JPH1193066A - Removal of colored component of vegetable fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bleaching process mild for both environments and fibers. SOLUTION: This method for removing the colored components of vegetable fibers comprises allowing a protease to act on the vegetable fibers in a process for treating a fiber product.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for removing coloring components from plant fibers. More specifically, the present invention relates to a method for removing a coloring component from plant fiber tissue using a protease in a process of treating a fiber product. The plant fibers to which the method of the present invention is applied include thread-like (spun yarn, processed yarn, etc.) and cloth-like (woven fabric, knitted fabric, non-woven fabric, etc.).

[0002]

2. Description of the Related Art In the process of treating a textile product, it is usually subjected to various processes such as a refining process, a bleaching process and a dyeing process in the form of spun yarn or woven fabric. Of these, the refining process is intended to remove primary impurities contained in the fiber and to clean it.
It is performed by immersing in a hot liquid or a hot liquid in which soap or soda is dissolved for an appropriate time, followed by washing with water.

[0003] The bleaching step means that the fiber contained in the fiber is oxidized or reduced to be decomposed and removed to make the fiber white. For example, bleaching powder, hydrogen peroxide, sodium peroxide, potassium permanganate, etc. Or an inorganic reducing agent such as sulfurous acid, sodium acid sulfite or hydrosulfite. However, treatment with these inorganic oxidizing agents and inorganic reducing agents may degrade the strength of the fiber itself, and requires enormous costs for wastewater treatment, causing problems in terms of environmental protection. What is needed is a bleaching process that is both environmentally and fiber friendly.

[0004] Recently, attempts have been made to use peroxidase, one of oxidases, as an oxidizing agent. However, the structure of the tissue of the plant fiber, the chemical structure of the coloring component present on the surface, the binding mode of the coloring component to the fiber surface, and the like have not been sufficiently elucidated.
In particular, the chemical structure and coloring mechanism of the coloring component are complicated, and furthermore, the coloring component itself is a trace amount of organic substances.
There is a problem that the analysis technology used for the analysis of a trace amount of inorganic substances cannot elucidate the components and the chemical structure. Therefore, in the method of bleaching using an enzyme such as peroxidase, it cannot be said that a treatment method sufficiently adapted to the mechanism of action of the enzyme, the chemical structure of the coloring component, the action, etc. has been established.

On the other hand, in recent years, a proteolytic enzyme has been used as an auxiliary agent for a laundry detergent component in a laundry detergent, and the proteolytic enzyme here forms sweat and dirt attached to clothes. A small amount is added to a laundry detergent for the purpose of removing protein components.

[0006]

Means for Solving the Problems The inventors of the present invention examined the possibility of a treatment step using a microorganism which is kind to both the environment and the fiber. As a result of various studies, it has been found that a protease that has not been used in a conventional process for treating plant fibers or the like is surprisingly effective for removing (bleaching) coloring components such as plant fibers. It was completed.

That is, according to the present invention, there is provided a method for removing a coloring component of plant fiber, in which a protease is acted on a plant fiber to remove a coloring component in a process of treating a fiber product.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A fiber product in the present invention is a final product in a form supplied to a general consumer, that is, a thread such as a sewing thread, a sewing thread, a lace thread, a woven fabric used as a material for underwear or clothing, etc. Knitting, non-woven fabric or these woven, knitting,
Includes finished fiber products such as underwear and clothing made of nonwoven fabric.

[0009] In the present invention, the plant fiber to be acted with a protease means a fiber derived from hemp, such as cotton, hemp, manila hemp, flax, jute, ramie, and the like. And fiber-like fibers such as woven, knitted and non-woven fabrics using these thread-like fibers. In the present invention, as long as the above-mentioned plant fiber is contained, a blended fiber with a synthetic fiber, a semi-synthetic fiber or a natural fiber may be used, and a woven fabric or a mixed fabric using such a blended fiber may be used.

In general, the process of treating a textile product includes various processes such as a refining process, a bleaching process and a dyeing process, as described above. It means a processing step performed as a part of the step. Specifically, it refers to the step of mainly removing the natural coloring components that are bonded to the fiber tissue, glue remaining in the target fiber, impurities and the like originally contained in the fiber, spinning, This also includes the case where dust, oil, etc. attached during the weaving process are simultaneously removed.

For example, as the plant fiber to be acted on by the protease in the present invention, the fiber may be a starch degrading enzyme (α-
(Amylase, β-amylase, saccharified amylase, etc.), and the fiber used in the spinning or weaving process may be a fiber from which the glue material has been removed. The fiber may be a fiber from which impurities and the like originally contained in the fiber are removed, or a fiber from which a glue material, impurities and the like are removed by allowing a starch-degrading enzyme and protopectinase to act on the fiber.

The protease in the present invention is an enzyme that hydrolyzes a peptide bond constituting a protein chain, and includes both a proteinase that degrades a protein and a peptidase that degrades a short peptide. When classified according to the mechanism of action of the protease, there are an endopeptidase that cuts the internal bond of a long peptide chain and an exopeptidase that cuts sequentially from the end of the chain. The protease of the present invention includes any of these. Furthermore, when classified according to the structure of the protease, a serine protease having serine as one of the main amino acids of the enzyme activity (eg, trypsin), a thiol protease having cysteine (eg, papain), a metal having zinc ion, etc. Various proteases such as proteases (eg, carboxypeptidase A, thermolysin, etc.) and aspartic proteases having aspartic acid (acidic proteases: pepsin, etc.) can be mentioned, and the present invention includes any of these. Also, when classified from the optimal pH at which the protease becomes active, those active in the acidic range such as pepsin, cathepsin, and koji mold-derived proteases, and those active in the weakly acidic to neutral range such as papain, bromelin, and ficin. , Those active in the neutral range such as denzyme, trypsin, those active in the neutral to weakly alkaline range such as chymotrypsin, proteinase K, subtilisin, nagase, those active in the alkaline range such as thermolysin, and the like. Including both. Among the above, in particular, proteases derived from microorganisms, for example,
Bacillus, Clostridium (Clostridiu)
m), Pseudomonasu, Aspergillus, Endomyces, Endomycopsis, Saccharomyces, Schizosaccomis
haromyces), Pichia, Hansenula (Hansen)
ula), Debarymyces, Hanseniaspora, Torulopsi
s), Candida, Kluyvers
omyces), proteases derived from microorganisms such as Galacttomyces, Rhizopus, Tritirachium and Trametes are preferred. The protease may be in the form of a commercially available powder or a liquid such as a culture solution obtained by culturing a microorganism, a filtration solution of the culture solution, or a concentration treatment solution. Further, as a filtered solution or a concentrated solution of the culture solution, an enzyme solution obtained by removing all or a part of solid components such as cells by centrifugation, filtration, dialysis, or the like, or this enzyme solution is further subjected to a usual method. For example, an enzyme solution obtained by diluting an enzyme obtained by purification by column chromatography or the like to an appropriate concentration may be used.

The protopectinase which can be used in the treatment step of the present invention includes, for example, the protopectinase proposed in Japanese Patent Application Laid-Open No. Hei 6-220772. Specifically, Trichosporon,
Endomyces, Endomycopsis, Saccharomyces, Schizosaccharomyces, Pichia, Hansenula, Debaryomyces, Hansenius spora, Torulopsis, Candida, Kluyveromyces, Bacillus, Aspergillus, Rhizopus and Trametes Enzymes produced by microorganisms of the genus that release pectin substances from cotton fibers.

The method for causing the protease to act on the plant fiber includes, for example, a method in which the optimum pH and the optimum temperature are appropriately selected depending on the kind of the protease to be used, and the protease is brought into contact with the plant fiber. Generally, in order to cause the protease to act on the plant fiber within the optimum pH range, the protease can be dissolved in a buffer and used. The type and concentration of the buffer for dissolving the protease is not particularly limited as long as it is a buffer generally used for retaining the enzyme. For example,
Examples of the buffer include various buffers such as an acetate buffer, a phosphate buffer, a borate buffer, a Menzel buffer, a Mackinbein buffer, a Good's buffer, a Tris buffer, and a Hepes buffer. In addition, p adjusted by this buffer solution
Since the optimum pH of H differs depending on the type of protease described below, it is preferable to adjust the H to various values in the range from acidic to alkaline. The concentration of the protease when dissolved in the buffer can be appropriately adjusted depending on the activity of the protease and the concentration of the buffer. For example, the concentration of the protease is 0.5 w / v% to 0. 001
w / v% (about 200 to 0.4 units / ml), more preferably 0.1 w / v% to 0.005 (40 to 2 units / m
1), more preferably 0.05 w / v% to 0.01.
w / v% (about 20 to 4 units / ml).

In order to bring the protease into contact with the plant fiber, the plant fiber is immersed in a buffer solution containing the protease and kept at a predetermined temperature for a certain period of time, or the protease fiber is coated or sprayed on the plant fiber. It is preferable that the buffer be kept in contact with the plant fiber at a predetermined temperature for a certain period of time. The dipping or contacting of the plant fiber with the buffer solution may be carried out by holding or standing in a stirring or vibration state or the like. The time for immersing or contacting the plant fiber can be appropriately adjusted depending on the amount of the plant fiber, the holding temperature, the activity or concentration of the protease, and the like, and for example, about 1 to 72 hours. In addition, the temperature at this time is a temperature at which the protease to be used is not inactivated, for example, a temperature range slightly raised from room temperature, more specifically, about 25 to 70 ° C., and more preferably 35 to 60 ° C. Temperature, more preferably about 45 to 55 ° C. The temperature at this time may be a constant temperature state, or may be changed by about two to four steps.

After the protease is allowed to act on the plant fiber, the protease may be inactivated, or may be directly washed with hot water or cold water about 1 to 10 times without deactivation, and dehydrated. It may be dried. In the above treatment step, the amylolytic enzyme and / or protopectinase may be simultaneously acted upon when the plant fiber is treated with the protease. For example, a buffer containing a protease and an amylolytic enzyme and / or a protopectinase is prepared, and first, an optimal pH of the amylolytic enzyme and / or a protopectinase is determined.
H, and then to the optimal pH of the protease.

In the present invention, although the details of the mechanism of action on the plant fiber are not clear, the coloring component bound to the surface of the plant fiber via a protein is cleaved by a protease, whereby such a coloring component is cleaved. Can be removed, whereby the whiteness of the fiber can be increased, and the color index, the yellow index, and the like can be reduced.

An embodiment of the method for removing a coloring component of plant fiber of the present invention will be described below. Example 1 Removal of coloring components of cotton cloth (cotton fiber) (1) Removal treatment of impurities and the like of cotton cloth In 30 liters (L) of 20 mM phosphate buffer (pH 8.0) at room temperature, warmin TE (Tokai Chemical Co., Ltd.) Made)
After 30 ml (0.1 V / V%) was added and mixed gently so as not to foam, the mixture was heated to 60 ° C. Set the solution temperature to 6
While maintaining the temperature at 0 ° C., a cotton cloth which had been subjected to a pretreatment for removing was put in the bath at a ratio of 20/1 (enzyme-buffer volume / cloth weight) and immersed for 15 minutes.

Thereafter, 437 ml of a protopectinase enzyme solution (arabinase activity, 24,000 units / ml)
Was added and shaken and stirred at 60 ° C. for 25 minutes. The reaction solution was quickly heated to 95 ° C. and kept for 5 minutes to inactivate the enzyme. After draining the enzyme solution, the cotton cloth is washed 5 times with warm water of 60 ° C. at a bath ratio of 20/1, and after centrifugal dehydration, 1 hour at 40 ° C.
Dry for 0 minutes.

(2) Treatment for removing colored components from cotton cloth In 25 ml of 100 mM acetate buffer (pH 4.0),
Trypsin (84 units / mg, Worthington Biochemica
l Co., acid protease) 1mg (0.004w /
v%) and mixed gently, then the cotton cloth obtained in the above (1) was immersed and allowed to stand at 36 ° C.

After 3 hours, the temperature was raised to 45 ° C., the mixture was shaken and stirred, and the mixture was further treated for 3 hours. After discharging the enzyme solution, the treated cotton cloth was washed 5 times by adding warm water at 40 ° C., dried, and then dried at 40 ° C. for 30 minutes. The whiteness of the cotton fabric after the coloring component removal treatment was measured. Table 1 shows the obtained results.
In addition, whiteness was measured as follows.

First, it is dried at 60 ° C. until there is no loss in weight. A 2 cm × 2 cm rectangular test piece is cut from the dried cotton cloth. Next, after wrinkles remaining on the dried test piece are pressed and flattened, the test piece is mounted on an integrating sphere of a color analyzer (model CA-3000, manufactured by Hitachi, Ltd.) under a light source D65, subjected to spectral measurement, and subjected to color space. Parameters of Y, x,
y, x _n, determine the y _n. The whiteness W is determined from these parameters according to the following equation <1>.

W = Y + 800 (x _n −x) +1700 (y _n −y) where Y is the tristimulus value Y in the xyz color system of the sample.
Values x, y are chromaticity in the chromaticity coordinates x _n, y _n is xyz color system of perfect diffuse reflection cotton in xyz color system of the sample.

Further, according to the following equation <2>, the color index T
Find w. _{Tw = 1000 (x n -x)} -650 (y n -y) ...... <2>

[0025]

[Table 1]

In the table, W represents the whiteness recommended by the International Commission on Illumination in 1986, and the greater this value, the greater the degree of whiteness. In addition, the color index Tw indicates that the green color becomes stronger as the value becomes larger in the positive direction, and the red color becomes stronger as the value becomes larger in the negative direction. As is clear from Table 1, (1)
The whiteness was improved by 30% or more with respect to the cotton cloth treated with, and a slight improvement was also observed in the yellow index. From this, it was confirmed that the coloring component of the cotton cloth could be removed by the treatment with the acidic protease.

The strength of the cotton cloth hardly changed by the acid protease treatment.

Example 2 Removal of coloring component of cotton cloth (1) Removal treatment of impurities and the like of cotton cloth A cotton cloth was treated in the same manner as in Example 1.

(2) Treatment for removing colored components from cotton cloth In 25 ml of 100 mM acetate buffer (pH 6.8),
100 mg (0.4 w / v%) of Denzyme (Denazyme: XP-353, manufactured by Nagase Seikagaku Corporation, neutral protease) was added,
After gently dissolving, soak the cotton cloth obtained in (1),
It stood still at 6 degreeC.

After 3 hours, the temperature was raised to 45 ° C., the mixture was shaken and stirred, and the mixture was further treated for 3 hours. After discharging the enzyme solution, the treated cotton cloth was washed 5 times by adding warm water at 40 ° C., dried, and then dried at 40 ° C. for 30 minutes. The whiteness of the cotton fabric after the coloring component removal treatment was measured. Table 2 shows the obtained results.
The whiteness was measured in the same manner as in Example 1.

[0031]

[Table 2]

As is clear from Table 2, for the original cloth,
The whiteness was improved by 22% or more, and the yellow index was also improved by 6%. From this, it was confirmed that the coloring component of the cotton cloth could be removed by the treatment with the neutral protease. Further, the strength of the cotton cloth hardly changed by the neutral protease treatment.

Example 3 Removal of coloring components of cotton cloth (1) Removal treatment of impurities and the like of cotton cloth A cotton cloth was treated in the same manner as in Example 1.

(2) Treatment for removing colored components from cotton cloth 100 mM Tris-HCl buffer (pH 9.0) 25
1 ml of proteinase K (Proteinase K: 19 units / mg, Wako Pure Chemical Industries, alkaline proteinase)
mg (0.004 W / V%) and gently dissolved.
The cotton cloth subjected to the bio-scouring treatment was immersed and left at 36 ° C.

After 3 hours, the temperature was raised to 45 ° C., the mixture was shaken and stirred, and the mixture was further treated for 3 hours. After draining the enzyme solution,
The treated cotton cloth was washed 5 times by adding warm water at 40 ° C., dehydrated, and then dried at 40 ° C. for 30 minutes. The whiteness of the cotton fabric after the coloring component removal treatment was measured. Table 3 shows the obtained results. The whiteness was measured in the same manner as in Example 1.

[0036]

[Table 3]

As is clear from Table 3, for the original cloth,
The whiteness was improved by 44% or more, and the yellow index was also improved by 10%. From this, it was confirmed that the coloring component of the cotton cloth could be removed by the treatment with the alkaline protease. Further, the strength of the cotton cloth hardly changed by the alkaline protease treatment.

Claims (4)

[Claims] 1. A method for removing a coloring component of a plant fiber, comprising the step of: causing a protease to act on the plant fiber to remove the coloring component in the step of treating the fiber product. 2. The method according to claim 1, wherein the protease is used in an amount of 0.5 w / v% to 0.0%.
The method for removing coloring components of plant fibers according to claim 1, which is used in an aqueous solution of 01% w / v. 3. The method according to claim 1, wherein the plant fiber is treated with an amylolytic enzyme before or before the protease is acted on.
3. The method for removing a coloring component of a plant fiber according to item 1. 4. The method for removing a coloring component of plant fiber according to any one of claims 1 to 3, wherein the protopectinase is acted on or before the protease is acted on the plant fiber.