JPH0149832B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing a leather-like sheet product having a silver surface and consisting of densely intertwined ultrafine fibers, bundles thereof, and resin. The grain layer of conventional artificial leather is formed from a porous or non-porous layer made of resin such as polyurethane elastomer, or a layer formed by laminating a porous layer and a non-porous layer. ing.
However, it is formed from these silver layers.
However, these artificial leathers with a silver layer have a poor overall sense of unity and have a strong rubber-like repulsive feel.
It has drawbacks such as being easily scratched and having a uniform surface gloss with no depth. In addition, in order to improve these defects, there are those in which a grain layer is formed by adding various fillers such as fine particles to the resin, and those in which a grain layer is formed by combining a planar arrangement of fine fiber bundles and a porous material. , one in which the fluffy fibers on the surface and resin are integrated to form a silver surface,
It has been proposed to create a surface by melting or dissolving surface fibers and partially bonding them to form a silver surface layer. However, the addition of fillers has the problem of reducing the bending strength and gloss of the grain surface. Because the fibers are arranged in an array, if they are strongly rubbed or subjected to repeated shear stress, the surface becomes fluffy or peels along the arrayed surface of the fiber bundles, resulting in a defect called "silver flakes". As this progresses, there is a problem that cracks occur on the surface, and there is also a problem that fine irregularities occur on the surface along the bundle of fine fibers, deteriorating the appearance. Also,
The problem with these materials is that if they are repeatedly bent or subjected to repeated shear stress, cracks or cracks will occur on the surface relatively easily, resulting in extremely poor appearance. The present inventors have fully considered the problems of conventional artificial leather, and have developed a leather-like sheet material that does not have the above-mentioned problems and has particularly high bending resistance, kneading resistance, shearing resistance, and scratch resistance. In order to provide the same, we have made extensive studies on the manufacturing method and finally arrived at the present invention. That is, the present invention has the following configuration. That is, the method for manufacturing a leather-like sheet according to the present invention is a method for manufacturing a leather-like sheet product characterized by sequentially performing at least the following steps. A step of forming a fiber sheet using ultrafine fiber-forming fibers having a cross section in which a plurality of ultrafine fibers of 0.2 denier or less are interposedly bonded by other components in at least the surface layer portion. (a) Bringing the obtained fiber sheet into contact with a high-speed fluid flow to impart branching and entanglement of the ultrafine fibers while destroying or dissolving intervening components, or (b) applying the ultrafine fibers After dissolving and removing some components of the formed fibers and transforming them into bundles of ultrafine fibers, a high-speed fluid stream is brought into contact with the ultrafine fibers to branch and intertwine them, resulting in ultrafine fibers of 0.2 denier or less. and forming a fiber structure in which the distance between fiber entanglement points of the ultrafine fibers and/or bundles thereof is 200 microns or less. A step of applying a resin to the surface layer of the obtained fiber structure and coagulating or solidifying the resin to form a grain layer made of a composite of fibers and resin on at least one side. The leather-like sheet material obtained by the present invention has a grain layer comprising ultrafine fibers and/or bundles thereof.
It is basically a composite consisting of a resin existing in the void portion, and the ultrafine fibers and/or their bundles are densely intertwined with each other.
This combination made it possible for the first time to provide a leather-like sheet material with a supple texture, smooth surface feel, and good bending resistance, shear fatigue resistance, kneading resistance, and scratch resistance. It is. The ultrafine fibers used in the present invention may be ultrafine fiber-forming fibers made by adhesively bonding bundles of ultrafine fibers directly produced by a method such as super draw using a glue (intervening component) such as polyvinyl alcohol. However, if the fibers become thin, the spinning becomes unstable, and processing is difficult and difficult to handle. Therefore, it is recommended to use the ultra-fine fiber forming type fiber described below and convert it into ultra-fine fiber at an appropriate time during the processing process. is preferred. That is, the ultrafine fiber-forming fiber used in the present invention includes, for example, a fiber made of ultrafine fibers bundled and bonded together with other components, and a chrysanthemum-shaped cross section in which one component is radially interposed between other components. Fibers, multilayer bimetallic fibers, multilayer bimetallic fibers with a donut-shaped cross section, sea-island fibers made by melt-mixing and spinning two or more components, a large number of ultrafine fibers that are continuous in the fiber axis direction, and are combined and assembled with other components. The fibers may be polymeric mutual array fibers that are partially combined to form a single fiber, and two or more types of these fibers may be mixed or used in combination. Ultrafine fiber-forming fibers that have a cross section in which multiple ultrafine fibers are interveningly bonded and/or partially bonded by other components can be relatively easily formed into ultrafine fibers by applying physical action or removing bonded components. Therefore, it is particularly used in the method of the present invention. In particular, in order to obtain a very densely entangled fiber structure with a distance between fiber entanglement points of 200 microns or less, when one component is dissolved and removed, 0.2
It is necessary to use ultrafine fiber-forming fibers that can yield bundles of fibers mainly consisting of ultrafine fibers with a denier or less, and more preferably, can yield fiber bundles mainly consisting of ultrafine fibers with a denier of 0.05 or less. It is desirable to use ultrafine fiber-forming fibers composed of multiple components in order to obtain a leather-like sheet material that has a particularly supple feel and smooth surface. Further, the ultrafine fibers in the present invention are made of polymeric substances having fiber-forming ability, such as polyamides such as nylon 6, nylon 66, nylon 12, copolymerized nylon, polyethylene terephthalate, copolymerized polyethylene terephthalate, polybutylene tetophthalate, Polyester such as copolymerized polybutylene terephthalate, polyethylene,
Examples include polyolefins such as polypropylene, polyurethane, polyacrylonitrile, and vinyl polymers. In addition, examples of the binding component or the dissolving and removing component of the microfiber-forming fiber include polystyrene, polyethylene, polypropylene, polyamide, polyurethane, copolymerized polyethylene terephthalate that is easily soluble in alkaline solutions,
Polyvinyl alcohol, copolymerized polyvinyl alcohol, styrene-acrylonitrile copolymer, copolymer of styrene and higher alcohol ester of acrylic acid, etc. are used. Polystyrene and styrene are easy to spin and easy to dissolve and remove.
Acrylonitrile copolymers, 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 because it can obtain a high stretching ratio and a fiber with high strength. 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 ultrafine fiber-forming fibers is not particularly limited, but is from 1 to 1 from the viewpoint of stability during spinning, ease of sheet formation, etc.
10 denier is preferred. The ultrafine fibers in the grain layer of the present invention have a fineness of
As mentioned above, it is necessary to use a material with a denier of 0.2 denier or less. If it is thicker than 0.2 denier,
Excessive rigidity of the fibers not only impairs the flexibility of the grain layer and the form of wrinkles on the surface, but also causes cracks to easily occur when rubbed, etc., resulting in unevenness on the surface, resulting in the formation of a dense and supple grain layer. It's difficult. 0.2
By using ultrafine fibers with a denier or less, preferably 0.05 denier or less, and by applying a high-speed fluid flow to the fiber sheet, the fibers can be tightly intertwined, smooth and supple. A leather-like sheet material is obtained which has a grainy layer that is resistant to cracking and feels good in the hand. The fiber structure in the grain layer of the leather-like sheet of the present invention requires that ultrafine fibers and/or bundles thereof are densely intertwined with each other. In other words, the fiber entanglement density is high. One way to measure the fiber entanglement density is to measure the distance between fiber entanglement points, which will be described later, but the fibers in the grain layer have an entanglement density of 200μ or less as measured by this method. It is necessary. This value
Those with a structure larger than 200 μ, for example, those with a fiber structure with little entanglement in which fibers are entangled only by needle punching, or those with a structure in which ultrafine fibers or bundles thereof are simply arranged in a plane, or those with a structure in which ultrafine fibers or bundles thereof are arranged in a plane. Materials with a structure in which the surface is created by forming a dense fluff-like fluff on the surface of the base material have little or no entanglement of fibers, so the surface becomes fluffy or cracks when subjected to abrasion, kneading, repeated shearing force, etc. This is not desirable because it tends to cause In order to eliminate these drawbacks, it is necessary that the distance between fiber entanglement points be 200μ or less. More favorable results can be obtained when the thickness is 100μ or less. Here, the distance between fiber entanglement points is a value obtained by the following method, and as a measure of the denseness of fiber entanglement, the smaller the value, the more dense the entanglement is. It is. FIG. 1 is an enlarged schematic diagram of the constituent fibers in the grain layer when observed from the surface side. The constituent fibers are f ₁ ,
Any two fibers f ₁ among f ₂ , f ₃ , ...
The point where f ₂ is intertwined is a _1. Trace _the upper fiber f ₂ to the point where it intersects under the other fibers, and _the intersecting point is a ₂ point). Similarly, let a ₃ , a ₄ , a ₅ ,... Next, the linear horizontal distances between the intersecting points obtained in this way are a ₁ a ₂ , a ₂ a ₃ , a ₃ a ₄ ,
a ₄ a ₅ , a ₅ a ₆ , a ₇ a ₈ , a ₈ a ₉ , a ₈ a ₇ , a ₇ a ₉ , a ₉ a ₆ ,...
is measured, and the average value of these many measured values is determined, and this is taken as the distance between fiber entanglement points. In addition, the lower layer of the grain layer is mainly intertwined with ultrafine fiber bundles, and the ultrafine fibers and/or their bundles in the grain layer are branched ultrafine fiber bundles in the lower layer and intertwined more closely. A fiber structure in which the fibers are substantially continuous in the grain layer and the lower layer, and the degree of branching changes continuously at the boundary between the two layers has a unified texture. It is preferably used because a sheet product can be obtained and the grain layer and the lower layer will not peel off. Here, the thickness of the ultrafine fiber bundles in the grain layer does not need to be the same for all bundles, but is as thin as possible compared to the thickness of the bundle in the lower layer (the number of fibers included in the bundle is smaller than that in the bundle in the lower layer). It is preferable that the surface of the sheet is less likely to have unevenness on the surface of the sheet. In addition, conventional leather-like sheets that use nonwoven fabric as a base material are easily stretched by external force when the base material is made of fibers, and deformation is plastic, making it difficult to return to the original shape. Therefore, resin was applied to the base material. However, the leather-like sheet material obtained by the present invention, which has a fiber structure in which ultrafine fibers and/or bundles thereof are densely intertwined, is unlikely to stretch abnormally even if no resin is added to the lower layer. Good shape retention of objects.
This is also a major feature of the leather-like sheet material obtained by the method of the present invention. Of course, a resin such as a polyurethane elastomer may be applied to the lower layer, and the amount of resin applied varies depending on the intended use of the sheet material. When used for clothing, the amount applied is preferably 0 to 80 parts based on the weight of the fiber. Examples of the resin used for the silver layer include polyamide, polyester, polyvinyl chloride, polyacrylate copolymer, polyurethane, neoprene, styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, polyamino acid, and polyamino acid polyurethane copolymer. synthetic resins such as silicone resins, natural polymer resins, or mixtures of these resins. Furthermore, if necessary, plasticizers, fillers, stabilizers, pigments, dyes, crosslinking agents, etc. may be added. Polyurethane resins or polyurethane resins to which other resins and additives are added are preferably used because they have a particularly soft feel and feel and provide a grain layer with good bending resistance. There are no particular limitations on the adhesion structure of the resin on the silver layer, and it may vary depending on the purpose.
When flexibility and soft feel are particularly required, such as for clothing, products with a structure in which more resin is deposited closer to the surface of the grain layer, or a very thin layer of resin deposited on the outermost surface of the grain layer, are used. Particularly large in number, and others have a structure in which no resin is attached at all or even if it is attached, only a small amount, or a structure in which the resin on the surface is non-porous and the rest is porous. etc. are preferable. Further, 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. When carrying out the method for producing a leather-like sheet material of the present invention, the ultrafine fiber-forming fibers are first produced using a spinning apparatus as disclosed in Japanese Patent Publication No. 18369/1983, stapled, and passed through a card or a cross wrapper. A web is formed and then needle punched to intertwine the microfiber-forming fibers to form a fiber sheet. Alternatively, following the spinning of the microfiber-forming fibers, they are stretched and 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 fibers are placed on a nonwoven fabric, woven fabric, or knitted fabric made of ordinary fibers or other ultrafine fiber-forming fibers, and the fibers are entangled and inseparably integrated to form a fiber sheet. Next, the fiber sheet thus obtained is brought into contact with a high-speed fluid stream to branch into ultrafine fibers and/or bundles thereof, and at the same time to entangle them densely. The fluid referred to here is a liquid or a gas, and in special cases it may contain extremely fine solids, but water is the most suitable in terms of ease of handling, cost, and amount of collision energy as a fluid. Preferably used. Furthermore, depending on the purpose, various organic solvents capable of dissolving some components of the ultrafine fiber-forming fibers, or aqueous solutions of alkalis or acids such as sodium hydroxide can also be used. These fluids are pressurized and injected from small-diameter nozzles or narrowly spaced slits to form a high-speed columnar or curtain-like flow, which is brought into contact with the fiber sheet to branch and entangle the fibers. The pressure applied to the liquid is
It depends on the ease of branching of the ultrafine fiber-forming fiber or ultrafine fiber bundle, and for fibers that are easy to branch, a relatively low pressure of 5 to 70 kg/cm ² may be sufficient.
For fibers that are difficult to branch, high pressures of 70 to 300 kg/cm ² are required. It is also possible to increase the degree of branching and entanglement by increasing the number of contacts, and the pressure may be changed each time the contacts are made. Thereafter, if necessary to make the used ultrafine fiber-forming fibers ultrafine, the obtained fiber sheet is treated with a solvent that dissolves some components of the ultrafine fiber-forming fibers. Dissolve and remove components. Further, if necessary, it is impregnated with a solution or dispersion of a binder resin such as a polyurethane elastomer and coagulated by a wet or dry method. here,
The partial component may be dissolved and removed before being treated with a high-speed fluid stream, and in this case, the ultrafine fiber-forming fibers of the fiber sheet are transformed into a bundle of ultrafine fibers by dissolving and removing the partial component. This is a preferred method because it allows easy and highly branched and entangled results at low fluid pressures. Also,
High-speed fluid flow treatment may be performed before and after the step of dissolving and removing some components. In addition to the above, the step of applying the binder resin can also be carried out between the high-speed fluid flow treatment step and the step of dissolving and removing some components of the fibers. Although it is necessary that the applied resin is not dissolved by the solvent used to dissolve and remove the partial components, a space where the partial components were present is created between the ultrafine fiber bundles of the obtained fiber sheet and the resin. This is a preferred method for making the texture more flexible as it increases the degree of freedom in mutual movement. On the other hand, performing high-speed fluid flow treatment after applying binder resin is a preferable method because when a large amount of resin is applied, the fibers are bundled thinly with resin, so branching and entanglement hardly occur. do not have. Thereafter, the solution or dispersion of the resin for the grain layer described above is applied to the surface layer of the obtained fiber sheet where the ultrafine fibers and/or their bundles are intertwined by reverse roll coating, gravure coating, knife coating, slit coating, or spraying. Coagulate or solidify by wet or dry method, stack on the roll surface or sheet surface, pressurize, heat if necessary,
It integrates fibers and resin and at the same time smoothes the surface. Here, it is also a preferable method to subject the fiber sheet to a treatment such as pressing to smooth the surface before applying the resin. At this time, it is preferable to use an emboss roll or a textured sheet with a textured pattern on the surface because integration, smoothing, and texture formation can be performed at the same time. Furthermore, treatments such as applying a finishing agent, dyeing, and rubbing may be performed as necessary. The leather-like sheet material thus obtained by the method of the present invention has a supple texture, a smooth surface feel, and has good bending resistance, shear fatigue resistance, kneading resistance,
Due to its good scratch resistance, it can be used as silver-finished artificial leather for clothing, shoe uppers, handbags, bags, belts, etc.
It is preferably used for various purposes such as bags, gloves, and ball leather. The examples shown below are intended to make the present invention more clear, and the present invention is not limited thereto. In the examples, parts and percentages are by weight unless otherwise specified. In addition, the value of the average intercrossing point distance was taken as the average value of 100 measured values. Example 1 A vinyl-based polymer (hereinafter referred to as AS resin) copolymerized with 20 parts of 2-ethylhexyl acrylate and 80 parts of styrene was used as a binding component, and nylon 6 was used as a microfiber component in a ratio of 40 parts. 4.0 denier, 51 mm of polymer mutually arranged fibers as shown in Japanese Patent Publication No. 47-37648, which has 16 island components in the filament and further contains a large number of ultrafine fiber components in the island components. A web was formed through a card cross wrapper using staples, and then needle punching was performed using a needle with one hook to bond the polymer interlayer fibers to produce a nonwoven fabric (A). Non-woven fabric (A) has a basis weight of 405g/m ² and an apparent density of 0.20g/cm ²
It was hot. Water with a pressure of 100 kg/cm ² is sprayed onto the surface of the nonwoven fabric (A) at high speed from a nozzle in which holes with a diameter of 0.1 mm are arranged in a row with a center-to-center distance of 0.6 mm while moving the nonwoven fabric (A). 5 times in total under the same conditions and
The treatment was carried out 10 times, and then the pressure was lowered to 50 kg/cm ² and the same treatment was performed once each for the 5-time treatment and the 10-time treatment while vibrating the nozzle. I made it. Obtained nonwoven fabric
(B) and nonwoven fabric (C) had a fiber structure in which the surface layer of mutually arranged polymer fibers was branched into ultrafine fibers or bundles thereof with an average fiber size of about 0.1 denier, and were densely intertwined with each other. . Next, nonwoven fabrics (A), (B), and (C) were prepared by chain-extending a prepolymer of a mixed diol of polyethylene adipate and polybutylene adipate and p,p'-diphenylmethane diisocyanate with ethylene glycol. The resulting polyurethane was impregnated with a 7% dimethylformamide (hereinafter referred to as DMF) solution, the liquid adhering to the surface was removed with a scraper, and the solution was introduced into water and solidified. Thereafter, the DMF was removed by thorough washing in hot water at 80°C. After drying, soak it in trichlorethylene, immerse it, and re-squeeze the liquid.
The AS resin was almost completely extracted and removed, followed by drying and residual trichlorethylene was removed by evaporation. The water-treated side of the sheets obtained from nonwoven fabrics (B) and (C) was extremely smooth with few irregularities, but the surface of the sheet obtained from nonwoven fabric (A) was extremely fine with no branches. The fiber bundle had unevenness and poor smoothness. Next, a solution of pigment added to a 10% solution of polyurethane, which has the same composition as the polyurethane used for impregnation but has a slightly harder hardness, was applied to the surface layer of these sheets using a gravure coater, and dried. After solidification, it was pressed through a heated embossing roll to emboss a leather-like grain pattern. Furthermore, it was dyed using a jet dyeing machine under normal pressure, and finishing processing was performed using a conventional method. The leather-like sheets obtained from nonwoven fabrics (B) and (C) had a smooth surface that followed the grain pattern, and had a soft and unified texture.
In addition to the grain pattern, the leather-like sheet material obtained from (A) has irregularities along the ultra-fine fiber bundles, such as protruding blood vessels, and there are also irregularities along the ultra-fine fiber bundles that occur during dyeing. There were cracks and ultra-fine fibers were exposed. The polyurethane and finishing agent applied to these leather-like sheets were extracted and removed with a solvent, and the distance between fiber entanglement points of the constituent fibers on the surface of the grain layer was measured. The average distance between fiber entanglement points is 361μ for nonwoven fabric (A), 193μ for nonwoven fabric (B), and 193μ for nonwoven fabric (C).
The value was 77μ. Furthermore, the results of measuring the bending resistance, shear fatigue resistance, and scratch resistance of these leather-like sheet materials are as shown in Table 1. From this, it can be seen that the leather-like sheet products produced by the method of the present invention using nonwoven fabrics (B) and (C) have better bending resistance, shear fatigue resistance, and scratch resistance than those using nonwoven fabric (A). It turned out to be something.

【table】

[Table] Example 2 Polyvinyl alcohol (hereinafter referred to as PVA) prepared by heating the nonwoven fabric (A) produced in Example 1 to 95°C.
% aqueous solution to shrink the nonwoven fabric at the same time as PVA impregnation, dry it to remove moisture, then dip it in trichlorethylene, and repeat the immersion and squeezing process.
The resin was extracted and removed and dried. The obtained nonwoven fabric is a nonwoven fabric in which ultrafine fibers are entangled with each other in a substantially bundled manner, and both sides of this fabric are coated with 50%
Water under a pressure of Kg/cm ² was sprayed at high speed, and each surface was treated a total of three times under the same conditions to dissolve the PVA and at the same time branch and entangle it. The final treatment was carried out while vibrating the nozzle, and after removing the PVA, the sample was passed through a mangle while still containing water, and then dried. The surface layer of the obtained nonwoven fabric had a fiber structure in which the original ultrafine fiber bundles were highly branched and densely intertwined. After that, one side was lightly buffed with sandpaper, and a polyurethane solution was applied to the surface layer of the other side using a gravure coater.
After that, a leather-like sheet material was produced in the same manner as in Example 1. Although the resulting leather-like sheet material has a substantially fixed form only by intertwining the fibers,
It had good shape retention, a fiber structure very similar to natural leather, excellent flexibility, and a full texture. Furthermore, when the folded end was pinched with one's fingers, it exhibited a rounded feel and shape similar to that of natural leather, and no cracks or fuzz were observed even when strongly rubbed or pulled by hand. When this leather-like sheet coat was made, it had a very elegant appearance without any paper-like creases. The polyurethane and finishing agent on the grain layer of this leather-like sheet were removed with a solvent, and the average distance between fiber entanglements of the constituent fibers was measured and found to be 13μ. Example 3 95 parts of polystyrene and 5 parts of polyethylene glycol
A 3.8 denier, 51 mm piece of polymer interlayer array fiber in a form in which 16 ultrafine fibers are contained in one filament, with 45 parts of a mixture of 50% and 50% of polyethylene terephthalate as a binding component and 55 parts of polyethylene terephthalate as an ultrafine fiber component. A nonwoven fabric was made using the same method as in Example 1. The basis weight of this nonwoven fabric is 540g/
m ² and thickness was 2.8 mm. On one side of this nonwoven fabric,
Using the same nozzle as in Example 1, a columnar flow of water injected at a pressure of 70 kg/cm ² was brought into contact with
The pressure was lowered to 30 Kg/cm ² and the treatment was carried out twice. Furthermore, they were placed in hot water at 95°C for shrinkage treatment and mangle nips. The thickness of the obtained entangled nonwoven fabric was reduced to about 1.8 mm, and a layer of about 1/4 of the thickness from the water-treated surface was composed of fibers branched from the polymeric mutually arranged fibers with an average fineness of about 0.15 denier and bundles thereof. The main body was densely packed, and the surface had very few irregularities. Thereafter, using the same impregnating solution of polyurethane as in Example 1 with a concentration of 10%, impregnation, coagulation, hot water washing, and drying were carried out in the same manner. Next, polystyrene and polyethylene glycol are dissolved and removed using trichlorethylene, sliced into 1.1 mm thick slices, and a coating made by adding carbon black and dye to a polyurethane solution is applied to the water jet treated surface layer using a gravure coater. The composite was then dried and solidified, pressed and integrated to form a composite, and then textured. The other side was buffed to fluff the microfibers, then dyed at a high temperature of 120°C using a disperse dye, and then finished as usual. The resulting leather-like sheet material has a texture with low repulsion and a sense of unity, with one side having relatively long fluff of ultra-fine fibers, and the other side having a silver surface with an elegant appearance. It had a structure very similar to natural silver-plated leather. Also, when this material was used as the upper of a shoe, it was found that the toe of the conventional material had "Rabbi" on the toe.
However, with the shoes of the present invention, such unevenness did not occur and a shoe with a smooth surface was obtained. Furthermore, when the shoes were worn, they were extremely resistant to scratches compared to shoes with conventional polyurethane coatings. After removing the polyurethane and finishing agent from the grain layer of this leather-like sheet, the average distance between fiber entanglements of the constituent fibers was measured and found to be 98μ. Example 4 One filament has 16 island components with a ratio of 68 parts of AS resin as a binding component and 32 parts of nylon 6 as an ultrafine fiber component, and the island component contains many ultrafine fiber components. A 4.0 denier, 51 mm staple of polymer interlayer fibers in the form of The arrayed fibers were combined to create a nonwoven fabric. The nonwoven fabric had a basis weight of 200 g/m ² and an apparent density of 0.14 g/cm ² . Water under a pressure of 100 kg/cm ² is sprayed from a nozzle in which holes with a diameter of 0.25 mm are arranged in a row with a distance of 1.0 mm between the centers of the holes, while the nozzle is oscillated, and the nonwoven fabric is transported on a conveyor. caused a collision. Next, turn the nonwoven fabric over and turn it over to the other side (side
The same treatment was carried out once each from the side at pressures of 75 Kg/cm ² , 50 Kg/cm ² and 10 Kg/cm ² . The obtained nonwoven fabric had a fiber structure in which the surface layer of mutually arranged polymer fibers was branched into ultrafine fibers or bundles thereof having an average fiber density of about 0.003 denier, and were densely intertwined with each other. The average distance between fiber entanglement points was 85μ. After that, it was immersed in hot water at 85°C to shrink and press, and after drying, it was pressed again. After that, a 7% solution of cross-linked two-component polyurethane is applied using a gravure coater, applied to the surface layer of the nonwoven fabric side, dried and solidified, and passed through a heating roll to integrate the fibers to form a composite. At the same time, the surface was smoothed. Next, it was immersed in trichlorethylene, and the immersion and squeezing process was repeated.
The AS resin was almost completely extracted and removed, followed by drying and residual trichlorethylene was removed by evaporation. Furthermore, it was dyed using a jet dyeing machine under normal pressure, finished by a conventional method, and then subjected to a rolling process using a rolling machine. The resulting leather-like sheet material has a smooth surface with fine wrinkles, good shape retention and high scratch resistance despite the absence of binder resin, and is extremely flexible and has a sense of unity. It had a nice texture. Furthermore, the basis weight is 98g/m ² and the thickness is 0.37mm.
Because it was so thin, it had excellent drapability and could be used to make shirts and dresses.

[Brief explanation of drawings]

FIG. 1 is an enlarged schematic diagram of the constituent fibers in the grain layer when observed from the surface side.

Claims (1)

[Scope of Claims] 1. A method for producing a leather-like sheet product, which comprises sequentially carrying out at least the following steps. A step of forming a fiber sheet using ultrafine fiber-forming fibers having a cross section in which a plurality of ultrafine fibers of 0.2 denier or less are interposedly bonded by other components in at least the surface layer portion. (a) Bringing the obtained fiber sheet into contact with a high-speed fluid flow to impart branching and entanglement of the ultrafine fibers while destroying or dissolving intervening components, or (b) applying the ultrafine fibers After dissolving and removing some components of the formed fibers and transforming them into bundles of ultrafine fibers, a high-speed fluid stream is brought into contact with the ultrafine fibers to branch and intertwine them, resulting in ultrafine fibers of 0.2 denier or less. and forming a fiber structure in which the distance between fiber entanglement points of the ultrafine fibers and/or bundles thereof is 200 microns or less. A step of applying a resin to the surface layer of the obtained fiber structure and coagulating or solidifying the resin to form a grain layer made of a composite of fibers and resin on at least one side.