METHOD FOR SCOURING AND BLEACHING COTTON FABRIC WITH COMPOSITE ENZYME PREPARATION IN ONE BATH

Abstract

A method for scouring and bleaching cotton fabric with composite enzyme preparation in one bath is provided. The method relates to the application of composite alkaline enzyme preparation in scouring and bleaching processes of cotton fabric. The enzyme preparation for scouring and bleaching cotton fabric is compounded from cutinase, alkaline pectase, alkaline xylanase, alkaline cellulose, and carbohydrate oxidase. The method includes: scouring the cotton fabric by adding the composite enzyme preparation, glucose, oxidation bleaching stabilizer RB-3, penetrant JFC, and Triton X-100 in a treating bath at 55-70° C. and pH 8-10, and then bleaching the cotton fabric for 30 min by directly adding tetraacetyl ethylenediamine (TAED) in the scouring bath to activate hydrogen peroxide. After being treated by the method of the present invention, the cotton fabric has high impurity removal ratio, favorable wettability, and high whiteness. The present invention has the advantages of low power consumption, short process flow, and being environment friendly, and may be used to replace conventional chemical treatment process under the condition of concentrated alkali and high temperature.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for scouring and bleaching cotton fabric with composite enzyme preparation in one bath, and belongs to the field of the application of alkaline enzyme preparations in scouring and bleaching process of cotton fabric.

2. Related Art

The conventional process for scouring and bleaching cotton fabric generally has the disadvantages of high temperature, high alkali, high pollution, and being not environmental friendly. The use of enzyme in scouring and bleaching cotton fabric in one bath has the advantages of mild processing conditions, low fabric damage, low power consumption, being environment friendly, and short process flow. The use of enzyme in scouring and bleaching cotton fabric in one bath, by adopting a preferable composite enzyme preparation and optimizing the process conditions, is a topic of practical significance that keeps close contact with actual production and is productivity-oriented.

SUMMARY OF THE INVENTION

The present invention is directed to a method for scouring and bleaching cotton fabric with a composite enzyme preparation, in order to solve the problems of high power consumption and high pollution in the current chemical pre-treatment method of cotton fabric, without severe damage on the fabric, while shortening the process flow.

The technical solution of the present invention includes the following steps.

1) Cotton fabric is scoured with a composite enzyme preparation. The scouring enzyme preparation is compounded from cutinase, alkaline pectase, alkaline xylanase, alkaline cellulose, and carbohydrate oxidase. The scouring bath composition includes: the composite enzyme preparation 0.5-1.5 g/L, penetrant WC (Jiangsu Hai'an Petrochemical Plant) 1-5 g/L, glucose 1.5-3 g/L, oxidation bleaching stabilizer RB-3 (Jiangsu Yixing Jiayu Chemical Plant) 3 g/L, and Triton X-100 0.5-1 g/L. The process conditions are: the mass ratio of the cotton fabric and the scouring bath 1:20, pH 8-10, temperature 55-70° C., and processing time 60 min. The mass percentages of the composite enzyme preparation are cutinase 10%-20%, alkaline pectase 20%-30%, alkaline xylanase 20%-30%, alkaline cellulose 5%-10%, and carbohydrate oxidase 15%-25%. Enzymatic scouring of cotton fabric under alkaline condition facilitates the removal of impurities in the cotton fiber and the performance of bleaching process. Alkaline pectase and cutinase can cooperate to effectively remove hydrophobic impurities (for example, wax and pectin) on the surface of the cotton fiber, thereby improving the wettability of the fabric. Alkaline xylanase and alkaline cellulose can effectively degrade the cotton seed hull on the cotton fabric, and alkaline xylanase can promote the improvement of the whiteness of fabric and thus reduce the amount of H₂O₂ required by the bleaching process. H₂O₂ is generated by carbohydrate oxidase in the scouring bath with glucose as substrate. Under this scouring condition, H₂O₂ has weak degradation effect on the impurities on the surface of the fiber, and can improve the accessibility of alkaline pectase, cutinase, alkaline xylanase on their respective substrates, thereby accelerating the catalytic effect of the enzymes. The treatment effect of the present invention can meet the processing requirements of subsequent process, thus avoiding concentrated alkali and high temperature in the chemical treatment method, with low power consumption and being environment friendly.

2) The cotton fabric after scouring is bleached in the same bath. After scouring, tetraacetyl ethylenediamine (TAED, Henan Hongye Chemical Co., Ltd.) 0.5-2 g/L is directly added into the scouring bath. The processing conditions are: pH 10, temperature 55-70° C., and processing time 30 min. H₂O₂ is generated by carbohydrate oxidase with glucose as substrate to bleach the cotton fabric, thus no additional H₂O₂ is needed. The whiteness of the treated fabric can meet the requirements of the subsequent process. Tetraacetyl ethylenediamine (TAED), as an activator of H₂O₂, can effectively activate H₂O₂ at a low temperature, to enhance the oxidation capacity of H₂O₂, thereby improving the whiteness of the fabric and shortening the bleaching time.

The beneficial effect of the present invention is that cotton fabric is scoured and bleached with a composite enzyme preparation in one bath. The scouring enzyme preparation is compounded from cutinase, alkaline pectase, alkaline xylanase, alkaline cellulose, and carbohydrate oxidase. When scouring and bleaching cotton fabric with the composite enzyme preparation in one bath, the processing conditions are mild, no damage on the fabric is caused, and at the same time, the power consumption is low and the process is environment friendly, and the fabric can meet the processing requirements of subsequent process. When scouring the cotton fabric with the composite enzyme under alkaline condition, alkaline pectase and cutinase can cooperate to effectively remove the pectin and wax on the surface of the fiber, thereby improving the wettability of the fabric. Alkaline cellulose and alkaline xylanase can degrade the cotton seed hull on the cotton fabric. Meanwhile, alkaline xylanase has bleaching effect on the fabric and thus can decrease the working load of H₂O₂ bleaching. H₂O₂ for bleaching is generated by carbohydrate oxidase in the scouring bath with glucose as substrate. Under the scouring condition, the oxidation effect of H₂O₂ can further promote the effect of alkaline pectase, alkaline cellulose, and alkaline xylanase on the substrates, thereby significantly improving the removal effect of the enzymes on the impurities in the fabric. Therefore, by compounding the several enzymes to scour and bleaching cotton fabric in one bath, the wettability, removal ratio of impurities, and whiteness of the obtained fabric are equivalent to that of the fabric treated by the conventional chemical method, but no damage on the fabric is caused, and the process is environment friendly. H₂O₂ can be generated by carbohydrate oxidase with glucose or other oligosaccharide as substrate for bleaching the fabric, thus no additional H₂O₂ is required to be added in the bleaching bath, and the whiteness of the cotton fabric can meet the processing requirement of the subsequent process. Due to the advantages of low power consumption and being environment friendly, the process of enzymatic scouring and bleaching cotton fabric in one bath is an ideal method to replace the conventional chemical treatment method.

Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

No drawings

DETAILED DESCRIPTION OF THE INVENTION

Embodiment 1

Conventional Scouring and Bleaching Process (Comparative Example)

Fabric: Cotton poplin (15 tex×15 tex, 524 threads/10 cm×283 threads/10 cm)

Conventional scouring process: alkaline scouring: NaOH 15 g/L, penetrant JFC 5 g/L, NaHSO₃ 1 g/L, NaPO₃ 1 g/L, pH 13, temperature 95° C., bath ratio 1:20, processing time 60 min.

Conventional bleaching process: 30% H₂O₂ 5 g/L, oxidation bleaching stabilizer RB-3 1 g/L, pH 10.5, bath ratio 1:20, temperature 90° C., processing time 60 min. The results are as shown in Table 1.

Embodiment 2

Enzymatic Scouring and Conventional Bleaching Process (Comparative Example)

Fabric: Cotton poplin (15 tex×15 tex, 524 threads/10 cm×283 threads/10 cm)

Enzymatic scouring: scouring enzyme preparation (cutinase, alkaline pectase, alkaline xylanase, alkaline cellulase) 1.5 g/L; penetrant JFC 5 g/L, and Triton X-100 1 g/L; bath ratio 1:20, pH 10, temperature 60° C., processing time 60 min.

Conventional bleaching: 30% H₂O₂ 5 g/L, oxidation bleaching stabilizer RB-3 3 g/L, pH 11, bath ratio 1:20, temperature 90° C., processing time 60 min.

The enzymatic scouring of cotton fabric has equivalent treatment effect to that of the alkaline scouring, but has relatively low damage on the fabric. The results are as shown in Table 1.

Embodiment 3

Enzymatic Scouring of Cotton Fabric and Bleaching with H₂O₂ Generated by Glucose Oxidase (Not in the Same Bath)

Fabric: Cotton poplin (15 tex×15 tex, 524 threads/10 cm/283 threads/10 cm)

Enzymatic scouring: scouring enzyme preparation (cutinase, alkaline pectase, alkaline xylanase, alkaline cellulase) 1.5 g/L; penetrant JFC 5 g/L, and Triton X-100 1 g/L; bath ratio 1:20, pH 10, temperature 60° C., processing time 60 min.

Bleaching process with H₂O₂ generated by carbohydrate oxidase added in the bleaching bath: the bleaching bath composition includes: carbohydrate oxidase 1.0 g/L, glucose 3 g/L, penetrant JFC 4 g/L, oxidation bleaching stabilizer RB-3 3 g/L, bath ratio 1:20, pH 8, temperature 55° C., processing time 60 min, followed by raising the temperature to 90° C. and adjusting to pH 10 for bleaching for 60 min.

H₂O₂ is generated by carbohydrate oxidase with glucose as substrate. The results are as shown in Table 1.

Embodiment 4

Enzymatic Scouring and Bleaching of Cotton Knitted Fabric in One Bath

Fabric: Cotton knitted fabric (14.5 tex)

Enzymatic scouring: scouring enzyme preparation (cutinase, alkaline pectase, alkaline xylanase, alkaline cellulose, and carbohydrate oxidase) 0.5 g/L; penetrant JFC 1 g/L, oxidation bleaching stabilizer RB-3 3 g/L, and Triton X-100 0.5 g/L; bath ratio 1:20, pH 10, temperature 60° C., processing time 60 min. After scouring, 0.5 g/L tetraacetyl ethylenediamine is directly added into the scouring bath for 30-min treatment. The enzymatic scouring of cotton fabric in one bath has equivalent treatment effect to that of conventional alkaline process, but has relatively short process flow and low power consumption. The results are as shown in Table 1.

Embodiment 5

Enzymatic Scouring and Bleaching of Cotton Fabric in One Bath

Fabric: Cotton poplin (15 tex×15 tex, 524 threads/10 cm×283 threads/10 cm)

Process: scouring enzyme preparation (cutinase, alkaline pectase, alkaline xylanase, alkaline cellulose, and carbohydrate oxidase) 1.5 g/L; penetrant JFC 5 g/L, oxidation bleaching stabilizer RB-3 3 g/L, and Triton X-100 1 g/L; bath ratio 1:20, pH 10, temperature 60° C., processing time 60 min. After scouring, 2 g/L tetraacetyl ethylenediamine is directly added into the scouring bath for 30-min treatment. The enzymatic scouring of cotton fabric in one bath has equivalent treatment effect to that of conventional alkaline process, but has relatively short process flow and low power consumption. The results are as shown in Table 1.

Embodiment 6

Enzymatic Scouring and Bleaching of Cotton Fabric in One Bath

Fabric: Cotton poplin (15 tex×15 tex, 524 threads/10 cm×283 threads/10 cm)

Process: The conditions are the same as those in Embodiment 5, except that alkaline pectase is not included in the scouring enzyme preparation, and the scouring temperature is 70° C. It is indicated that alkaline pectase can effectively remove the pectin on the surface of cotton fiber, and thus facilitate the improvement of the wettability of the fabric. The results are as shown in Table 1.

Embodiment 7

Enzymatic Scouring and Bleaching of Cotton Fabric in One Bath

Fabric: Cotton poplin (15 tex×15 tex, 524 threads/10 cm×283 threads/10 cm)

Process: The conditions are the same as those in Embodiment 5, except that cutinase is not included in the scouring enzyme preparation.

It is indicated that cutinase can effectively remove the wax on the surface of the cotton fiber, and thus facilitate the improvement of the wettability of the fabric. The results are as shown in Table 1.

Embodiment 8

Enzymatic Scouring and Bleaching of Cotton Fabric in One Bath

Fabric: Cotton poplin (15 tex×15 tex, 524 threads/10 cm×253 threads/10 cm)

Process: The conditions are the same as those in Embodiment 5, except that alkaline xylanase is not included in the scouring enzyme preparation.

It is indicated that alkaline xylanase can promote the improvement of the whiteness of the cotton fabric. The results are as shown in Table 1.

Embodiment 9

Fabric: Cotton poplin (15 tex×15 tex, 524 threads/10 cm×283 threads/10 cm)

Process: The conditions are the same as those in Embodiment 5, except that alkaline cellulase is not included in the scouring enzyme preparation.

It is indicated that alkaline cellulose can improve the wettability of the fabric, and has a certain degradation effect on cotton seed hull, but has some damage on the strength of the cotton fabric. The results are as shown in Table 1.

Embodiment 10

Fabric: Cotton poplin (15 tex×15 tex, 524 threads/10 cm×283 threads/10 cm)

Process: The conditions are the same as those in Embodiment 5, except that after scouring, tetraacetyl ethylenediamine is not added in the bleaching bath.

It is indicated that tetraacetyl ethylenediamine has an activation effect on H₂O₂, and H₂O₂ bleaching has significant influence on the whiteness of the cotton fabric and the removal of cotton seed hull. The results are as shown in Table 1.

TABLE 1
Treatment results of the embodiments
				Cotton
		Capillary	Pectin	seed hull	Bursting
	Whiteness	effect	removal	removal	strength
	(wh)	(cm)	rate (%)	rate (%)	(N)
Embodiment 1	86.03	14.36	95.21	89	445
(comparative)
Embodiment 2	85.53	13.76	94.63	85	482
(comparative)
Embodiment 3	83.87	13.23	92.91	86	479
(comparative)
Embodiment 4	88.87	15.23	96.48	100	489
Embodiment 5	85.13	13.76	92.78	84	476
Embodiment 6	84.67	11.46	72.35	83	475
(comparative)
Embodiment 7	84.09	11.06	84.35	83	480
(comparative)
Embodiment 8	78.09	13.38	92.07	80	478
(comparative)
Embodiment 9	85.2	12.22	92.31	79	468
(comparative)
Example 10	75.06	13.52	84.03	76	481
(comparative)

Claims

1. A method for scouring and bleaching cotton fabric with a composite enzyme preparation in one bath, comprising:

1) scouring the cotton fabric with a composite enzyme preparation, wherein the scouring enzyme preparation is compounded with cutinase, alkaline pectase, alkaline xylanase, alkaline cellulose, and carbohydrate oxidase, the scouring bath composition comprises: the composite enzyme preparation 0.5-1.5 g/L, penetrant NC 1-5 g/L, glucose 1.5-3 g/L, oxidation bleaching stabilizer R8-3 3 g/L, and Triton X-100 0.5-1 g/L, the processing conditions are: the mass ratio of the cotton fabric and the scouring bath 1:20, pH 8-10, temperature 55-70° C., and processing time 60 min, and the mass percentages of the composite enzyme preparation are cutinase 10%-20%, alkaline pectase 20%-30%, alkaline xylanase 20%-30%, alkaline cellulose 5%-10%, and carbohydrate oxidase 15%-25%;

2) after scouring, bleaching the cotton fabric in the same bath, wherein tetraacetyl ethylenediamine 0.5-2 g/L is directly added into the scouring bath after scouring, and the bleaching conditions are: pH 10, temperature 55-70° C., and processing time 30 min.