JPH02234981A - Production of flexible leather-like sheet material - Google Patents

Abstract

PURPOSE:To obtain the subject sheet by combining a step to form a fiber sheet composed of three-dimensionally interlocked multicompnent fibers capable of forming ultrafine fibers, a step to treat said fiber sheet with a specific compound and dry the sheet to a specific shrinkage, a step to form a grain face and a step to finely divide the fiber into ultrafine fibers. CONSTITUTION:For example, a fiber sheet is produced by three-dimensionally interlocking fibers capable of forming ultrafine polyamide fibers. The sheet is made to contact with a high-speed fluid flow (preferably water) to effect the division of the fiber into ultrafine fibers and/or the interlocking of the fibers to form a dense structure. As necessary, the treated sheet is allowed to shrink in hot water to increase the density and pressed to smoothen the surface. A polyurethane elastomer is applied to the surface to form a grain layer and the surface is treated with an emulsion of an aromatic alcohol and dried. Finally, the sheet is allowed to shrink at an areal shrinkage S1 (defined by formula) of as high as >=5 to obtain the objective soft leather-like sheet. The sheet has high stiffness, dense texture and excellent damage resistance of the grain face.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for manufacturing a flexible leather-like sheet material.

More specifically, it has a silver surface with excellent scratch resistance and a smooth touch, has a firm, dense, full feeling, and supple texture, and is resistant to changes in appearance such as shrinkage and grain loss due to washing. The present invention relates to a method for producing a flexible leather-like sheet material having a property of having very little and very good dimensional stability.

[Prior art] Conventionally, as a method for manufacturing a flexible leather-like sheet material having a grain layer, a nonwoven fabric or a knitted/woven fabric made of ultrafine fibers, or a fiber aggregate made of a composite of a nonwoven fabric and a knitted/woven fabric is used. , A method of forming a silver surface by laminating and integrating porous and non-porous or non-porous layers made of resin such as polyurethane on a porous sheet coated with an elastic polymer such as polyurethane. It has been known.

However, the leather-like sheet material obtained by such a method is
It had a strong rubber-like rebound feeling due to the elastic properties of polyurethane, and lacked a sense of unity, and was far from a flexible leather-like sheet material.

For this reason, various efforts have been made to eliminate the rubber-like rebound feeling and obtain a leather-like sheet material with a sense of unity.

That is, for example, two surface non-porous layers mainly made of an elastic polymer are laminated on a nonwoven fabric made of entangled fiber bundles made of fine fibers, on a base material containing a resin mainly made of an elastic polymer. A method of finishing the outermost surface with a leather-like appearance (Japanese Patent Laid-Open No. 134274/1983) has been proposed.

However, the products obtained by this method have an excellent sense of fulfillment and have improved creases and appearance quality, making them suitable for applications such as shoes and bags. It had a rubber-like rebound feel, and the texture was still hard.

In addition, a method has been proposed in which a non-porous polymer coating layer is formed on the surface of an intertwined body of a melt-blown web impregnated with a polymer elastic material (Japanese Unexamined Patent Publication No. 13785/1985), and method q. The sheet material obtained by this method is highly flexible and has a luxurious feel, but it still has a rubbery feel from the resin used for the silver surface, lacks a sense of unity, and also has a fluffy surface that makes the surface look like a silver surface. Because of this, it was inferior in kneading resistance and shear fatigue resistance.

On the other hand, in order to improve the above-mentioned problems, a composite body mainly composed of a urethane polymer and an intertwined fiber body in which the distance between fiber entanglement points of ultrafine fibers and/or bundles thereof is 200 microns or less is used. A method for producing a flexible leather-like sheet material having a grain layer was disclosed in Japanese Patent Application Laid-Open No. 1986-1975.
This is proposed in Publication No. 690. The products obtained by this method have a very supple texture and touch, and are also excellent in durability such as resistance to rubbing and shear fatigue, and are particularly useful as flexible leather-like sheets with a grain layer. It was excellent for use in clothing.

However, even if obtained by such a method,
For products that require particular flexibility, binders mainly composed of urethane polymers for the purpose of fixing fiber entanglement points are not used, or are used only in such amounts that it is recognized that they are not used in practice. There was a problem with dimensional stability after washing. That is, since the fiber entanglement points in the fiber entangled body are not substantially fixed with the urethane polymer, there is a drawback that the dimensions after washing shrink beyond the practically acceptable shrinkage range (generally within about 3%). Furthermore, there was also the drawback that the fine grain pattern, similar to natural leather, provided on the surface of the grain layer became unclear. These drawbacks can be solved by using an appropriate amount of binder and substantially fixing the intertwined points of the fibers with urethane polymer, but on the other hand, there is the problem that the texture must be sacrificed, and in recent years In order to meet diversifying consumer tastes and to meet the needs of fashion materials, it is especially desirable to solve the above drawbacks while maintaining a good texture. Ta.

On the other hand, Japanese Patent Publication No. 53-35633 proposes a method of imparting silk-like texture and luster to polyamide knitted fabrics using benzyl alcohol or phenylethyl alcohol. However, in this method, a knitted fabric originally composed of fibrillable filaments is treated with the above-mentioned alcohol to simply fibrillate it to obtain a silk-like texture and luster. What is the purpose of manufacturing a flexible leather-like sheet material that has a silver surface, has a firm, dense, full feeling, and supple texture, and is also easy to wash? They are fundamentally different.

[Problems to be Solved by the Invention] The present inventors have fully taken these problems into consideration, and have developed a material that does not have the above-mentioned problems, has excellent scratch resistance such as rubbing resistance and shear fatigue resistance, and is extremely smooth. Equipped with a silver surface with a touch of
A flexible leather-like material that is firm, dense, full-bodied, and has a supple texture.Furthermore, it has excellent dimensional stability with almost no changes in appearance such as shrinkage or grain loss due to washing. They conducted extensive research to find a method for manufacturing sheet products, and finally arrived at the present invention.

[Means for Solving the Problems] That is, the method for producing a flexible leather-like sheet product of the present invention is characterized in that the method for producing a flexible leather-like sheet product is characterized by combining at least the following steps (1) to (2) or (2) to (3) below. This is a method for producing similar sheet products.

(2) A process for obtaining a fibrous sheet having a three-dimensional entanglement of ultrafine polyamide fibers or ultrafine fiber-forming multicomponent fibers that generate ultrafine polyamide fibers through mechanical manipulation or chemical treatment.

(2) Treating the fibrous sheet obtained in the above step (2) with an emulsion of aromatic alcohol and drying it to obtain a fibrous sheet whose shrinkage due to the treatment is 5 or more in area shrinkage Sa expressed by the following formula I. .

Sa = (So S1)/So XIOO −”
・1 However, Sa: area shrinkage rate (%) S due to the treatment
o: Area before the treatment SI: Area after the treatment ■ A step of applying a urethane polymer to at least one side of the fibrous sheet to make it grainy.

(2) When ultrafine fiber-forming multicomponent fibers are used in step (2), a step of forming ultrafine fibers from the ultrafine fiber-forming multicomponent fibers.

[Function] In the method for producing a flexible leather-like sheet product of the present invention, the fiber layer is made of polyamide ultrafine fibers and/or bundles thereof, and the grain layer is made of polyamide ultrafine fibers and/or bundles thereof. The basic idea is to treat a fibrous sheet, which is a composite material made of urethane polymer, with an emulsion of aromatic alcohol and dry it to make it highly shrinkable.The combination of these two methods is the first to achieve resistance to rubbing and shearing. It has excellent scratch resistance such as fatigue resistance, and has a silver surface with an extremely smooth touch.
We provide a flexible leather-like sheet material that has a firm, dense, full-bodied feel, and supple texture, and has excellent dimensional stability with almost no changes in appearance such as shrinkage or grain loss due to washing. It became possible to do so.

A feature of the present invention is that a fibrous sheet is treated with an emulsion of aromatic alcohol, dried and shrunk, and the fibrous sheet as described above is made into a highly dense sheet by this treatment. .

Hereinafter, the method for producing a flexible leather-like sheet material of the present invention will be explained in more detail.

The ultrafine polyamide fibers used in the present invention may be those produced directly by methods such as super draw or melt blowing, but if the fibers become too thin, spinning becomes unstable, and processing is difficult and difficult to handle. For this reason, it is preferable to use the ultrafine fiber-forming multicomponent fiber described below and to modify it into polyamide ultrafine fiber at an appropriate point during the processing process.

That is, the ultrafine fiber-forming multicomponent fiber that can be used in the present invention is, for example, a fiber made by converging ultrafine fibers immediately after spinning and lightly adhering them into a single fiber, or a fiber in which one component is formed radially between other components. Fibers with a chrysanthemum-shaped cross section interposed between fibers, multilayer bimetal fibers, multilayer bimetal fibers with a donut-shaped cross section, sea-island mixed spun fibers made by melt-mixing two or more components, or spun fibers in the fiber axis direction. Polymer mutual array fibers, etc., in which a large number of continuous ultrafine fibers are arranged and aggregated and combined and/or partially combined with other components to form a single fiber, and two or more types of these fibers are mixed or combined. It may also be used. Further, an ultrafine fiber-forming multicomponent fiber made of multiple components that yields a bundle of fibers mainly consisting of ultrafine fibers of 0.2 denier or less, preferably 0.05 denier or less, when at least one component is dissolved and removed, It is particularly preferably used because it yields a supple and flexible leather-like sheet material with a particularly smooth surface.

Further, examples of the polyamide ultrafine fibers in the present invention include nylon 4, nylon 6, nylon 7, nylon 11, nylon 12, nylon 66, nylon 610, and copolymerized nylon.

In addition, examples of the bonding component or the dissolving and removing component of the ultrafine fiber-forming multicomponent fiber include polystyrene, polyethylene, polypropylene, polyamide, polyurethane, copolymerized polyethylene terephthalate easily soluble in alkaline solutions, polyvinyl alcohol, and polyvinyl alcohol. Polymerized polyvinyl alcohol, styrene-acrylonitrile copolymer, higher alcohol ester of styrene and acrylic acid, and/or
Alternatively, a copolymer of methacrylic acid with a higher alcohol ester may be used. In particular, ease of spinning,
From the viewpoint of ease of dissolution and removal, polystyrene, styrene-acrylic nitrile copolymers, and copolymers of styrene and higher alcohol esters of acrylic acid and/or higher alcohol esters of methacrylic acid are preferably used. Furthermore, a copolymer of styrene and a higher alcohol ester of acrylic acid and/or a higher alcohol ester of methacrylic acid is more preferably used, since a high stretching ratio can be obtained and a fiber with high strength can be obtained. Further, in order to make the ultrafine fibers more likely to branch, it is preferable to use a mixture of 0.5 to 30% by weight of a polymer such as polyethylene glycol in the binding component or the dissolving and removing component.

The fineness of such microfiber-forming multicomponent fibers is not particularly limited, but is preferably 1 to 10 deniers from the viewpoint of stability during spinning and ease of sheet formation.

In the present invention, the ultrafine polyamide fibers constituting the grain layer preferably have a fineness of 0.2 denier or less. 0.
If it is thicker than 2 deniers, the fibers are highly rigid and the flexibility of the grain layer and the wrinkle form on the surface are likely to be impaired, and cracks are likely to occur due to rubbing, etc., and unevenness may occur on the surface. It is generally difficult to form a smooth grain surface layer, and it is less than 0.2 denier, preferably 0.05 denier.
By using ultrafine fibers with a denier or less, the fibers can be improved. When the silver surface is formed as a composite with the urethane polymer described later, it has good smoothness and flexibility, is less prone to cracking, and has a smooth touch. A flexible leather-like sheet material is obtained.

In the method for producing a flexible leather-like sheet material of the present invention, it is preferable that the fiber structure in the grain layer is such that ultrafine fibers and/or bundles thereof are densely intertwined with each other. In other words, the fiber entanglement density is high. One method for measuring the intertwining density of fibers is to measure the distance between fiber intersection end points, which will be described later.In the present invention, the fibers in the grain layer have an intertwining density of 200 microns or less as measured by this method. It is better to use what you have. This value is 20
Those with a structure larger than 0 micron, for example, those with a fiber structure with little entanglement in which the fibers are entangled only by needle punching, such as the value is generally around 500 microns, or the structure where ultrafine fibers or bundles thereof are simply arranged in a plane. Also, those with a structure in which ultrafine fibers or bundles thereof are densely grown in a fluff-like manner on the surface of the base material and laid down to create a surface, there is little or no entanglement of fibers, so it cannot be rubbed, kneaded, or repeatedly sheared. This tends to be undesirable because the surface tends to fluff or crack when subjected to force. In order to eliminate these drawbacks, it is desirable that the distance between fiber entanglement points is 200 microns or less, and 100 microns or less.
When the size is less than a micron, more preferable concretions can be obtained.

Here, the distance between fiber entanglement points is JP-A-60-17569.
This is determined by the method disclosed in Publication No. 0.

In the production of the flexible leather-like sheet material of the present invention, a single structure of nonwoven fabric or a laminated structure of nonwoven fabrics can be used.
Although not particularly limited, it is desirable to have a single structure of nonwoven fabric in order to obtain uniform shrinkage.

In addition, the lower layer of the grain layer is mainly composed of ultrafine fiber bundles, and the ultrafine fibers and/or bundles thereof that form part of the grain layer are obtained by subdividing the ultrafine fiber bundles in the lower layer into ultrafine fibers. Preferably, the fibers are substantially continuous in the grain layer and the lower layer, and the boundary between the two layers is finely divided into ultrafine fibers and/or densely entangled. A fiber structure in which the degree of entanglement changes continuously is more preferable because a sheet product with a sense of unity can be obtained and the grain layer and the lower layer will not peel off. Furthermore, in the lower layer of the grain layer, ultrafine fiber bundles and fine fibers subdivided from the bundles are intertwined with each other, and the fibers are substantially continuous between the grain layer and the lower layer, and the fibers are substantially continuous in the thickness direction. A fiber structure with simply different entanglement densities is even more preferable because a sheet material with a unified feel and high strength can be obtained.

In addition, conventional leather-like sheet materials that use nonwoven fabric as a base material are easily stretched by external forces and are difficult to return to their original shape because the deformation is plastic.
To prevent this, resin has been applied to the base material.

However, the flexible leather-like sheet material according to the present invention, which has a fiber structure in which ultrafine fibers and/or bundles thereof are densely intertwined at least in the grain layer, does not elongate abnormally even if no resin is applied to the lower layer. The shape retention of the sheet material is good. Note that, depending on the purpose, a commonly used resin may be used as the binder, but in order to maintain a soft texture, it is preferable to use an amount of 0 to 10 parts based on the weight of the fibers.

The resin used in the silver surface layer of the present invention is a urethane polymer, and particularly preferably polyester diol, polyether diol, polyether ester diol, polycaprolactone diol, or polycarbonate diol having an average molecular weight of 600 to 3000 is used in the soft segment. It is a urethane polymer obtained by reacting at least one type of polymer diol selected from diols with an organic diisocyanate and a compound having at least two active hydrogen atoms as a chain extender.

In addition, it is not limited to substantially linear type urethane polymers,
In some cases, it may be a crosslinked urethane polymer crosslinked with a crosslinking agent such as hexamethylene diisocyanate puree. Generally, when a cross-linked type urethane polymer is used for the grain layer, it has good scratch resistance but poor bending fatigue resistance and properties.However, in the present invention, the grain layer is made of dense fibers Since it is formed as a composite of the urethane polymer and the urethane polymer, it is preferable because it has excellent bending fatigue resistance and is effective in improving hot water resistance.

Further, other polymers such as polyamide, polyester, polyvinyl chloride, polyvinyl butyral, polyamino acid, polyamino acid polyurethane copolymer, silicone resin, etc., or a mixture thereof may be mixed with the above urethane polymer as necessary. good. Furthermore, if necessary, plasticizers, fillers, stabilizers, crosslinking agents, colorants, etc. may be added. Furthermore, in addition to urethane polymers, products containing other resins and additives give particularly flexible texture and feel.
It is preferably used because a durable grain layer can be obtained.

Furthermore, a cross-linked urethane polymer may be applied to the surface of the grain layer of the present invention to a thickness of 0.2 to 10 microns, preferably 0.2 to 4 microns.

The adhesion structure of the resin mainly composed of urethane polymer in the grain layer is not particularly limited.It varies depending on the purpose, but if flexibility and soft feel are particularly required, such as for clothing, Those with a structure in which more of the resin is attached as it gets closer to the surface, or the very thin layer on the outermost surface of the grain layer has a particularly large amount of resin attached, and the rest have no resin attached at all or even if it is attached. Preferably, the structure is such that the amount is small. In addition, when particularly high scratch resistance is required, a structure in which the voids in the grain layer are filled with resin almost without any gaps is preferable.

One of the intended objectives of the present invention is to have a silver surface with a very smooth touch, a firm, dense, full feeling, and supple texture, as well as shrinkage and wrinkles due to washing. A flexible leather-like sheet material with excellent dimensional stability with almost no changes in appearance such as flow can be obtained by simply coating the urethane polymer used for the grain layer on a conventional porous sheet. You can't get it. This can only be achieved by combining a densely entangled fiber tangled body and applying the shrinkage treatment method described below.

Here, in the conventional technology, when processing a sheet material mainly having a nonwoven fabric structure, it is common to perform a shrinkage treatment such as hot water treatment in one of the processing steps, mainly for the purpose of improving fiber density. be. In order to obtain a more flexible sheet material, it is preferable to use a method such as mixing a component with excellent hot water shrinkability and removing the component after sufficient shrinkage in the hot water shrink treatment process. ing. In addition, more flexible sheet materials can be obtained by increasing the mixing ratio of the removed components and by reducing or not applying the binder resin used for the purpose of fixing dimensions and/or improving texture. It will be done. However, the more flexible the material is made by these methods, the worse the dimensional stability becomes.

Dimensional stability is also poor in the case of the polyamide used in the present invention, and even worse after washing under tension in wet conditions. Furthermore, if there is a grained grained surface, the quality will be significantly impaired due to grain flow, etc.

The silver surface of the present invention has excellent scratch resistance and a very smooth touch, and has a firm, dense, full-feeling, and supple texture, and is resistant to changes in appearance such as shrinkage and grain loss due to washing. A flexible leather-like sheet material with very good dimensional stability is obtained by treating a fibrous sheet with an emulsion of aromatic alcohol, drying it, and shrinking it. requires an area shrinkage rate of 5% or more due to the treatment. Area shrinkage rate is 5
%, the effects of the present invention cannot be obtained. Further, it is more preferable that the area shrinkage rate is 10% or more because stable effects can be obtained.

Here, the step of treating the fibrous sheet with an emulsion of aromatic alcohol is not particularly limited, but if the treatment is performed after shrinking the fibrous sheet by hot water treatment etc.
This is a preferable method because the irregularities on the surface of the sheet can be controlled to a small level and a uniform sheet can be obtained. Further, it is more preferable to perform the treatment after the ultrafine fibers are finely divided and/or densely entangled by spraying a high-speed fluid stream on them, since efficient shrinkage can be achieved. Furthermore, when using an ultrafine fiber-forming multicomponent fiber, forming a grain layer and then forming ultrafine fibers from the ultrafine fiber-forming fiber,
When the treatment is carried out after that, it is particularly preferably used because it allows more efficient and uniform shrinkage, requires less drying time, and allows the grain layer to be integrated into a high density layer.

Further, depending on the purpose, after the treatment, the surface may be smoothed by passing it through a calender roll or the like.

Aromatic alcohols that can be used in the present invention include phenol, 0-cresol, m-cresol, p-
Cresol, catechol, resorcinol, hydroquinone,
There are xylenol, phenylphenol, chlorophenol, benzyl alcohol, phenylethyl alcohol, etc., but benzyl alcohol and phenylethyl alcohol are preferably used because of their large shrinkage effect, ease of making emulsions, stability, and ease of handling. Benzyl alcohol is particularly preferably used because it has good shrinkage efficiency and is inexpensive.

Further, the concentration of the aromatic alcohol varies depending on the type used, but is preferably 2% by weight or more and 50*% by weight or less,
If it is less than 2% by weight, it is difficult to achieve the intended purpose and is therefore undesirable, and if it exceeds 50% by weight, it is generally undesirable because it causes large unevenness in shrinkage. In particular, a content of 5% by weight or more and 30% by weight or less is more preferable because stable processing can be achieved. The state of the emulsion is not particularly limited, and may be either an emulsion or a transparent liquid as long as it is uniformly dispersed.

Processing and drying in the present invention basically refers to immersing the fibrous sheet in the above emulsion, washing it, and then drying it. I don't mind if you do. Further, during the treatment, heating may or may not be performed, and is not particularly limited to either, but heating is preferable because better shrinkage efficiency can be obtained. Further, the treatment time varies depending on the fibrous sheet used, the type of emulsion, the treatment temperature, etc., but in any case, it is sufficient as long as it is sufficient to uniformly wet the fibrous sheet with the emulsion. Further, washing after the immersion treatment may be performed by either water washing or hot water washing, but a temperature range of 40° C. or higher and 80° C. or lower is preferable because good shrinkage efficiency can be obtained.

A more specific explanation of the method for producing a flexible leather-like sheet material of the present invention, which consists of a combination of the above-mentioned steps (1) to (2) or (2) to (2), is as follows, for example.

First, ultrafine fiber-forming multicomponent fibers are produced using a spinning apparatus disclosed in, for example, Japanese Patent Publication No. 18369/1983,
After being stapled, a web is formed by passing through a card and a cross wrapper, which is then needle punched to entangle the ultrafine fiber-forming fibers to form a fiber sheet. Alternatively, the ultrafine fiber-forming multicomponent fibers are spun and then drawn, placed randomly on a wire mesh, and the obtained web is needle punched in the same manner as described above to form a fiber sheet.

Alternatively, the ultrafine fiber-forming multicomponent fibers are placed on a nonwoven fabric, woven fabric, or knitted fabric made of ordinary fibers or other ultrafine fiber-forming multicomponent fibers, and are inseparably integrated to form a fiber sheet. You can.

Next, a case will be described in which the fiber sheet obtained in this way is brought into contact with a high-speed fluid stream to be finely divided into ultrafine fibers and/or to be densely entangled.

The fluid here refers to a liquid or a gas, and in special cases it may contain extremely fine solids, but from the viewpoint of ease of handling, cost, and amount of collision energy as a fluid, water is Most preferably used. Furthermore, depending on the purpose, various organic solvents capable of dissolving some components of the ultrafine fiber-forming multicomponent fiber, or aqueous solutions of alkali or acids such as sodium hydroxide can be used. These fluids are pressurized to form a nozzle with a small pore diameter or a curtain-like flow with narrow intervals, and are brought into contact with the fiber sheet to finely divide and/or entangle the ultrafine fibers. The pressure applied to the liquid varies depending on the ease with which the ultrafine fiber-forming multicomponent fibers or ultrafine fiber bundles are finely divided and/or densely entangled. Then 5~100g/crr
A relatively low pressure of r is sufficient, but for fibers that are difficult to subdivide and/or become densely entangled, the pressure may be 100 to 300 g/crrr.
A high pressure of . It is also possible to increase the degree of subdivision and/or dense entanglement by increasing the number of times of contact, and the pressure may be changed each time of contact. Further, it is also possible to perform a shrinkage treatment in hot water of 70 to 100° C. to increase the density, and this treatment may be performed before the high-speed fluid flow treatment.

After that, if it is necessary to make the used ultrafine fiber-forming multicomponent fiber ultrafine, the ultrafine fiber-forming multicomponent fiber is subjected to physical action to cause it to peel off, or at least a portion of it is removed. The obtained fiber sheet is treated with a solvent capable of dissolving the components to dissolve and remove some of the components, thereby making it extremely fine. Further, if necessary, the resin may be impregnated with a solution or dispersion using a commonly used resin as a binder, and coagulated by a wet or dry method. Here, the part of the component may be dissolved and removed before the treatment with the high-speed fluid flow, and in this case, by dissolving and removing the part of the component, the ultrafine fiber-forming multicomponent fiber of the fiber sheet becomes the ultrafine fiber. This is a preferred method because it allows for easy, highly fragmented and/or dense entanglement at low fluid pressures. Furthermore, high-speed fluid flow treatment may be performed before and after the step of dissolving and removing the partial components. In addition to the above, the step of applying the binder resin can be carried out between the high-speed fluid flow treatment step and the step of dissolving and removing some components of the fibers. It is necessary that the applied binder resin is not dissolved in the solvent used to dissolve and remove the partial components, but a space where the partial components were present is created between the obtained fiber sheets, and mutual movement is prevented. This is a preferred method for making the texture soft because it increases the degree of freedom. On the other hand, when high-speed fluid flow treatment is performed after applying the binder resin, when a large amount of resin is applied, the fibers are bound by the resin, so fine segmentation and/or dense entanglement is not performed. This is not a desirable method. After drying, at least one side of the obtained fiber sheet is subjected to a treatment such as pressing to smooth the surface, and the solution or dispersion of the silver surface resin described above is applied to at least one side.

Next, the fibers of the grain layer and the resin are further integrated using a heated pressure roll, and the surface is smoothed. In this case, it is preferable to use an embossing roll with a textured surface because smoothing and texture formation can be performed at the same time. Further, the above-mentioned partial dissolution and removal of the ultrafine fiber-forming multicomponent fiber can also be carried out after such grain surface formation, and in this case it is particularly preferable because a softer texture can be obtained. Furthermore, as described above, it is treated with an emulsion of aromatic alcohol and dried to achieve high shrinkage.

The flexible leather-like sheet material thus obtained may be further subjected to dyeing treatment, finishing treatment, rolling treatment, etc., if necessary.

[Effects of the Invention] The flexible leather-like sheet material obtained by the method of the present invention has
It has excellent scratch resistance such as resistance to rubbing and shear fatigue, has a silver surface with an extremely smooth touch, has a firm, dense, full feeling, and supple texture, and also resists shrinkage when washed Because it has excellent dimensional stability with almost no changes in appearance such as grain or grain flow, it is ideally used for a variety of applications such as bags, belts, gloves, footwear, bags, and ornaments, and is also used for clothing, including parts. is particularly preferably used.

[Examples] The following examples are provided to clarify the present invention, and the present invention is not limited thereto.

In each example, parts and percentages are by weight unless otherwise specified. Moreover, the value of the distance between intersection end points was taken as the average value of 100 measured values.

Examples 1 to 4, Comparative Example 1 One filament was prepared at a ratio of 40 parts of nylon-6 as the island component forming the ultrafine fibers and 60 parts of a copolymer of acrylic acid and styrene (hereinafter referred to as AS resin) as the sea component. 3.5 of a polymer array fiber having 7 island components in it and further including a large number of ultrafine fibers in the island component.
Using a denier, 51 mm staple, a web was formed through a card/cross wrapper, and then needle punched to form a web with a fabric weight of 390 g/rr? A nonwoven fabric with an apparent density of 0.19 g/cm3 was obtained.

Once on each side of this nonwoven fabric, pore size 0.25 m
m% 100kgy using a 2.5mm pitch nozzle
A high-speed water stream of CRD pressure is sprayed into contact with the nonwoven fabric while moving the nozzle, and then the nonwoven fabric is subjected to shrinkage treatment in hot water at 85°C to shrink in area by 31%. After drying, it is pressed to smooth the surface. I made it. Then, on the surface of the nonwoven fabric, cross-linked polyester polyurethane was applied at a solid content of 2 g/m2, and then polyether polyurethane was added at a solid content of 1 g/m2.
2 was applied, and a leather-like grain pattern was embossed with an embossing roll.

Thereafter, the sea component was almost completely extracted and removed using trichlorethylene to obtain a leather-like sheet material.

Then, the leather-like sheet material was treated with an emulsion of 25% benzyl alcohol (including 3% surfactant: alkyl sulfosuccinate) under various conditions (Examples 1 to 4), dried, and then used with a calendar roll. The surface was smoothed and dyed with a 1=2 type metal-containing dye using a Wins type dyeing machine, and then rubbed. For comparison, we also prepared a sample that was not treated with benzyl alcohol (Comparative Example 1).
) were similarly processed, and the details are as listed in Table 1.

The leather-like sheet products of Examples 1 to 4 obtained according to the present invention had a firm, dense and full texture, and had a very smooth silver surface to the touch. . Furthermore, the silver surface scratch resistance was excellent.

When this leather-like sheet material was dry cleaned,
For the untreated specimens, there were conditions in which the area shrinkage rate exceeded 3%, and the change in appearance of the silver surface was also poor, but for the treated specimens, all the results were excellent.

Examples 5 to 8, Comparative Example 2 One filament had 7 island components, with 40 parts of nylon-6 as the island component forming the ultrafine fibers and 60 parts of As resin as the sea component. Using 3.5 denier, 5 lmrn staples of polymer array fibers containing many ultrafine fibers in the island component, a web was formed through a card/cross wrapper, and then needle punched to form a web with a basis weight of 175 g. /rrl',
Nonwoven fabrics (A) and (B) with an apparent density of 0.18 g/cm3
) was obtained. In exactly the same way, 35 parts of nylon-6 and A
65 parts of S resin has a basis weight of 179 g/r! Nonwoven fabrics (C) and (D) having an apparent density of 1' and an apparent density of 0.18 g/cm3 were obtained.

A high-speed water stream of 100 kg/crrf pressure was applied to each of the nonwoven fabrics (A), (B), (C), and (D) once using a nozzle with a hole diameter of 0.25 mm and a pitch of 2.5 mm. The nozzle was moved while making contact with the spray.

Next, the nonwoven fabric was shrinked with hot water at 85°C and dried to obtain nonwoven fabrics (A) and (B) with an area shrinkage rate of 33% and an area shrinkage rate of 4.
3% nonwoven fabrics (C) and (D) were obtained.

Of the nonwoven fabrics, (A) and (C) were each immersed in a 15% benzyl alcohol (surfactant: 2% polyoxyethylene alkyl ether) emulsion with a bath temperature of 70°C for 20 minutes, and then in water for 30 minutes. After standing for a minute, it was dried at 100°C. The area shrinkage rate due to this treatment is 1 for the nonwoven fabric (A).
8.3%, and nonwoven fabric (C) 5.6%.

Next, each of the nonwoven fabrics (A), (B), (C), and (D) was subjected to surface smoothing treatment using a calendar roll, and 2 g of crosslinked polyester polyurethane was applied to the surface in solid content.
lrd, then polyether-based polyurethane was applied with a solid content of Ig/rrr, and a leather-like grain pattern was embossed with a hot embossing roll.

Thereafter, the sea component was almost completely extracted and removed using trichlorethylene to obtain a leather-like sheet material.

Furthermore, it was dyed with a 1:2 type metal-containing dye using a Wins type dyeing machine, and then rubbed.

The leather-like sheet material obtained in this way has a firmness that makes it hard to believe that it is a thin material, has a dense and rich texture, and has a very smooth silver surface to the touch. The scratch resistance of the surface was also improved.

When this leather-like sheet material was subjected to chlorine-based dry cleaning, the untreated levels (B) and (D) showed poor changes in the appearance of the silver surface, but the treated levels (A) and (
C) was improved, and in particular, level (A) was sufficiently satisfactory.

Claims (1)

[Claims] (1) At least the following (1) to (3), or (1)
A method for producing a flexible leather-like sheet material, characterized by combining the steps from ) to (4). (1) A step of obtaining a fibrous sheet having a three-dimensional entanglement of ultrafine polyamide fibers or ultrafine fiber-forming multicomponent fibers that generate ultrafine polyamide fibers by mechanical manipulation or chemical treatment. (2) The fibrous sheet obtained in step (1) is treated with an emulsion of aromatic alcohol and dried to produce a fibrous material whose shrinkage due to the treatment is 5 or more in terms of area shrinkage Sa expressed by the following formula I. Process of obtaining sheets. Sa=(S_0-S_1)/S_0×100...
・I However, Sa: Area shrinkage rate (%) S due to the treatment
_0: Area before the treatment S_1: Area after the treatment (3) A step of applying a urethane polymer to at least one side of the fibrous sheet to make it grainy. (4) When ultrafine fiber-forming multicomponent fibers are used in step (1), a step of forming ultrafine fibers from the ultrafine fiber-forming multicomponent fibers. (2) A method for producing a flexible leather-like sheet material according to claim (1), characterized in that the area shrinkage rate Sa is 10% or more. (3) Prior to the step (2) of treating the fibrous sheet with an emulsion of aromatic alcohol and drying it to shrink it, a shrinkage treatment is performed in advance with hot water and/or hot air. A method for producing a flexible leather-like sheet material according to item (1) or item (2). (4) Claim (1) characterized in that the ultrafine fiber-forming multicomponent fiber is divided into ultrafine fibers and/or the ultrafine fibers are three-dimensionally entangled by spraying a high-speed fluid stream. , the method for producing a flexible leather-like sheet material according to item (2) or item (3). (5) Claims (1) and (2) characterized in that the aromatic alcohol is benzyl alcohol.
), (3) or (4). (6) Claim (1), characterized in that the aromatic alcohol is phenylethyl alcohol;
The method for producing a flexible leather-like sheet material according to item (2), item (3), or item (4). (7) Claims (1) and (2) characterized in that the ultrafine fiber is 0.2 denier or less.
Section, Section (3), Section (4), Section (5), or Section (
6) The method for producing a flexible leather-like sheet material as described in section 6). (8) A patent claim characterized in that the three-dimensional entanglement of ultrafine fibers performed by a high-speed fluid flow is a dense entanglement of 200 microns or less in the distance between fiber entanglement points of the ultrafine fibers and/or bundles thereof. A method for producing a flexible leather-like sheet material according to scope item (4).