2500%, the pH value is 9.0, and the temperature is 20°C, add collagen to the drum in step 2), and graft and modify the collagen onto the superfine fiber synthetic leather base cloth, and react 1h, obtain collagen modified superfine fiber synthetic leather base cloth; Wherein, pH value is to adopt 1mol/L sodium hydroxide solution to carry out, and the consumption of collagen is 18% of the surface modified superfine fiber synthetic leather base cloth quality. %;

4) Dyeing of collagen modified superfine fiber synthetic leather base cloth:

Under the condition that the liquid ratio is 3500%, the pH value is 5.5, and the temperature is 53°C, add reactive dyes to the drum in step 3) to dye the collagen modified ultrafine fiber synthetic leather base cloth for 4 hours, and obtain the dyed ultrafine fiber synthetic leather base cloth. Fine fiber synthetic leather base cloth; wherein, the pH value is adjusted by dilute sulfuric acid, and the amount of reactive dye is 8% of the mass of the collagen modified superfine fiber synthetic leather base cloth.

The dye uptake rate of superfine fiber synthetic leather base cloth reaches 89.21% in the present embodiment.

Example 5

1) Preparation of collagen:

Add water to the gelatin, stir to swell the gelatin to obtain a gelatin solution with a mass concentration of 35%, adjust the pH of the gelatin solution to 10.0 with 1mol/L sodium hydroxide solution, and then add alkaline to the gelatin solution at 45°C Protease was stirred and hydrolyzed for 4.5h to obtain collagen; wherein, the amount of alkaline protease accounted for 1.2% of the gelatin mass;

2) Pretreatment of microfiber synthetic leather base cloth:

Add microfiber synthetic leather base cloth into the drum, and use concentrated sulfuric acid with a mass fraction of 98% to treat the microfiber synthetic leather base cloth for 3.5 hours under the condition of liquid ratio of 5000% and temperature of 55°C to obtain Surface-modified superfine fiber synthetic leather base cloth; wherein, the consumption of concentrated sulfuric acid accounts for 13% of the quality of superfine fiber synthetic leather base cloth;

3) Collagen modification of superfine fiber synthetic leather base cloth:

Under the condition that the liquid ratio is 4500%, the pH value is 5.0, and the temperature is 60°C, add tanning agent F-90 to the drum in step 2) to react for 3 hours, and then add collagen to graft and modify the collagen to On the microfiber synthetic leather base cloth, react for 2 hours to obtain the collagen modified microfiber synthetic leather base cloth; wherein, the pH value is adjusted by dilute sulfuric acid, and the amount of tanning agent F-90 is the surface modified superfine fiber synthetic leather base cloth. 9% of the quality of the fine fiber synthetic leather base cloth, and the amount of collagen is 8% of the surface modified microfiber synthetic leather base cloth quality;

4) Dyeing of collagen modified superfine fiber synthetic leather base cloth:

Under the condition that the liquid ratio is 4500%, the pH value is 4.5, and the temperature is 58°C, add acid dye to the drum in step 3) to dye the collagen-modified microfiber synthetic leather base cloth for 2.5 hours to obtain dyed Superfine fiber synthetic leather base cloth; wherein, the pH value is adjusted by dilute sulfuric acid, and the amount of acid dye is 1% of the quality of the collagen modified superfine fiber synthetic leather base cloth.

The dye uptake rate of superfine fiber synthetic leather base cloth reaches 94.06% in the present embodiment.

Example 6

1) Preparation of collagen:

Add water to the gelatin, stir to swell the gelatin to obtain a gelatin solution with a mass concentration of 40%, adjust the pH of the gelatin solution to 8.0 with 1mol/L sodium hydroxide solution, and then add alkaline to the gelatin solution at 60°C Protease was stirred and hydrolyzed for 6 hours to obtain collagen; wherein, the amount of alkaline protease accounted for 1.8% of the gelatin mass;

2) Pretreatment of microfiber synthetic leather base cloth:

Add microfiber synthetic leather base cloth into the drum, and use analytically pure formic acid to treat microfiber synthetic leather base cloth for 5 hours under the conditions of liquid ratio of 4500% and temperature of 35°C to obtain surface-modified superfine fiber synthetic leather base cloth. Fine fiber synthetic leather base cloth; wherein, the amount of concentrated sulfuric acid accounts for 10% of the mass of the microfiber synthetic leather base cloth;

3) Collagen modification of superfine fiber synthetic leather base cloth:

Under the conditions of liquid ratio of 3500%, pH value of 2.0, and temperature of 50°C, add tanning agent TWT to the drum in step 2) to react for 2 hours, then add collagen to graft and modify collagen to ultrafine On the fiber synthetic leather base cloth, react for 1.5h to obtain the collagen modified ultrafine fiber synthetic leather base cloth; wherein, the pH value is adjusted by dilute sulfuric acid, and the amount of tanning agent TWT is the surface modified ultrafine fiber synthetic 1% of the mass of the leather base cloth, and the amount of collagen is 4% of the mass of the surface-modified microfiber synthetic leather base cloth;

4) Dyeing of collagen modified superfine fiber synthetic leather base cloth:

Under the condition that the liquid ratio is 2500%, the pH value is 5.0, and the temperature is 50°C, add reactive dyes to the drum in step 3) to dye the collagen-modified superfine fiber synthetic leather base cloth for 3.5 hours to obtain dyed Superfine fiber synthetic leather base cloth; wherein, the pH value is adjusted by dilute sulfuric acid, and the amount of reactive dye is 6% of the quality of the collagen modified superfine fiber synthetic leather base cloth.

The dye uptake rate of superfine fiber synthetic leather base cloth reaches 91.87% in the present embodiment.

The number average relative molecular mass of the collagen in the present invention is 800-1200, and the weight average relative molecular mass is 1200-1600. The gelatin used in Examples 1-6 is extracted from waste leather shavings, and the method is simple and low in cost.

The present invention can expose some active groups on the surface of the base cloth by pretreating the ultrafine fiber synthetic leather base cloth; covalently modify the ultrafine fiber synthetic leather base cloth by adopting alkaline protease to hydrolyze the gelatin prepared collagen It increases the active groups on the base cloth, that is, increases the binding points of the dyes, making the dyeing rate as high as 94.21%, which effectively improves the dyeing performance of the superfine fiber synthetic leather, and is beneficial to the superfine fiber synthetic leather. Industrial development.

The content of the present invention is not limited to the examples listed, and any equivalent transformation of the technical solution of the present invention adopted by those of ordinary skill in the art by reading the description of the present invention is covered by the claims of the present invention.

Claims (9)

1. a method of improving superfine fiber synthetic leather base cloth dyeability, is characterized in that: comprise the following steps:

1) preparation of collagen:

In gelatin, add water, it is 20%～40% gelatin solution that stirring makes to obtain after gelatin swelling mass concentration, regulating the pH value of gelatin solution is 8.0～10.0, then at 40～60 ℃, in gelatin solution, adds alkali protease to stir hydrolysis 2～6h, obtains collagen; Wherein, the addition of alkali protease accounts for 0.8%～2.0% of gelatin quality;

2) preliminary treatment of superfine fiber synthetic leather base cloth:

In rotary drum, add superfine fiber synthetic leather base cloth, in liquor ratio, be 3000%～6000%, temperature is, under the condition of 35～55 ℃, to adopt acid to process 2～5h to superfine fiber synthetic leather base cloth, obtains the superfine fiber synthetic leather base cloth of surface modification; Wherein, the consumption of acid is 10%～20% of superfine fiber synthetic leather base cloth quality;

3) modification of collagen to superfine fiber synthetic leather base cloth:

In liquor ratio, be 2000%～5000%, pH value is 2.0～9.0, temperature is under the condition of 20～60 ℃, to step 2) rotary drum in add collagen, by collagen graft modification to the superfine fiber synthetic leather base cloth of surface modification, reaction 0.5～4h, obtains collagen-modified superfine fiber synthetic leather base cloth; The consumption of collagen be surface modification superfine fiber synthetic leather base cloth quality 4%～20%;

4) dyeing of collagen-modified superfine fiber synthetic leather base cloth:

In liquor ratio, be 2000%～5000%, pH value is 4.5～5.5, temperature is, under the condition of 50～60 ℃, in the rotary drum of step 3), to add dyestuff to collagen-modified superfine fiber synthetic leather base cloth dyeing 1～4h, obtains the superfine fiber synthetic leather base cloth of dyeing; Wherein the consumption of dyestuff is 1%～8% of collagen-modified superfine fiber synthetic leather base cloth quality.

2. a kind of method of improving superfine fiber synthetic leather base cloth dyeability according to claim 1, is characterized in that: in described step 1), gelatin extracts from discarded leather bits.

3. a kind of method of improving superfine fiber synthetic leather base cloth dyeability according to claim 1, is characterized in that: the pH value in described step 1) adopts sodium hydroxide solution to regulate.

4. a kind of method of improving superfine fiber synthetic leather base cloth dyeability according to claim 1, is characterized in that: the acid described step 2) is the concentrated sulfuric acid or the analytically pure formic acid of mass fraction 98%.

5. a kind of method of improving superfine fiber synthetic leather base cloth dyeability according to claim 1, is characterized in that: the pH value in described step 3) adopts sodium hydroxide solution or dilute sulfuric acid to regulate.

6. a kind of method of improving superfine fiber synthetic leather base cloth dyeability according to claim 1, it is characterized in that: in described step 3), before adding collagen in rotary drum, add crosslinking agent and react 0.5-4h, the superfine fiber synthetic leather base cloth quality 1%-18% that the addition of crosslinking agent is surface modification.

7. a kind of method of improving superfine fiber synthetic leather base cloth dyeability according to claim 6, is characterized in that: described crosslinking agent be tanning agent F ?90 or tanning agent TWT.

8. a kind of method of improving superfine fiber synthetic leather base cloth dyeability according to claim 1, is characterized in that: the pH value in described step 4) adopts dilute sulfuric acid to regulate.

9. a kind of method of improving superfine fiber synthetic leather base cloth dyeability according to claim 1, is characterized in that: the dyestuff in described step 4) is ACID DYES or REACTIVE DYES.