JPH04100984A - Highly moisture-permeable synthetic leather - Google Patents

Abstract

PURPOSE:To obtain the title synthetic leather with favorable touch, excellent in moisture permeability, hygroscopicity and moisture releasability, and resistant to its surface staining by forming an openly porous film consisting of a specific ingredient-contg. mixed resin on the surface of a synthetic leather base, comprising fibrous matter or fibrous matter and synthetic resin. CONSTITUTION:The surface of (A) a synthetic leather base comprising fibrous matter consisting of natural or synthetic fiber or consisting of the fibrous matter and a synthetic resin such as polyurethane is coated with (B) an organic solvent solution of a mixed resin consisting mainly of polyamino acid urethane resin and fluorine-modified polyurethane resin(furthermore, blended with synthetic polyamino acid granules) to effect the forming of an openly porous film, thus obtaining the objective synthetic leather free from stickiness and with natural leather touch. Also, when the main component of the polyamino acid urethane is poly-r-methyl-L-glutamate and the content of the latter is 3-85wt.% based on the former, excellent moisture permeability, hygroscopicity and moisture releasability of the present synthetic leather will be realized.

Description

[Detailed Description of the Invention] [Industrial Application Field 1] The present invention relates to synthetic leather, and more specifically, the present invention relates to synthetic leather, and more specifically, the surface has a texture similar to that of natural skin, and has properties such as moisture permeability, moisture absorption, and moisture release properties. The present invention relates to synthetic leather which has functions and whose surface is resistant to staining.

[Prior Art] Since synthetic leather first appeared as a substitute for natural leather, many improved technologies have been proposed, and it has now become an indispensable material for uses such as shoes, balls, and clothing. On the other hand, however, in these applications, people often use the material in direct contact with the skin, and the feel of the surface is not fully satisfactory. That is, there has been a demand for synthetic leather that has a surface feel that does not feel strange when it comes into contact with the skin, does not feel sticky due to sweat, and has high moisture permeability, high moisture absorption, and high moisture release properties. At present, there is nothing that meets these requirements, but as a solution, polyurethane with hydrophilic groups introduced, polyurethane mixed and dispersed with leather powder, silicone-modified polyurethane, or polyamino acid urethane can be used as a surface film. Formed synthetic leather has been proposed. However, none of these methods is practically satisfactory; for example,
Synthetic leathers with hydrophilic group-introduced polyurethane or silicone-modified polyurethane formed as a surface film have various moisture permeability properties, but they have a sticky feel that is characteristic of polyurethane, especially when they come in contact with sweaty skin. This is a problem because it is large.

In order to improve this, synthetic leather has been proposed in which a surface film is formed by mixing and dispersing leather powder in polyurethane, but since the leather powder contains metal, white paint is highly colored. If the content of leather powder is too high, the functionality such as surface feel and moisture permeability will be satisfied, but the film strength will be low and the leather powder will fall off from the surface film when rubbed. However, it is not yet satisfactory. In addition, by mechanically forming through holes on the surface,
Breathable synthetic leather with a continuous porous surface film has been proposed, but it has the drawback that dirt adheres to the surface pores and is difficult to remove, making it easy to stain.

[Objective of the Invention] The object of the present invention is to improve these conventional drawbacks, to have a surface texture that does not feel uncomfortable with human skin, and to have excellent functionality such as moisture permeability, moisture absorption, and moisture release, and to meet the needs of human skin. The purpose of the present invention is to provide synthetic leather that can be provided with breathability and whose surface is resistant to staining.

[Structure of the Invention] The present invention is characterized in that a coating of a mixed resin mainly composed of a polyamino acid urethane resin and a fluorine-modified polyurethane resin is formed on the surface of a synthetic leather base made of 11ft material and a synthetic resin. In synthetic leather. Further, the mixed resin may be a mixed resin mainly composed of a polyamino acid urethane resin, a fluorine-modified polyurethane resin, and synthetic polyamino acid particles, or particles made of natural collagen instead of the synthetic polyamino acid particles. In other words, the mixed resin may be a mixed resin whose main components are particles consisting of a polyamino acid urethane resin, a fluorine-modified polyurethane resin, and natural collagen.

The fibers used in the present invention include known synthetic fibers, recycled fibers, nonwoven fabrics, knitted fabrics, and woven fabrics made of natural fibers.
Depending on the use of the synthetic leather, it can be appropriately selected from the characteristics necessary for it.

Known polymers can be used as the synthetic resin that is combined with these fibers to form the synthetic leather base.

Examples include polyurethane resin, vinyl chloride resin, vinyl chloride-polyurethane copolymer, SBR resin, and NBR81 resin. Synthetic leather substrates are formed from these fibers and synthetic resin, and there are two types: one in which the fibers are impregnated with synthetic resin, one in which synthetic fibers are further formed on the surface of this impregnated substrate, and one in which synthetic fibers are further formed on the surface of the impregnated substrate. Types made of synthetic resin are used. Furthermore, fibrous materials alone can also be used as synthetic leather substrates. These synthetic resins are combined with the fibrous material by a known molding method.

In other words, the known wet method involves impregnation or coating with a solution such as N,N-dimethylformamide and solidification by water immersion, or impregnation with a W/○ type emulsion in which water is dispersed in a solution or dispersion of an organic solvent such as methyl ethyl ketone. Alternatively, it is made into a porous composite by a dry method of coating and drying, a wet method using an aqueous emulsion, a dry method, etc. Of course, a non-porous composite may also be adopted. The polyamino acid urethane of the present invention formed on the surface of the synthetic leather substrate thus obtained is a copolymer of polyurethane and polyamino acid, and conventionally known polyamino acid urethanes can be used. The method for producing the polyamino acid urethane includes adding N to polyurethane.
There is a method of addition polymerizing -carboxy-α amino acid anhydride. As the polyurethane used here, known polyurethanes can be used. For example, polyurethane obtained by reacting an organic diisocyanate with a long-chain diol and a chain extender is typical.As the organic diisocyanate, alicyclic organic diisocyanates, aliphatic organic diisocyanates, aromatic organic diisocyanates, etc. can be used. As long chain diols, polyester diols, polyether diols, polyamide ester diols, polycarbonate diols, etc. can be used.
As the chain extender, compounds containing two active hydrogen atoms such as low-molecular glycols, low-molecular diamines, and low-molecular amino alcohols can be used, and polyurethanes made of mixtures thereof may also be used. These raw materials should be selected depending on the application. For example, in applications where hydrolysis resistance and discoloration resistance are required, the organic diisocyanate should be alicyclic organic diisocyanate or aliphatic organic diisocyanate. As the long chain diol, a polycarbonate diol or a polyether diol may be used.

N-carboxy- added to the above polyurethane
As the α-amino acid anhydride, natural hydrate of γ-methyl L-glutamate, or ethyl carboxylic acid at the γ position,
There are anhydrous forms such as propyl and butyl esters, and naturally hydrated forms of leucine. The polyamino Mt segment ratio obtained by these reactions is 3% to 85% by weight, preferably 10% to 60% by weight. If the polyamino acid segment ratio is less than 3% by weight, moisture permeability, moisture absorption, and moisture release properties cannot be satisfied. Furthermore, when the mixed resin is a mixed resin mainly composed of a polyamino acid urethane resin, a fluorine-modified polyurethane resin, and synthetic polyamino acid particles, the synthetic polyamino acid particles may fall off from the coating film. ,
When the mixed resin is a mixed resin whose main components are particles made of a polyamino acid urethane resin, a fluorine-modified polyurethane resin, and natural collagen, the disadvantage is that the particles made of the natural collagen fall off from the coating film, which is undesirable. . Furthermore, if the polyamino acid segment ratio exceeds 855% by weight, the elongation of the resulting coating film will be low and the mechanical strength against bending, kneading, stretching, etc. will be reduced, which is not preferable.

The polyamino acid urethane thus obtained is used as an organic solvent solution. As an organic solvent for dissolving polyamino acid urethane, methylene chloride, chloroform,
There are chlorinated aliphatic hydrocarbons such as 1,2-dichloroethane, but they are difficult to dissolve when the polyurethane segment ratio in the polyamino acid urethane is high. Since it is difficult to dissolve, it is best to avoid it as much as possible.

Preferred organic solvents include dioxane, N,N dimethylformamide, N,N-dimethylacetamide, N-
Polar organic solvents include methylpyrrolidone, methylethylketone, and tetrahydrofuran. When the organic solvent used is such a polar organic solvent, if the ratio of amino acid segments in polyamino acid urethane is 40% or more, it generally does not dissolve and tends to form a translucent gel-like substance. The amino acid segment ratio should be designed in consideration of the type of organic solvent used, its concentration, etc.

In the present invention, other synthetic resins or natural resins are mixed and dissolved in the thus obtained organic solvent solution of polyamino acid urethane in order to modify the properties of the obtained surface film. be able to. In this case as well, the polyamino acid segment ratio in the mixed resin is 3% to 85% by weight.
It is preferable that The fluorine-modified polyurethane resin used in combination with such a polyamino acid urethane resin is one in which a portion of the hydrogen elements in the urethane molecular structure is replaced with fluorine elements, and conventionally known resins can be used. These fluorine-modified polyurethane resins, like polyamino acid urethane resins, have the effect of not making you feel sticky due to sweat, and they also have a great antifouling effect against stains, which is a drawback when made into porous membranes, which will be described later. have. In addition, in the present invention, the surface film has functions such as moisture permeability, moisture absorption, and moisture release properties due to the effects of the polyamino acid urethane resin, while water repellency is imparted to the outermost surface due to the effect of the fluorine-modified polyurethane resin. Therefore, when it comes into contact with the skin, it can give a refreshing surface feel without a wet feeling. Therefore, the effect can be enhanced by having more fluorine-containing segments present on the surface of the coating film, so it is better to have the fluorine-containing segments present in the side chain of the polyurethane resin than in the main chain to prevent the sticky feeling. , it is easy to obtain effects such as antifouling. This is because the fluorine segments tend to be oriented on the surface during solvent drying during coating film creation.

In this way, synthetic polyamino acid particles can be dispersed and used in an organic solvent solution of a mixed resin mainly composed of a polyamino acid urethane resin and a fluorine-modified polyurethane resin.

The synthetic polyamino acid particles are polymer particles obtained by the method of addition polymerizing N-carboxy-α-amino acid anhydride described above. Examples of N-carboxy-α-amino acid anhydrides include natural hydrates of γ-methyl to glutamate, or ethyl carboxylic acid at the γ-position,
Naturally aqueous substances such as propyl and butyl esters, and naturally aqueous substances such as leucine. Regarding these polymerization methods, please refer to Polymer 30,365 (+973), Polymer 3
0.39 (1973), Polymer 30,357 (19
73) are known, and by applying mechanical force such as cutting or crushing the gel obtained by the reaction described in these methods, α→
Polymer particles obtained by these methods can be used in the present invention by structurally converting the structure to the β type to form particles that do not dissolve. Furthermore, in some cases, processing such as pulverization is performed to make the particles even finer. The smaller the particles, the larger the particle surface per unit weight, which makes it easier to obtain functional properties such as moisture permeability, water absorption, and moisture release properties of the resulting synthetic leather, and the smoother the surface feel of the synthetic leather, which is preferable. . The average particle size of the particles is preferably 20 μm or less, more preferably 10 μm or less.

Furthermore, as another embodiment, particles made of natural collagen may be used by being dispersed in an organic solvent solution of a mixed resin containing the polyamino acid urethane resin and fluorine-modified polyurethane resin as main components. Particles made of natural collagen are particles obtained from animal skin, hair, bone, etc. through various treatments. For example, currently
Industrially produced products include leather powder made by grinding chromium-treated leather at low temperatures, and leather, hair, bone, etc. that are chromium-treated and untreated. Particulate collagen is purified by removing excess components other than collagen such as fat through an enzymatic decomposition reaction. In the present invention, any of the above particles can be used, but it is preferable to use particles purified from skin, hair, bones, etc. that have not been subjected to any chromium treatment such as coloring or discoloration of the particles. In other words, since the particles crushed from the former chromium-treated leather are colored in chrome, it is difficult to use light colors such as white, and
When used, it tends to discolor due to light due to impurities such as fat.

On the other hand, collagen particles purified by biochemical reaction treatment without chromium treatment are colorless (white) particles, so they can be used for white purposes and are free of impurities such as fat. Therefore, there is almost no discoloration due to light, which is preferable. However, collagen purified through biochemical reaction treatment has high swellability in water and is easily degraded by proteolytic enzymes such as amylase, so the molecules have been cross-linked through chemical reactions. is preferred. Particles made of such natural collagen are, in some cases, subjected to a treatment such as pulverization to make them even finer particles. The smaller the particle diameter is, the more preferable it is, as in the case of the synthetic polyamino acid particles.

A mixed resin containing such a polyamino acid urethane resin, a fluorine-modified polyurethane resin as a main component, a mixed resin in which the synthetic polyamino acid particles are mixed and dispersed, or a mixed resin in which particles made of natural collagen are mixed and dispersed. The cosmetic properties of the resulting coating film can be enhanced by adding a coloring agent such as a pigment or dye to the organic solvent solution, as the case may be. Furthermore, antioxidants, NOx gas discoloration inhibitors, various deterioration inhibitors, and the like can also be added in order to obtain a good surface film.

An organic solvent solution of a mixed resin mainly composed of a polyamino acid urethane resin and a fluorine-modified polyurethane resin obtained in this way is applied to the surface of a synthetic leather substrate and dried to form a coating film. Surface formation methods include spray coating,
Known methods such as gravure coating, knife coating, roll coating, and lamination using release paper can be employed.

Depending on these application methods, the concentration of the mixed solution may be adjusted to the optimum viscosity.If the coating thickness is insufficient after one application, repeat application and drying. Adjust to the target coating thickness.

The synthetic leather thus obtained has a surface feel that does not feel strange when a person comes into direct contact with the skin, does not feel sticky due to sweat, and has high moisture permeability, high moisture absorption, and high moisture release properties. The above functional properties can be significantly enhanced. As a method for obtaining a porous coating film, a known method such as a wet method in which the mixed resin solution is applied to the surface of the synthetic leather substrate and then the solvent is extracted by propulsion can be adopted, but particularly effective methods include: There is a phase fraction 1111 solidification method. This method involves adding, as a phase separation nucleating agent, to the mixed organic solvent solution a compound which has a limited solubility and is highly crystalline and precipitates into fine particles when the organic solvent evaporates. This is a method of dissolving it. For example, by applying an organic solvent solution of the mixed resin using N,N-dimethylformamide as an organic solvent and urea as a phase separation coagulation nucleating agent to the surface of a synthetic leather substrate and drying it, a porous coating film can be formed. can get. In some cases, even better quality porous material can be obtained by washing this material with water to extract urea.

In addition, as mentioned above, synthetic polyamino acid particles or natural collagen particles dispersed in an organic solvent solution of a mixed resin can be used to form a coating film on the surface of the synthetic leather substrate used in the present invention. However, the coating film is made of polyamino acid segments of amino acid urethane and synthetic polyamino acid particles, or natural collagen, which have excellent mechanical strength and are highly elongated even when mechanical forces such as bending and rubbing are applied. Since the particles have affinity due to the same amino acid molecular structure, there is no whitening or shedding of synthetic polyamino acid particles or particles made of natural collagen. Therefore, the amount of synthetic polyamino acid particles or natural collagen particles to be added to polyamino acid urethane (solid) can be selected from a wide range. The difference between the polyamino acid urethane in the total solid content and the polyamino acid segments of particles made of synthetic polyamino acid particles or natural collagen greatly affects the surface texture and functional properties of the resulting coating film. By increasing the amount of amino acid particles or particles made of natural collagen added, a coated film rich in functional properties with a large amount of polyamino acid segments can be obtained. In other words, when synthetic polyamino acid particles or particles made of natural collagen are used in combination with other synthetic resins such as polyurethane without using polyamino acid urethane, the amount of particles added must be adjusted to prevent the particles from falling off. Since there are limitations and the amount thereof is small, it is difficult to obtain surface properties rich in functional properties, which is the objective of the present invention. In addition, the surface film made only of polyamino acid urethane,
When the ratio of polyamino acid segments is high, a film having the functional properties targeted by the present invention can be obtained, but the resulting coating film has low elongation, resulting in poor mechanical durability such as bending. unable to achieve the goal.

The total weight of the polyamino acid segment in the polyamino acid urethane constituting the surface film of the present invention and the synthetic polyamino acid particles or particles made of natural collagen is 20% by weight based on the total solid content. The content is preferably 40% by weight or more, and more preferably 40% by weight or more.

However, it is not limited to these numbers.

Since the synthetic leather thus obtained has a porous coating on its surface made of a mixed resin mainly composed of a polyamino acid urethane resin and a fluorine-modified polyurethane resin, it is breathable. Compared to synthetic leather that has a membrane on its surface, it not only has a surface feel that is similar to human skin, but also has much superior functional properties such as moisture permeability, moisture absorption, and moisture release. However, on the other hand, since the surface is porous, there are problems with ease of staining and water resistance during use, but the surface of the present invention is made of fluorine-modified polyurethane that has oil and water repellency. So it doesn't get dirty easily.
Moreover, when it becomes dirty, it is easy to remove the dirt and has a certain degree of water resistance. Therefore, the mixing ratio of polyamino acid urethane resin and fluorine-modified polyurethane resin depends on the type of fluorine-modified polyurethane resin, but the ratio is preferably 10% to 70% from the viewpoint of antifouling properties, and when making it more porous. For this purpose, the proportion of fluorine-modified polyurethane resin may be increased.

As described above, by appropriately selecting the materials constituting the synthetic leather of the present invention depending on the use of the synthetic leather, these functional characteristics effects can be further enhanced. For example, when designing an upper material for shoes, a base fabric such as rayon or cotton with high hygroscopicity is used as the fiber that makes up the synthetic leather base, and the surface film used in the present invention is formed as the synthetic resin. Since the surface film is formed porous using a polyamino acid urethane resin, a 1:1 mixed resin of a polyamino acid urethane resin and a fluorine-modified polyurethane resin may be used. Furthermore, particles made of polyamino acid urethane and synthetic polyamino acid particles or natural collagen that form a surface film are used as the synthetic resin, and the surface film is made of polyamino acid urethane resin and synthetic polyamino acid particles or natural collagen as a porous material. approximately 45:4 of the particles
A 5:10 mixed resin may be used. In other words, the sweat that emanates from the feet is absorbed from the highly hygroscopic back surface, and then evaporated to the outside through the porous surface membrane, which has excellent moisture permeability, moisture release, and stain resistance, making the shoes feel less stuffy on the feet. can be obtained.

In this manner, the materials constituting the present invention can be appropriately selected depending on the intended use.

[Example] Hereinafter, the present invention will be explained in detail with reference to Examples.

In addition, "part j" and "%" in the examples are based on weight, and the characteristic measurement values were obtained by the following method.

(a) Moisture permeability (1
Expressed as (+/-・hr).

(0) Moisture absorption When left in an atmosphere with a temperature of 23°C and relative humidity of 30% for 1 hour, and then left in an atmosphere with a temperature of 23°C and relative humidity of 80% for 30 minutes! (g/m).

(10 Moisture release after leaving for 1 hour in an atmosphere with a temperature of 23°C and a relative humidity of 80%, and then leaving for 30 minutes in an atmosphere with a temperature of 23°C and a relative humidity of 30%, expressed as m <g/rd>.

B) Air permeability A value measured using a Gurley densometer according to the method of JIS P8117, expressed as the time (seconds) required for 50 cc of air to pass through.

(e) Resistance to nitrogen oxide gas denaturation It is expressed as a gray scale judgment according to the strong test method of JIS LO855.

(f) Stain Resistant Tobacco Ash (Mild Seven) ground in a mortar with a diameter of 36IIIn, rubbed with the middle finger 25 times clockwise and 25 times counterclockwise, then wiped with absorbent cotton to obtain Grade 5 is expressed on a scale of 1 to 5 with no stains.

(Example 1) Preparation of synthetic leather base-1> An impregnated base material was prepared by impregnating a nonwoven fabric made of polyester fibers with a weight of 280 g/end and a thickness of 1.01 with a 13% concentration polyester polyurethane-dimethylformamide solution. The surface was coated with a 18% polyester polyurethane-dimethylformamide solution with a basis weight of 600 g/-rIi, followed by water immersion coagulation, water washing, and drying to prepare synthetic leather substrate-1.

<Creation of paint-1> Paint-1 was prepared with the following composition.

Chrisbon NY 320 100 copies (
Haulak A 1104 White 30 parts (Dainippon Ink & Chemicals) 30 parts (Dainippon Ink & Chemicals) Hauluck A 1008 Mat 30 parts (Dainippon Ink & Chemicals) Isoprobil alcohol 50 parts Methyl Chilketone 40 parts N, N-dimethylformamide 10 parts <Preparation of paint-2> Polyamino acid urethane (using non-yellowing type urethane: (
Seiko Kasei ■) LLICKSKINU A-32
95A; N, N- of polyamino acid segment 35%)
70 parts of dimethylformamide solution (solid content 12%) and fluorine-modified polyurethane (non-yellowing type urethane used =
(Manufactured by Dainichiseika Kogyo ■) Retheroid LLJ-4110)
N,N-dimethylformamide:isopropyl alcohol:toluene (=1:1:1) solution (solid content 12%)
30 parts were mixed to create a mixed resin solution. In this,
Matting agent (manufactured by Dainippon Ink &Chemicals; Hauluck 81)
356) were added and mixed to obtain a mixed solution paint.

<Application on the surface of synthetic leather> Apply paint to the surface of the synthetic leather substrate-1 prepared above.
1 was applied and dried 3 times using a gravure coater (using a 110 mesh roll), and then patterned using a heated embossing roll.
The coating and drying process was repeated three times (using a mesh roll) to obtain synthetic leather with a white surface. The surface of the resulting synthetic leather is warm to the touch without feeling cold, and does not feel sticky even on sweaty skin, making it excellent for use in volleyball and handball. there were. It also has greater moisture permeability than conventional synthetic leather, making it an excellent upper material for sports shoes. Table 1 shows the characteristic values of the obtained synthetic leather.

(Example 2) <Creation of paint-3> Paint-3 was prepared with the following composition.

L U C K S K r N -U A 3295
A 80 parts (manufactured by Seiko Kasei ■) Rezeroid l IJ-411020 parts (manufactured by Dainichiseika Chemical Industry ■) Dailac S L -3440 Red 5 parts (
(manufactured by Dainippon Ink & Chemicals) 40 parts N,N-dimethylformamide 40 parts methyl ethyl ketone The coating and drying process was repeated three times using a heated embossing roll (using a roll), followed by patterning using a heated embossing roll to obtain synthetic leather having a red coating on the surface. The surface of the resulting synthetic leather is warm and does not feel cold when it comes in contact with the skin, and has a good feel without being sticky even on sweaty skin, making it an excellent material for basketballs and rugby balls. It was something. Table 1 shows the characteristic values of the obtained synthetic leather.

(Example 3) <Preparation and application of paint-4> Polyamino acid urethane (using non-yellowing type urethane;
(manufactured by Mitsubishi Kasei ■) PAU-300: 60 parts of N,N-dimethylformamide solution (solid content 15%) of polyamino acid segment (35%) and fluorine-modified polyurethane resin (
Letheroid 1jl-4770: (Dainippon Fine Chemical Industry ■
N,N-dimethylformamide:isopropyl alcohol:toluene (-1:1:1) solution (solid content 15
%) 7 parts of urea was dissolved in 40 parts of mixed resin solution while heating, and black pigment (manufactured by Dainippon Ink & Chemicals, Ltd.; Dailac S L-3430) was added as a coloring agent.
part, and black dye <Kayaset 8LACK- manufactured by Nippon Kayaku ■
3 parts of KR) were added and mixed uniformly to obtain a black paint. This black paint was applied to a patterned release paper to have a basis weight of 709/rIL, and after drying at 110°C, the adhesive was applied to a basis weight of 509/rd to create the same as in Example 1. It was laminated onto the surface of the synthetic leather substrate-1 and sufficiently adhered. The synthetic leather separated from the release paper was heated to 60 (10
) was washed with hot water to obtain black synthetic leather with a porous surface.

The surface of the resulting synthetic leather is warm and does not feel cold when it comes in contact with the skin, and has an excellent feel without feeling sticky even on sweaty skin. It was suitable for such things. Table 1 shows the characteristic values of the obtained synthetic leather.

(Example 4) <Creation of synthetic leather substrate-2> Polycarbonate polyurethane (manufactured by Dainichiseika Kogyo ■; Rezamin CU 945ON L) was applied to a nonwoven fabric made of polyester fibers with a weight of 280 g/end and a thickness of 1.0 m/W.
) and polyamino acid urethane (P A U-300) (mixing ratio = 60:40).
A U -300) f7) 1 polymer (mixing ratio = 6
0:40) f7) N,N-dimethylformamide solution (
Synthetic leather substrate-2
It was created.

Preparation of paint-5〉 Polyamino acid urethane (using non-yellowing type urethane: (
Seiko Kasei@) LUCKSK I NuA-32
95A) in N,N-dimethylformamide solution (solid content 10%) and 60 parts of N,N-dimethylformamide solution (solid content 10%) and N,N-
In a mixed resin solution of 40 parts of dimethylformamide:isopropyl alcohol:toluene (=1:1:1) solution (solid content 10%), 5 parts of urea was dissolved while heating.
Further, 2 parts of a white pigment (manufactured by Dainippon Ink & Chemicals Co., Ltd., Dailac SL-3410) was added as a coloring agent and mixed uniformly to obtain a white paint.

Application to the surface of synthetic leather> The paint prepared in Example 1 was applied to the surface of the synthetic leather substrate-2.
Coating and drying was repeated three times using a gravure coating machine (using a 110 mesh roll), and then patterned with a heated embossing roll, and then coating 5 was applied using a gravure coating machine (using a 110 mesh roll). -Drying was repeated three times. Then, it was immersed in 80 (10) warm water for 5 minutes and dried. The surface of the obtained synthetic fiber not only had an excellent surface feel as in Example 1, but also had excellent moisture permeability, moisture absorption, and moisture release properties, and was used as an upper material for sports shoes. In this case, it was excellent and did not feel stuffy when worn. This is because the surface is porous and has high air permeability, but the reason for this high air permeability is that the organic solvent of Paint-5 is non-porous during application and drying of Paint-5. Dissolving and destroying the coating film obtained from paint-1,
This is thought to be because the film itself forms a porous film, making the entire film slow-porous. Table 1 shows the characteristic values of the obtained synthetic leather.

(Example 5) <Creation of synthetic leather base-3> Polycarbonate urethane (Dainichiseika Co., Ltd. Made by Kogyo: Rezamin CU 945ON L> Impregnated with a mixed polymer of N,N-dimethylformamide solution (concentration 10%) and polyamino acid urethane (PAU-300) (mixing ratio = 60:40) on the surface of the base material,
Non-yellowing polycarbonate polyurethane (manufactured by Dainichiseika Kogyo ■; Rezamin CNU330) and polyamino acid urethane (using non-yellowing type urethane: manufactured by Seiko Kasei ■; LU
600! [IF, 7IQ basis weight]], water immersion coagulation, water washing, and drying were performed to prepare a synthetic leather substrate-3.

<Application on the synthetic leather surface> The surface of the synthetic leather substrate-3 was patterned using a heated embossing roll, and then the paint 5 prepared in Example 4 was applied and dried using a gravure coating machine (using a roll of 110 mesh). 3
After repeating this process several times, it was immersed in 80 (10) warm water for 5 minutes and dried to obtain synthetic leather with a white surface. The surface of the obtained synthetic leather not only had an excellent surface feel, but also had excellent moisture permeability, moisture absorption, moisture release, and air permeability, and did not feel stuffy when worn. Generally, breathable products that have a porous membrane are easily discolored by nitrogen oxide gas, but this product uses non-yellowing polyurethane from the surface to the four porous layers on a synthetic leather base. Therefore, there was no discoloration due to nitrogen oxide gas. Table 1 shows the characteristic values of the obtained synthetic leather.

<Example 6) Paint-5 prepared in Example 4 was applied to the surface of nylon taffeta to a basis weight of 70 g/m and dried.
It was immersed in 0 (10) warm water for 5 minutes and dried. The obtained product had high moisture permeability and was comfortable to the touch, making it ideal for sports clothing.

Table 1 shows the characteristic values of the obtained synthetic leather.

(Comparative example 1) <Creation of paint-6> Paint-6 was prepared with the following composition.

Hauluck A 3454 (20%) 100 parts (manufactured by Dainippon Ink and Chemicals) Hauluck △ 1008 Matsut 30 parts (
(manufactured by Dainippon Ink & Chemicals) 50 parts of isopropyl alcohol 50 parts of methyl ethyl ketone <Application on the surface of synthetic leather> Apply paint-1 to the surface of synthetic leather substrate-1 prepared in Example 1 using a gravure roll (110 mesh). - After repeating the drying process three times, a pattern is attached using a hot embossing roll, and then paint-6 is applied to the surface using a gravure roll (110
The coating and drying process was repeated three times using a mesh cloth to obtain synthetic leather with a white surface. The resulting synthetic leather had poor moisture permeability, water absorption, and moisture release properties, and the surface feel was that of conventional polyurethane synthetic leather. The characteristic values of the obtained synthetic leather are also shown in Table 1.

(Comparative example 2) Paint-7 was created with the following composition.

LUCKSK I N-UA 3295 A (18
%) 100 parts (manufactured by Seiko Chemicals) Hauluck 3 1356 Mat 20 parts (manufactured by Dainippon Ink & Chemicals) N,N-dimethylformamide 40 parts Methyl ethyl ketone 40 parts <Application on the surface of synthetic leather> Apply paint-1 to a gravure roll After repeating coating and drying three times on the surface of the synthetic leather substrate 1 prepared in Example 1 using a 110 mesh machine, a pattern was applied using a heated embossing roll, and then paint 7 was applied on the surface using a gravure roll. (110
The coating and drying process was repeated three times using a mesh cloth to obtain synthetic leather with a white surface. The resulting synthetic leather had a slightly sticky surface feel and was easily stained. The characteristic values of the obtained synthetic leather are also shown in Table 1.

Table 1 The sticky feeling evaluation on sweaty skin in the above table is based on the following.

◎ No stickiness, very good ○ No stickiness, good △ Slight stickiness, but good Amino acid urethane (using non-yellowing type urethane: (manufactured by Seiko Kasei @I) LUC
KSK I N-uA-3295A; Polyamino acid segment 35%) N,N-dimethylformamide solution (solid content 12%) 70 parts and fluorine-modified polyurethane (non-yellowing type urethane used: (Dainichiseika Kogyo ■1fA)
N,N dimethylformamide: isopropyl alcohol: toluene (-1:
1:1) solution (solid content: 12%) were mixed to prepare a mixed resin solution. In this, synthetic polyamic acid particles (
Manufactured by Ajinomoto ■; Azikoat PA-1000; Poly-γ
- Glutamate: average particle size 10 μm) 5 parts, and a matting agent (manufactured by Dainippon Ink & Chemicals ■; Howlac B1356)
) 15 parts were added and mixed to obtain a mixed solution paint.

<Application on the surface of synthetic leather> Apply paint to the surface of the synthetic leather substrate-1 prepared above.
1 was coated and dried three times using a gravure coater (using a 110 mesh roll), and then patterned using a heated embossing roll, and then coated with gravure paint 2! 1I (
The coating and drying process was repeated three times using a roll of 110 mesh (using a roll of 110 mesh) to obtain synthetic leather with a white surface. The surface of the resulting synthetic leather is warm to the touch without feeling cold, and does not feel sticky even on sweaty skin, making it excellent for use in volleyball and handball. there were. It also has greater moisture permeability than conventional synthetic leather, making it an excellent upper material for sports shoes. The characteristic values of the obtained synthetic leather are
It is also shown in the table.

(Example 8) <Creation of paint-8> Paint-8 was prepared with the following composition.

LUCKSK I N-UA 3295 A
80 parts (manufactured by Seiko Kasei ■) Rezeroid LU-411020 parts (manufactured by Dainichi Seikagaku Kogyo ■) Azikote P A -100010 parts (manufactured by Ajinomoto ■: average particle size near μm) Dilac S L -3440 Red 20 parts (Dainippon Ink Chemical industry ■18I) N,N-dimethylformamide 40 parts Methyl ethyl ketone 40 parts <Application on the surface of synthetic leather> Paint-8 was applied gravure to the surface of the synthetic leather substrate 1 prepared in Example 1 l1 (using a roll of 110 mesh) )in,
The coating and drying process was repeated three times and then patterned using a heated embossing roll to obtain synthetic leather having four red glands on the surface.

The surface of the resulting synthetic leather is warm and does not feel cold when it comes in contact with the skin, and has a good feel without being sticky even on sweaty skin, making it an excellent material for basketballs and rugby balls. It was something. Table 2 shows the characteristic values of the obtained synthetic leather.

(Example 9) <Preparation and application of paint-9> Polyamino acid urethane (using non-yellowing type urethane:
60 parts of N,N-dimethylformamide solution (solid content 15%) of PAU-300 (manufactured by Mitsubishi Kasei ■): 35% polyamino segment) and 60 parts of a fluorine-modified polyurethane resin (Resaloid l-C 4110: (manufactured by Nippon Fine Chemical Industry ■) N,N-dimethylformamide: isopropyl alcohol °toluene (-1 to 1) solution (solid content 15%) 40
5 parts of synthetic polyamino acid particles (manufactured by Ajinomoto ■, Azikoat PA-1000: poly-γ-methyl-L-glutamate; average particle size: 10 μm) were added to the mixed resin solution of 1 part, uniformly dispersed, and mixed. A dispersion was obtained. In this, urea 7
The mixture was dissolved while heating, and a black pigment (manufactured by Dainippon Ink and Chemicals Co., Ltd.: Dairakku S L-34) was added as a coloring agent.
30> 8 parts, and black dye <Kayaset B manufactured by Nippon Herbal Medicines
3 parts of LACK-KR) were added and mixed uniformly to obtain a black paint. This black paint was applied to a patterned release paper to give a basis weight of 707/bottom, and after drying at 110°C, the adhesive was applied to a basis weight of 50 g/bottom to create the same product as in Example 1. It was laminated onto the surface of the synthetic leather substrate-1 and sufficiently adhered.

The synthetic leather separated from the release paper was washed with 60 (10) warm water to obtain black synthetic leather with a porous membrane on the surface.

The surface of the resulting synthetic leather is warm and does not feel cold when it comes in contact with the skin, and is non-sticky and has an excellent feel even on sweaty skin. It was suitable for the back. Table 2 shows the characteristic values of the obtained synthetic leather.

(Example 10) <Preparation of paint-10> Polyamino acid urethane (using non-yellowing type urethane:
(Manufactured by Seiko Kasei ■) LUCKSKINuA-329
5A) of N,N-dimethylformamide solution (solid content 10%) and 60 parts of fluorine-modified polyurethane resin (Retheroid 1JL-4110: (manufactured by Inu Nippon Seika Kogyo)).
, N-dimethylformamide; isopropyl alcohol:toluene (-1:1:1) solution (solid content 10%) 40
5 parts of synthetic polyamino acid particles (manufactured by Ajinomoto ■: Azikoat PA-1000; poly-γ-methyl-thi-glutamate: average particle size: 10 μm) were added to the mixed resin solution of 1 part, uniformly dispersed, and mixed. A dispersion was obtained. In this, 5 parts of urea was dissolved while heating, and a white pigment (manufactured by Dainippon Ink Seigaku Kogyo ■; Dailac 5l-3) was added as a coloring agent.
410) were added and mixed uniformly to obtain a white paint.

<Application on the surface of synthetic leather> The paint prepared in Example 1 was applied to the surface of the synthetic leather substrate-2.
Coating 1 with a gravure coating machine (using a roll of 110 mesh), repeating coating and drying three times, then patterning with a heated embossing roll, and then applying paint 10 with gravure coating 1 (i+o
The coating and drying process was repeated three times using a mesh roll. Then, it was immersed in 80 (10) warm water for 5 minutes and dried. The surface of the obtained synthetic fiber not only has an excellent surface feel as in Example 7, but also has even better moisture permeability, moisture absorption, and moisture release properties, and when used as an upper material for sports shoes. It was excellent and did not feel stuffy when worn. This is because the surface is porous and has high air permeability, but the reason for this high air permeability is that the organic solvent of Paint-5 is non-porous during application and drying of Paint-5. This is thought to be because the coating film obtained from Paint-1 was dissolved and destroyed and a porous film was formed by itself, so that the entire film had continuous pores. Table 2 shows the characteristic values of the obtained synthetic leather.

(Example 11) <Creation of synthetic leather base-4> Weight 280=j/lri, thickness 1. A mixture of polycarbonate urethane (manufactured by Dainichiseika Kogyo ■; Rezamin CU 945ON L) and polyamino acid urethane (PA U-300) in a nonwoven fabric made of Omm polyester fiber and rayon m miscellaneous (mixing ratio: 30 near 0). A mixed dispersion liquid in which 8 parts of synthetic polyamino acid particles (manufactured by Ajinomoto ■; Azikoat PA-1000) were dispersed in an N,N-dimethylformamide solution (concentration 10%) with a polymer mixing ratio of -60:40. The surface of the impregnated base material is impregnated with non-yellowing polycarbonate polyurethane (manufactured by Dainichiseika Chemical Industry Co., Ltd.; Rezamin CNU330) and polyamino acid urethane (using non-yellowing type urethane; made by Seiko Kasei Co., Ltd.: LUCKSK).
IN-UA3295A) mixed polymer (mixing ratio -60
:40) in N,N-dimethylformamide (concentration 1
A mixed dispersion in which 10 parts of synthetic polyamino acid particles (manufactured by Ajinomoto ■: Azikoat PA-1000) were dispersed was coated with a basis weight of 6001/l (8%), followed by water immersion coagulation, water washing, and drying. A synthetic leather substrate-4 was prepared in this manner.

<Application on the synthetic leather surface> The surface of the synthetic leather substrate 4 was patterned with a heated embossing roll, and then the paint 10 prepared in Example 10 was applied with a gravure coating machine (using a roll of 110 mesh). After repeating drying three times, it was immersed in 80 (10) warm water for 5 minutes and dried to obtain synthetic leather with a white surface. The surface of the obtained synthetic leather not only has an excellent surface feel, but also has excellent moisture permeability, moisture absorption, moisture release, and air permeability, making it an excellent material that does not feel stuffy when worn as an upper material for sports shoes. It was something like that. Generally, products with a porous membrane and breathability are easily discolored by nitrogen oxide gas, but this product uses non-yellowing polyurethane from the surface to the porous coating on a synthetic leather base. For,
There was no discoloration due to nitrogen oxide gas. The characteristic values of the obtained synthetic leather are shown in Table 2.

(Example 12) Paint-1 prepared in Example 10 on the surface of nylon taffeta
0 to a basis weight of 70ti/rd and dry it.
Then, it was immersed in 80 (10) warm water for 5 minutes and dried. The resulting product has high moisture permeability and feels good on the skin.
It was perfect for sports clothing.

Table 2 shows the characteristic values of the obtained synthetic leather.

Table 2 (Example 13) Preparation of paint-11> Polyamino acid urethane (
Uses non-yellowing type urethane: (manufactured by Seiko Kasei) LU
CKSK I N-u△-3295A: 10 parts of N,N~dimethylformamide solution (solid content 12%) of polyamino acid segment (35%) and fluorine-modified polyurethane (
Uses non-yellowing type urethane = (manufactured by Dainichiseika Kogyo ■) Rezaroid L U-4110>N.

N-dimethylformamide: Isopropyl alcohol:
Toluene (-1:1:1) solution! 2 (solid content 12%) 3
0 parts were mixed to create a mixed resin solution. In this, 5 parts of particles made of natural collagen that does not contain chromium (manufactured by Showa Denko ■; CX-260 + average particle size near μm) and a matting agent (manufactured by Dainippon Ink & Chemicals ■: Howlac 313) are added.
56) 15 parts were added and mixed to obtain a mixed solution paint.

<Application on the surface of synthetic leather> Apply paint to the surface of the synthetic leather substrate-1 prepared above.
Coating and drying was repeated three times using a gravure coater (using a roll with a 110 mesh), and then patterned with a heated embossing roll, after which paint 2 was applied using a gravure coater (using a D-roll with a 110 mesh). , repeat coating and drying three times,
A synthetic leather with a white surface was obtained. The surface of the resulting synthetic leather is warm to the touch without feeling cold, and does not feel sticky even on sweaty skin, making it excellent for use in volleyball and handball. there were. It also has greater moisture permeability than conventional synthetic leather, making it an excellent upper material for sports shoes. Table 3 shows the characteristic values of the obtained synthetic leather.

(Example 14) Creation of paint-12> Paint-3 was prepared with the following composition.

LUCKSmlN-UA 3295A 8
0 parts (manufactured by Seiko Kasei ■) Retheroid L U -411020 parts (manufactured by Dainichi Seikagaku Kogyo ■) Natural collagen particles CX -26010 parts (manufactured by Showa Denko ■) Dilac S L-3440 Red 5 parts (manufactured by Dainippon Ink & Chemicals ■) 40 parts of N,N-dimethylformamide 40 parts of methyl ethyl ketone <Application on the surface of synthetic leather> Paint-12 was applied to the surface of the synthetic leather substrate 1 prepared in Example 1 using a gravure coating machine (using a roll of 110 mesh).
The coating and drying process was repeated three times and then patterned using a heated embossing roll to obtain synthetic leather having a red coating on the surface.

The surface of the resulting synthetic leather is warm and does not feel cold when it comes in contact with the skin, and has a good feel without being sticky even on sweaty skin, making it an excellent material for basketballs and rugby balls. It was something. Table 3 shows the characteristic values of the obtained synthetic leather.

(Example 15) <Preparation and application of paint-13> Polyamino acid urethane (I yellowing type urethane used: (
PAU-300 (manufactured by Mitsubishi Kasei ■): 60 parts of a N,N-dimethylformamide solution (solid content 15%) of polyamino gt (35%) and fluorine-modified polyurethane resin (
Letheroid 1jJ-4NO: (Nippon Fine Chemical Industry ■
Particles made of natural collagen (manufactured by Showa Denko :CX-260: average particle size near μm) was added and uniformly dispersed to obtain a mixed dispersion. Into this, 7 parts of urea was dissolved while heating, and further 8 parts of black pigment (manufactured by Dainippon Ink & Chemicals, Ltd.: Dailac 5L-3430) as a coloring agent, and black dye (Kayaset B180, manufactured by Nippon Herbal Chemicals, Ltd.) were added. -KR) was added and mixed homogeneously to obtain a black paint. This black paint was applied to a patterned release paper to have a basis weight of 709/m, and after drying at 110°C, the adhesive was applied to a basis weight of 509/m to create the same product as in Example 1. It was laminated onto the surface of the synthetic leather substrate-1 and sufficiently adhered. The synthetic leather separated from the release paper was washed with 60 (10) warm water to obtain black synthetic leather with a porous membrane on the surface.

The surface of the resulting synthetic leather is warm and does not feel cold when it comes in contact with the skin, and has an excellent feel without becoming sticky even when sweaty. It was suitable for the back. Table 3 shows the characteristic values of the obtained synthetic leather.

(Example 16) Preparation of paint-14> Polyamino acid urethane (using non-yellowing type urethane:
(Manufactured by Seiko Kasei ■) LUCKSK I NuA-3
60 parts of N,N-dimethylformamide solution (solid content 10%) of 295A) and N,N-dimethylformamide of fluorine-modified polyurethane resin (Retheroid LU-4110 (manufactured by Dainippon Seika Kogyo): isopropyl alcohol: Toluene (=1:1:1) solution (solid content 10%) 4
Particles made of natural collagen (manufactured by Showa Denko ■; CX-260: average particle size near μT) were added to 0 parts of mixed resin solution.
rL) was added and uniformly dispersed to obtain a mixed dispersion. Into this, 5 parts of urea was dissolved while heating, and 2 parts of a white pigment (manufactured by Dainippon Ink & Chemicals Co., Ltd.; Dailac 5L-3410) as a coloring agent was added and mixed uniformly to obtain a white paint.

<Application on the synthetic leather surface> The coating Il prepared in Example 1 was applied to the surface of the synthetic leather substrate-2.
Gravure coating 1fi (using 110 mesh roll)
After repeating coating and drying three times, and then applying a pattern using a heated embossing roll, paint 14 was applied to gravure coating 1 (11
The coating and drying process was repeated three times using a roll of 0 mesh. Then, it was immersed in 80 (10) warm water for 5 minutes and dried. The surface of the obtained synthetic fiber not only has an excellent surface feel as in Example 13, but also has even better moisture permeability, moisture absorption, and moisture release properties, and when used as an upper material for sports shoes. It was excellent and did not feel stuffy when worn. This is because the surface is porous and has high air permeability, but the reason for this high air permeability is that when Paint-14 is applied and dried, the organic solvent of Paint-14 is non-porous. It is thought that this is because the coating film obtained from a certain paint-1 is dissolved and destroyed, and a porous film is formed by itself, so that the entire film has continuous pores. Table 3 shows the characteristic values of the obtained synthetic leather.

(Example 17) <Creation of synthetic leather base-5> Polycarbonate-based urethane (Dainichiseika Made by Kogyo: Natural collagen in an N,N-dimethylformamide solution (concentration 10%) with a mixed polymer of Rezamin CU 945ON L) and polyamino acid urethane (PAU-300) (mixing ratio -60:40) Particles (manufactured by Showa Denko ■; CX-260: average particle size 7 μm) 8
Non-yellowing polycarbonate polyurethane (manufactured by Dainichiseika Kogyo ■: Rezamin CNU330) and polyamino acid urethane (non-yellowing type urethane used: t) -1'D, -chemical ■
Particles made of natural collagen (manufactured by Showa Denko ■: CX260; average particle diameter 7μm)
After coating a mixed dispersion in which 10 parts of 10 parts were dispersed at a basis weight of 600 g/IIIq, the mixture was coagulated by water immersion, washed with water, and dried to prepare a synthetic leather substrate-5.

<Application on the surface of synthetic leather> A pattern was applied to the surface of the synthetic leather substrate-5 using a heated embossing roll, and then the paint 14 prepared in Example 16 was applied and dried using a gravure coating machine (using a roll of 110 mesh). After repeating this three times, it was immersed in 80 (10) warm water for 5 minutes and dried to obtain synthetic leather with a white surface. The surface of the obtained synthetic leather not only has an excellent surface feel, but also has even better moisture permeability, moisture resistance, and moisture release.
It was an excellent material that did not feel stuffy when worn as an upper material for sports shoes. Generally, products with a porous membrane and breathability are easily discolored by nitrogen oxide gas, but this product uses non-yellowing polyurethane from the surface to the porous coating on a synthetic leather base. Therefore, there was no discoloration due to nitrogen oxide gas. Table 3 shows the characteristic values of the obtained synthetic leather.

(Example 18) Paint-1 prepared in Example 16 on the surface of nylon taffeta
No. 4 was applied to give a basis weight of 70'J/rrt and dried, and then immersed in warm water of No. 80 (10) for 5 minutes to dry. The obtained product had high moisture permeability and was comfortable to the touch, making it ideal for sports clothing.

Table 3 shows the characteristic values of the obtained synthetic leather.

Claims (13)

[Claims] (1) Synthesis characterized by forming a coating of a mixed resin mainly composed of polyamino acid urethane resin and fluorine-modified polyurethane resin on the surface of a synthetic leather base made of fibers or fibers and synthetic resin. leather. (2) The synthetic leather according to claim 1, wherein the coating of a mixed resin whose main components are a polyamino acid urethane resin and a fluorine-modified polyurethane resin is continuous and porous. (3) A claim in which the polyamino acid urethane resin is a polyamino acid segment whose main component is poly-γ-methyl-L-glutamate, and the content thereof is 3% to 85% by weight based on the polyamino acid urethane resin. (1) or the synthetic leather of claim (2). (4) A coating of a mixed resin mainly composed of polyamino acid urethane resin, fluorine-modified polyurethane resin, and synthetic polyamino acid particles was formed on the surface of a synthetic leather substrate made of fibrous material or fibrous material and synthetic leather. Synthetic leather is characterized by: (5) The synthetic leather according to claim (4), wherein the coating of a mixed resin mainly composed of a polyamino acid urethane resin, a fluorine-modified polyurethane resin, and synthetic polyamino acid particles is continuous and porous. (6) A claim in which the polyamino acid urethane resin is a polyamino acid segment whose main component is poly-γ-methyl-L-glutamate, and the content thereof is 3% to 85% by weight based on the polyamino acid urethane resin. (4) or the synthetic leather of claim (5). (7) Synthetic polyamino acid particles are poly-γ-methyl-L
- The synthetic leather according to any one of claims (4) to (6), which is glutamate. (8) The synthetic leather according to any one of claims (4) to (7), wherein the synthetic resin constituting the synthetic leather base is a synthetic resin mainly composed of a polyamino acid urethane resin and synthetic polyamino acid particles. (9) Forming a coating of a mixed resin mainly composed of particles made of polyamino acid urethane resin, fluorine-modified polyurethane resin, and natural collagen on the surface of a synthetic leather substrate made of fibrous material or fibrous material and synthetic resin. Synthetic leather is characterized by: (10) Claim (9) wherein the coating of a mixed resin whose main components are particles of polyamino acid urethane resin, fluorine-modified polyurethane resin, and natural collagen is continuous and porous.
synthetic leather. (11) A claim in which the polyamino acid urethane resin is a polyamino acid segment whose main component is poly-γ-methyl-L-glutamate, and the content thereof is 3% to 85% by weight based on the polyamino acid urethane resin. (9) or the synthetic leather of claim (10). (12) According to any one of claims (9) to (11), the particles made of natural collagen are purified by biochemical treatment from animal skin, etc., and are heat-chemically crosslinked particles. Some synthetic leather. (13) Claim (
Synthetic leather as defined in any one of 9) to (12).