阅读说明：本技术 一种低温练漂剂及其制备方法和应用 (Low-temperature scouring and bleaching agent and preparation method and application thereof ) 是由 汪南方 张应思 张帆 阳海 易兵 于 2020-10-22 设计创作，主要内容包括：本申请公开了一种低温练漂剂及其制备方法和应用,该低温练漂剂的质量百分比组成为主催化剂铜配合物0.5%-5%、副催化剂有机活化剂1%-10%、耐碱渗透精练剂8%-15%、螯合分散剂4%-8%、10%有机硅消泡剂0.05%-0.1%、余量为水,所得低温练漂剂与烧碱、双氧水配合后用于棉织物前处理中,工作液浸渍或浸轧工作液,然后水洗、脱水、烘干完成前处理。本发明利用了铜配合物和有机活化剂协同催化双氧水低温释放漂白活性物种的机理实现棉织物低温精练漂白,不仅能保持常规的白度和毛效,而且织物损伤小、毛感蓬松柔软、节能环保,工艺简单,易实现工业化。(The application discloses a low-temperature scouring and bleaching agent and a preparation method and application thereof, the low-temperature scouring and bleaching agent comprises, by mass, 0.5% -5% of a main catalyst copper complex, 1% -10% of an auxiliary catalyst organic activator, 8% -15% of an alkali-resistant penetrating scouring agent, 4% -8% of a chelating dispersant, 0.05% -0.1% of a 10% organic silicon defoaming agent and the balance of water, the obtained low-temperature scouring and bleaching agent is used in pretreatment of cotton fabrics after being matched with caustic soda and hydrogen peroxide, a working solution is soaked or padded in the working solution, and then the pretreatment is completed by washing, dewatering and drying. The invention realizes the low-temperature scouring and bleaching of cotton fabrics by utilizing the mechanism that the copper complex and the organic activator synergistically catalyze hydrogen peroxide to release bleaching active species at low temperature, not only can maintain the conventional whiteness and capillary effect, but also has the advantages of small fabric damage, fluffy and soft fluffy feel, energy conservation, environmental protection, simple process and easy realization of industrialization.)

1. The low-temperature scouring and bleaching agent is characterized by comprising the following components in percentage by mass: 0.5 to 5 percent of copper complex, 1 to 10 percent of organic activator as a side catalyst, 8 to 15 percent of alkali-resistant penetrating scouring agent, 4 to 8 percent of chelating dispersant, 0.05 to 0.1 percent of 10 percent of organic silicon defoamer and the balance of water, wherein the total content of the components is 100 percent.

2. The scouring and bleaching agent as claimed in claim 1, wherein the chemical structural general formula of the copper complex is [ CuL ] Y, wherein Cu represents copper ions of central ions of the complex, L represents ligands of internal boundaries of the complex, Y represents external counter ions, L is structurally characterized by ligands containing more than four coordination atoms in a molecule, and Y is structurally characterized by one or two of tungstate ions, molybdate ions and silicate ions.

3. The scouring and bleaching agent according to claim 2, wherein L is a ligand characterized by the structural feature of N or O, and comprises one or two of N-hydroxyethyl-diethylenetriamine, N-salicylaldehyde diethylenetriamine, triethylene tetramine, tetraethylenepentamine, polyethyleneimine, polyacrylamide and polyamide-amine.

4. The scouring and bleaching agent as claimed in claim 1, wherein the organic activating agent of the secondary catalyst is one or more of urea, cyanoacetylurea, dicyandiamide and cyanamide.

5. The scouring agent of claim 1, wherein the alkali-resistant penetrating scouring agent is a compound of two or more of AEO-9, 1306, 1309, XP70, XP90, sodium isooctyl alcohol sulfonate and sodium isooctyl alcohol polyoxyethylene ether sulfate.

6. The scouring and bleaching agent according to claim 1, wherein the chelating and dispersing agent is a compound of two or more of nitrilotriacetic acid iminodiacetic acid, sodium citrate, sodium tartrate, low molecular weight sodium polyacrylate, sodium polymaleate, low molecular weight maleic acid-acrylic acid copolymer, and polyaspartic acid.

7. The scouring and bleaching agent according to claim 1, wherein the silicone defoamer is a compound of two or more of polyether, silicone and polyether-modified silicon.

8. The method for preparing the low-temperature scouring and bleaching agent as claimed in any one of claims 1 to 7, is characterized by comprising the following steps:

1) preparing raw materials; the components are prepared according to the mass percentage as follows: 0.5 to 5 percent of copper complex, 1 to 10 percent of organic activator as a side catalyst, 8 to 15 percent of alkali-resistant penetrating scouring agent, 4 to 8 percent of chelating dispersant, 0.05 to 0.1 percent of 10 percent of organic silicon defoamer and the balance of water, wherein the total content of the components is 100 percent;

2) adding the alkali-resistant penetrating scouring agent obtained in the step 1), a chelating dispersant, an organic activator and water accounting for one half of the total amount into a reaction kettle, heating to 50-70 ℃, stirring at the stirring speed of 200-800rpm until the system is completely transparent, dripping one fourth of the water-soluble copper complex solution into the reaction kettle, continuously stirring for 1-2 hours after dripping, cooling to room temperature, adding an organic silicon defoaming agent and the remaining one fourth of the water, and continuously stirring for 30-60 minutes to obtain the final low-temperature scouring and bleaching agent.

9. Use of the low temperature scouring and bleaching agent of any one of claims 1 to 7 in the pretreatment of cotton fabrics.

10. Use according to claim 9, characterized in that it comprises the following steps:

1) preparing scouring and bleaching working solution: the formula of the working solution is 1 g/L-6 g/L of low-temperature scouring and bleaching agent, 1 g/L-10 g/L of caustic soda and 6 g/L-30 g/L of 30% hydrogen peroxide;

2) pre-treatment of scouring and bleaching: soaking cotton fabrics into scouring and bleaching working solution, wherein the bath ratio is 1: 5-15, treating for 45-75 minutes at the temperature of 60-80 ℃, or padding a working solution with the rolling residual rate of 90-120 percent, and piling for 45-75 minutes at the temperature of 60-80 ℃;

3) and (3) post-treatment: the fabric is subjected to conventional washing, dehydration and drying to obtain a cotton fabric pretreatment semi-product; the cotton fabric comprises pure cotton knitted fabric, cotton stretcher knitted fabric, pure cotton woven fabric or pure cotton elastic woven fabric.

Technical Field

The invention relates to a low-temperature scouring and bleaching agent, a preparation method and application thereof, and belongs to the technical field of textile printing and dyeing.

Background

The pure cotton fabric has the natural characteristics of moisture absorption, ventilation, heat preservation and the like, and is popular with a plurality of consumers. But the accompanying impurities and the weaving slurry of the cotton fiber affect the appearance, water absorption, ventilation, hand feeling, fluffiness and the like of the fabric. Therefore, the pure cotton fabric needs to be processed before dyeing and printing. The traditional scouring and bleaching process is an alkaline-oxygen pretreatment process, impurities such as cotton companion and the like and weaving slurry are removed by using sodium hydroxide, hydrogen peroxide and related auxiliaries under a high-temperature condition, and the capillary effect and whiteness of fibers are improved so as to meet the requirements of dyeing, printing and taking. The traditional scouring and bleaching process needs high temperature to promote hydrogen peroxide to generate bleaching active species, the heat preservation treatment at the temperature of 98-100 ℃ is carried out for 40-60 min, a large amount of steam is consumed, and the strong damage and loss of fibers are aggravated under the condition of high temperature and alkali oxygen. The global consensus is that water and sewage are saved, energy consumption is saved, and therefore, the low-temperature scouring and bleaching technology becomes a hotspot and a key point for research and development in the industry.

At present, the common practice of low-temperature alkaline-oxygen bleaching technology is to introduce an activator or catalyst into the existing alkaline-oxygen bleaching system. The activator or catalyst can effectively reduce the decomposition activation energy of the hydrogen peroxide so that the hydrogen peroxide can generate bleaching active species under the condition of lower temperature. They are classified into two main categories of organic activators and metal enzyme-like catalysts from the action mechanism. The organic activator mainly includes amides (tetraacetylethylenediamine (TAED), sodium Nonanoyloxybenzenesulfonate (NOBS), N- (4- (triethylammoniumthylene) benzoyl) caprolactam chloride (TBCC), urea, diacetyldimethylurea), cyanamide (betaine acetyl nitrile chloride (TSJA), dicyandiamide, cyanoacetylurea, cyanamide) and guanidine (1-diacetylguanidine, 1-dimethylguanidine sulfate, 1-dimethylbiguanide hydrochloride), and the metal biomimetic catalyst mainly includes phthalocyanine complex, porphyrin complex, nitrogen-containing macrocyclic complex, Schiff base Saltren complex, Schiff base Salen complex, etc. Researches show that the activating agent and the catalyst have the advantages of reducing the bleaching temperature of hydrogen peroxide, reducing strength loss, fluffy and soft hand feeling of fabrics and the like when used for oxygen bleaching of cotton fabrics. The organic activator reacts with hydrogen peroxide to generate peroxy acid with stronger oxidability, so that bleaching is carried out at low temperature, but the organic activator has the defects of high dosage, easy hydrolysis and high cost. When the metal enzyme-like catalyst is used for low-temperature oxygen bleaching of cotton fabrics, the metal enzyme-like catalyst has the characteristics of low catalyst consumption and high efficiency, the cost performance is obviously superior to that of an organic activator, and complex metal enzyme-like catalyst complexes, such as phthalocyanine complexes, porphyrin complexes, nitrogen-containing macrocyclic complexes and the like, have the defects of long synthesis route, harsh reaction conditions, high preparation cost and poor catalytic selectivity, and limit the application of the metal enzyme-like catalyst complexes in actual production. The compounding and the efficiency enhancement of the organic activator and the metal enzyme-imitating catalyst are effective methods for solving the problem. Chinese invention CN106149347A proposes a low-temperature scouring and bleaching agent of a composite catalyst, heavy metal salt and organic activator (cyanamide and TAED) are introduced into the scouring agent to form a composite hydrogen peroxide catalyst, and the scouring and bleaching temperature of cotton fabrics can be reduced to 60-80 ℃. However, the heavy metal salt is directly added into the scouring agent, the metal salt is easy to hydrolyze to generate hydroxide or oxide, ineffective decomposition of hydrogen peroxide can be increased in scouring and bleaching, so that the whiteness is not high, and even the heavy metal salt is adsorbed on the cloth surface to generate holes.

Disclosure of Invention

The invention aims to reduce the scouring and bleaching temperature of cotton fabrics, save energy, reduce emission and reduce the influence of high-temperature scouring and bleaching on the quality of the cotton fabrics such as hand feeling, strength and the like. The invention adopts a copper complex with a special structure as a main catalyst and a low-price organic activator as a secondary catalyst to form a compound catalyst, and the compound catalyst is introduced into a scouring agent and chelating dispersant system to form a new low-temperature scouring and bleaching agent for low-temperature scouring and bleaching of cotton fabrics, so that the activator and the oxidant can generate bleached active species together at a lower temperature and mild alkalinity, the low-temperature high-efficiency scouring and bleaching is realized to save energy, two process steps of neutralization and deoxidization are omitted, and the water consumption and the discharge amount are reduced; the scouring and bleaching temperature is low, the utilization rate of hydrogen peroxide is high, the copper complex and the organic activator with special structures have strong alkali resistance and hydrolysis resistance, the catalytic activity is stable and durable, the problems of hard hand feeling, low fabric strength and the like of the fabric caused by high-temperature alkali oxygen are avoided, and the quality and the wearability of the cotton fabric are improved.

In order to solve the technical problem, the application discloses a low-temperature scouring and bleaching agent which comprises the following components in percentage by mass: 0.5 to 5 percent of copper complex, 1 to 10 percent of organic activator as a side catalyst, 8 to 15 percent of alkali-resistant penetrating scouring agent, 4 to 8 percent of chelating dispersant, 0.05 to 0.1 percent of 10 percent of organic silicon defoamer and the balance of water, wherein the total content of the components is 100 percent.

Furthermore, the chemical structural general formula of the copper complex is [ CuL ] Y, wherein Cu represents bivalent copper ions of complex central ions, L represents complex internal ligands, Y represents external counter ions, the structural characteristics of L are ligands containing more than four coordination atoms in molecules, and the structural characteristics of Y are one or two of tungstate ions, molybdate ions and silicate ions.

Further, L is structurally characterized by a ligand of N or O, and comprises one or two of N-hydroxyethyl-diethylenetriamine, N-salicylaldehyde diethylenetriamine, triethylene tetramine, tetraethylene pentamine, polyethyleneimine, polyacrylamide and polyamide-amine.

Further, the organic activating agent of the secondary catalyst is one or more than two of cyanoacetylurea, dicyandiamide and cyanamide.

Further, the alkali-resistant osmotic scouring agent is a compound consisting of more than two of AEO-9, 1306, 1309, XP70, XP90, isooctanol sodium sulfonate and isooctanol polyoxyethylene ether sodium sulfate.

Further, the AEO-9 is a condensate of C10-C12 fatty alcohol and ethylene oxide; 1309 is a condensate of C13 isomeric alcohol and ethylene oxide; the XP90 is a condensate of C10 isomeric alcohol and ethylene oxide.

The chelating dispersant is a compound of more than two of nitrilotriacetic acid (NTA), iminodiacetic acid, sodium citrate, sodium tartrate, low molecular weight sodium polyacrylate, sodium polymaleate, low molecular weight maleic acid-acrylic acid copolymer and polyaspartic acid.

Furthermore, the organic silicon defoaming agent is a compound formed by more than two of polyether, organic silicon and polyether modified silicon.

The application also discloses a preparation method of the low-temperature scouring and bleaching agent, which comprises the following steps:

1) preparing raw materials; the components are prepared according to the mass percentage as follows: 0.5 to 5 percent of copper complex, 1 to 10 percent of organic activator as a side catalyst, 8 to 15 percent of alkali-resistant penetrating scouring agent, 4 to 8 percent of chelating dispersant, 0.05 to 0.1 percent of 10 percent of organic silicon defoamer and the balance of water, wherein the total content of the components is 100 percent;

2) adding the alkali-resistant osmotic scouring agent, the chelating dispersant, the organic activator and water accounting for one half of the total amount into a reaction kettle, heating to 50-70 ℃, stirring (the speed is required to be slow), the stirring speed is 200 plus materials at 800rpm until the system is completely transparent, then dropping a water-soluble copper complex solution accounting for one fourth of the total amount (dropping slowly is preferred), continuously stirring for 1-2 hours after dropping is finished, cooling to room temperature, then adding the organic silicon defoaming agent and the remaining one fourth of water (adding slowly is preferred), and continuously stirring for 30-60 minutes to obtain the final low-temperature scouring and bleaching agent.

The application also discloses an application of the low-temperature scouring and bleaching agent in scouring and bleaching cotton fabrics.

Further, the cotton fabric includes pure cotton knitted fabric, cotton stenter knitted fabric, pure cotton woven fabric, and pure cotton stretch woven fabric.

Further, the application of the low-temperature scouring and bleaching agent in scouring and bleaching cotton fabrics comprises the following steps:

1) preparing scouring and bleaching working solution: the formula of the working solution is 1 g/L-6 g/L of low-temperature scouring and bleaching agent, 1 g/L-10 g/L of caustic soda and 6 g/L-30 g/L of 30% hydrogen peroxide;

2) pre-treatment of scouring and bleaching: soaking cotton fabrics into scouring and bleaching working solution, wherein the bath ratio is 1: 5-15, treating for 45-75 minutes at the temperature of 60-80 ℃, or padding a working solution with the rolling residual rate of 90-120 percent, and piling for 45-75 minutes at the temperature of 60-80 ℃;

3) and (3) post-treatment: the fabric is subjected to conventional washing, dehydration and drying to obtain a cotton fabric pretreatment semi-product. The invention has the beneficial effects that:

compared with the prior art, the application can obtain the following technical effects:

(1) the invention adopts a low-temperature scouring and bleaching agent, wherein a copper complex with a special structure is used as a main catalyst, an organic activator is used as a secondary catalyst to form a composite catalyst, and the composite catalyst is introduced into a scouring agent and chelating dispersant system to form a novel low-temperature scouring and bleaching agent. The inner boundary of the copper complex with the special structure is complex cation with high stability constant formed by ligand containing more than four coordination atoms (N or O) and copper divalent ion; tungsten, molybdenum or silicon oxyacid radical anions are adopted outside the complex, a cage structure can be formed, internal cations are loaded inside the complex, the stability of the complex is further improved, and moreover, the special oxyacid radical anions can better stabilize active species released by catalyzing hydrogen peroxide by the complex cations, so that the ineffective decomposition of the hydrogen peroxide is greatly reduced, and the bleaching capacity of the oxygen bleaching working solution is improved.

(2) The organic activator contained in the low-temperature scouring and bleaching agent belongs to an cyanamide structure, has the advantages of wide source, low price, high alkali resistance, hydrolysis resistance, stability, high catalytic selectivity and the like, and has high dosage when being used alone, but the organic activator is compounded with a copper complex with a special structure, so that the organic activator can make up for the shortages, synergize and improve the low-temperature scouring and bleaching performance of the scouring and bleaching agent. The catalyst system selected by the invention has good compatibility with other components, the storage property of the auxiliary agent is stable, the using effect is durable, the material melting operation is simple, the production efficiency is improved, and the product quality is stabilized.

(3) The scouring penetrant, the chelating dispersant and the defoaming agent in the low-temperature scouring and bleaching agent do not contain APEO and phosphorus chemical substances, so that the ecological property of bleached fabrics and the non-toxicity and the harmlessness of wastewater discharge are ensured.

(4) The low-temperature scouring and bleaching temperature is between 60 and 80 ℃, which is lower than the conventional high-temperature scouring and bleaching temperature (about 100 ℃) in the prior art, and the problems of large energy consumption, hard hand feeling, low strength and the like of the conventional process are solved; when scouring and bleaching at low temperature, the swelling degree of the cotton fiber is obviously reduced, and the adsorption capacity of the fiber to alkali and bleaching agent is reduced, so that two procedures of neutralization and deoxidization are omitted, and the water consumption and discharge are reduced.

In a word, the technical scheme provided by the invention has the advantages of saving energy, reducing emission, and improving the quality and the service performance of the cotton fabric.

Detailed Description

The present invention is further illustrated by the following examples.

Example 1

(1) The fabric types are as follows: cotton knitted fabric (130 g/m)²）

(2) The process flow is as follows:

preparing a low-temperature scouring and bleaching agent: adding AEO 93 Kg, isooctyl alcohol sodium sulfonate 5 Kg, nitrilotriacetic acid 2Kg, sodium polyacrylate (molecular weight 6000) 2Kg, cyanoacetyl urea 1 Kg, and water 43 Kg into a reaction kettle, slowly heating to 50 ℃ and stirring at the stirring speed of 200 rpm until the system is completely transparent, slowly dropping 21.5 Kg of a solution of water dissolved with 0.5 Kg of N-hydroxyethyl-copper diethylenetriamine tungstate, continuously stirring for 1 hour after dropping, cooling to room temperature, slowly adding 0.05 Kg of a 10% solution of an organosilicon antifoaming agent and 21.95 Kg of water, and continuously stirring for 30 minutes to obtain the final low-temperature scouring bleaching agent;

preparing scouring and bleaching working solution: the formula of the working solution is 2g/L of the low-temperature scouring and bleaching agent, 2g/L of caustic soda and 8 g/L of 30 percent hydrogen peroxide;

pre-treatment of scouring and bleaching: soaking cotton fabrics into scouring and bleaching working solution, wherein the bath ratio is 1: 5, treating at the temperature of 60 ℃ for 75 minutes;

and (3) post-treatment: the fabric is washed, dehydrated and dried by conventional methods.

Example 2

(1) The fabric types are as follows: cotton-frame knitted fabric (180 g/m)²）

(2) The process flow is as follows:

preparing a low-temperature scouring and bleaching agent: adding 13062 Kg, XP 905 Kg, isooctanol polyoxyethylene ether sodium sulfate 8 Kg, iminodiacetic acid 3Kg, maleic acid-acrylic acid copolymer with low molecular weight (molecular weight 4000) 5 Kg, cyanoacetylurea 6 Kg, dicyandiamide 4 Kg and water 30 Kg into a reaction kettle, slowly heating to 70 ℃ and stirring at the stirring speed of 500 rpm until the system is completely transparent, dissolving 4.5 Kg of triethylene tetramine copper molybdate and 0.5 Kg of N-salicylaldehyde diethylene triamine copper molybdate solution in 15 Kg of water, slowly dripping, continuously stirring for 2 hours after dripping, cooling the temperature to room temperature, slowly adding 0.1 Kg of 10% organosilicon defoamer solution and 16.9 Kg of water, and continuously stirring for 60 minutes to obtain the final low-temperature scouring bleaching agent;

preparing scouring and bleaching working solution: the formula of the working solution is 1 g/L of the low-temperature scouring and bleaching agent, 1 g/L of caustic soda and 6 g/L of 30 percent hydrogen peroxide;

pre-treatment of scouring and bleaching: soaking cotton fabrics into scouring and bleaching working solution, wherein the bath ratio is 1: 15, treatment at a temperature of 80 ℃ for 45 minutes;

and (3) post-treatment: the fabric is washed, dehydrated and dried by conventional methods.

Example 3

(1) The fabric types are as follows: 21^s108X 58 pure cotton yarn card fabric

(2) The process flow is as follows:

preparing a low-temperature scouring and bleaching agent: adding AEO 93 Kg, 13093 Kg, XP 705 Kg, sodium citrate 2Kg, sodium tartrate 2Kg, polyaspartic acid 2Kg, dicyandiamide 2Kg, cyanamide 4 Kg and water 37 Kg into a reaction kettle, slowly heating to 60 ℃ and stirring at the stirring speed of 500 rpm until the system is completely transparent, slowly dropping 18.5 Kg of a solution of water-soluble 2.5 Kg of polyethyleneimine copper silicate, continuously stirring for 1.5 hours after dropping, cooling to room temperature, slowly adding 0.07 Kg of a 10% silicone defoamer solution and 18.93 Kg of water, and continuously stirring for 45 minutes to obtain the final low-temperature scouring and bleaching agent;

preparing scouring and bleaching working solution: the formula of the working solution is 6 g/L of the low-temperature scouring and bleaching agent, 10 g/L of caustic soda and 30 g/L of 30 percent hydrogen peroxide;

pre-treatment of scouring and bleaching: padding the fabric with scouring and bleaching working solution with a rolling residue rate of 90 percent, and piling the fabric for 75 minutes at a temperature of 80 ℃;

and (3) post-treatment: the fabric is washed, dehydrated and dried by conventional methods.

Example 4

(1) The fabric types are as follows: 21^s×(21^s+70D) 108X 58 pure cotton stretch yarn card fabric

(2) The process flow is as follows:

preparing a low-temperature scouring and bleaching agent: 13063 Kg, 13093 Kg, 6 Kg of isooctyl alcohol sodium sulfonate, 2Kg of sodium tartrate, 2Kg of sodium polymaleate, 1.5 Kg of cyanoacetylurea, 1.5 Kg of cyanamide and 40 Kg of water are added into a reaction kettle, the temperature is slowly raised to 50 ℃ and the stirring is carried out at the stirring speed of 250 rpm until the system is completely transparent, 20 Kg of water is dissolved to obtain a solution of 0.5 Kg of polyamidoamine copper tungstate and 0.5 Kg of tetraethylenepentamine copper silicate, the solution is slowly dripped in, the stirring is continuously carried out for 1 hour after the dripping is finished, the temperature is reduced to room temperature, 0.06 Kg of 10 percent of organic silicon defoamer solution and 19.94 Kg of water are slowly added, and the final low-temperature scouring and bleaching agent is obtained after the stirring is continuously carried out for 30 minutes;

preparing scouring and bleaching working solution: the formula of the working solution is 3 g/L of the low-temperature scouring and bleaching agent, 6 g/L of caustic soda and 20 g/L of 30 percent hydrogen peroxide;

pre-treatment of scouring and bleaching: padding the fabric with scouring and bleaching working solution with a rolling residue rate of 120%, and piling for 45 minutes at a temperature of 80 ℃;

and (3) post-treatment: the fabric is washed, dehydrated and dried by conventional methods.

Example 5

(1) The fabric types are as follows: pure cotton knitted fabric (150 g/m)²）

(2) The process flow is as follows:

preparing a low-temperature scouring and bleaching agent: adding 706 Kg of XP, 7 Kg of isooctyl alcohol sodium sulfonate, 2Kg of sodium citrate, 2Kg of polymaleic acid sodium, 2Kg of sodium polyacrylate (molecular weight is 6000), 1 Kg of cyanoacetyl urea and 40 Kg of water into a reaction kettle, slowly heating to 55 ℃ and stirring at the stirring speed of 400 rpm until the system is completely transparent, slowly dissolving 20 Kg of water into a solution of 0.5 Kg of polyethyleneimine copper molybdate and 0.5 Kg of polyacrylamide copper tungstate, continuously stirring for 1.5 hours after dripping is finished, cooling to room temperature, slowly adding 0.5 Kg of 10% organic silicon defoamer solution and 18.94 Kg of water, and continuously stirring for 50 minutes to obtain the final low-temperature scouring and bleaching agent;

preparing scouring and bleaching working solution: the formula of the working solution is 1 g/L of the low-temperature scouring and bleaching agent, 2g/L of caustic soda and 6 g/L of 30 percent hydrogen peroxide;

pre-treatment of scouring and bleaching: soaking cotton fabrics into scouring and bleaching working solution, wherein the bath ratio is 1: 10, treating at 70 ℃ for 45 minutes;

and (3) post-treatment: the fabric is washed, dehydrated and dried by conventional methods.

Example 6

(1) The fabric types are as follows: 20^s60 x 60 pure cotton plain cloth

(2) The process flow is as follows:

preparing a low-temperature scouring and bleaching agent: adding 7 Kg of isooctyl alcohol sodium sulfonate, 5 Kg of isooctyl alcohol polyoxyethylene ether sodium sulfate, 2.5 Kg of nitrilotriacetic acid, 2.5 Kg of polyaspartic acid, 1 Kg of cyanamide, 1 Kg of dicyandiamide and 40 Kg of water into a reaction kettle, slowly heating to 60 ℃ and stirring at the stirring speed of 300 rpm until the system is completely transparent, slowly dripping 20 Kg of water into a solution of 0.5 Kg of N-hydroxyethyl-diethylenetriamine copper tungstate and 0.5 Kg of N-salicylaldehyde diethylenetriamine copper silicate, continuously stirring for 2 hours after dripping is finished, cooling the temperature to room temperature, slowly adding 0.05 Kg of 10% organosilicon antifoaming agent solution and 19.95 Kg of water, and continuously stirring for 60 minutes to obtain the final low-temperature bleaching agent;

preparing scouring and bleaching working solution: the formula of the working solution is 3 g/L of the low-temperature scouring and bleaching agent, 6 g/L of caustic soda and 15 g/L of 30 percent hydrogen peroxide;

pre-treatment of scouring and bleaching: padding the fabric with scouring and bleaching working solution with a rolling residue rate of 120%, and piling for 45 minutes at a temperature of 80 ℃;

and (3) post-treatment: the fabric is washed, dehydrated and dried by conventional methods.

Comparative example 1

The fabric types are as follows: pure cotton knitted fabric (150 g/m)²）

Scouring and bleaching the fabric: by adopting a traditional high-temperature alkali-oxygen scouring and bleaching process, 7 g/L of 30% hydrogen peroxide, 2g/L of caustic soda, 2g/L of scouring agent (XP 709%, 11% of isooctyl alcohol sodium sulfonate and the balance of water), 2g/L of hydrogen peroxide stabilizer sodium silicate, 2g/L of chelating dispersant (3% of sodium citrate, 3% of sodium polymaleate, 3% of sodium acrylate (molecular weight 6000) and the balance of water), and the bath ratio is 1: and 15, carrying out heat preservation treatment for 30 minutes at the temperature of 98 ℃, neutralizing the treated fabric, deoxidizing, washing with water, dehydrating and drying.

Comparative example 2

The fabric types are as follows: 20^s60 x 60 pure cotton plain cloth

Scouring and bleaching the fabric: by adopting a traditional high-temperature alkaline-oxygen rolling and steaming process, 30 g/L of 30% hydrogen peroxide, 15 g/L of caustic soda, 10 g/L of scouring agent (11% of isooctanol sodium sulfonate, 9% of isooctanol polyoxyethylene ether sodium sulfate and the balance of water), 5g/L of hydrogen peroxide stabilizer sodium silicate, 4 g/L of chelating dispersant (5% of nitrilotriacetic acid, 5% of polyaspartic acid and the balance of water), 110% of rolling rate, steaming and stacking at the temperature of 102 ℃ for 60 minutes, and neutralizing, deoxidizing, washing, dehydrating and drying the treated fabric.

The performance parameters of the examples and comparative examples are shown in table 1.

Table 1 fabric properties and process energy and water consumption for examples 1-6 and comparative examples

Note: hand is expressed in terms of stiffness, with a higher value indicating poorer hand.

As can be seen from Table 1, the whiteness of the cotton knitted fabrics obtained in examples 1, 2 and 5 reached the level of comparative example 1, the strength retention and the hand feeling of the fabrics were better than those of comparative example 1, and the energy and water consumptions of examples 1, 2 and 5 were about 40-50% of those of comparative example 1. Similarly, the whiteness of the woven fabrics of examples 3, 4 and 6 is equivalent to that of comparative example 2, the strength and the hand feeling are better than those of comparative example 2, and the energy consumption and the water consumption of examples 3, 4 and 6 are about 40 to 50% of those of comparative example 2. In the preparation method, the components and the proportion of the low-temperature scouring agent are very critical; the composition consisting of copper complex, organic activator, refining penetrant, chelating dispersant and silicon defoamer is used as a novel low-temperature refining agent. The adopted copper complex has a special molecular structure, and the inner boundary of the copper complex is complex cations with high stability constant formed by ligands containing more than four coordination atoms (N or O) and copper divalent ions; the outside is tungsten, molybdenum or silicon oxyacid radical anion, and the catalyst has the characteristics of high alkali resistance, hydrolysis resistance, high stability, strong and long catalytic activity, small dosage and poor selectivity. The selected organic activator belongs to an amino cyanide structure, and has the characteristics of high alkali resistance, hydrolysis resistance and stability, high selectivity and high single use amount. The two components are compounded to realize synergistic interaction, the dosage of the catalyst is reduced, two catalytic paths are opened at the same time, the low-temperature catalytic performance of the two components on hydrogen peroxide is improved, the whiteness of the fabric is improved, the strength loss is reduced, the hand feeling quality is improved, the low-temperature scouring and bleaching function is realized, and the purposes of energy conservation and emission reduction are achieved. The refining penetrant, the chelating dispersant and the silicon defoamer are necessary components for refining process, and are added into the system, so that the preparation of the working solution is facilitated, the operation is simple and convenient, the quality consistency of the pre-treated semi-finished product is ensured, and the production efficiency is improved.

The proportion range of the composition consisting of the copper complex, the organic activator, the scouring penetrant, the chelating dispersant and the silicon defoamer is obtained by taking the performance (whiteness, strength, capillary effect and hand feeling) of the conventional pretreatment semi-finished fabric as a reference through most experiments, repeated verification and optimization analysis. Wherein, the proportion among the copper complex, the organic activator and the scouring penetrant plays a role in determining the performance of the semi-finished product. When the proportion of the copper complex and the organic activator exceeds the range, the decomposition rate of hydrogen peroxide is too high, the whiteness is deteriorated, the strength is reduced, and the hand feeling is deteriorated. The refining penetrant exceeding the proportion range leads to more washing times and increases in the amount of wastewater and COD.

The temperature and the rotating speed in the preparation process are also very critical; the temperature is too low to be beneficial to dissolution and dispersion, the transparency of the finished product of the auxiliary agent is not good, and the low-temperature bleaching effect and the front-back consistency are influenced; too high a temperature may lead to phase separation and delamination and hydrolysis of the catalyst, which may affect the bleaching effect. The rotating speed is too low to be beneficial to dissolution and dispersion, the transparency of the auxiliary agent is influenced, and the bleaching effect is influenced; the high rotating speed causes the long chain of the nonionic surfactant to be cut off, the stability of the system is poor, and the bleaching effect is influenced.

As used in the specification and claims, certain terms are used to refer to particular components or methods. As one skilled in the art will appreciate, different regions may refer to a component by different names. The present specification and claims do not intend to distinguish between components that differ in name but not in name. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. The description which follows is a preferred embodiment of the present application, but is made for the purpose of illustrating the general principles of the application and not for the purpose of limiting the scope of the application. The protection scope of the present application shall be subject to the definitions of the appended claims.

It is also noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a good or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such good or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a commodity or system that includes the element.

While the foregoing description shows and describes several preferred embodiments of the invention, it is to be understood, as noted above, that the invention is not limited to the forms disclosed herein, but is not to be construed as excluding other embodiments and is capable of use in various other combinations, modifications, and environments and is capable of changes within the scope of the inventive concept as expressed herein, commensurate with the above teachings, or the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.