JPH01314782A - Modification of silk - Google Patents

Abstract

PURPOSE:To obtain a modified silk fiber having excellent crease resistance and light resistance and good feeling by treating silk with a hydrophilic chitin or said chitin and a 2-hydroxybenzophenone compound nucleus-substituted with hydrophilic group. CONSTITUTION:Silk fiber is modified to have especially excellent crease resistance and feeling by immersing a silk fiber in a solution containing a hydrophilic chitin produced by imparting a chitin with hydrophilic nature. Light resistance of silk fiber can be improved by the treatment with said chitin and a 2- hydroxybenzophenone compound nucleus-substituted with hydrophilic group. Polymerization treatment of silk with a solution containing said chitin and a radically polymerizable hydrophilic monomer (e.g., acrylic acid and methyl acrylate) gives modified silk having especially excellent feeling. The feeling, crease resistance, light resistance, etc., of silk can be improved at the same time without deteriorating the characteristic features of silk by the treatment with the above components.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for modifying silk that can impart excellent texture, wrinkle resistance, light resistance, etc. to silk.

[Prior Art] Although silk inherently has excellent flexibility and drapability, it is known to be inferior in wrinkle resistance, light fastness, and texture.

Conventionally, the following processing methods have been employed to improve wrinkle resistance and light resistance.

(1) Melamine formalin resin, urea formalin resin,
A method of resin processing using epoxy resin, etc.

(2) stannous chloride, tannic acid, magnesium sulfate,
A method of treatment with basic lead acetate, etc.

In addition, processing methods for improving the texture include (3) a processing method of graft polymerizing non-hydrophilic vinyl monomers such as acrylonitrile, methyl methacrylate, and styrene; (4) hydroxyethyl acrylate, methacrylate, or hydroxypropyl acrylate. Alternatively, a processing method has been proposed in which hydrophilic acrylic radically polymerizable monomers such as methacrylate, acrylamide, and methacrylamide are used and these monomers are graft-polymerized onto silk using a radical initiator (Japanese Patent Publication No. 4 [1-28684]). has been done.

In particular, when silk is subjected to radical graft polymerization of hydrophilic acrylic radically polymerizable monomers alone or in combination, or polyfunctional radically polymerizable monomers such as ethylene glycol dimethacrylate and ethylene bisacrylamide, the texture of silk is significantly improved. is also known.

[The problem that the invention tries to solve! ] However, when trying to improve wrinkle resistance and light resistance using processing methods (1) or (2), the texture deteriorates, and (3) to (4)
) If you try to improve the texture using the processing method mentioned above, you will not be able to improve the wrinkle resistance or light fastness.

The object of the present invention is to provide a method for modifying silk that can improve wrinkle resistance and light resistance as well as texture.

[Means for Solving the Problems] That is, the present invention relates to a method for modifying silk, which is characterized by treating silk with hydrophilic chitin.

[Function] Although it is not yet clear why the method of the present invention improves the wrinkle resistance, light resistance, and texture of silk at the same time, hydrophilic chitin is a biopolymer and protein fibers such as silk Due to the strong adsorption power of various amino acids in the molecule to the polypeptide conjugate, it is incorporated into the silk fibroin, and the shape fixation caused by the hydrogen bonds of the numerous polyhydric alcohol groups in the hydrophilic chitinous molecules improves the texture and texture. It is presumed that it improves wrinkle resistance.

[Preferred Embodiment] The hydrophilic chitin used in the present invention is chitin that has been chemically treated to impart hydrophilicity, and the degree of deacetylation obtained by treating the acetyl groups of chitin with an alkali is 60.
% or more, especially 80 to 100% deacetylated products (deacetylated chitin), or chitin or various deacetylated chitins with different degrees of deacetylation are treated with chloroacetic acid, chloroacetic ester, etc. in the coexistence of an alkali. hydrolyzed carboxymethyl chitin ether salt, carboxymethyl alkyl ester chitin ether, carboxymethyl deacetylated chitin ether salt, carboxymethyl alkyl ester deacetylated chitin ether, or carboxymethyl alkyl ester of chitin or deacetylated chitin. Examples include one or more carboxymethyl ethers of chitin or deacetylated chitin that can be obtained, organic acid salts of deacetylated chitin, and the like. The molecular weight is approximately 10,000 to 500,000, which is appropriate; if it is too small, the effect will be low, and if it is too large, the inherent properties of silk will be impaired.

Silk may be treated with hydrophilic chitin by immersion in an aqueous solution of hydrophilic chitin, spraying, painting, or the like. An aqueous liquid of hydrophilic chitin can be prepared by dissolving hydrophilic chitin in water or an aqueous liquid. Some hydrophilic chitin substances are difficult to dissolve in neutral water, but in that case, acid can be added to the aqueous liquid to make it acidic. For example, carboxymethyl chitin ether salt is soluble in neutral water, and deacetylated chitin with a degree of deacetylation of 80% or more is soluble in acidic water. Furthermore, since carboxymethyl deacetylated chitin ether dissolves in neutral water and becomes acidic, other deacetylated chitins dissolve in this aqueous solution. Examples of the aqueous liquid include liquid mixtures of water and alcohols, esters, ketones, N-methylpyrrolidone, and the like. When dissolving hydrophilic chitin in an aqueous liquid, a variety of acids can be used as needed, including formic acid, acetic acid, propionic acid, lactic acid, malic acid, malonic acid, pyruvic acid, Adipic acid, succinic acid,
Examples include various organic acids such as citric acid, citric acid, and tartaric acid, and inorganic acids such as hydrochloric acid and nitric acid. Acidity is usually about pH 6 to 3.

The treatment temperature may be room temperature, and in the case of immersion treatment, it is usually 10~
It may be immersed for 200 minutes.

The target silks are unprocessed silk, silk processed with melamine-formalin resin, urea-formalin resin, epoxy resin, etc., silk treated with tannic acid or various salts, and non-hydrophilic or hydrophilic monopolymerized or multipolymerized silk. It may also be silk that has been graft-polymerized with a monomer.

Hydrophilic chitin is 0.005-0.5g per 1g of silk.
1, particularly preferably from 0.02 to 0.1 g.

Too little will have no effect, and too much will reduce the original properties of silk. The appropriate amount of the aqueous medium is 1 to 10 g of culm per 1 g of silk.

The present invention further relates to a method for treating silk with 2-hydroxybenzophenones which are nuclear-substituted with hydrophilic groups in addition to hydrophilic chitin.

The present inventors have also conducted extensive research on the yellowing of silk, and have discovered that the light that promotes the yellowing of silk is ultraviolet rays with a wavelength of 290 to 40 Or+m, and it is known that ultraviolet rays of that wavelength are absorbed. Focusing on 2-hydroxybenzophenones, which are antioxidants, we carried out nuclear substitution of 2-hydroxybenzophenones with hydrophilic groups in order to make them compatible with hydrophilic chitinous aqueous solutions.

2-Hydroxybenzophenones whose nucleus is substituted with a hydrophilic group used in the present invention refer to 2-hydroxybenzophenones in which one or more hydrogen atoms of the aromatic ring of 2-hydroxybenzophenone are substituted with a hydroxyl group, a carboxylic acid group,
It is substituted with one or more of an amide group, an alkoxy group, an amino group, a sulfonic acid group, etc., and as a result, it becomes soluble in an aqueous liquid. Specific examples include 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 2,2°4,4°-tetrahydroxybenzophenone, 2,4-dihydroxybenzophenone, 2-
Examples include hydroxy-4-methoxybenzophenone.

This 2-hydroxybenzophenone is 1 g per 1 g of silk.
~100 mg, preferably about 5 to 50 mg is used. The treatment may be performed by adding it to an aqueous solution of hydrophilic chitin to form a mixed aqueous solution, or separately before or after the treatment with hydrophilic chitin. Other treatment conditions may be the same as in the case of using hydrophilic chitin alone.

The present invention further provides the hydrophilic chitin and the hydrophilic radically polymerizable monomer, and if necessary, the hydrophilic group-substituted 2
This invention relates to a method for modifying silk by polymerizing it in a mixture with -hydroxybenzophenones in the presence of a radical initiator.

Hydrophilic radically polymerizable monomers are known to give excellent texture to silk, and the radically polymerizable monomer molecules include hydroxyl groups, alkyl ether groups, carboxyl groups, carboxylic acid ester groups, amino groups, amide groups, and N- It contains a hydrophilic group such as a substituted amide group. Specific examples include acrylic acid, methyl acrylate, methacrylic acid, methyl methacrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, acrylamide, methacrylamide, ethylene glycol dimethacrylate, trimethylolpropane trichloride. Examples include methacrylate, ethylenebisacrylamide, and ethylenebismethacrylamide.

When a hydrophilic radically polymerizable monomer is graft-polymerized onto silk in the presence of hydrophilic chitin, the polyhydric alcohol groups of the hydrophilic chitin molecules interact with the hydrophilic groups of the hydrophilic radically polymerizable monomer, resulting in hydrophilic properties. It is thought that a so-called hybridized graft polymer containing chitin uniformly at the molecular level can be used, and therefore it is presumed that it can be replaced with a product that has excellent wrinkle resistance, texture, and light resistance.

In the radical polymerization method, radiation, light, ultrasound, etc. can be used as a radical initiator, but azo-type or peroxy-type radical initiators, redox-type radical initiators using persulfates or cerium salts, and hydrogen peroxide can also be used. General radical polymerization methods such as a radical initiation system in which the polymer is heated under acidic conditions or in combination with the electromagnetic waves or iron salts are employed. Polymerization conditions vary depending on the radical initiation method, but are usually 1 to 5 hours at room temperature, 80 to 9
At a temperature of 5°C, the reaction may be carried out for about 0.5 to 1.0 hours.

The amount of hydrophilic radically polymerizable monomer per gram of silk is
It varies depending on the type of monomer, but usually 0.05 to 5.0
g, preferably 0.1 to 2.0 g, and the appropriate amount of the aqueous medium is about 10 to 100 g per 1 g of silk.

The amount of the radical initiator may be appropriately selected depending on the type and amount of the hydrophilic radically polymerizable monomer, but is usually about 0.1 to 10 mol% of the monomer.

Next, the method for modifying silk according to the present invention will be explained based on Examples, but the present invention is not limited to these Examples.

Example 1 In an Erlenmeyer flask with an internal volume of 100 m1, 50 m1 of water and 0 acetic acid were added.
, 1 ml and 50 mg of deacetylated chitin (degree of deacetylation: 80%) having the molecular weight shown in Table 1 were added, and the mixture was slowly stirred at room temperature for 120 minutes to prepare a treatment solution.

In this treatment solution, as shown in Table 1, raw silk cloth, II E
M A processed silk cloth (hydroxyethyl methacrylate (
IIEMA) grafted with 20% by weight) and epoxy treated with phenyl glycidyl ether (
1 g of silk (10% by weight) was soaked in the solution, left to stand at room temperature for 120 minutes, and then washed with water and dried.

The wrinkle resistance of the resulting treated silk fabric was evaluated according to JIS-1059-19.
Evaluation was made by the 85A method (wire method). In addition, the wrinkle resistance was measured by measuring the opening angle in the vertical direction and the horizontal direction, and the sum of both was defined as the wrinkle resistance (unit: degree).

The results are shown in Table 1.

[Left below] Table 1 = 13 - = 12 - As is clear from Table 1, deacetylated chitin treatment significantly improves the wrinkle resistance of unprocessed silk fabric, HEMA-treated silk fabric, and epoxy-treated silk fabric. I understand that

In addition, we conducted a sensory test on the texture with three adult women, and found that when the epoxy-treated silk cloth was processed and modified (experiment number 1),
1 to 13) are the best, followed by 11 HM A processed silk fabric (experiment numbers 6 to 8), unprocessed silk fabric (experiment numbers 2 to 4).
).

Example 2 50 ml of water was added to an Erlenmeyer flask with an internal volume of 100 ml. Add 0.1 ml of acetic acid and then add formic acid to bring the pl to 2.5.
0.2 g of HEMA and the amount of deacetylated chitin shown in Table 2 (degree of deacetylation 80%,
molecular weight 150,000) and 33% hydrogen peroxide solution 0.5ml
was added and stirred at room temperature to obtain a uniform treatment solution. 1 g of unprocessed silk cloth was immersed in this treatment solution and heated, kept at 80° C. for 1 hour to effect polymerization, washed with water and dried to obtain a HEMA-grafted deacetylated chitin-treated silk cloth.

The weight of the processed silk fabric obtained was measured to determine the grafting rate. In addition, the wrinkle resistance and texture were also examined in the same manner as in Example 1.

The results are shown in Table 2.

[Left below] From Table 2, it can be seen that grafting only +1 E M A reduces the wrinkle resistance, or coexisting hydrophilic chitin improves the wrinkle resistance without impairing the texture. I understand.

Example 3 In an Erlenmeyer flask with an internal volume of 100 m1, 50 m1 of water and 0 acetic acid were added.
．． 075ml and 50 mg of deacetylated chitin (degree of deacetylation, 80%, molecular weight, 150,000) were added, followed by addition of 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid in the amount shown in Table 3, and the mixture was heated at room temperature. The mixture was stirred to prepare a treatment solution.

1 g of silk cloth shown in Table 3 was immersed in this treatment solution, and at room temperature,
After being left for 60 minutes, it was washed with water and dried.

The yellowing resistance of the treated silk fabric obtained was examined in the following manner.

Treated silk cloth from a light source (500W xenon lamp) 4
．． After exposing it to light for 20 hours at a distance of 0 cm, the reflectance at 455 nm and 557 nm (
R and R5,7) are measured. The evaluation was performed using a yellowing index (Y, 1.) calculated using the following formula, with a standard white board (magnesium oxide board) set as 100.

Y,! ,=70/(1-R45,/R5,) In Table 3, ) IEMA processed oxidized soaping silk fabric is HE
M A processing (grafting rate 38% by weight) silk was heated at 80℃ for 20 minutes.
min hydrosulfide 5%, nonionic surfactant 5%
% ammonia aqueous solution (concentrated ammonia water 2ml/,
Q) is a silk cloth that has been immersed in water and has been drained and dried, and is a HEMA processed reduced soaping silk cloth. This refers to silk cloth that has been soaked in water containing ρ, then washed and dried.

[Margin below] As shown in Table 3, yellowing caused by ultraviolet rays can be greatly suppressed by adding a benzophenone derivative.

In addition, those of Experiment No. 3-2.3-4.3-6 had good wrinkle resistance and texture.

Example 4 50 ml of water was added to an Erlenmeyer flask with an internal volume of 100 ml. H.E.
Add 3 g of MAO, 0.05 g of deacetylated chitin (deacetylation degree 80%) with a molecular weight of 170,000 ft, and 0.03 g of 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, and add 33% hydrogen peroxide solution. 0, 5
ml and the pH was adjusted to 2.5 with formic acid. Add 1.0 g of unprocessed silk cloth to this solution and warm it to 80°C for 1.0 g.
Polymerization was carried out for a certain period of time, washed with water and dried to obtain a treated silk cloth.

The graft ratio, wrinkle resistance, and light resistance (ΔY, 1.) of this treated silk fabric were examined. The results are shown in Table 4.

- As shown in Table 4, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid and hydrophilic chitin were combined with HE.
By performing a radical polymerization treatment with a mixed solution blended in addition to 14 A, a product with excellent wrinkle resistance and light resistance can be obtained. In addition, the texture was also good.

[Effects of the Invention] According to the present invention, silk's weak points such as texture, wrinkle resistance, and light resistance are simultaneously improved without impairing the original characteristics of silk.

Claims (1)

[Claims] 1. A method for modifying silk, which comprises treating silk with hydrophilic chitin. 2. A method for modifying silk, which comprises treating silk with hydrophilic chitin and hydrophilic group-substituted 2-hydroxybenzophenones. 3. A method for modifying silk, which comprises polymerizing silk in a mixture of hydrophilic chitin and a hydrophilic radically polymerizable monomer in the presence of a radical initiator. 4 Silk modification processing characterized by polymerizing silk in a mixture of hydrophilic chitin, hydrophilic group-substituted 2-hydroxybenzophenones, and hydrophilic radically polymerizable monomers in the presence of a radical initiator. Law.