JP2001131880A - Oil-tone leather-like sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an oil-tone leather-like sheet having high-class appearance and the same degree of soft feeling and touch feeling as those of natural leather, useful for application to shoes, and the like. SOLUTION: This oil-tone leather-like sheet comprises a napped sheet which is composed of an interlaced nonwoven fabric made of extra fine fibers containing a polyurethane and in which napped fibers composed of the extra fine fibers exist on a part or the whole face of at least one side. A compounded material of an oily substance having 50-10,000 mPa.s viscosity at 30 deg.C and its holding body exists on a part of the whole face of the napped sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil-finished leather-like sheet which has a high-grade appearance, has a soft texture and a touch similar to that of natural leather, and is useful for application to shoes and the like.

[0002]

2. Description of the Related Art In recent years, with the background that outdoor activities have been regarded as important for recreation, shoes with a casual feeling using natural leather or artificial leather materials have been increasing in fashion. In particular, the oil-like material of natural leather has a moist touch and the natural calm appearance of natural leather, and is therefore preferred as a material for high-end zones as a material for shoes. Artificial leather is used as a material for shoes because it is lighter in weight than natural leather.However, in order to express a moist touch like oil-like material of natural leather, its structure is Up,
It is necessary to perform some surface treatment. Conventionally, not only artificial leather but also synthetic leather has been proposed as a surface finishing coating agent. For example, JP
Japanese Patent Application Laid-Open No. 1-285268 describes a method using a surface coating agent obtained by mixing polybutylene and silica in a resin containing polyurethane as a main component. Also, JP-A-1-139
No. 877 describes a method for incorporating an oil-soluble surfactant. However, although these methods improve the surface touch, they cannot reproduce the original touch of moist oil-like natural leather.

[0003]

Means for Solving the Problems The present inventors have conducted intensive studies on a leather-like sheet having both a high-grade appearance and the moist touch feeling of oil-like natural leather, and as a result, found that entangled fibers made of ultrafine fibers were obtained. The nonwoven fabric contains polyurethane, and at least a part or the whole surface of the nonwoven fabric has a nap made of the ultrafine fibers.
It has been found that the above-mentioned object is achieved by an oil-finished leather-like sheet in which a composition comprising an oily substance of 0 mPa · s and its carrier is present. In the present invention, it is particularly preferable that the support is an olefin-based elastomer or a vinyl aromatic-based elastomer. Among them, as a preferred example of the olefin-based elastomer, a hydrocarbon group having 1 to 8 carbon atoms as a side chain is preferable. 5 to 60 units having a side chain with respect to the ethylene unit constituting the main chain.
Examples of the vinyl aromatic elastomer include a polymer block A composed of a vinyl aromatic compound and a polymer block composed of a conjugated diene. Examples include a block copolymer having B or a hydrogenated product thereof. It is preferable that the weight ratio of the oily substance to the support is 1: 1 to 20: 1.

Hereinafter, the present invention will be described in detail. The support of the oily substance constituting the present invention is a polymer substance exhibiting the property of an elastomer at normal temperature, so-called thickness of 0.5 mm.
When the sheet is stretched at room temperature at 100% or more at room temperature, it is easily deformed when an external force is applied, but is immediately restored to its original shape when removed, and the powder of the polymer elastic body is combined therewith. The powder is immersed in an oily substance to be used, left at room temperature for 24 hours, and naturally filtered to absorb 200% or more of the weight of the oily substance by absorption of the oily substance. Alternatively, when a vinyl aromatic elastomer is used, preferable results are obtained. In particular, as an example of the olefin-based elastomer, an ethylene polymer having 5 to 60 mol% of a unit having a side chain having 1 to 8 carbon atoms with respect to an ethylene unit constituting the main chain, or a block copolymer having an ethylene polymer block may be used. Examples of the vinyl aromatic elastomer include a block copolymer having a polymer block A composed of a vinyl aromatic compound and a polymer block B composed of a conjugated diene compound, or the block copolymer. Examples include hydrogenated block copolymers obtained by hydrogenation. In the case of these supports, particularly preferable results are obtained in terms of the retention of oily substances.

Hereinafter, an olefin elastomer which is a preferred example of the support constituting the present invention will be described. The olefin-based elastomer is a resin having a hydrocarbon chain as a center, and has a segment having a glass transition point of room temperature or lower. Such examples include, for example, EPR (ethylene propylene rubber), EBR (ethylene-butylene rubber), HBR (hydrogenated butadiene rubber), and the like.
Methods for producing these polymers are known, and as the main raw material monomers, for example, olefins such as ethylene, propylene, butene, and octene are required as one essential component, and if necessary, isobutylene, cyclopropene, cyclobutene, cyclopentene, cyclooctene, Cyclooctadiene,
A cyclic hydrocarbon compound such as butadiene, isoprene, norbornene, or a diene-based hydrocarbon compound can be used in combination. These monomers are appropriately mixed and polymerized by an existing polymerization method, for example, radical polymerization, anionic polymerization, or cationic polymerization. In some cases, hydrogenation is performed to improve final physical properties, particularly weather resistance. A particularly good olefin-based elastomer is a copolymer of ethylene and an α-olefin. Examples of the α-olefin include propylene, butene, pentene, hexene, heptene, octene, nonene and the like. Although the polymerization method is not particularly limited, the polymerization is usually performed in the presence of a Zieglar-Natta catalyst or a metallocene catalyst. In this case, an ethylene polymer in which the content of the unit having a side chain derived from an α-olefin is 5 to 60 mol% based on the ethylene unit constituting the main chain is particularly excellent in elastomeric properties and retention of oily substances. . Although the molecular weight of the olefin-based elastomer is not limited, it is tens of thousands to hundreds of thousands. In some cases, a small amount of a monomer other than the α-olefin may be copolymerized. Such monomers include styrene, butadiene, isobutylene, and the like.

Next, a description will be given of a vinyl aromatic elastomer which is a preferred example of the support constituting the present invention. Generally contains a styrene unit as a hard segment,
A polymer having a resin portion having a glass transition point at room temperature or lower as a soft segment is a typical example of a vinyl aromatic elastomer. Among them, generally, SBS (triblock copolymer composed of styrene polymer block butadiene polymer block-styrene polymer block), SEBS
(Styrene polymer block-Ethylene-butadiene copolymer block-Styrene polymer block triblock copolymer), SEPS (Styrene polymer block-Ethylene propylene copolymer block-Styrene polymer block triblock) Resins such as copolymers) can be used as a suitable block copolymer.

A block copolymer which is a particularly preferred vinyl aromatic elastomer or a block copolymer which is a base of a hydrogenated block copolymer thereof will be described. There are no particular restrictions on the number of polymer blocks A and polymer blocks B in the block copolymer. Here, when the polymer block A is represented by A and the polymer block B is represented by B, preferred block copolymer structures are AB, (A-
B) n, (AB) n-A, (BA) nB (however,
N represents an integer of 1 to 10 in these structural formulas),
(AB) m X (X represents a residue of an m-valent coupling agent, and m represents an integer of 2 to 15). Above all, a triblock copolymer represented by ABA is particularly preferable from the viewpoint of oily substance retention. In the block copolymer, the content of the vinyl aromatic compound is preferably from 5 to 75% by weight in view of the retention of the oily substance, and more preferably from 10 to 65% by weight.

Examples of the vinyl aromatic compound constituting the polymer block A in the block copolymer include styrene, α-methylstyrene, o-, m- or p-methylstyrene, 1,3-dimethylstyrene, vinyl Examples include naphthalene and vinylanthracene. Of these, styrene or α-methylstyrene is preferred in terms of flexibility. The vinyl aromatic compounds may be used alone or in combination of two or more. Examples of the conjugated diene constituting the polymer block B in the block copolymer include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, and 1,3-butadiene.
Examples include pentadiene and 1,3-hexadiene. Among these, isoprene, 1,3-butadiene or a mixture thereof is preferred in terms of flexibility. The conjugated dienes may be used alone or in combination of two or more.

The structure of the polymer block B in the block copolymer is not particularly limited except that it is composed of a conjugated diene, and the content of 1,2-bonds and 3,4-bonds is not limited. There is no particular limitation.

The number average molecular weight of the block copolymer is not particularly limited, but is preferably 50,000 to 500,000, more preferably 100,000 to 400,000. If it is less than 50,000, the retention of the oily substance is reduced, and if it exceeds 500,000, the flexibility is reduced.

Although such a block copolymer is already known, for example, the following known anionic polymerization method can be used as a production method thereof. That is,
A block copolymer is formed by polymerizing a vinyl aromatic compound and a conjugated diene in an inert organic solvent such as n-hexane or cyclohexane using an alkyllithium compound or the like as an initiator. At this time, if desired, a coupling agent such as dichloromethane, carbon tetrachloride, or tetrachlorosilane may be used.

When the block copolymer is a hydrogenated product of the above block copolymer, the block copolymer is hydrogenated in an inert organic solvent in the presence of a hydrogenation catalyst according to a known method. Can be obtained.

In the present invention, when the above block copolymer or a hydrogenated block copolymer which is a hydrogenated product thereof is used as the support, the hydrogenated block copolymer is preferably used from the viewpoint of heat resistance and weather resistance. And more preferably 70% or more of the carbon-carbon double bond derived from the conjugated diene in the block copolymer before hydrogenation is hydrogenated. The content of the carbon-carbon double bond in the polymer block B in the hydrogenated block copolymer can be determined by an iodine value measurement, an infrared spectrophotometer, a nuclear magnetic resonance method, or the like. In addition to the above two types of blocks, other monomers may be copolymerized in a block shape or at random within a range that does not impair the present invention. The styrene-based elastomer includes a styrene-containing rubber such as SBR (styrene-butadiene rubber) in addition to the above-described block copolymer.

Further, as for the resin constituting the support used in the present invention, a carboxyl group, a hydroxyl group, an acid anhydride group, an amino group, an epoxy group or the like may be added in the molecular chain or at the molecular terminal unless the gist of the present invention is impaired. And the like.

The oily substance blended in such a support has a viscosity at 30 ° C. of 50 to 10,000 mPa.
A liquid substance that is s and is substantially incompatible with water at normal temperature and phase-separated is used. When the viscosity is less than 50 mPa · s, the oily component migrates sharply after being applied to the napped surface, and the oily feeling of the surface changes greatly with time. On the other hand, when it exceeds 10,000 mPa · s, it is unsuitable because it does not mix with the holder and has a thin oily feeling. Specific examples of the types of oily substances include paraffinic or naphthenic process oils, white oils, mineral oils, oligomers of ethylene and α-olefins, paraffin wax, liquid paraffin, silicone oils, vegetable oils, aromatic oils, and the like. These are used alone or in combination. Among them, a paraffinic process oil is preferred.

In the present invention, the weight ratio of the support (1) to the oily substance (2) is preferably (2) / (1) = 1 to 20. If the weight ratio is less than 1, a moist oily feeling is not exhibited, and if it exceeds 20, the bleeding of the oily substance occurs and the appearance of the oil-finished leather-like sheet tends to change with time. It is not preferable because there is. More preferably, it is in the range of (2) / (1) = 3-12.

In the present invention, the kind and molecular weight of the support (1), the ratio of the kind of the oily substance (2) and the quantity when two or more kinds of oily substances are mixed and used, and (2) / (1) By changing the ratio and the amount of application to the surface, any touch from oily type to waxy type in the oil-like natural leather material can be reproduced.

Next, the napped nonwoven fabric composed of microfibers used in the present invention contains polyurethane, and the napped nonwoven fabric composed of the ultrafine fibers is partially or wholly present on at least a part or all of one surface thereof. The sheet will be described. The sheet is made of an entangled nonwoven fabric composed of ultrafine fibers of 0.3 denier or less, and polyurethane contained therein. The average fineness of the fibers constituting the sheet must be 0.3 denier or less, and is preferably in the range of 0.1 to 0.0001 denier. When the thickness exceeds 0.3 denier, the tapped feel becomes rough and the appearance deteriorates. If it is less than 0.0001 denier, the breaking strength of the fiber tends to be low, the peel strength and the breaking strength of the layer tend to be low, and sufficient coloring properties tend not to be obtained.

As a method for producing ultrafine fibers, there is no compatibility in the molten state, and the fibers have different solubility or degradability.
A method for producing sea-island structural fibers by a mixed spinning method, a sea-island composite spinning method using a polymer of at least one kind, a method of producing a splittable composite fiber by a composite spinning method, and the like; Typical examples include a method of extracting and decomposing and removing a part (for example, a sea component) of the split composite fiber to form an ultrafine fiber, and a method of exfoliating a polymer interface of a splittable conjugate fiber to obtain an ultrafine fiber. In addition to this method, a method such as a so-called melt blow method in which the fiber is blown off with a high-speed gas immediately after the fiber-forming polymer is discharged from the melt spinning nozzle to make the fiber thinner can be used. However, it is preferable to use the above-described ultrafine fiber-generating fiber from the viewpoint of controlling the fiber thickness and the stability of the ultrafine fiber.

The resin constituting the ultrafine fibers is not particularly limited, but aromatic polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and copolymer polyesters containing these as a main component, nylon And polyamides such as -6, nylon-66 and nylon-610, and polyolefins such as polyethylene and polypropylene. Among them, the aromatic polyesters and polyamides are preferable in that natural leather-like artificial leather can be obtained and the dyeability is excellent. Further, a coloring agent such as a pigment or a dye represented by carbon black may be added to these resins as long as the stability during spinning is not impaired.

Examples of the resin component constituting the ultrafine fiber-generating fiber which is extracted or decomposed and removed include polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polystyrene, and styrene-acryl. Examples include at least one polymer selected from polymers such as a system monomer copolymer, a styrene-ethylene copolymer, and a copolymerized polyester. Among them, polyethylene, polystyrene, copolymers mainly composed of these, and the like are preferable in terms of ease of extraction.

Next, as a method for forming an entangled nonwoven fabric containing polyurethane using the above-mentioned ultrafine fibers or ultrafine fiber-generating fibers, a known method, for example, manufacturing an entangled nonwoven fabric made of ultrafine fiber-generating fibers is used. This can be achieved by sequentially performing a process, a process of impregnating the entangled nonwoven fabric with a polyurethane solution and coagulating, and a process of modifying the ultrafine fiber-generating fibers into ultrafine fibers. Of course, the step of modifying into ultrafine fibers and the step of impregnating and coagulating polyurethane may be reversed. As a method for producing an entangled nonwoven fabric using the ultrafine fiber-generating fiber, the ultrafine fiber-generating fiber is subjected to spinning, stretching, heat setting, crimping, cutting, and the like by a conventionally known method, and the same fiber is processed. Making raw cotton, defibrating such raw cotton with a card, forming a random web or cross-wrap web with Weber, laminating the obtained web as necessary,
A typical example is a method for obtaining a desired weight. At this time, the weight of the web is appropriately selected depending on the intended final use field, and is generally preferably in the range of 100 to 3000 g / m ² . For the purpose of cost reduction, etc., the polyurethane solution is impregnated and coagulated into an entangled non-woven fabric about twice the required weight, and then divided in the thickness direction with a band knife or the like, so that the non-woven fabric can be efficiently cut at a time. One piece of substrate can also be manufactured. Subsequent to lamination of the web, an entangled nonwoven fabric is formed by performing an entanglement treatment using a known method such as a needle punching method or a high-pressure water jet method. The number of needle punching and the conditions for needle punching vary depending on the shape of the needle used and the thickness of the web, but generally 20 needle punching.
It is preferable to set in the range of 0 to 2500 punches / cm ² .

Prior to the polyurethane-containing treatment, the entangled nonwoven fabric may be subjected to a surface smoothing treatment, if necessary, by a known method such as hot pressing. When the fibers constituting the entangled nonwoven fabric are, for example, sea-island structural fibers in which polyethylene is the sea component and polyester or polyamide is the fine island component, the polyethylene in the sea component is fused by hot pressing to separate the fibers. By bonding and fixing, an entangled nonwoven fabric having extremely excellent surface smoothness can be obtained. When the fibers constituting the entangled nonwoven fabric are not sea-island structural fibers that can be dissolved and removed as one component and modified into ultrafine fibers, the contained polyurethane is fixed to the fibers to prevent the texture from becoming hard. Preferably, the fiber surface is covered with a temporary filling material such as polyvinyl alcohol prior to the polyurethane impregnation treatment, and the temporary filling material is removed after the polyurethane is applied. Also, in the case of sea-island structure fibers that can be made into ultrafine fibers by dissolving or decomposing and removing one component, the provisional filling material is applied at the stage of the entangled nonwoven fabric to cover the surface of the multicomponent fiber. Thus, a more flexible sheet can be obtained.

Next, as a resin to be contained in the entangled nonwoven fabric, a polyurethane resin is used from the viewpoint of a feeling. Preferred polyurethane resins include, as soft segments, polyester-based diols, polylactone-based diols, polycarbonate-based diols, polyether-based diols, polyether-ester-based diols, etc. obtained by reacting a diol with a dicarboxylic acid or an ester-forming derivative thereof. Having a number average molecular weight of 5 selected from the group consisting of
A so-called segmented polyurethane obtained by using at least one kind of polymer diol of from 0 to 5000 and reacting the diisocyanate compound with a low molecular chain extender is used.

As the diol compound used for the synthesis of the polyester diol constituting the soft segment, an aliphatic compound having 6 to 10 carbon atoms is preferable in terms of durability or leather-like texture. 1,5-pentanediol, 1,6-hexanediol, 2-methyl-1,8-octanediol, 1,
Examples thereof include 9-nonanediol and 1,10-decanediol. Representative examples of dicarboxylic acids include aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, azelaic acid, and sebacic acid, and aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid.

The number average molecular weight of the polymer diol is 500
If it is less than 10%, it is not preferable because it lacks flexibility and a natural leather-like texture cannot be obtained. When the number average molecular weight of the polymer diol exceeds 5,000, the urethane group concentration decreases, so that it is difficult to obtain a leather-like sheet having a balance in flexibility, durability, heat resistance, and hydrolysis resistance. As the diisocyanate compound, 4,4′-
Diphenylmethane diisocyanate, xylylene diisocyanate, tolylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-
Examples thereof include aromatic, aliphatic, and alicyclic diisocyanate compounds such as diisocyanate and hexamethylene diisocyanate. Examples of the low molecular chain extender include ethylene glycol, propylene glycol, butanediol, hexanediol, N-methyldiethanolamine, ethylenediamine, diaminodiphenylmethane,
Low-molecular compounds having two active hydrogen atoms having a molecular weight of 300 or less, such as diaminodicyclohexylmethane and isophoronediamine, are exemplified. The method for synthesizing the polyurethane may be a one-shot method or a prepolymer method. Also, if necessary, polyurethane
A coagulation regulator, a stabilizer and the like may be added, and another polymer may be used in combination. Further, a coloring agent such as carbon black or a dye may be added.

The method of incorporating polyurethane into the entangled non-woven fabric is not particularly limited, but the polyurethane solution is directly impregnated into the entangled non-woven fabric in view of the balance of the texture.
If necessary, a method of squeezing with a mangle or a method of impregnating a polyurethane solution while coating it with a coater is preferable. The polyurethane is contained in the entangled nonwoven fabric by wet coagulation or dry coagulation of the impregnated polyurethane solution, but the wet coagulation method is particularly preferred since a natural leather-like texture and feel can be obtained. Further, the polyurethane may be used in an emulsion liquid. From the viewpoint of a natural leather-like soft texture, the weight ratio of the ultrafine fibers and polyurethane constituting the sheet is preferably in the range of 30/70 to 80/20, and more preferably in the range of 35/65 to 55/45. It is. If the ratio of the fibers is too low, the leather-like sheet has a rubber-like texture, which is not preferable. If the ratio of the fibers is too high, the texture becomes a paper-like texture, and the target natural leather-like texture cannot be obtained.

When the sea-island structure fiber is used, after the polyurethane is contained in the entangled nonwoven fabric, the non-solvent and ultra-fine fiber generating fiber of the non-solvent and the island component of the ultra-fine fiber generating fiber are removed. The components are treated with a solvent or a liquid that acts as a decomposer to transform the ultrafine fiber-generating fibers into ultrafine fiber bundles to form a sheet comprising the ultrafine fiber entangled nonwoven fabric and polyurethane. Needless to say, the sheet may be formed by using a method of transforming the ultrafine fiber-generating fibers into an ultrafine fiber bundle before adding the polyurethane. In the case of using a splittable splittable composite fiber,
A method is used in which an ultrafine fiber bundle is formed by treating with a liquid that promotes separation to cause separation at the interface of the fiber constituent polymer.

Raising of the sheet made of the obtained entangled nonwoven fabric of ultrafine fibers and polyurethane can be carried out by a known method such as buffing and styling. Since the fluff length to be raised affects the appearance and the appearance after applying the holding body containing the oily substance, the conditions of the buff and the hair trimming, for example, the count of the sandpaper used for the buff, the cutting speed and the pressing pressure. The fluff length is adjusted by selecting the above. The nap may be present on the entire surface of one side of the sheet, may be present on the entire surface of both surfaces, or may be present in a spot on one or both surfaces.

In the present invention, the composition comprising the oily substance and the support is applied or impregnated so as to be present on at least a part of the raised surface of the sheet. In the case of applying, a known method can be used as the method, for example, a method of hot-melt coating the composition by hot melting or a composition in which the oil and the support are dissolved in a common solvent. Is applied using a coating method such as gravure roll, spray, direct coating and the like. A preferred method is gravure coating. When a gravure roll is used, 55 to 200 mesh is preferably used. As a suitable coating amount, it is preferable to apply 1 to 50 g of the composition per 1 m ² of the sheet surface. In the case where the composition contains a solvent, the coating amount referred to herein means the total amount of the oil and the support excluding the solvent. When the coating amount is less than 1 g / m ² , the feeling of oil is insufficient, and when it exceeds 50 g / m ² , the feeling of nap is lost and the texture becomes hard. In the present invention, the composition is applied to the surface of the fluff. However, it is not preferable that the fluff is entirely covered with the composition and the fluff is not substantially present on the surface. In the oil-finished leather-like sheet of the present invention, the composition is fixed to the sheet surface by fluff fibers, and the composition hardly falls off the fluff surface even if some surface friction is applied to the sheet surface.

The oil-finished leather-like sheet thus obtained is useful not only as shoes but also as a material for gloves, bags, clothing and the like.

[0032]

EXAMPLES Next, the present invention will be described with reference to specific examples, but the present invention is not limited to these examples. The parts in the examples relate to weight unless otherwise specified. The thickness of the fiber is determined from the average value of the cross-sectional area using an electron micrograph of the fiber cross section. Further, in the examples, the appearance and oily feeling were visually observed on the surface of the leather-like sheet,
The inventors made a judgment based on the tactile sensation. The evaluation results are
Good: O, normal: Δ, poor: X

Production Example 1 Nylon-6 and polyethylene in the form of a chip in a ratio of 50: 5
The mixture was melt-spun by an extruder, and a sea-island structural fiber in which polyethylene was a sea component and nylon-6 was an island component was spun, stretched, crimped, and cut to obtain a fiber.
A denier, 51 mm long staple fiber is produced, a cross wrap is made with a weber, and a 70% needle piercing machine is used.
Needle punching of 0 punch / cm ² was performed to obtain an entangled nonwoven fabric. This nonwoven fabric is impregnated with a dimethylformamide solution of a polyurethane resin having a poly-3methylpentane adipate diol having an average molecular weight of 2,000 and polyethylene glycol as a polymer diol for a soft segment, and wet-coagulated. Extracted with perchlor ethylene, with a basis weight of 450 g /
A substrate having a m ² , a thickness of 1.3 mm, and a polyurethane resin to fiber ratio of 63/37 was obtained. The fineness of the obtained nylon ultrafine fibers of the substrate was 0.006 denier on average. One surface of the obtained substrate was buffed with sandpaper to obtain a sheet having a raised surface made of the nylon ultrafine fibers.
When this sheet was dyed using a circular dyeing machine under the following conditions, a brown raised leather-like sheet was obtained. Dyeing conditions Dye: Lancron Brown S-GR 5% owf Irgalan Yellow GRL 2% owf Bath ratio: 1:30 Dyeing temperature: 90 ° C.

Example 1 A hydrogenated product of a triblock copolymer of styrene- (isoprene / butadiene) -styrene having an average molecular weight of 290,000 (Septon 4055: an elastomer manufactured by Kuraray Co., Ltd .; hydrogenation ratio: 98%) A weight increase of 1600% after standing at room temperature for 24 hours in the following oil;
A toluene solution (block copolymer concentration = 3%) in which paraffinic oil (PW-90: manufactured by Idemitsu Kosan; viscosity at 30 ° C .: 140 mPa · s) was blended as an oily substance with a weight ratio of 5 times to this support. ) Was prepared and coated on the raised surface of the raised leather-like sheet obtained in Production Example 1 above using a 55-mesh gravure roll in an amount such that the applied amount was 6 g / m ^{2 in} the total amount of the holder and the oily substance. And dried to evaporate the toluene. The obtained leather-like sheet had a moist and calm appearance and feel. In addition, when I pulled this leather-like sheet, the stretched part turned white, and when I stopped pulling, it returned to the original color tone,
It was very similar to so-called oil-like natural leather.

Example 2 A leather-like sheet was obtained in the same manner as in Example 1, except that the blending amount of the oily substance was 12 times that of the hydrogenated product of the block copolymer. The obtained leather-like sheet had a moist and calm appearance and touch as in Example 1. Further, when the leather-like sheet was pulled, the stretched portion turned white, and when the pulling was stopped, the color returned to the original color, which was very similar to so-called oil-like natural leather.

Example 3 As a support, styrene-isoprene- having an average molecular weight of 80,000 was used.
A hydrogenated product of a triblock copolymer of styrene (Septon 2007: an elastomer manufactured by Kuraray Co., Ltd .; hydrogenation ratio: 98%; weight increase after standing at room temperature in the following oil for 24 hours at 1600%) A toluene solution (block copolymer concentration = 1%) was prepared by mixing a paraffinic oil (PW-380: manufactured by Idemitsu Kosan; viscosity at 30 ° C .: 600 mPa · s) at a weight ratio of 8 times as an oil. The solution was applied to the surface of the napkin-like sheet obtained in Production Example 1 in an amount such that the applied amount was 4 g / m ^{2 in} terms of the total amount of the support and the oily substance. After drying, an oil-finished leather-like sheet was prepared. The obtained leather-like sheet had a moist and calm appearance and feel. Further, when the leather-like sheet was pulled, the stretched portion turned white, and when the pulling was stopped, the color returned to the original color, which was very similar to so-called oil-like natural leather.

Example 4 EPR (EP961SP: Elastomer manufactured by JSR Corporation): Weight increase after standing at room temperature for 24 hours at room temperature for 24 hours, content of side chain hydrocarbon group was 20 mol %), And a toluene solution (block copolymer concentration = 1%) in which a paraffin-based oil (PW-380: manufactured by Idemitsu Kosan; viscosity at 30 ° C .: 600 mPa · s) is mixed as an oil in a weight ratio of 2 times. And applying the solution to the surface of the napkin-like sheet obtained in Production Example 1 in an amount such that the applied amount is 4 g / m ^{2 in} terms of the total amount of the holder and the oily substance, and then the dryer at 70 ° C. After drying in the oven for 20 minutes, an oil-finished leather-like sheet was prepared. The obtained leather-like sheet had a moist and calm appearance and touch as in Example 1. Further, when the leather-like sheet was pulled, the stretched portion turned white, and when the pulling was stopped, the color returned to the original color, which was very similar to so-called oil-like natural leather.

Comparative Example 1 A leather-like sheet was obtained in the same manner as in Example 1, except that no oily substance was used. The obtained leather-like sheet had a rubber-like texture, had a bulky touch, had no oily feeling, and did not change color tone even when pulled.

Comparative Example 2 A leather-like sheet was obtained in the same manner as in Example 1, except that no support was used. The obtained leather-like sheet had a smooth touch, no slimy feeling peculiar to oil tone, and the oil adhered to the hand when touched. Further, the touch changed over time immediately after the application, and the amount of oil attached decreased with time.

Table 1 shows the performance of the leather-like sheets obtained in the above Examples and Comparative Examples.

[0041]

[Table 1]

[0042]

The oil-finished leather-like sheet of the present invention preferably has (1) a hydrocarbon group having 1 to 8 carbon atoms as a side chain and a side chain with respect to the ethylene unit constituting the main chain. Ethylene polymer having 5 to 60 mol% of units, block copolymer having an ethylene polymer block, and polymer block A comprising a vinyl aromatic compound
And at least one elastomer selected from the group consisting of a block copolymer having a polymer block B comprising a conjugated diene and a hydrogenated product thereof; and (2)
An oily substance, wherein the weight ratio of (1) and (2) is (2) /
(1) A composition having 1 to 20 is applied to the raised surface of a raised leather-like sheet in which polyurethane is contained in an entangled nonwoven fabric made of ultrafine fibers of 0.3 denier or less and fluff is present on the surface. As a result, it has a high-grade oil-like appearance, and has a soft texture and touch feeling equivalent to that of natural leather, and is useful for application to shoes and the like.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F055 AA03 AA30 BA13 CA18 DA07 EA03 EA11 EA24 FA15 FA17 HA17

Claims (6)

[Claims] An entangled nonwoven fabric comprising ultrafine fibers contains polyurethane, and at least a part or the whole surface of the entangled nonwoven fabric has a nap made of the ultrafine fibers on a part or the whole of the raised surface. , Viscosity at 30 ° C. is 50-
An oil-finished leather-like sheet, wherein a mixture comprising an oily substance of 10,000 mPa · s and a support thereof is present. 2. The oil-finished leather sheet according to claim 1, wherein the support is an olefin-based elastomer. 3. The oil-finished leather sheet according to claim 1, wherein the support is a vinyl aromatic elastomer. 4. An ethylene polymer having a side chain of a hydrocarbon group having 1 to 8 carbon atoms and having 5 to 60 mol% of a unit having a side chain with respect to an ethylene unit constituting a main chain. 3. The oil-finished leather sheet according to claim 1, which is a block copolymer having an ethylene polymer block. 5. The block copolymer according to claim 1, wherein the support is a block copolymer having a polymer block A composed of a vinyl aromatic compound and a polymer block B composed of a conjugated diene, or a hydrogenated product thereof. Oil-like leather-like sheet. 6. The weight ratio of the oily substance to the support is from 1/1 to 20.
The oil-finished leather-like sheet according to any one of claims 1 to 5, wherein the ratio is / 1.