JPH1053964A - Fiber structure and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain moisture-absorbing and permeating fiber structure which is flexible and excellent in wet film strength by forming crosslinked protein- coated layer mainly comprising a protein and another polymer soluble in the common solvent to the protein on the surface of a fiber structure. SOLUTION: A protein such as gelatin and a water-soluble modified polyamide which is soluble in the same solvent as for the protein, for example, water in an amount of 10-100wt.% based on the gelatin, and in addition, a long chain epoxy crosslinking agent are formulated to prepare the objective coating solution. A fiber structure, for example, nylon twill-woven and dyed cloth treated with water-repelling agent is coated with the coating solution on its surface, dried, and heat-treated thereby forming crosslinked protein-coated film mainly comprising gelatin and water-soluble modified nylon on the surface of the fiber structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a fibrous structure. More specifically, the present invention relates to a fiber structure having excellent moisture absorption and moisture permeability, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, in the field of dry coating processing, a hygroscopic substance such as a protein is added to a resin having little hygroscopic property in itself in the field of dry coating processing in order to improve the hygroscopic property of a fiber structure. A way to do that was suggested.

[0003] However, a water-soluble substance having a very high hydrophilicity cannot be used as a hygroscopic substance because it causes a problem in durability due to elution during use or washing.

Further, when a large amount of a hygroscopic substance is added, the strength of the coating film is reduced, so that the amount of addition is also limited.

[0005] For this reason, in the dry coating film, the moisture absorption performance cannot be sufficiently improved, and when actually worn, a large amount of dew condensation due to perspiration occurs, and the moisture permeability is reduced and the stuffiness cannot be prevented. It is.

In recent years, a γ-carboxamide group, which is a glutamine residue of an amino acid of a protein, and an ε-
A method has been proposed in which a film is formed by crosslinking between amino groups with an enzyme.

[0007] The fiber structure produced by this method is
Since it is covered with a crosslinked film composed of a hygroscopic protein itself, it has excellent moisture permeability.

[0008] On the other hand, in the case of a crosslinked film of a single protein, hydrogen bonds are easily formed between the hydroxyl groups in the film, and therefore, there is a problem that the texture is remarkably hardened, especially in a dry state.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a low-cost fiber structure which is more flexible and has improved membrane strength when wet while maintaining the properties of a protein crosslinked film having excellent moisture absorption properties. It is to provide a manufacturing method thereof.

[0010]

The fibrous structure of the present invention comprises:
The following structure is provided to solve the above-mentioned problem.

That is, the fibrous structure is characterized in that at least one surface of the fibrous structure is covered with a coating mainly composed of a protein and a polymer soluble in the same solvent as the protein.

Further, a method for producing a fiber structure according to the present invention has the following constitution in order to solve the above problems.

[0013] That is, after coating the surface of the fiber structure with a solution containing a protein, a polymer soluble in the same solvent as the protein and a reactive crosslinking agent, the fiber structure is heat-treated. It is a method of manufacturing a product.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the fiber structure of the present invention will be described in detail.

In the present invention, the expression that at least one surface of the fiber structure is covered with a crosslinked film mainly composed of a protein and a polymer soluble in the same solvent as the protein means that at least one of the front and back surfaces of the fiber structure is used. One or both sides are in a state of at least one of adhesion and coating with the crosslinked film.

In the present invention, the crosslinked film mainly composed of a protein and a polymer soluble in the same solvent as the protein is a mixture of a heterogeneous polymer in the protein, In the mixed polymer,
Alternatively, it means a coating having few pinholes, which is a three-dimensional structure formed by the reaction of functional groups such as amino group, carboxyl group, and hydroxyl group present in the fiber structure and cross-linking each other.

In the present invention, a pinhole refers to a penetrated fine hole formed in a thin film.

The protein used in the present invention is not limited by its origin, and any protein such as a vegetable protein or an animal protein can be used.

Plant proteins include defatted plant seeds and proteins separated therefrom, ie, soybean proteins and wheat proteins. Animal proteins include milk proteins (such as casein), gelatin, collagen, keratin, and fibroin. And the like, and an enzyme,
These hydrolysates treated with an acid or the like can also be used.

As the solvent used in the present invention, any solvent can be used as long as it can dissolve the protein in a uniform viscosity solution so as to be coatable.

For example, water, lower alcohols, dimethylformamide, dimethylsulfoxide, and mixtures thereof can be used.

From the viewpoint of workability and the like, water is particularly preferably used, but in order to improve coatability, an organic solvent may be appropriately mixed and used.

In the present invention, the polymer soluble in the same solvent as the protein may be a stable substance that does not separate from the protein in the film-forming step and does not elute from the film after cross-linking. preferable. As such materials, many polymers such as modified polyesters, polyurethanes, and polyols having a hydrophilic functional group such as a hydroxyl group or an amino group can be used.

In particular, it is desirable that the polymer used has high hydrophilicity in order to maintain the excellent moisture-absorbing performance of the crosslinked protein film.

That is, it is desired that the protein has a similar structure to the protein and has high compatibility, and that it is preferably water-soluble, has a functional group, and can form a cross-link with the protein by a reactive cross-linking agent.

For example, polyamide or the like can be used in that it has a structure similar to that of a protein. In terms of having high hydrophilicity, a water-soluble polyamide obtained by condensation of a dicarboxylic acid with a diamine having a tertiary amine such as aminoethyl beverazine in the main chain, or a polyalkylene glycol residue in the main chain. So-called water-soluble nylon, such as water-soluble polyamide, can be preferably used.

As described above, the invasion of the heterogeneous polymer between the proteins makes it difficult for hydrogen bonds to be formed between and within the molecules of the protein, thereby preventing the hardening of the film.

Furthermore, in the mixed system, the movement of water is facilitated by the presence of fine domains in the film and the formation of an interface, and the hygroscopicity and the moisture permeability are higher than when a film of each constituent polymer alone is used. The effect of improving is also obtained. In the present invention, a domain refers to a uniform fine region generated by micro phase separation.

The fiber structure in the present invention includes wool,
It refers to natural fibers such as silk and cotton, synthetic fibers such as nylon, polyester, and acrylic, as well as those produced by blending, blending, and knitting, and specifically, fabrics.

Next, the method for producing the fiber structure of the present invention will be described below.

The fibrous structure of the present invention is produced by coating the surface of the fibrous structure with a solution containing a crosslinked protein, a polymer soluble in the same solvent as the protein and a reactive crosslinker, followed by heat treatment. .

A solution containing a protein and a polymer soluble in the same solvent as the protein is a protein concentration suitable for coating and film formation.
A solution prepared by adding a reactive cross-linking agent in an amount necessary for protein cross-linking to a solution adjusted to a solution viscosity.

From the viewpoint of workability, the solution is preferably an aqueous solution, but from the viewpoint of coatability, it is preferable to appropriately add an organic solvent such as dimethylformamide.

In order to make full use of the moisture-absorbing performance of the protein, it is preferable that the protein is contained in the coating and in the mixed solution in the same amount by weight or more as the polymer soluble in the same solvent.

On the other hand, from the viewpoint of the flexibility of the coating, it is preferable that the polymer soluble in the same solvent in the coating and in the mixed solution is contained in an amount of 10% by weight or more based on the weight of the protein.

From the viewpoint of both moisture permeability and flexibility, the polymer soluble in the same solvent in the coating film and in the mixed solution preferably contains 10% by weight or more and less than 100% by weight of the protein.

Further, from the viewpoint of film forming properties, the solid content concentration of the protein and the polymer soluble in the same solvent is preferably 5% by weight or more and 90% by weight or less in the mixed solution.
It is more preferable that the content be from 70% by weight to 70% by weight.

The reactive cross-linking agent used in the present invention is a polymer soluble in the same solvent as the protein,
Acid anhydride, if it can form a cross-link between at least one selected from the group consisting of a polymer and a fiber structure soluble in the same solvent as the protein,
It can be used irrespective of the type and number of functional groups such as dicarboxylic acid, diol, triol, isocyanate and diformalin. In view of the heat treatment temperature in the range in which the liquid stability and practicality in the film forming process are taken into consideration, and the process-passability at which sufficient processing efficiency can be obtained, an epoxy-based crosslinking agent is preferred. In consideration of the flexibility of the coating film, a long-chain epoxy crosslinking agent is more preferable. Further, when water is used as a solvent, a water-soluble long-chain epoxy crosslinking agent is particularly preferably used.

As the coating method, a coating method generally used for dry coating such as knife coating and gravure coating can be used for the fiber structure.

In the present invention, the solvent and the added organic solvent are evaporated by the heat treatment to form crosslinks in the coated mixture to form a film.

The heat treatment may be carried out at any temperature in consideration of the progress of the crosslinking reaction and the evaporation of the solvent and the organic solvent. Depending on the type of the reactive crosslinking agent used, it is preferable to dry at 60 ° C. or more for 1 minute or more. More preferably, heat treatment is performed at 80 ° C. or more for 2 minutes or more. The temperature and time required for film formation vary depending on the coating clearance,
More preferably, both drying and heat treatment are performed at 100 ° C. or higher.

In the present invention, the coating clearance refers to a gap provided between a cloth and a coating knife or the like in order to keep the thickness of a coating liquid film constant when coating, ie, continuously applying a mixed solution. In the present invention, the thickness is preferably in the range of 5 to 200 μm.

On the other hand, in order to prevent protein deterioration, drying,
The heat treatment is preferably performed at a temperature of 300 ° C. or lower, and is preferably performed within a total of one hour. Further, in consideration of process passability, processing cost, and the like, it is preferable that the treatment be completed by heating at 160 ° C. or lower and within 20 minutes.

According to the method of the present invention, a heat treatment is carried out using a reactive cross-linking agent to form cross-links, thereby increasing the cross-link density in the coating and preventing excessive swelling when wet, and A chemical bond is also formed between the film and the film to improve the adhesion and prevent the film from falling off.

Furthermore, even when the polymer soluble in the same solvent as the protein is water-soluble, the outflow of the water-soluble polymer during use or during washing can be prevented by forming crosslinks in the coating.

By following the above manufacturing method,
This makes it possible to exhibit high durability and high moisture absorption performance.

Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

[0048]

The present invention will now be described by way of Examples and Comparative Examples.
This will be described in more detail.

The durability, hygroscopicity, amount of dew condensation, moisture permeability, moisture permeability at the time of contact with water, water pressure resistance, peeling strength and bending resistance in the present invention were measured according to the following methods.

[Durability] The sample was immersed in hot water (90 ° C.) for about 5 minutes, and the presence or absence of dissolution and detachment of the coating film was observed.

When no dissolution or detachment of the coating was observed, it was evaluated as ○, and when observed, it was evaluated as x. (N number:
5) [Hygroscopicity] A test piece cut into a square of about 5 cm was put into a weighing bottle,
The sample was allowed to stand in a thermo-hygrostat set at 20 ° C. and 65% RH for 4 hours and weighed.

Subsequently, the sample was heated at 30 ° C. and 90% RH.
The sample was allowed to stand for 4 hours in a thermo-hygrostat, and then weighed.

The sample was dried in a blow dryer set at 110 ° C. for 1 hour, and the sample (test piece cloth + weighing bottle) and the weighing bottle were weighed to calculate the dry weight of the test piece.

From each of the weights determined above, the humidity change ΔMR was calculated as an index of hygroscopicity according to the following equation.

ΔMR (%) = [(weight of −weight)) / (weight of test piece)] × 100 (n: 3) [condensation amount] The weight of the test piece was measured.

100 m containing 100 g of hot water at 70 ° C.
A test piece was placed on the mouth of a 1-volume Erlenmeyer flask with the coating side down and fixed with a rubber band.

The Erlenmeyer flask was placed in a refrigerator set at about 4 ° C., allowed to stand for 1 hour, taken out, and the weight of the test piece with water droplets was measured.

Water droplets on the test piece were gently wiped off, and the weight was measured again.

From the weight obtained above, the amount of dew was calculated by the following equation.

Dew condensation amount (g / m ² · 1 hr) = (weight−weight) / S S: dew condensation area (m ² ) (n number: 3) [Moisture permeability] Measurement of moisture permeability specified in JIS Z 0208 Calcium chloride was put into the container until the 9th minute, the test piece was covered with the coating surface facing up, silicone packing was placed on the test piece, and a fastening ring was placed from above to fix and seal with a thumb screw.

The container was kept at a temperature of 40 ± 2 ° C. and a relative humidity of 90 ±
The container was placed in a 2% constant temperature / humidity bath, left for 1 hour, and then the container was taken out and immediately weighed.

The container was put again in the constant temperature and humidity chamber, left for 1 hour, taken out of the container, and immediately weighed.

From the weight determined above, the moisture permeability was calculated by the following equation.

Moisture permeability (g / m ² · 24 hr) = [(weight of −weight) × 24] / S S: moisture permeability area (m ² ) (n number: 3) [Water contact (at the time of dew condensation) Moisture Permeability] 20 in a moisture permeability measuring container specified in JIS Z 0208.
Then, the test piece was covered with the coating surface facing down, and the silicone packing and the fastening ring were fixed with a thumb screw and sealed.

The container was allowed to stand in a thermo-hygrostat set at 30 ° C. and 50% RH with the fabric side down, and the weight was measured after one hour.

The container was placed again in the constant temperature and humidity chamber, and the weight after one hour was measured.

From the above, the positive moisture permeability was calculated according to the following equation.

Dew condensation moisture permeability (g / m ² · 24 hr) =
(Weight-weight) × 24 / S S: moisture permeable area (m ² ) (n number: 3) [Water pressure resistance] A test piece with a coating surface facing up in a water resistance tester specified in JIS L 1092. Attached.

The water level was raised at a speed of about 1 cm / sec, and the pressure at which water droplets appeared at three different locations on the test piece was read.

(Number of n: 3) [Strength of peeling] An adhesive cloth tape was thermocompressed to the coating surface of the test piece with a dry iron while leaving one end.

A test piece was cut out according to the tape.

The end of the test piece was peeled off by about 1 cm, and a tensile test was performed using a tensile tester equipped with a self-recording device under the following conditions.

Grasping interval: 5 cm, pulling speed: 10 cm
/ Min, peeling measurement distance: 5 cm For each test piece, a total of 6 pieces, sequentially from the largest one showing the maximum value shown at the time of peeling, and three sequentially from the smallest one
The average value was calculated.

(Number of n: 3) [Flexibility] The texture of the test piece was evaluated as follows.
The sensory evaluation was performed by n number 1. The following were used as the protein, the polymer soluble in the same solvent as the protein and the reactive crosslinking agent used in the examples.

(1) Protein Purified gelatin powder manufactured by Nakarai Tesque Co., Ltd. (2) Polymer water-soluble nylon (A-90: hard water-soluble modified polyamide manufactured by Toray Industries, Inc.) (3) Reactive cross-linking agent Long-chain epoxy cross-linking agent ( DENACO manufactured by Nagase Kasei Kogyo Co., Ltd.
L EX-421: Diglycerol Polyglycidyl Ether) The following was used as the base fabric.

(1) Base cloth Water-repellent nylon-changed twill weave dyed cloth Weft, warp: Both 70 denier nylon filament yarns Weave density (finish): 153 × 106 [Example 1] 30% by weight of water-soluble nylon and gelatin An aqueous solution was prepared.

50 parts by weight of the aqueous solution were mixed (p
H = 6), the aqueous solution was warmed to 40 ° C.

Transglutaminase derived from actinomycete streptovertsilium was added so as to be 1.25 units per gram of gelatin to prepare a coating solution.

Knife coating was performed with a clearance of 150 μm.

After coating, the mixture was incubated at 37 ° C. for 2 hours, dried at 100 ° C., and a film was formed by inactivating the enzyme to obtain a fibrous structure.

As shown in Table 1, a fibrous structure having flexibility and very high moisture absorption performance was obtained.

[0082]

[Table 1] Example 2 A 30% by weight aqueous solution of water-soluble nylon and gelatin was prepared.

3 parts by weight of a reactive cross-linking agent was added to each 50 parts by weight of the aqueous solution to prepare a coating solution.

The base fabric was knife-coated with a clearance of 150 μm.

After drying at 110 ° C. for 1 minute,
Heat treatment was performed for a minute to form a film.

As shown in Table 1, while exhibiting excellent moisture permeability and further improving the dew condensation prevention property, it is an excellent fibrous structure having a small swelling and tackiness when wet and a strong resistance to external pressure. Was.

Table 1 also shows the results.

Example 3 A 37.5% by weight aqueous solution of water-soluble nylon and gelatin was prepared.

To 40 parts by weight of the aqueous solution was added 20 parts by weight of DMF and 3 parts by weight of a reactive crosslinking agent to prepare a coating liquid.

Thereafter, the same processing as in Example 2 was performed to form a film.

[0091] As shown in Table 1, the moisture permeability was as good as that of the water-based one, and a fibrous structure having significantly improved peel strength was obtained.

Comparative Example 1 A 37.5% by weight aqueous solution of water-soluble nylon was prepared.

3 parts by weight of a reactive crosslinking agent was added to 100 parts by weight of the aqueous solution of the above to prepare a coating liquid.

Hereinafter, a sample was prepared in the same manner as in Example 2.

As shown in Table 1, since no protein was added, the fiber structure was soft but had tackiness, and the fiber structure was inferior in moisture absorption performance as compared with the case where gelatin was added.

Comparative Example 2 A 37.5% by weight aqueous solution of gelatin was prepared.

3 parts by weight of a reactive crosslinking agent was added to 100 parts by weight of the aqueous solution of the above to prepare a coating liquid.

Hereinafter, a sample was prepared in the same manner as in Example 2.

As shown in Table 1, since a polymer soluble in the same solvent as the protein was not added, the fiber structure was not only extremely hard but also inferior in moisture permeability to that of nylon. It was a thing.

Comparative Example 3 A 37.5% by weight aqueous solution of water-soluble nylon and gelatin was prepared.

50 parts by weight of each of the aqueous solutions were mixed,
The coating solution was used.

Hereinafter, a sample was prepared in the same manner as in Example 2.

As shown in Table 1, since no crosslinking agent was added, the fiber structure was inferior in coating durability.

[0104]

Industrial Applicability According to the present invention, a low-cost fiber structure which maintains the properties of a protein cross-linked coating, which is extremely excellent in moisture absorption, and further enhances the softness and the membrane strength when wet, is improved. Is obtained.

Claims (8)

[Claims] 1. A fibrous structure characterized in that at least one surface of the fibrous structure is coated with a coating mainly composed of a protein and a polymer soluble in the same solvent as the protein. 2. The fibrous structure according to claim 1, wherein a polymer soluble in the same solvent as the protein in the coating contains from 10% by weight to 100% by weight of the protein. 3. A polymer which is soluble in the same solvent as the protein is cross-linked with at least one selected from the group consisting of proteins, fibrous structures and polymers soluble in the same solvent as the protein. The fibrous structure according to claim 1, wherein the fibrous structure is formed. 4. The polymer as claimed in claim 1, wherein the polymer soluble in the same solvent as the protein is a polyamide.
The fiber structure according to any one of the above. 5. The method according to claim 1, wherein the polymer soluble in the same solvent as the protein is a water-soluble modified polyamide.
5. The fiber structure according to 2, 3, or 4. 6. A fiber structure comprising coating a surface of a fiber structure with a solution containing a protein, a polymer soluble in the same solvent as the protein, and a reactive crosslinking agent, and then subjecting the fiber structure to a heat treatment. Method of manufacturing a product. 7. The method for producing a fibrous structure according to claim 6, wherein the polymer soluble in the same solvent as the protein is polyamide. 8. The method for producing a fiber structure according to claim 6, wherein the polymer soluble in the same solvent as the protein is a water-soluble modified polyamide.