JP2004218180A - Method for continuous enzymic refining of cotton fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for continuous enzymic refining using an enzyme, taking energy saving and taking protection of the environment into consideration. <P>SOLUTION: The method for continuous enzymic refining of cotton fiber includes the following steps, a step calculating the rate of dilution of each component with the lapse of time in the refining solution for cotton fiber comprising protopectinase, α-amylase and a surfactant, a step calculating the volume and concentration of each supplementary liquid to be supplied to the refining liquid based on the calculated results, and a step keeping the concentration of each component of the refining liquid constant by adding each supplementary liquid following the calculated amount and concentration. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a continuous enzymatic scouring method for cotton fibers using a cotton fiber scouring solution containing protopectinase, α-amylase, and a surfactant.

  Processing of cotton fibers is roughly classified into pretreatment and posttreatment. The pretreatment step is to remove impurities inherent in the cotton fiber (for example, pectin, lipid, wax, etc. coating the cellulose fiber) and impurities (for example, spinning oil, glue, etc.) attached in the weaving process. This is a process for converting cotton fibers into cellulose fibers that are chemically pure and uniform or similar. This pre-processing step is performed to facilitate the post-processing steps (dying and finishing processing steps) and improve reproducibility. As the pretreatment, usually, a treatment at a high temperature using a strongly alkaline liquid called a chemical method is performed. This method has various problems such as high energy cost, poor working environment, and inability to easily treat strongly alkaline waste liquid.

  As a means for solving such a problem, a scouring method using an enzyme has been studied in consideration of energy saving and environmental protection. As an enzyme scouring method, a scouring method using protopectinase has been proposed (for example, see Patent Document 1). However, when cotton fibers are scoured using this method, the purpose of complete scouring cannot be achieved because the protopectinase enzyme releases only pectin. In order to solve this problem, Kino et al. Studied a scouring method combining α-amylase and protopectinase in a batch system (for example, see Non-Patent Document 1), and perform protopectinase treatment after treatment with amylase by Tabata et al. A putting scouring method is also being studied (for example, see Non-Patent Document 2). However, after any scouring, the degree of water absorption and dyeing of the cotton fiber was not always satisfactory. In order to solve these problems, in the washing step after the enzymatic scouring, raising the washing temperature and using a washing solution containing a surfactant and a chelating agent have been attempted, and as a result, the effect of improving water absorption has been attempted. (Non-Patent Document 3). However, raising the washing temperature is not a practice of energy saving, and the use of a washing solution containing a surfactant and a chelating agent increases the COD value of wastewater, which is not preferable from the viewpoint of environmental protection. In addition, this method cannot be applied to all cases because a new cleaning liquid adjustment tank or pipeline is required for operation. Furthermore, in the method of Non-Patent Document 2, the number of steps is increased, the processing time is increased, the productivity is reduced, and the amount of water and energy used is increased, as compared with the conventional method.

As for the continuous bio scouring method, the conventional method is basically a method in which the dough is immersed in an enzyme reaction solution kept at a constant temperature (usually 50 ° C. or higher). Stability is required. In addition, since the amount of the enzyme in the scouring tank decreases with time, it is necessary to replenish the enzyme. Takashishi et al. Developed a device dedicated to bio-scouring, and introduced an automatic measurement system for enzyme activity in a scouring tank to solve the problem of enzyme replenishment (Non-Patent Document 4). However, this method requires a large-capacity enzyme reaction tank, and if the temperature of the reaction tank is maintained at a temperature required for scouring (55 ° C. or higher), 50% or more of the scouring enzyme is inactivated, Since the scouring speed is reduced to 1/8 to 1/4 of the normal speed, there are problems such as poor efficiency. In addition, the method of Takagishi et al. Is practically difficult to implement because the existing equipment cannot be used.
Japanese Patent No. 2944306 (2-5 pages) Kino et al., Textile Processing, 2000, Vol. 52, No. 7, p. 307-400 Tabata et al., Processing Technology, 2000, Vol. 35, No. 9, p. 528-531 LENTING, H .; B. M. & ZWEIER, E. , Neth. Textile Research Journal, 2002, 72 (9), p. 825-831 Takagishi et al., AATCC Review, 2001, 1 (8), p. 32-34

  Therefore, an effective continuous enzymatic scouring method that replaces the chemical method has not yet been developed, and there is a need for the development of a continuous enzymatic scouring method using enzymes that easily consider energy and environmental protection with existing equipment. ing.

  The present inventors have conducted intensive studies to solve the above problems, and as a result, it was not necessary to introduce new equipment, and a scouring liquid for cotton fiber containing protopectinase, α-amylase, and a surfactant as components. The present inventors have found that the above problems can be solved by constructing a method for maintaining the concentration of each component without deactivating the enzyme therein, and completed the present invention.

  The present invention provides a step of calculating a time-dependent dilution rate of each component in a cotton fiber scouring solution containing protopectinase, α-amylase, and a surfactant as components, from the calculated dilution ratio to the scouring solution. A step of calculating the amount of the scouring replenisher to be replenished and the concentration of each component, and adding the calculated amount and concentration of the scouring replenisher to maintain the concentration of each component in the scouring solution constant A continuous enzymatic scouring process for cotton fibers comprising the steps of:

In a preferred embodiment, the dilution ratio is determined by the following formula (1):
Dilution ratio (%) = P _in × W _t {V− (P _out −P _in ) W _t } (1)
(Wherein, P _out pickup rate of scouring tank outlet (actually measured values), P _in scouring tank inlet pickup rate (measured value), V is the volume (L) (Found scouring tank) the, W _t is calculated by weight of the cotton fibers after t time from the start scouring (min) indicates (cotton fiber transfer speed × t time (min) × cotton fiber (weight / length)), respectively); Then, the amount (v) of the scouring replenisher and the concentration (c) of the optional component are determined by the following equations (2) and (3), respectively:
v (L) = (P _out −P _in ) W _t (2)
c (g / L) = {V × C ₀ − (V−v) × (1−dilution ratio) × C ₀ □ v (3)
(Wherein, C ₀ represents the initial concentration of any component in the scouring tank, and P _out, P _in, V, and W _t are the same as in formula (1)) is calculated by .

  In a further preferred embodiment, the scouring replenisher is added to the scouring solution at a rate of v / t (L / min).

  In another preferred embodiment, the scouring liquid further contains a cotton wax remover.

  According to the control method of the present invention, it is possible to continuously enzymatically scour cotton fibers with existing equipment using a protopectinase enzyme at the same efficiency as a conventional chemical method. In the scouring according to the method of the present invention, energy saving and environmental protection are considered, and a sufficient scouring efficiency is achieved without generating a strongly alkaline waste liquid.

  In the present invention, the “cotton fiber” refers to a raw cotton fiber product and a fiber product containing the raw cotton fiber, for example, a yarn, a woven fabric, a knitted fabric, and a nonwoven fabric. Raw cotton fibers are composed of cellulose and a primary membrane covering it. The primary membrane is based on pectin, cotton wax, and protein. The shape of the cotton fiber is not particularly limited, but the method of the present invention is preferably applied to a shape that is very long in only one direction (for example, a yarn or a woven fabric).

  In the present invention, the protopectinase contained in the scouring liquid for cotton fiber is used for removing pectin substances adhered to the cotton fiber, and any substance can be used as long as the object can be achieved. Can be. For example, pectin-degrading enzymes derived from Bacillus, Trichosporon, Aspergillus and the like can be mentioned. Among these, it is preferable to use a protopectinase having a pH optimum for a weak alkali (pH 8.0) derived from Bacillus, in that the cotton fabric is less damaged and the scouring efficiency is good.

  The content of protopectinase in the scouring solution is preferably from 0.001 g / L to 100 g / L, and more preferably from 0.2 g / L to 2.0 g / L, in that scouring can be performed efficiently. .

  The enzymatic activity of protopectinase in the scouring solution is preferably from 10 U / ml to 5000 U / ml, more preferably from 100 U / ml to 500 U / ml, from the viewpoint of economic viability.

  The α-amylase contained in the scouring liquid for cotton fiber in the present invention is used for decomposing and removing starch-like substances adhering to cotton fiber, and any substance can be used as long as such an object can be achieved. Can also be used. For example, those derived from plants and those produced by microorganisms can be used. Plant-derived ones include, for example, malt-derived ones. Examples of those produced by microorganisms include those produced from koji mold or bacteria. Among them, it is preferable to use α-amylase derived from Bacillus bacterium from the viewpoint of economical implementation. It is preferable to use α-amylase that is compatible with the above-mentioned protopectinase, that is, one that does not inhibit the activity of protopectinase and that retains a certain activity even under the optimal reaction conditions of protopectinase. Examples of such α-amylase include “Biotex N-25” (manufactured by Nagase ChemteX Corporation) and “α-starch enzyme 7658” (manufactured by Enzyme Pharmaceutical Factory in Kudai City, Hebei Province, China).

  The content of α-amylase in the scouring solution is preferably 0.05 g / L to 40 g / L, and more preferably 0.5 g / L to 5 g / L.

  The enzyme activity of α-amylase in the scouring solution is preferably from 1.5 U / ml to 1,200 U / ml, more preferably from 15 U / ml to 150 U / ml.

  In the present invention, the surfactant contained in the cotton fiber scouring solution is used for the purpose of improving the scouring efficiency by removing oils and fats attached to the cotton fiber, and any surfactant can be used as long as the object can be achieved. Can also be used. For example, ionic surfactants, nonionic surfactants, combinations thereof, and the like can be mentioned. Specific examples of the ionic surfactant include Sunmol PNT (anionic, manufactured by Nichika Chemical Co., Ltd.). Specific examples of the nonionic surfactant include Sunmol NPN (non-ionic). Ionicity, manufactured by Nikka Chemical Co., Ltd.). It is preferable to use a nonionic surfactant in that the enzyme activity is hardly inhibited.

  The content of the surfactant in the scouring liquid is preferably 0.5 g / L to 20 g / L, and more preferably 2 g / L to 10 g / L.

  In the present invention, the scouring liquid for cotton fibers may contain a cotton wax removing agent. The cotton wax removing agent is used for the purpose of removing wax attached to the cotton fiber, and any material can be used as long as the purpose can be achieved. Examples thereof include silicone oils, modified silicone oils, alkyl sulfosuccinate salts, and emulsions of anionic surfactants of polyhydric alcohol fatty acid esters. The term "modified silicone oil" as used herein refers to a product in which a polyether or the like is introduced into the main chain of the silicone molecular skeleton in order to increase hydrophilicity. In the case of a one-pack type scouring solution described later, it is preferable to use one that does not easily inhibit the enzyme activity in the scouring solution.

  The content of the cotton wax removing agent in the scouring liquid is preferably 0.1 g / L to 40 g / L, and more preferably 2 g / L to 10 g / L, since the subsequent dyeing step can be performed without any problem. Is more preferred.

  In the present invention, the scouring liquid for cotton fiber may further contain, as other components, a chelating agent, an enzyme stabilizer, an enzyme activator, a bleaching aid and the like.

  Cotton fiber scouring liquid is generally added to water with protopectinase, α-amylase, a surfactant, and, if necessary, a cotton wax remover and other components until it becomes uniform at a temperature of 40 ° C. or less. It is made by mixing. The mixing order is not particularly limited. When a cotton wax-removing agent is contained, from the viewpoint of the stability of protopectinase, a two-pack cotton consisting of a main agent containing α-amylase, a surfactant and protopectinase, and an auxiliary agent containing a cotton wax-removing agent It is preferable to use a scouring liquid for fibers. In the case of this two-pack cotton fiber scouring liquid, α-amylase, surfactant, and protopectinase are mixed at a temperature of 40 ° C. or lower until uniform, and separately from this, an auxiliary solution containing a cotton wax removing agent is used. It is prepared by dispersing the agent in water at a temperature of 40 ° C. or lower. The main agent and the auxiliary may be used by mixing at the time of using the scouring liquid, or, for example, only the main agent is put in the refining liquid, and the auxiliary is put in the bleaching liquid used later, and separately. May be used.

  Using the cotton fiber scouring solution, the cotton fiber is usually scoured as follows. First, the cotton fibers are burnt and washed with water and hot water. Next, when using a one-pack type scouring solution or a scouring solution in which a main agent and an auxiliary agent are mixed immediately before use, the cotton fibers are immersed in a scouring solution for cotton fibers (room temperature), and a warming bath (55 ° C. to 70 ° C.) For 5 minutes to 2 hours, washing with hot water several times, and then performing normal bleaching treatment. When the two-pack type scouring liquid is used separately, the cotton fiber washed with water or hot water is immersed in a scouring liquid containing the main agent (room temperature), and is heated for 5 minutes to 2 hours in a warm bath (55 ° C to 70 ° C). After keeping it warm and washing with hot water several times, it is immersed in a bleaching solution containing an auxiliary agent to perform bleaching treatment. In this way, the scouring of the cotton fibers is performed.

  According to the continuous enzymatic scouring method for cotton fibers of the present invention, scouring of cotton fibers can be performed continuously. Continuous scouring does not immerse cotton fibers in a scouring solution in a batch manner, but once immerses cotton fibers in a scouring solution tank, then brings it to a heat insulation tank and performs scouring while moving it in the heat insulation tank. That means.

  In order to continuously perform scouring, it is necessary to measure the change in the concentration of each component in the scouring liquid and maintain the concentration of each component. Accordingly, the method of the present invention comprises a step of calculating a time-dependent dilution rate of each component in a cotton fiber scouring solution containing protopectinase, α-amylase, and a surfactant as components, from the calculated dilution rate. Calculating the amount of the scouring replenisher to be replenished to the scouring solution and the concentration of each of the components, and adding the scouring replenisher in the calculated amount and concentration at regular intervals or at a constant rate; And the step of keeping the concentration of each component in the solution constant. The scouring replenisher contains the same components as the scouring replenisher described above, but their concentrations and amounts are determined according to the method of the present invention.

The dilution ratio is calculated by the following equation (1):
Dilution ratio (%) = P _in × W _t {V− (P _out −P _in ) W _t } (1)

In the formula, P _out refers to a pickup rate (actually measured value) at the outlet of the scouring liquid tank. The pickup rate at the outlet of the scouring liquid tank is the water content (% by weight) after the cotton fibers immersed in the scouring liquid tank are squeezed at the outlet of the scouring liquid tank. P _in refers scouring tank inlet pickup rate (measured value). The pickup rate at the inlet of the scouring liquid tank is the water content (% by weight) after the cotton fiber before scouring is squeezed at the inlet of the scouring liquid tank. V is the volume (L) (actually measured value) of the scouring liquid tank. W _t is the weight of the cotton fiber after the time t (minute) from the start of the scouring (the moving speed of the cotton fiber × t time (minute) × (weight / length) of the cotton fiber). Before performing continuous scouring, the dilution rate can be calculated by setting the moving speed of the dough in advance and measuring the pickup rates at the inlet and outlet of the scouring liquid tank. The pickup rate is obtained by taking out the dough of an arbitrary area, measuring the weight as it is and after drying, and using the following formula:
Pickup rate (w / w%) = (water content in dough / dough weight) × 100

The amount (v) of the scouring replenisher and the concentration (c) of the optional component are calculated by the following equations (2) and (3), respectively:
v (L) = (P _out −P _in ) W _t (2)
c (g / L) = {V × C ₀ − (V−v) × (1−dilution ratio) × C ₀ □ v (3)

Wherein C ₀ indicates the starting concentration of any component in the scouring bath and P _out , P _in , V, and W _t are the same as in equation (1) above.

  By continuously adding the scouring replenisher having the concentration c of an arbitrary component obtained by the above formula at a constant interval or at a constant speed v / t (L / min), each component in the scouring solution tank is added. Can be kept constant. Therefore, it is possible to maintain the effect of scouring. By setting the concentration in advance, the flow rate from the scouring replenisher tank can be easily controlled by a computer program.

  Hereinafter, the present invention will be described with reference to Examples, but it goes without saying that the present invention is not limited to these Examples.

(Example 1)
In purified water, protopectinase Nagase 1.5 g / L (manufactured by Nagase ChemteX Corporation, trade name: XP-534), α-amylase 4 g / L (manufactured by Chugoku Keidai Enzyme Co., Ltd., trade name: BF-7658), Non-ionic surfactant 2g / L (Nichika Chemical Co., Ltd., trade name: Sunmol NPN), cotton wax remover 5.0g / L (China Sengomo Chemical Co., Ltd., trade name: CGF), and NaCl 2g / L Was added and mixed at room temperature until uniform, and the pH was adjusted to 7.0 to 8.0 to prepare a scouring liquid.

  A thin, dense plain weave fabric containing 100% cotton (unit weight: about 250 g / m), 10,000 m, is baked, washed with water, washed twice with hot water, and then washed with water. The conditions were determined and scouring was performed continuously.

The volume V of the scouring liquid tank used for scouring was 2170 L, and the moving speed of the dough was set at 40 m / min (the scouring time for a 10,000 m dough was about 4.2 hours). Pickup rate P _out of the scouring tank outlet is 140%, and the pickup rate P _in the scouring tank inlet was 84%. Therefore, if the arbitrary time t is 30 minutes and 60 minutes, the weight W _t of dough moving scouring liquid tank were respectively 300kg and 600 kg. When the maximum dilution rate of the enzyme in the scouring liquid tank at this time was calculated by the equation (1), it was 12.6% and 27.4%, respectively. The starting concentrations of protopectinase, α-amylase, surfactant, and cotton wax remover in the scouring solution in the scouring solution tank were 1.5 g / L, 4.0 g / L, 1.0 g / L, and 5 g / L, respectively. did. Using the maximum dilution rate of 27.4% after 60 minutes, the amount of the scouring replenisher to be replenished within one hour according to the formula (2) and the protopectinase concentration of the scouring replenisher according to the formula (3) were calculated. They were 337 L and 3.73 g / L, respectively. A scouring replenisher 337 × 4.2 = 1415 L was prepared, and this was continuously poured into the scouring solution tank at a rate of 337 L / 60 minutes = 5.62 L / min and added. %. The dough was temporarily immersed in the scouring solution while moving at a speed of 40 m / min, and an enzyme amount of 0.5 g protopectinase / kg dough or more was picked up (held by the dough), and then kept at 65 ° C. for 1 hour. After three washed with hot water, bleach solution (PLC3000 (Nicca Chemical Co., _{Ltd.) 2g / L, H 2 O} 2 12g / L, NaOH 4g / L, and the Saint-Maur NPN (Nicca Chemical Co., Ltd.) (2 g / L), followed by mercerizing.

  After the mercerization, the scouring degree (pectin removal rate%), glue removal rate (%), water absorption and dyeing degree were measured. Table 1 shows the results. FIG. 1 shows the time-dependent changes in protopectinase activity and α-amylase activity in the scouring solution tank.

The degree of scouring was expressed as pectin removal and measured as follows: untreated raw fabric and scoured dough were treated with 1% (w / v) NaOH and 0.1% (v / v) Sunmol BK- The pectin was immersed in a solution containing 57 (bath ratio 1:20), the remaining pectin was decomposed into free galacturonic acid by boiling, and the free galacturonic acid was quantified by the absorbance at 235 nm. The pectin removal rate was calculated by the following formula:
Pectin removal rate (%) = (Amount of free galacturonic acid in original fabric-Amount of free galacturonic acid in treated fabric) / Amount of free galacturonic acid in original fabric x 100%

The glue removal rate was calculated from the glue amount of the original fabric and the glue amount in the processed dough. The amount of paste was measured as follows: starch in the dough was liquefied with amylase (Nagase ChemteX Co., Ltd., trade name: Biotex L # 3000), extracted with water, and the extract was extracted. The amount of glucose was quantified by the anthrone method and converted to the amount of glue by the following formula:
Glue amount (mg / g dough) = glucose amount (mg / g dough) x conversion factor (0.9)
Therefore, the glue removal rate was calculated by the following formula:
Glue removal rate (%) = (Glue amount of original fabric-Glue amount of treated fabric) / Glue amount of original fabric x 100%

  The water absorption was measured by a drop water absorption measurement method and a Pyrek measurement method. In the drop water absorption measurement method, the permeation rate and permeation state of water drops dropped on the treated fabric were visually evaluated. In the Pyrek measurement method, one end of a vertically fixed dough was immersed in water, and the rate of rise of water by capillary action was measured.

  The fabric after the mercerization was dyed by an ordinary method using an active dye (Activated Blue BES: Active Red BES: Active Golden Yellow BES = 9: 1.6: 1.3 (manufactured by Shanghai Mandoku)). The dyeing degree was measured by an L value by a color difference meter (MODEL Z-1001DP: manufactured by Nippon Denshoku Industries Co., Ltd.) and a K / S value by a colorimeter (AU Color-NF: manufactured by Kurabo Industries, Ltd.). In addition, the elongation, weight loss, water shrinkage, and fastness of the processed dough were measured as follows. The strong elongation was measured in the vertical direction and the horizontal direction using an autograph (AG-5000D manufactured by Shimadzu Corporation). The weight loss rate was calculated by the ratio of the unit weight difference between the untreated dough and the treated dough to the unit weight of the untreated dough. The water shrinkage rate was calculated by the ratio of the shrinkage dimension of the vertical and horizontal sides to the dimension before washing, after the treated cloth was washed once with water and further dried. The fastness was measured in accordance with the standard test method JIS L 0842, 0849, 0848, 0844 A-2.

(Comparative Example 1)
A scouring treatment was carried out in the same manner as in Example 1 except that an alkali mixed solution (containing 40 g / L of NaOH and 10 g / L of a surfactant) was added instead of the scouring solution. The properties and the degree of staining were measured. Table 1 shows the results.

  As can be seen from Table 1, when scouring is controlled by the method of the present invention, the dough after scouring has the same level of water absorption and dyeability as in the case of the conventional chemical method (Comparative Example 1). Degree, strength and elongation, weight loss rate and water shrinkage rate were also equal to or higher than those of the chemical method. Further, as shown in FIG. 1, the activity of the enzyme in the scouring liquid tank was kept constant.

(Example 2)
In purified water, protopectinase Nagase 1.5 g / L (manufactured by Nagase ChemteX Corporation, trade name: XP-534), α-amylase 4.2 g / L (manufactured by Chugoku Keidai Enzyme Co., Ltd., trade name: BF-7658) , A nonionic surfactant 1 g / L (manufactured by Nikka Chemical Co., Ltd., trade name: Sunmol NPN), and 2 g / L of NaCl are added and mixed at room temperature until uniform, and the pH becomes 7.0 to 8.0. Was adjusted as described above to produce a scouring liquid.

  Approximately 9000 meters (unit weight is about 160 g / m) of thin and dense plain woven fabric containing 100% cotton is baked, washed with water, washed twice with hot water, and then washed with water. The conditions were determined and scouring was performed continuously.

  The volume V of the scouring liquid tank used for scouring was 2170 L, and the moving speed of the dough was set at 40 m / min (the scouring time for a 9000 m dough was about 3.75 hours). The pickup rate Pout at the outlet of the scouring liquid tank was 124%, and the pickup rate Pin at the inlet of the scouring liquid tank was 82%. Therefore, when the arbitrary time t was 60 minutes and 120 minutes, the weight W of the dough moved in the scouring liquid tank was 384 kg and 768 kg, respectively. When the maximum dilution ratio of the enzyme in the scouring solution tank at this time was calculated by the equation (1), they were 15.7% and 34.1%, respectively. The starting concentrations of protopectinase, α-amylase and surfactant in the scouring solution in the scouring solution tank were 1.25 g / L, 3.3 g / L and 0.8 g / L, respectively. Using the maximum dilution rate of 15.7% after 60 minutes, the amount of the scouring replenisher to be replenished within 2 hours was calculated by equation (2), and the protopectinase concentration of the scouring replenisher was calculated by equation (3). They were 161.3 L and 3.7 g / L, respectively. A scouring replenisher (161.3 × 3.75 = 605 L) was prepared and continuously added to the scouring solution tank at a rate of 161.3 L / 60 min = 2.68 L / min, and the concentration of each component was adjusted to the starting concentration ± 15. %. The dough was once immersed in the scouring solution while moving at a speed of 40 m / min. After picking up an enzyme amount of 0.5 g protopectinase / kg dough or more, the temperature was kept at 65 ° C. for 1 hour. After washing with hot water several times, bleaching treatment was performed with a bleaching solution containing 7.5 g / L of a cotton wax remover (trade name: CGF, manufactured by Sengomo Chemical Co., Ltd. China), and further, mercerizing was performed. The fabric after the mercerization was dyed using an active dye (active red BES: active gold yellow BES: active navy blue BET = 5.3: 1.5: 1 (manufactured by Shanghai Mandoku)) by a commonly used method. The evaluation was performed in the same manner as in Example 1. The degree of staining was visually observed.

(Comparative Example 2)
A scouring treatment was carried out in the same manner as in Example 2 except that an alkaline mixed solution (containing 40 g / L of NaOH and 10 g / L of a surfactant) was used instead of the scouring solution, and the pectin removal rate, glue removal rate, and water absorption The properties and the degree of staining were measured. Table 2 shows the results.

  As can be seen from Table 2, when scouring is controlled by the method of the present invention, the dough after scouring shows the same level of water absorption as in the case of the conventional chemical method (Comparative Example 2), and the dyeability is equivalent to that of the chemical method. Met.

  By the continuous enzymatic scouring method of the present invention, a cotton fiber fabric having properties such as water absorption and dyeing properties equivalent to those of the conventional chemical method can be obtained. This method enables continuous scouring in consideration of energy saving and environmental protection even with the existing equipment, and can be widely used for scouring cotton fibers.

It is a graph which shows the time-dependent change of protopectinase activity and (alpha) -amylase activity in a scouring liquid tank.

Claims (4)

  A method for continuous enzymatic scouring of cotton fiber, in which a step of calculating a dilution ratio of each component over time in a scouring solution for cotton fiber containing protopectinase, α-amylase, and a surfactant as components was calculated. A step of calculating the amount of the scouring replenisher to be replenished to the scouring solution and the concentration of each component from the dilution ratio, and adding the scouring replenisher in the calculated amount and concentration, and adding each component in the scouring solution. Maintaining a constant concentration of The dilution ratio is determined by the following formula (1):
Dilution ratio (%) = P _in × W _t {V− (P _out −P _in ) W _t } (1)
(Wherein, P _out pickup rate of scouring tank outlet (actually measured values), P _in scouring tank inlet pickup rate (measured value), V is the volume (L) (Found scouring tank) the, W _t is calculated by weight of the cotton fibers after t time from the start scouring (min) indicates (cotton fiber transfer speed × t time (min) × cotton fiber (weight / length)), respectively); Then, the amount (v) of the scouring replenisher and the concentration (c) of the optional component are determined by the following formulas (2) and (3), respectively:
v (L) = (P _out −P _in ) W _t (2)
c (g / L) = {V × C ₀ − (V−v) × (1−dilution ratio) × C ₀ □ v (3)
(Wherein, C ₀ represents the initial concentration of any component in the scouring tank, and P _out, P _in, V, and W _t are the same as in formula (1)) is calculated by The method of claim 1.   3. The method of claim 2, wherein the scouring replenisher is added to the scouring liquor at a rate of v / t (L / min).   The method according to any one of claims 1 to 3, wherein the scouring liquid further contains a cotton wax removing agent.

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