JP2017043859A - Sheet-like material and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet-like material which includes a fiber-entangled body, and in which raised ultrafine fibers are uniformly oriented; and to provide a method for producing the same.SOLUTION: A method for producing a sheet-like material includes the steps of: providing a sheet including a fiber-entangled body mainly composed of ultrafine fibers having an average single fiber diameter of 0.01-8 μm with a liquid in an amount of 1-300 mass% based on the mass of the sheet; feeding the obtained sheet to a buff roll; and, without applying external force directly opposed to the buff roll from the opposite side of the buff roll with the sheet interposed in between, subjecting a surface on the side of the sheet in contact with the buff roll to wet buffing, thereby raising the fibers on one surface of the sheet. There is also provided the sheet-like material which includes the fiber-entangled body mainly composed of the ultrafine fibers having the average single fiber diameter of 0.01-8 μm, and in which one surface or both surfaces of the sheet-like material are formed of fiber-raised surfaces. The ultrafine fibers which are arranged in a longitudinal direction on at least one surface of the fiber-raised surfaces have a fiber orientation rate in a transverse direction of 40-95%.SELECTED DRAWING: None

Description

  The present invention relates to a method for producing a sheet-like material including a step of raising a sheet by supplying a sheet obtained by applying a liquid to a sheet including a fiber entangled body and wet-buffing the sheet.

  The present invention also relates to a sheet-like material including a fiber-entangled body, at least one surface of which is covered with napped fibers made of ultrafine fibers, and the napped ultrafine fibers are uniformly oriented.

  Conventionally, various types of sheet-like materials have been studied by applying ultrafine fiber ultrafine technology to form a sheet-like material and raising it by raising treatment or the like.

  In the field of raising treatment, an apparatus for raising a fabric by dry buffing using sandpaper, a brush, a grindstone and a needle cloth is well known.

  On the other hand, in order to prevent the fabric from having heat and cutting the fiber in the raising step, an apparatus for buffing the fabric against the rotating grindstone with water pressure has been proposed (see Patent Document 1). However, in this proposal, there is no proposal to arrange the raised fibers in the same manner, and there is a description that the surface state is like a lotus leaf or a peach fruit. In this proposal, thick fibers such as cotton are targeted, and no proposal has been made for raising ultrafine fibers. Furthermore, since the fabric is pressed against the rotating grindstone with water pressure, the moisture content of the fabric to be raised cannot be adjusted, and since the moisture content is always excessive, the raising state cannot be strictly controlled. . Moreover, in this proposal, although the fiber is cut by heat, the size of the fluff is uniform, as described in the description that it has a uniform fluff. The act of being physically disconnected is aggressive. That is, it can be seen that the water pressure is strongly brushed and scraped off.

  Separately, a raised sheet made of ultrafine fibers of 1.5 dtex or less has been proposed (see Patent Document 2). There are proposals for dry buffing and wet buffing as raising methods, but as various raising methods are proposed, any proposal may be raised, and all examples are dry buffing. However, only wet buffing is listed, and there is no proposal to arrange the raised fibers in the same manner nor to propose an important buffing condition for wet buffing of ultrafine fibers.

  In the field of artificial leather, as an abrasive cloth that can be textured with high precision and few scratch defects, a napped abrasive cloth having an average single fiber fineness of 0.0001 to 0.01 dtex has been proposed. (See Patent Document 3). This proposal defines a state in which ultrafine fibers are uniformly arranged, and is characterized in that the linear density is not less than 30/100 μm width and not more than 1000/100 μm width. There are only proposals to reduce the number of buffs and sandpaper count, and there is no description of wet buffing that is important for raising ultrafine fibers with an average single fiber fineness of 0.0001 to 0.01 dtex. The surface has superfine fibers stuck together in a bundle, and the actual linear density does not achieve the above.

Furthermore, as a method of dispersing nanofibers on the surface, there is a proposal of an abrasive cloth having ultrafine fibers with a single fiber fineness of 1 × 10 ^{−8 to} 1.4 × 10 ⁻³ dtex (see Patent Document 4). In this case, ultrafine fibers are generated by dissolving and removing the readily soluble polymer from the composite fibers after raising the fibers. That is, in this proposal, the conventional buffing (dry buffing) cannot directly raise nanofibers, and there is almost no example of wet buffing, so raising the ultrafine fibers has been a problem.

JP-A-6-123060 JP 2000-21280 A JP 2007-54910 A JP 2007-144614 A

  Accordingly, in view of the actual state of the prior art described above, an object of the present invention is to provide a sheet-like material having an elegant surface state with an extremely dense surface touch by obtaining a raised surface in which ultrafine fibers are arranged extremely densely, and a method for producing the sheet-like material. There is to do.

  The present invention is intended to solve the above-described problem, and the method for producing a sheet-like material of the present invention includes a fiber entangled body mainly composed of ultrafine fibers having an average single fiber diameter of 0.01 to 8 μm. 10 to 300% by mass of liquid with respect to the mass of the sheet is supplied to the sheet, and the obtained sheet is supplied to the baffle, and is directly opposed to the baffle from the opposite side of the baffle through the sheet. It is a method for producing a sheet-like product, comprising a step of wet buffing a surface of the sheet that contacts the baffle without applying an external force and raising one surface of the sheet.

  According to the preferable aspect of the manufacturing method of the sheet-like material of this invention, it is wet-buffing processing in the state which provided 30-250 mass% of liquid with respect to the mass of the said sheet | seat.

  According to the preferable aspect of the manufacturing method of the sheet-like material of this invention, the liquid provided to the said sheet | seat is a viscosity of 20 mPa * s or less.

  According to a preferred embodiment of the method for producing a sheet-like product of the present invention, the fiber orientation ratio in the horizontal direction of the ultrafine fibers arranged in the vertical direction on at least one side of the napped surface subjected to the wet buffing treatment is set to 40 to 95%. It is.

  According to a preferred embodiment of the method for producing a sheet-like product of the present invention, the napped coverage of the napped surface in which the fiber orientation ratio in the horizontal direction of the ultrafine fibers arranged in the vertical direction is 40 to 95% is 40 to 100%. It is to masquerade.

  According to a preferred embodiment of the method for producing a sheet-like material of the present invention, in the ultrafine fiber with the raised surface having a fiber orientation ratio in the horizontal direction of the ultrafine fiber arranged in the vertical direction of 40 to 95%, The ratio of the fiber tip deformed to 120 to 300% of the fiber diameter is made 50% or less.

  According to the preferable aspect of the manufacturing method of the sheet-like material of this invention, the thickness of the napped layer in the at least one surface of the said napped surface which carried out the wet buffing process is 0.20 mm or less.

  The sheet-like material of the present invention is a sheet-like material comprising a fiber entangled body mainly composed of ultrafine fibers having an average single fiber diameter of 0.01 to 8 μm, and one or both surfaces of the sheet-like material are napped. The sheet-like material is characterized in that the fiber orientation ratio in the horizontal direction of the ultrafine fibers arranged in the vertical direction on at least one side of the raised surfaces is 40 to 95%.

  According to the preferable aspect of the sheet-like material of the present invention, the napped coverage of the raised surface in which the fiber orientation ratio in the horizontal direction of the ultrafine fibers arranged in the vertical direction is 40 to 95% is 40 to 100%. .

  According to a preferred aspect of the sheet-like material of the present invention, in the raised fiber having a raised surface in which the fiber orientation ratio in the horizontal direction of the ultrafine fibers arranged in the vertical direction is 40 to 95%, The ratio at which the tip is deformed to 120 to 300% of the fiber diameter is 50% or less.

  According to a preferred embodiment of the sheet-like material of the present invention, the polymer-like elastic material is contained in the sheet-like material, and the weight thereof is 10 to 60% by mass with respect to the mass of the fiber.

  According to the preferable aspect of the sheet-like material of the present invention, the thickness of the raised layer on at least one side of the raised surface is 0.20 mm or less.

  According to the method for producing a sheet-like product of the present invention, it is possible to arrange the ultrafine fibers extremely densely. In particular, it is possible to perform a napping process in which the surface state rich in napping and the deformation of the tip of the ultrafine fiber are suppressed as much as possible.

  In addition, according to the present invention, a sheet-like product having an elegant surface state can be obtained with a very fine surface touch by arranging the ultrafine fibers very densely. In particular, in a napped-rich surface state, the surface becomes an elegant and glossy surface and a smooth surface. In particular, in the case of napped fibers having ultrafine fibers in which the deformation of the tips of the ultrafine fibers is suppressed as much as possible, it is superior in the uniformity of the surface appearance and the uniformity of the surface touch, and used as a polishing cloth for polishing and / or cleaning. In some cases, it is superior in suppressing scratches.

  The sheet-like material of the present invention comprises a fiber entangled body mainly composed of ultrafine fibers having an average single fiber diameter of 0.01 to 8 μm, and one or both surfaces of the sheet-like material are constituted by napped surfaces, It is a sheet-like material in which the fiber orientation ratio in the horizontal direction of the ultrafine fibers arranged in the vertical direction on at least one side of the surface is 40 to 95%.

  In the present invention, it is important that the average single fiber diameter of the ultrafine fibers is 0.01 to 8 μm.

  The average single fiber diameter is 8 μm or less, preferably 5 μm or less, and more preferably 3 μm or less because the fiber has excellent denseness and strong fiber gripping force. The excellent denseness is advantageous when making the surface rich with napping. The same applies to the surface touch, and it is possible to obtain a sheet-like material with a texture different from that of conventional ultra-fine fibers, especially when used as an abrasive cloth, achieving a high-precision finish. A polishing cloth that can be used is obtained. The same applies to the glossiness. In particular, when it is used as a dyed artificial leather, the number of uniformly aligned fibers is increased, and a glossy sheet can be obtained. The same applies to the fiber orientation rate, and the fiber orientation rate, which means denseness, tends to increase. When the average single fiber diameter is larger than 8 μm, the fiber orientation ratio is less than 40%, and the surface appearance of a conventional artificial leather with poor denseness and glossiness is obtained.

  Moreover, when the average single fiber diameter is 0.01 μm or more, preferably 0.2 μm or more, more preferably 1 μm or more, a sheet-like product having high single fiber strength and rigidity is obtained, especially when used as an abrasive cloth. Expresses high grinding performance. If the average single fiber diameter is less than 0.01 μm, the ultrafine fiber aggregates are aggregated and difficult to open, and the raised surface quality is significantly reduced because it is not raised, and the desired surface touch cannot be obtained. When used as a cause of scratches.

  Regarding the uniformity of the single fiber diameter, the fiber diameter CV value of the ultrafine fiber is preferably 40% or less, more preferably 30% or less. The fiber diameter CV value here is the percentage (%) of the value obtained by measuring the average single fiber diameter of any 100 ultrafine fibers, calculating the average value and standard deviation, and dividing the standard deviation by the average value. The smaller this value is, the more uniform it is. By setting the fiber diameter CV value to 40% or less, it is possible to obtain a sheet-like material with uniform napping, an elegant surface appearance and an extremely soft surface touch. In particular, a polishing cloth can be polished with high accuracy by a uniform pressing force and abrasive dispersibility.

  Further, when the fiber diameter CV value is smaller than 0.1%, the surface appearance becomes artificial like instead of natural like because the uniformity is excessive, resulting in poor elegance. In particular, in the polishing cloth, when the uniformity is excessive, a friction due to frictional heat is caused by an increase in friction during polishing. A more preferable fiber diameter CV value is 0.5% to 10%.

  Examples of the polymer forming the ultrafine fiber used in the present invention include polyesters such as polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate and polylactic acid, polyamides such as 6-nylon and 66-nylon, acrylic, polyethylene, and polypropylene. And thermoplastic resins that can be melt-spun such as thermoplastic cellulose. Among these, polyester is preferably used from the viewpoint of strength, dimensional stability, and light resistance.

  Moreover, it is a preferable aspect that it is the fiber obtained from a recycling raw material or a plant-derived raw material from a viewpoint of environmental consideration. Polycondensation polymers typified by polyesters and polyamides constituting fibers often have high melting points and are excellent in heat resistance against heat, and are preferably used. In particular, the fibers made of polyamides have particularly good compatibility with the slurry liquid, have excellent retention and dispersibility of the abrasive grains in the slurry liquid, and polish without damaging non-polished materials. In addition, since it has excellent flexibility and low contact resistance with an object to be polished, it is suitably used for fine polishing. Further, the ultrafine fibers can be configured by mixing fibers of different materials.

  In addition, the polymer constituting the ultrafine fibers may be copolymerized with other components, and may contain additives such as particles, flame retardants, and antistatic agents.

  As the cross-sectional shape of the ultrafine fiber, for example, a polygon such as a circle, an ellipse, a flat shape, and a triangle, a fan, a cross, Y, H, X, W, C, and a π type can be used.

  It is a preferable aspect that the ultrafine fibers constituting the fiber entangled body take the form of an ultrafine fiber bundle. As a form of the ultrafine fiber bundle, the ultrafine fibers may be somewhat separated from each other, and may be partially bonded or agglomerated in some cases.

  The fiber entangled body used in the sheet-like product of the present invention may be either a short fiber entangled body or a long fiber entangled body, but a short fiber entangled body is preferably used in terms of compressibility and quality.

  As a short fiber entangled body used in the sheet-like material of the present invention, a short fiber nonwoven fabric obtained by applying a needle punch or a water jet punch after forming a laminated web using a card and a cross wrapper, A long fiber nonwoven fabric obtained from a spunbond method or a melt blow method, a nonwoven fabric obtained by a papermaking method, or the like can be appropriately employed. As the fiber entanglement, a woven or knitted fabric may be used, but it is necessary to adjust the number of fibers in the vertical direction from the viewpoint of the fiber orientation rate and napped coverage, so that there is a nonwoven fabric that is advantageous not only in the vertical direction but also in the thickness direction. More preferably used.

  Among these, the short fiber nonwoven fabric and the spunbond nonwoven fabric can obtain the form of the ultrafine fiber bundle as described later by needle punching. The fiber length of the short fiber in the short fiber nonwoven fabric is preferably 25 to 90 mm. By setting the fiber length to 25 mm or more, a sheet-like material having excellent abrasion resistance can be obtained by entanglement. Moreover, by setting the fiber length to 90 mm or less, it is possible to obtain a sheet-like material excellent in compression characteristics and surface quality of the sheet-like material. The fiber length is more preferably 30 to 80 mm.

  The fiber entangled body used in the present invention can include a reinforcing layer for the purpose of improving the strength. As the reinforcing layer, woven fabrics, knitted fabrics, nonwoven fabrics (including paper), and film-like materials such as plastic films and metal thin film sheets can be employed. In the case of a woven or knitted fabric in which the reinforcing layer is composed of fibers, the average single fiber diameter of the fibers is preferably about 0.1 to 20 μm.

  In the sheet-like material of the present invention, one or both sides of the sheet-like material are constituted by raised surfaces, and the fiber orientation ratio in the horizontal direction of the ultrafine fibers arranged in the vertical direction on at least one surface of the raised surfaces is 40 to 95%. It is important that

  By setting the fiber orientation rate to 40% or more, preferably 50% or more, more preferably 60% or more, a dense napping, an elegant surface appearance, and a conventional sheet-like material made of ultrafine fibers Sheet-like materials having different textures can be obtained. In particular, the polishing cloth is a preferable mode because the wiping performance is improved. In particular, when wet buffing is performed on artificial leather containing dyed polymer elastic bodies, the polymer elastic bodies (irritations) that have a color difference from the fibers are hidden by densely orienting the fibers, which makes the appearance more elegant and preferable. It is. When the fiber orientation ratio exceeds 95%, it becomes impossible to recognize the touch feeling of each ultrafine fiber, and the surface touch feels rough. In particular, in the polishing cloth, the degree of freedom of the space between the ultrafine fibers decreases, and the slurry cannot be dispersed, which causes scratches. Further, in the production of a sheet-like product, the openability of the ultrafine fibers is significantly reduced. When the fiber orientation ratio is less than 40%, the surface appearance of a conventional artificial leather with poor denseness and glossiness is obtained.

In the present invention, at least one surface thereof is a raised surface composed of the above-mentioned ultrafine fibers, and the degree of orientation of the ultrafine fibers on the raised surface is defined as the fiber orientation rate in the horizontal direction of the fibers arranged in the vertical direction. In other words, the napped direction in which the degree of orientation is large is the vertical direction, and the orthogonal direction is the horizontal direction. Then, using the surface of the sheet-like material as an observation surface, 30 images of the sheet-like material with an observation magnification of 5000 times are taken with a scanning electron microscope (SEM). From the photographed image, avoid a portion where a polymer elastic body such as polyurethane is exposed on the surface and no ultrafine fiber is present, or a portion where a large hole is formed by a needle punch or the like, and a reference line of 100 μm is aligned in the horizontal direction. Draw a place. Lines in the horizontal direction of the fibers arranged in the vertical direction by calculating the average value of n number 30 by measuring the number of ultra fine fibers having an acute angle of 60 ° or more intersecting with the reference line in the vertical direction. Density. From the linear density and theoretical linear density (100 μm ÷ single fiber diameter), the fiber orientation ratio (%) is calculated by the following formula.
・ Fiber orientation ratio (%) = Linear density (book) ÷ Theoretical linear density (book)
The sheet-like material of the present invention preferably has a napped surface coverage of 40 to 95% of the fiber orientation ratio in the horizontal direction of the ultrafine fibers arranged in the vertical direction of 40 to 100%, more preferably 45. ~ 95%. When the napping coverage is less than 40%, there are fibers that are not napped, and the surface quality becomes non-uniform. In particular, in the case of artificial leather containing a dyed polymer elastic body, the non-raised portion is severely irritated and cannot be said to have an elegant appearance quality. Further, since the wiping performance is lowered, the performance is inferior particularly when an abrasive cloth is used.

The napped coverage is the above-described napped surface of the ultrafine fibers arranged in the vertical direction having a fiber orientation ratio of 40 to 95%, so that the presence of napped fibers can be seen by a scanning electron microscope (SEM). The magnification was increased to 30 times to 70 times, and the ratio of the total area of the napped portions per total area of 4 mm ² was calculated using image analysis software, and was defined as the napped coverage. The ratio of the total area can be calculated by binarizing the captured SEM image using the image analysis software ImageJ with the raised portion and the non-raised portion set to the threshold value 100. In the calculation of the napped coverage, if a substance that is not napped is calculated as napped and greatly affects the napped coverage, the image is manually edited and the portion is calculated as a non-napped portion.

  Image analysis software ImageJ is exemplified as the image analysis system. However, the image analysis system is not limited to image analysis software ImageJ as long as the image analysis system includes image processing software having a function of calculating the area ratio of a prescribed pixel. . The image processing software ImageJ is a common software and was developed by the National Institutes of Health. The image processing software ImageJ has a function of specifying a necessary region for the captured image and performing pixel analysis.

  The sheet-like material of the present invention is a fiber with a raised surface having a fiber orientation ratio in the horizontal direction of the ultrafine fibers arranged in the vertical direction of 40 to 95%, and the tip of the ultrafine fiber is 120 to 300 with respect to the fiber diameter. It may be preferred that the ratio of deformation to% is 50% or less. When the deformed ratio is 50% or less, a smooth touch is obtained, and the fiber orientation rate tends to be small. Further, when used as an abrasive cloth, it is advantageous in terms of scratches. This is also a preferred embodiment from the viewpoint of uniformity of surface appearance and denseness. Napped hair obtained only by wet buffing has a deformed ratio of 50% or less. When wet buffing is performed on a dry buffed sheet, the wet buffing cuts the fibers deformed by the dry buffing, but the deformation disappears, but the deformed fibers remain in a portion where the fibers are just arranged.

  In the sheet-like material of the present invention, the thickness of the raised layer on at least one of the raised surfaces may be preferably 0.20 mm or less. The raised layer has a lower density than the non-raised layer and is weak in strength. By setting the thickness of the raised layer to 0.20 mm or less, a sufficient strength is exhibited in applications where a high strength sheet is required. When the napped layer is 0.001 mm or less, the napped layer is weak and is broken by a force such as abrasion.

  In the sheet-like material of the present invention, a large number of gaps of several nanometers to 500 nm are created between single fibers or intertwined fibers, and thus may exhibit specific properties such as a porous material, such as a filter. It can also be used as an application.

  The sheet-like material of the present invention preferably contains 10 to 60% by mass of a polymer elastic body with respect to the mass of the ultrafine fibers of the fiber entanglement. By including at least 10% by mass of the polymer elastic body with respect to the mass of the ultrafine fibers, it becomes possible to impart an appropriate compression property to the sheet-like material. When the mass of the polymer elastic body is more than 60% by mass, the fiber opening property in the napping process is poor, and the flexibility of the sheet-like material is lowered. Furthermore, when a sheet-like material is used after being dyed, there is a difference in color tone between the fiber of the fiber entangled body after dyeing and the polymer elastic body. In terms of environmental considerations, it is not preferable to add a large amount of a polymer elastic body because the amount of organic substances used in the production process increases, and a smaller amount of the polymer elastic body can be obtained from recycled materials and plant-derived materials. When fibers are used, it is easy to recover and discard. In the case of the polishing cloth, since the surface is made only of fibers because the polymer elastic body is not included, scratch defects caused by the polymer elastic body scraping the object to be polished are reduced. A more preferable range of the mass of the polymer elastic body is 15 to 55 mass%.

  In the above-mentioned polymer elastic body, if necessary, pigments such as carbon black, dyes, antifungal agents and antioxidants, UV absorbers, light stabilizers such as light stabilizers, flame retardants, penetrants and lubricants, Antiblocking agents such as silica and titanium oxide, water repellents, viscosity modifiers, surfactants such as antistatic agents, antifoaming agents such as silicone, fillers such as cellulose, and coagulation regulators, and silica and titanium oxide Inorganic particles such as can be contained.

  Examples of the polymer elastic body used in the present invention include polyurethane elastomers, polyureas, polyacrylic acid, ethylene / vinyl acetate elastomers and acrylonitrile / butadiene elastomers and styrene / butadiene elastomers, polyvinyl alcohol, and polyethylene glycol. From the viewpoints of properties and compression characteristics, polyurethane elastomers are preferably used. The polymer elastic body can contain a plurality of polymer elastic bodies.

  Examples of the polyurethane elastomer particularly preferably used in the present invention include polyurethane and polyurethane / polyurea elastomer.

  As the polyurethane elastomer used in the present invention, any of a solvent-based polyurethane elastomer and a water-dispersed polyurethane elastomer can be used.

  As the polyurethane elastomer used in the present invention, a polyurethane elastomer obtained by a reaction of a polymer diol, an organic diisocyanate and a chain extender is preferably used.

  As the polymer diol, for example, a polycarbonate diol, a polyester diol, a polyether diol, a silicone diol, and a fluorine diol can be employed, and a copolymer combining these can also be used. Among these, from the viewpoint of hydrolysis resistance, it is preferable to use a polycarbonate diol and a polyether diol.

  The polycarbonate-based diol can be produced by transesterification of alkylene glycol and carbonate, or reaction of phosgene or chloroformate with alkylene glycol.

  Examples of the alkylene glycol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, 1,10-decanediol, and the like. Linear alkylene glycol, and branched alkylene glycols such as neopentyl glycol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol and 2-methyl-1,8-octanediol Alicyclic diols such as 1,4-cyclohexanediol, aromatic diols such as bisphenol A, glycerin, trimethylolpropane, and pentaerythritol. In the present invention, both polycarbonate-based diols obtained from individual alkylene glycols and copolymerized polycarbonate-based diols obtained from two or more types of alkylene glycols can be employed.

  Examples of the polyester diol include polyester diols obtained by condensing various low molecular weight polyols and polybasic acids.

  Examples of the low molecular weight polyol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, and 2,2-dimethyl-1,3-propane. Diol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,8-octanediol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, cyclohexane-1,4-diol, and One kind or two or more kinds selected from cyclohexane-1,4-dimethanol can be used.

  Further, addition products obtained by adding various alkylene oxides to bisphenol A can also be used.

  Polybasic acids include, for example, succinic acid, maleic acid, adipic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, and hexahydro One kind or two or more kinds selected from isophthalic acid can be mentioned.

  Examples of the polyether-based diol used in the present invention include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and copolymer diols obtained by combining them.

  The number average molecular weight of the polymer diol is preferably in the range of 500 to 4000 when the molecular weight of the polyurethane-based elastomer is constant. By making the number average molecular weight preferably 500 or more, more preferably 1500 or more, it is possible to prevent the sheet-like material from becoming hard. Moreover, the intensity | strength as a polyurethane-type elastomer is maintainable by making a number average molecular weight into 4000 or less, More preferably, 3000 or less.

  Examples of the organic diisocyanate used in the present invention include aliphatic diisocyanates such as hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate and xylylene diisocyanate, and aromatic diisocyanates such as diphenylmethane diisocyanate and tolylene diisocyanate. These can also be used in combination. Among these, aliphatic diisocyanates such as hexamethylene diisocyanate, dicyclohexylmethane diisocyanate and isophorone diisocyanate are preferably used from the viewpoint of light resistance.

  As the chain extender, amine chain extenders such as ethylenediamine and methylenebisaniline, and diol chain extenders such as ethylene glycol can be preferably used. Moreover, the polyamine obtained by making polyisocyanate and water react can also be used as a chain extender.

  The polyurethane used in the present invention can be used in combination with a crosslinking agent for the purpose of improving water resistance, abrasion resistance, hydrolysis resistance and the like. The cross-linking agent may be an external cross-linking agent added as a third component to the polyurethane-based elastomer, or an internal cross-linking agent that introduces a reaction point that becomes a cross-linked structure in advance in the polyurethane molecular structure. From the viewpoint that the cross-linking points can be formed more uniformly in the polyurethane molecular structure and the reduction in flexibility can be reduced, it is preferable to use an internal cross-linking agent.

  As the crosslinking agent, compounds having an isocyanate group, an oxazoline group, a carbodiimide group, an epoxy group, a melamine resin, a silanol group, and the like can be used.

  In addition, when the polyurethane elastomer used in the present invention is a water-dispersed polyurethane elastomer, it is a preferred embodiment that has a hydrophilic group in the molecular structure. By including a hydrophilic group in the molecular structure, dispersion and stability as a water-dispersed polyurethane elastomer can be improved.

  Examples of the hydrophilic group include any one of a cationic group such as a quaternary amine salt, a combination of an anionic hydrophilic group such as a sulfonate and a carboxylate, and a combination of an anionic and nonionic hydrophilic group. Hydrophilic groups can also be employed.

  Of these, nonionic hydrophilic groups that are free from yellowing caused by light and harmful effects caused by a neutralizing agent are particularly preferably used. That is, in the case of an anionic hydrophilic group, a neutralizing agent is required. For example, the neutralizing agent is a tertiary amine such as ammonia, triethylamine, triethanolamine, triisopropanolamine, trimethylamine and dimethylethanolamine. In some cases, amines are generated and volatilized by heat during film formation or drying, and released outside the system. For this reason, in order to suppress the release of air and the deterioration of the working environment, it is essential to introduce a device for recovering volatile amines.

  In addition, when the amine does not volatilize by heating and remains in the final product sheet, it may be discharged to the environment when the product is incinerated. On the other hand, in the case of a nonionic hydrophilic group, since no neutralizing agent is used, it is not necessary to introduce an amine recovery device, and there is no fear of remaining amine in the sheet. In addition, when the neutralizing agent is an alkali metal such as sodium hydroxide, potassium hydroxide and calcium hydroxide, or a hydroxide of an alkaline earth metal, the polyurethane part becomes alkaline when wetted with water, In the case of a nonionic hydrophilic group, since a neutralizing agent is not used, there is no need to worry about degradation due to hydrolysis of the polyurethane elastomer.

The apparent density of the sheet-like material of the present invention is preferably 0.10 to 0.80 g / cm ³ , more preferably 0.20 to 0.70 g / cm ² . When the apparent density is 0.10 g / cm ³ or more, the denseness and mechanical properties of the sheet-like material are good, and when it is 0.80 g / cm ³ or less, it is possible to avoid the texture becoming hard.

  The thickness of the sheet material is preferably 0.1 to 7 mm. By setting the thickness to 0.1 mm or more, preferably 0.3 mm or more, the sheet form has excellent form stability and dimensional stability. On the other hand, when the thickness is 7 mm or less, more preferably 5 mm or less, the sheet-like product is excellent in moldability.

  Next, a method for producing the sheet-like material of the present invention will be described.

  As a means for obtaining a nonwoven fabric such as a fiber entangled body in which the ultrafine fiber bundle used in the present invention is entangled, it is a preferable aspect to use an ultrafine fiber generating fiber such as a sea-island fiber. Although it is difficult to manufacture a nonwoven fabric such as a fiber entangled body directly from an ultrafine fiber, a fiber entangled body is manufactured from an ultrafine fiber generating fiber, and an ultrafine fiber generating fiber such as a sea-island fiber in the fiber entangled fiber is manufactured. By generating fibers, it is possible to obtain a fiber entangled body in which ultrafine fiber bundles are entangled.

  For sea-island type fibers, sea-island type composite fibers that use a sea-island type composite base to spun two components of the sea component and the island component, and mixed spinning that mixes and spins the two components of the sea component and the island component are spun. Examples thereof include fibers. Among these sea-island type fibers, it is possible to obtain ultrafine fibers controlled with high accuracy, and to obtain a sufficiently long ultrafine fiber, which also contributes to the strength of the nonwoven fabric and the sheet-like material having the nonwoven fabric. From the viewpoint, sea-island type composite fibers are preferably used.

  Examples of the sea component of the sea-island fiber include polyethylene, polypropylene, polystyrene, copolymer polyester obtained by copolymerizing sodium sulfoisophthalate, polyethylene glycol, and the like, polylactic acid, and PVA.

  The fiber ultrafine treatment (sea removal treatment) of the sea-island fiber can be performed by immersing the sea-island fiber in a solvent and squeezing the solution. As the solvent for dissolving the sea component, when the sea component is polyethylene, polypropylene, or polystyrene, an organic solvent such as toluene or trichloroethylene is used. Further, when the sea component is a copolyester or polylactic acid, an alkaline aqueous solution such as sodium hydroxide is used.

  In addition, for the fiber ultrafine treatment, apparatuses such as a continuous dyeing machine, a vibro-washer type seawater removal machine, a liquid dyeing machine, a Wins dyeing machine, and a jigger dyeing machine can be used.

  The sea component can be dissolved and removed at any timing before the impregnation with the polymer elastic body, after the impregnation, and after the raising treatment. If the seawater treatment is performed before application of the polymer elastic body, the polymer elastic body is in close contact with the ultrafine fibers, and the ultrafine fibers can be strongly held, so that the wear resistance of the sheet-like material is improved. On the other hand, when seawater removal treatment is performed after the polymer elastic body is applied, voids are generated between the polymer elastic body and the ultrafine fibers due to the sea component being desealed. In addition, the compression property of the sheet-like material is improved.

  In the present invention, the number of fibers in the ultrafine fiber bundle is preferably 10 to 9000 fibers / bundle, more preferably 10 to 4000 fibers / bundle. When the number of fibers is less than 10 / bundle, the fineness of the ultrafine fibers is poor, and for example, mechanical properties such as wear tend to be reduced. Moreover, when there are more than 9000 fibers / bundle, the openability at the time of napping falls, and there exists a tendency for the fiber distribution of a napped surface to become non-uniform | heterogenous.

  From the viewpoint of fiber density, the degree of fiber density in the ultrafine fiber bundle is preferably 30 to 1000, more preferably 50 to 700. The degree of fiber density is calculated by (number of fibers in the ultrafine fiber bundle) × (single fiber diameter) and is an index of the size of the ultrafine fiber bundle. Thus, by setting the fiber density in the ultrafine fiber bundle to 30 to 1000, the processing operability when making the fiber entangled body is good, and the denseness of the fiber bundle is improved.

  As a method for obtaining the fiber entangled body used in the present invention, a method in which the fiber web is entangled with a needle punch or a water jet punch, a spun bond method, a melt blow method, a paper making method, or the like can be employed. Among them, a method that undergoes a treatment such as a needle punch or a water jet punch is preferably used in order to obtain an ultrafine fiber bundle as described above.

  In the needle used for the needle punching process, the number of needle barbs (cuts) is preferably 1 to 9. By using one or more needle barbs, efficient fiber entanglement becomes possible. On the other hand, fiber damage can be suppressed by using 9 or less needle barbs.

The number of punching is preferably 1000 to 6000 / cm ² . By setting the number of punching to 1000 pieces / cm ² or more, denseness can be obtained and high-precision finishing can be obtained. On the other hand, by setting the number of punching to 6000 / cm ² or less, deterioration of workability, fiber damage, and strength reduction can be prevented. A more preferable punching number is 1500 to 4000 / cm ² .

  Moreover, when performing a water jet punch process, it is a preferable aspect that water is performed in a columnar flow state. Specifically, it is a preferred embodiment that water is ejected from a nozzle having a diameter of 0.05 to 1.0 mm at a pressure of 2 to 60 MPa.

It is preferable that the apparent density of the fiber entangled body composed of the ultrafine fiber generating fiber after the needle punching process or the water jet punching process is 0.15 to 0.40 g / cm ³ . By setting the apparent density to 0.15 g / cm ³ or more, a fiber entangled body having excellent shape stability and dimensional stability can be obtained. On the other hand, when the apparent density is 0.40 g / cm ³ or less, preferably 0.30 g / cm ³ or less, a sufficient space for applying the elastic polymer can be maintained between the fibers.

  The fiber entangled body composed of the ultrafine fiber-generating fibers thus obtained is preferably subjected to heat shrinkage treatment with dry heat or wet heat, or both from the viewpoint of densification, and further densified. It is. Further, the fiber entangled body can be compressed in the thickness direction by calendaring or the like.

  In addition, in order to obtain denseness and uniformity of the fiber distribution on the surface of the sheet-like material, the polymer elastic body is a fiber bundle of ultrafine fibers such as a nonwoven fabric in which a fiber bundle of ultrafine fibers is entangled. It is a preferred embodiment that it does not substantially exist inside. If the polymer elastic body exists inside the fiber bundle, the polymer elastic body is adhered to each ultrafine fiber, so that the opening property during the buffing process is poor.

As a method for obtaining a form in which the polymer elastic body does not substantially exist inside the fiber bundle of ultrafine fibers, for example, the polymer elastic body is used as a solution,
(1) A solvent that does not dissolve the elastic component of the sea-island fiber after impregnating and solidifying the above-mentioned polymer elastic body solution into a fiber entangled body composed of ultra-fine fiber-generating sea-island fiber To dissolve and remove with
(2) A fiber entangled body composed of ultra-fine fiber-generating sea-island fibers is provided with polyvinyl alcohol having a saponification degree of preferably 80% or more to protect most of the surroundings of the sea-island fibers. A method in which the sea component is dissolved and removed with a solvent that does not dissolve polyvinyl alcohol, and then the polymer elastic body solution is impregnated and solidified, and then the polyvinyl alcohol is removed is preferably used.

  As the polyvinyl alcohol, polyvinyl alcohol having a saponification degree of 80% or more is preferably used.

  When a polyurethane-based elastomer liquid is impregnated into a fiber entangled body and solidified, if the polyurethane-based elastomer is a solvent-based polyurethane-based elastomer, it can be coagulated by dry heat coagulation, wet coagulation or a combination thereof. it can. In the case of a water-dispersed polyurethane elastomer, the polyurethane elastomer can be coagulated by dry heat coagulation, wet heat coagulation, wet coagulation, or a combination thereof.

  When the polyurethane elastomer is solvent-based, wet coagulation in which it is solidified by immersion in water is preferably used. When the polyurethane elastomer is water-dispersed polyurethane, wet heat coagulation is preferably used. When the polyurethane elastomer is water-dispersed, it is preferably used to exhibit heat-sensitive coagulation.

  In water-dispersible polyurethane-based elastomers, if they do not exhibit heat-sensitive coagulation, the polyurethane-based elastomer liquid undergoes a migration phenomenon that concentrates on the surface layer of the fiber entangled body during dry coagulation, and a sheet-like material containing the polyurethane-based elastomer Tend to harden. Here, the heat-sensitive coagulation property refers to the property that when the polyurethane elastomer liquid is heated, the fluidity of the polyurethane elastomer liquid decreases and solidifies when reaching a certain temperature (thermal coagulation temperature).

  The heat-sensitive coagulation temperature of the water-dispersed polyurethane elastomer is preferably 40 to 90 ° C. By setting the heat-sensitive coagulation temperature to 40 ° C. or higher, stability during storage of the polyurethane elastomer liquid is improved, and adhesion of the polyurethane elastomer to the machine during operation can be suppressed. Moreover, the migration phenomenon of the polyurethane-type elastomer in a fiber entanglement body can be suppressed by making a thermal coagulation temperature 90 degrees C or less, and it can make it unevenly distribute inside.

  In order to set the heat-sensitive coagulation temperature as described above, a heat-sensitive coagulant can be appropriately added. Examples of heat-sensitive coagulants include inorganic salts such as sodium sulfate, magnesium sulfate, calcium sulfate and calcium chloride, and radical reactions such as sodium persulfate, potassium persulfate, ammonium persulfate, azobisisobutyronitrile and benzoyl peroxide. Initiators are mentioned.

  The temperature of wet coagulation is not particularly limited in the case of a solvent-based polyurethane elastomer. In the case of a water-dispersed polyurethane elastomer, it may be at least the heat-sensitive coagulation temperature of the polyurethane elastomer, and for example, a temperature of 40 to 200 ° C. is preferable. By setting the wet heat coagulation temperature to 40 ° C. or higher, more preferably 60 ° C. or higher, the time to solidification of the polyurethane elastomer can be shortened to further suppress the migration phenomenon. On the other hand, by setting the wet heat coagulation temperature to 200 ° C. or lower, more preferably 160 ° C. or lower, it is possible to prevent thermal degradation of the polyurethane elastomer.

  Dividing the obtained polymer elastic body-provided sheet-like material into half or several sheets in the sheet thickness direction after imparting the polymer elastic body to the fiber entangled body is a preferable aspect with excellent production efficiency. The same applies when no polymer elastic body is applied.

  It is important that the sheet-like material of the present invention has napping on at least one surface of the sheet-like material.

  In the method for producing a sheet-like material of the present invention, the liquid is applied in an amount of 10 to 300% by mass with respect to the mass of the sheet, and the obtained sheet is supplied to the buffalo. It is important to include a step of wet buffing the surface of the sheet in contact with the baffle without applying an external force directly facing the baffle and raising one side of the sheet.

  If there is an external force that directly faces the buffalo, the amount of liquid applied will be outside the above range, and the sheet will be buffed in a compressed state. The fiber orientation rate becomes insufficient due to the movement of. Moreover, since the compressed part becomes the napped layer thickness as it is, the napped layer thickness is increased. As a result, it is close to general dry buffing, and the obtained sheet-like material is in a general napped state. The dry-type buffing treatment here can be performed by a method of grinding or rubbing the surface of the sheet using a sandpaper or a roll sander without making the sheet wet. In particular, by buffing the surface of the sheet using sandpaper, uniform and dense napping can be formed.

  On the other hand, in the method for producing a sheet-like product of the present invention, it is important to wet-buff the sheet-like product after the above-mentioned general napping treatment or not, or after dyeing. When combining various napping treatments, it is preferable to include wet buffing at the end.

  When wet buffing is performed after a general napping treatment, a part of the surface layer of the napped layer that is originally present is in a state obtained by wet buffing, depending on the grinding load of buffing. That is, the sheet-like material of the present invention can leave part of the napping obtained by a general napping treatment within the scope of the present invention. In the case of dyeing, wet buffing after dyeing is a more preferable embodiment in order to maintain the obtained surface state. A treatment for improving the fiber orientation rate with a brush or a heating roll after dyeing is known, but wet buffing allows a high orientation rate to give a gloss.

  In wet buffing, the liquid to be applied to the sheet is not particularly specified such as water or chemicals, but from the point of view of environmental considerations and cost, it can be removed by drying and water or water as a solvent. Is preferably used. When the viscosity of the liquid is high, the napped fibers are difficult to be evenly arranged, that is, the fiber orientation ratio is low. Therefore, the viscosity of the liquid is preferably 20 mPa · s or less. Preferably, it is 10 mPa · s or less. The viscosity is measured with a B-type viscometer. The quantity which provides a liquid is 10-300 mass% with respect to the mass of a sheet-like material. When the amount of the liquid is less than 10% by mass, the surface of the sheet to be buffed cannot be stably moistened, and when it exceeds 300% by mass, the resistance is large and the napping is not efficiently performed. By setting the amount of the liquid to preferably 30 to 250% by mass, more preferably 50 to 230% by mass, and still more preferably 100 to 200% by mass, napped fibers having a high fiber orientation rate can be stably obtained. In this way, the wet state prevents the ultrafine fibers from fusing with each other by buffing treatment, and also increases the spreadability, and the fiber orientation rate becomes a region that cannot be obtained by general buffing treatment. . In addition, there is an effect that the fiber is hardly cut and raised, and dry buffing is known to deform the fiber tip, but also has an effect of suppressing the deformation.

  Usually, the liquid applied to the sheet by wet buffing is dried and removed after wet buffing.

  It is also possible to suppress fusion and deformation by protecting the fibers with a silicone emulsion or the like and buffing in a dry state. However, in film-forming protection, if the amount applied is not excessive so that the protective layer is thick, the fusing effect is insufficient, and the drug remains excessively on the sheet even after buffing treatment, resulting in poor surface touch and high cost. It also affects the subsequent process.

  As a method for applying a liquid to the sheet, a known method such as coating or dipping can be used, but dipping is more preferably used because the wet unevenness of the entire sheet is reduced. Moreover, a fine surface without spots can be obtained by applying a liquid after applying the liquid. In order to adjust the amount of the liquid, it is a preferable aspect that the sheet can be stably adjusted using a nip roll after the sheet is once immersed in the liquid.

  Furthermore, in order to form the above-mentioned uniform ultrafine fiber napping on the surface of the sheet-like material, it is preferable to use sandpaper, and the sandpaper abrasive particle size, the baffle rotation speed, the sheet speed, and the sheet contact It is preferable to control the length within an appropriate range.

  In order to reduce the grinding load received by the sheet-like material in the buffing process, the number of buffing stages can be increased. The sandpaper count is preferably in the range of 120 to 600 according to JIS regulations. The buffalo speed is preferably 200 to 1500 m / min, more preferably 300 to 1000 m / min. The baffle speed is a peripheral speed calculated from the rotation speed and the peripheral length of the buffalo.

  The speed of the sheet supplied to the buffalo is preferably 0.1 m / min or more, more preferably 1.0 m / min or more from the viewpoint of productivity. 20 m / min or less is preferable from stability of a napped state, More preferably, it is 10 m / min or less, More preferably, it is 8 m / min or less. The baffle and sheet contact length in the buffing treatment is preferably 0.1 to 50 cm, more preferably 1 to 20 cm. The contact length of the sheet is the circumferential length of the baffle with which the sheet is in contact. If it is less than 0.1 cm, napping will be insufficient, and if it exceeds 50 cm, the length of the sheet that comes into contact with the heated bafrol is long, and the sheet itself is buffed with heat, so the effect of wet buffing is sufficient. I can't get it.

  By applying a lubricant such as silicone to the sheet before the wet buffing treatment, the surface of the ultrafine fibers is protected and the effect of suppressing fusion is exhibited, and the fiber opening property is also improved by the lubricating effect. In addition, applying an antistatic agent before the raising of the sheet is a preferable embodiment in order to make it difficult for the grinding powder generated from the sheet-like material to be deposited on the sandpaper by grinding. The liquid applied to the sheet by the wet buffing treatment can be a lubricant such as a silicone emulsion.

  The sheet-like material can be dyed depending on the application. As a method for dyeing a sheet-like material, it is preferable to use a liquid dyeing machine because the sheet-like material can be softened by simultaneously giving a stagnation effect. If the dyeing temperature of the sheet-like material is too high, the polymer elastic body may be deteriorated. On the other hand, if it is too low, the dyeing to the fiber becomes insufficient. In general, the dyeing temperature is preferably 80 to 150 ° C, more preferably 110 to 130 ° C.

  The dye can be selected according to the type of fiber constituting the sheet-like material. For example, disperse dyes can be used for polyester fibers, acidic dyes or metal-containing dyes can be used for polyamide fibers, and combinations thereof can be used.

  Moreover, it is also a preferable aspect to use a dyeing assistant when dyeing the sheet-like material. By using a dyeing assistant, the uniformity and reproducibility of dyeing can be improved. In addition, a finishing treatment using a softening agent such as silicone, an antistatic agent, a water repellent, a flame retardant, a light proofing agent, and an antibacterial agent can be performed in the same bath or after dyeing.

  The sheet-like material of the present invention includes furniture, chairs and wall materials, interior materials having a very elegant appearance as a skin material such as seats, ceilings and interiors in vehicles such as automobiles, trains and aircraft, shirts, jackets, Industry such as casual shoes, sports shoes, uppers and trims for shoes such as men's shoes and women's shoes, bags, belts, wallets, etc., clothing materials used for some of them, wiping cloths, filters and CD curtains It can be suitably used as a material for use.

  The sheet-like material of the present invention is superior in peel strength because the fibers are densely and uniformly arranged. When a coated layer is formed on the surface of the sheet-like material to produce an artificial leather with silver or a polishing pad, It can also be used. As a method for forming a coating layer or an undercoat layer for making an artificial leather with silver, there are a dry surface forming method, a direct coating method, etc., and various conventionally known methods can be adopted and are particularly limited. is not. For example, the method using apparatuses, such as a reverse roll coater, a spray coater, a roll coater, a gravure coater, a kiss roll coater, a knife coater, a comma coater, can be mentioned. The thickness of each layer can be appropriately set according to the application. The preferred thickness is 10 to 1000 μm, more preferably 50 to 800 μm.

  The resin used for the coating layer is most preferably polyurethane. Other resins can be appropriately mixed and used for the resin. In recent years, since durability is required for many applications, it is preferable to use a polyurethane having excellent durability such as polyether or polycarbonate. From the viewpoint of wear resistance, silicone-modified polyurethane is preferably used. For the same reason, the polyurethane resin can be used by containing silicone oil or a solid silicone compound.

  From the viewpoint of environmental load, it is preferable to form a silver surface layer using water-dispersed polyurethane. The aqueous dispersion can contain a suspension dispersion and an emulsion dispersion. Various additives such as a crosslinking agent, carbon black, thermal expansion microcapsule, flame retardant, chain extender, organic filler, thixotropy imparting agent, antifoaming agent, leveling agent, and surfactant can be contained in the resin. . As the undercoat layer, a polyurethane resin is preferably used, and the same resin as the coating layer can be used.

  The sheet-like material of the present invention can be used as an abrasive cloth suitably used for polishing and / or cleaning. In the method of performing polishing using the polishing cloth of the present invention, a tape obtained by cutting the polishing cloth into a tape having a width of 30 to 50 mm is used as the polishing tape from the viewpoint of processing efficiency and stability.

  A method of polishing an aluminum alloy magnetic recording disk using the polishing tape and slurry containing free abrasive grains is suitable. As a polishing condition, a slurry in which high-hardness abrasive grains such as diamond fine particles are dispersed in an aqueous dispersion medium is preferably used. From the viewpoint of holding and dispersing the abrasive grains, the abrasive grain size suitable for the ultrafine fibers constituting the polishing cloth of the present invention is preferably 0.2 μm or less.

  Next, the sheet-like material of the present invention and the manufacturing method thereof will be described more specifically using examples. Next, the evaluation methods used in the examples and the measurement conditions will be described.

(1) Average single fiber diameter and fiber diameter CV value:
The average single fiber diameter was observed with a scanning electron microscope (SEM) using a cross-section of the sheet-like material cut in the thickness direction as an observation surface, and the single fiber diameters of arbitrary 100 ultrafine fibers were measured. Calculate the standard deviation and mean of the population. The average value was defined as the average single fiber diameter, and the value obtained by dividing the standard deviation by the average value as a percentage (%) was defined as the fiber diameter CV value. When fibers having an average single fiber diameter of more than 5 μm are mixed, the fiber is excluded from the measurement target of the average single fiber diameter as not corresponding to the ultrafine fiber.

(2) Horizontal direction linear density and fiber orientation ratio of fibers arranged in the vertical direction:
With respect to the linear density, 30 sheets of images with an observation magnification of 5000 times are taken with a scanning electron microscope (SEM) using the surface of the sheet-like material as an observation surface. From the photographed image, avoid a portion where a polymer elastic body such as polyurethane is exposed on the surface and no ultrafine fiber is present, or a portion where a large hole is formed by a needle punch or the like, and a reference line of 10 μm is aligned in the horizontal direction. Draw a place. Lines in the horizontal direction of the fibers arranged in the vertical direction by calculating the average value of n number 30 by measuring the number of ultra fine fibers having an acute angle of 60 ° or more intersecting with the reference line in the vertical direction. Density. From the linear density and theoretical linear density (100 μm ÷ single fiber diameter), the fiber orientation ratio (%) is calculated by the following formula.
-Fiber orientation ratio (%) = linear density (book) ÷ theoretical linear density (book).

(3) Napping coverage:
As described above, the napped coverage is increased to 40 times by the scanning electron microscope (SEM) so that the presence of napped fibers can be seen by a scanning electron microscope (SEM). The ratio of the total area of the napped portions per area of 4 mm ² was calculated and used as the napped coverage.

[Example 1]
(raw cotton)
Nylon 6 was used as an island component, and copolymerized polystyrene (co-PSt) obtained by copolymerizing 22 mol% of 2-ethylhexyl acrylate was used as a sea component. Using the sea and island components described above, using a sea island type composite die of 8000 islands / hole, spinning temperature 270 ° C., island / sea mass ratio 15/85, discharge rate 0.9 g / min / hole, spinning speed 1200 m The melt spinning was performed under the conditions of / min. Next, the film was stretched 2.9 times in a liquid bath at a temperature of 85 ° C., crimped using an indentation type crimping machine, cut, an average single fiber diameter of 15.8 μm, and a fiber length of A 51 mm sea-island composite fiber raw cotton was obtained.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
Using the raw cotton, a laminated fiber web was formed through a card process and a cross wrapper process. Next, needle punching was performed using a needle punching machine, and a nonwoven fabric made of ultrafine fiber generating fibers having a basis weight of 820 g / m ² and an apparent density of 0.231 g / cm ³ was produced.

(Sheet)
The nonwoven fabric composed of the above-mentioned ultrafine fiber-generating fibers is subjected to hot water shrinkage at a temperature of 85 ° C., and then, 54% by mass of polyvinyl alcohol having a saponification degree of 88% is given to the fiber mass, and polystyrene as a sea component is obtained using trichlorethylene. After dissolution and removal, drying was performed to obtain a nonwoven fabric composed of ultrafine fiber bundles. A polyurethane DMF solution in which the polymer diol is 75% by mass of a polyether-based polymer diol and 25% by mass of a polyester-based polymer diol, in a solid content with respect to the fiber mass, is obtained on the nonwoven fabric composed of the ultrafine fiber bundles thus obtained. 30% by mass, solidified polyurethane with a 30% DMF aqueous solution at a liquid temperature of 35 ° C., treated with hot water at a temperature of about 85 ° C. to remove DMF and polyvinyl alcohol, and obtained sheet form The product was dried. Thereafter, a sheet-like material was obtained by half-cutting in the thickness direction by a half-cutting machine having an endless band knife. Water is applied to the obtained sheet after half-cutting so as to be 100% by mass with respect to the dry mass, and after squeezing to make it wet, this sheet is supplied to the bafrol, which is opposite to the buffol via the sheet. From the side, napping was formed on the sheet without applying an external force directly opposite to the baffle, and a sheet-like material having napping on one side was produced. As the details of the buffing conditions at this time, wet buffing was performed by using 240 mesh sandpaper for the baffle, a baffle speed of 400 m / min, a sheet conveyance speed of 2.0 m / min, and a sheet contact length of 4 cm between the baffle and the sheet. And water was dried to obtain a sheet.

  The obtained sheet-like material has a sheet-like material thickness of 0.67 mm, an ultrafine fiber average fiber diameter of 0.05 μm, a linear density of 1768 lines / 100 μm width, a fiber orientation rate of 88%, and a napped coverage rate. Was 81%, the deformation ratio of the fiber tip was 15%, and the napped layer thickness was 0.02 mm. It was an elegant surface state with an extremely soft surface touch. The results are shown in Table 1.

[Example 2]
(raw cotton)
Other than using 2000 island / hole sea-island type compound base, island / sea mass ratio 30/70, discharge rate 1.4g / min / hole, average single fiber diameter 24.1μm, fiber length 51mm Produced a raw cotton of sea-island type composite fiber in the same manner as in Example 1.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
In the same manner as in Example 1, a nonwoven fabric made of ultrafine fiber generating fibers having a basis weight of 800 g / m ² and an apparent density of 0.205 g / cm ³ was produced.

(Sheet)
Using the above nonwoven fabric, a sheet-like material was obtained in the same manner as in Example 1. The obtained sheet-like material has a sheet-like material thickness of 0.64 mm, an average fiber diameter of ultrafine fibers of 0.25 μm, a linear density of 340 / μm width, a fiber orientation ratio of 85%, and a napped coverage ratio. Was 76%, the deformation ratio of the fiber tip was 12%, and the napped layer thickness was 0.02 mm. The surface state was graceful with an extremely soft surface touch. The results are shown in Table 1.

[Example 3]
(raw cotton)
A raw cotton was obtained in the same manner as in Example 2 except that polyethylene terephthalate having an intrinsic viscosity of 1.20 was used as the island component and polystyrene was used as the sea component.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
In the same manner as in Example 1, a nonwoven fabric made of ultrafine fiber-generating fibers having a basis weight of 831 g / m ² and an apparent density of 0.225 g / cm ³ was produced.

(Sheet)
A sheet-like material was obtained in the same manner as in Example 2 except that the above-mentioned raw cotton was used to shrink a nonwoven fabric composed of ultrafine fiber-generating fibers at a temperature of 95 ° C. by hot water shrinkage. The obtained sheet-like material has a sheet-like material thickness of 0.66 mm, an average fiber diameter of ultrafine fibers of 0.25 μm, a linear density of 345 fibers / μm width, a fiber orientation ratio of 86%, and a napped coverage ratio. Was 77%, the deformation ratio of the fiber tip was 11%, and the napped layer thickness was 0.02 mm. The surface state was elegant with an extremely soft surface touch. The results are shown in Table 1.

[Example 4]
(raw cotton)
A sea island is obtained in the same manner as in Example 1 except that a 400 island / hole sea-island type composite base is used, an island / sea mass ratio of 30/70, an average single fiber diameter of 29.7 μm, and a fiber length of 51 mm. A raw cotton of type composite fiber was obtained.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
In the same manner as in Example 1, a non-woven fabric made of ultrafine fiber generating fibers having a basis weight of 800 g / m ² and an apparent density of 0.217 g / cm ³ was produced.

(Sheet)
Using the above nonwoven fabric, a sheet-like material was obtained in the same manner as in Example 1. The obtained sheet-like material has a sheet-like material thickness of 0.64 mm, an average fiber diameter of ultrafine fibers of 0.80 μm, a linear density of 110 fibers / μm width, a fiber orientation ratio of 80%, and napped coverage. Was 70%, the deformation ratio of the fiber tip was 10%, and the napped layer thickness was 0.02 mm, and it was an elegant surface state with an extremely soft surface touch. The results are shown in Table 1.

[Example 5]
(raw cotton)
Using a 36 island / hole sea-island type composite base, an island / sea mass ratio of 55/45, a draw ratio of 3.5 times, an average single fiber diameter of 18.4 μm, and a fiber length of 51 mm, Raw material of sea-island type composite fiber was obtained in the same manner as Example 3.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
In the same manner as in Example 3, a nonwoven fabric made of ultrafine fiber generating fibers having a basis weight of 821 g / m ² and an apparent density of 0.223 g / cm ³ was produced.

(Sheet)
Using the above nonwoven fabric, a sheet-like material was obtained in the same manner as in Example 1. The obtained sheet-like material has a sheet-like material thickness of 0.66 mm, an average fiber diameter of ultrafine fibers of 2.1 μm, a linear density of 35 fibers / μm width, a fiber orientation ratio of 80%, and napped coverage. 68%, the deformation ratio of the fiber tip was 8%, and the napped layer thickness was 0.02 mm, which was an elegant surface state with a soft surface touch. The results are shown in Table 1.

[Example 6]
(raw cotton)
In the same manner as in Example 5, a raw cotton of sea-island type composite fiber was obtained.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
In the same manner as in Example 5, a nonwoven fabric made of ultrafine fiber-generating fibers having a basis weight of 821 g / m ² and an apparent density of 0.223 g / cm ³ was produced.

(Sheet)
Using the above-mentioned non-woven fabric, the sheet after half-cut obtained in the same manner as in Example 5 is supplied with water to the baffle without applying water (in the dry state), and the sheet is fed from the opposite side of the buffol through the sheet. An external force directly facing the buffalo was applied (nip roll) to form napped sheets. After dyeing the obtained sheet, the same wet buffing and drying as in Example 5 were performed to obtain a sheet-like material.

  The obtained sheet-like material has a sheet-like material thickness of 0.65 mm, an average fiber diameter of ultrafine fibers of 2.1 μm, a linear density of 32 fibers / μm width, a fiber orientation ratio of 67%, and napped coverage. Was 60%, the deformation ratio of the fiber tip was 35%, the napped layer thickness was 0.15 mm, and it was an elegant surface state with soft surface touch and no irritation. The results are shown in Table 1.

[Example 7]
(raw cotton)
A 16 island / hole sea island type composite die was used, except that the island / sea mass ratio was 80/20, the draw ratio was 2.7 times, the average single fiber diameter was 20.5 μm, and the fiber length was 51 mm. In the same manner as in Example 6, a raw material of sea-island type composite fiber was obtained.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
In the same manner as in Example 6, a nonwoven fabric made of ultrafine fiber generating fibers having a basis weight of 822 g / m ² and an apparent density of 0.224 g / cm ³ was produced.

(Sheet)
Using the above nonwoven fabric, a sheet-like material was obtained in the same manner as in Example 6. The obtained sheet-like material has a sheet-like material thickness of 0.67 mm, an average fiber diameter of ultrafine fibers of 4.4 μm, a linear density of 16 fibers / μm width, a fiber orientation ratio of 78%, and a napped coverage ratio. Was 60%, the deformation ratio of the fiber tip was 30%, and the napped layer thickness was 0.15 mm, and it was an elegant surface state with soft surface touch and no irritation. The results are shown in Table 1.

[Example 8]
(raw cotton)
In the same manner as in Example 2, a raw cotton of sea-island type composite fiber was obtained.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
A nonwoven fabric was produced in the same manner as in Example 2 above.

(Sheet)
Using the above-mentioned nonwoven fabric, the sheet after semi-cutting obtained in the same manner as in Example 2 was applied to the surface on which the water was raised so as to be 40% by mass with respect to the dry mass, and the wet state was carried out. In the same manner as in Example 2, wet buffing and drying were performed to obtain a sheet. The obtained sheet-like material has a sheet-like material thickness of 0.64 mm, an average fiber diameter of ultrafine fibers of 0.25 μm, a linear density of 300 fibers / μm width, a fiber orientation rate of 75%, and a napped coverage rate. 68%, the deformation ratio of the fiber tip was 18%, and the napped layer thickness was 0.02 mm, which was an elegant surface state with an extremely soft surface touch. The results are shown in Table 1.

[Example 9]
(raw cotton)
In the same manner as in Example 2, a raw cotton of sea-island type composite fiber was obtained.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
A nonwoven fabric was produced in the same manner as in Example 2 above.

(Sheet)
Using the nonwoven fabric described above, the sheet after half-cutting obtained in the same manner as in Example 2 was applied to the surface where water was raised so as to be 15% by mass with respect to the dry mass, and the wet state was carried out. In the same manner as in Example 2, wet buffing and drying were performed to obtain a sheet. The obtained sheet-like material has a sheet-like material thickness of 0.64 mm, an average fiber diameter of ultrafine fibers of 0.25 μm, a linear density of 230 fibers / μm width, a fiber orientation ratio of 58%, and a napped coverage ratio. Was 60%, the deformation ratio of the fiber tip was 32%, and the napped layer thickness was 0.02 mm, which was an elegant surface state with a soft surface touch. The results are shown in Table 1.

[Example 10]
(raw cotton)
In the same manner as in Example 5, a raw cotton of sea-island type composite fiber was obtained.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
A nonwoven fabric was produced in the same manner as in Example 5 above.

(Sheet)
Using the above-mentioned non-woven fabric, an external force that directly faces the above-mentioned baffle from the opposite side of the baffle through the sheet-like product is applied to the half-cut sheet-like product obtained in the same manner as in Example 5 (sandwiched with a nip roll) Then, napping was formed on the sheet, and wet buffing and drying were performed in the same manner as in Example 2 to obtain a sheet. The obtained sheet-like material has a sheet-like material thickness of 0.66 mm, an average fiber diameter of ultrafine fibers of 2.1 μm, a linear density of 33 fibers / μm width, a fiber orientation ratio of 69%, and napped coverage. Was 62%, the deformation ratio of the fiber tip was 33%, and the napped layer thickness was 0.10 mm. The surface state was elegant with a soft surface touch. The sheet was suitable as a base material for silver attachment having a high peel strength. The results are shown in Table 1.

[Comparative Example 1]
(raw cotton)
In the same manner as in Example 2, a raw cotton of sea-island type composite fiber was obtained.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
A nonwoven fabric was produced in the same manner as in Example 2 above.

(Sheet)
Using the above non-woven fabric, the sheet after semi-cutting obtained in the same manner as in Example 2 was subjected to the same process as in Example 2 except that water was not applied and buffing was performed in a dry state and not dried. A product was obtained. The obtained sheet-like material has a sheet-like material thickness of 0.64 mm, an average fiber diameter of ultrafine fibers of 0.25 μm, a linear density of 12 fibers / μm width, a fiber orientation rate of 3%, and napped coverage. 43%, most of the fibers were fused and one fiber could not be confirmed, the napped layer thickness was 0.02 mm, and it was a surface state that could not be said to be artificial leather with a rough surface touch. The results are shown in Table 1.

[Comparative Example 2]
(raw cotton)
In the same manner as in Example 2, a raw cotton of sea-island type composite fiber was obtained.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
A nonwoven fabric was produced in the same manner as in Example 2 above.

(Sheet)
Using the above-mentioned nonwoven fabric, water was applied to the post-cut sheet obtained in the same manner as in Example 2 so as to be 100% by mass with respect to the dry mass, and squeezed into a wet state. Was supplied to the baffle, and a sheet-like material was obtained in the same manner as in Example 2 except that buffing was performed by applying an external force (nip roll) directly opposite to the baffle from the opposite side of the baffle through the sheet.

  The obtained sheet-like material has a sheet-like material thickness of 0.59 mm, an average fiber diameter of ultrafine fibers of 0.25 μm, a linear density of 24 fibers / μm width, a fiber orientation ratio of 6%, and a napped coverage ratio. 45%, most of the fibers were fused and one fiber could not be confirmed, the napped layer thickness was 0.04 mm, and it was a surface state that could not be said to be artificial leather with a rough surface touch. The results are shown in Table 1.

[Comparative Example 3]
(raw cotton)
In the same manner as in Example 5, a raw cotton of sea-island type composite fiber was obtained.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
A nonwoven fabric was produced in the same manner as in Example 5 above.

(Sheet)
Using the above-mentioned non-woven fabric, water was applied to the post-cut sheet obtained in the same manner as in Example 5 so as to be 100% by mass with respect to the dry mass, and squeezed into a wet state. Was supplied to the baffle, and a sheet-like material was obtained in the same manner as in Example 5 except that buffing was performed by applying an external force (nip roll) directly opposite to the baffle from the opposite side of the baffle through the sheet. The obtained sheet-like material has a sheet-like material thickness of 0.61 mm, an average fiber diameter of ultrafine fibers of 2.1 μm, a linear density of 18 fibers / μm width, a fiber orientation rate of 38%, and a napped coverage rate. Was 55%, the fiber tip deformation ratio was 28%, and the napped layer thickness was 0.04 mm, which was a surface touch and surface state of ordinary artificial leather. The results are shown in Table 1.

[Comparative Example 4]
(raw cotton)
Using a 15,000 island / hole sea-island type composite base, an island / sea mass ratio of 15/85, a discharge rate of 0.7 g / min / hole, a draw ratio of 4.0 times, an average single fiber diameter of 17.4 μm, A raw cotton of sea-island type composite fiber was obtained in the same manner as in Example 1 except that the fiber length was 51 mm.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
In the same manner as in Example 1, a non-woven fabric made of ultrafine fiber generating fibers having a basis weight of 780 g / m ² and an apparent density of 0.201 g / cm ³ was produced.

(Sheet)
Using the above nonwoven fabric, a sheet-like material was obtained in the same manner as in Example 1. The obtained sheet-like material has a sheet-like material thickness of 0.62 mm, an average fiber diameter of ultrafine fibers of 0.05 μm, a linear density of 876 fibers / μm width, a fiber orientation ratio of 9%, and napped coverage. 34%, and there are many portions in which the ultrafine fibers are not dispersed as napped, and the napped layer thickness is 0.02 mm, which is a surface state that is not elegant with a rough surface touch. The results are shown in Table 1.

[Comparative Example 5]
(raw cotton)
A 16 island / hole sea-island type composite die was used, except that the island / sea mass ratio was 90/10, the draw ratio was 2.5, the average single fiber diameter was 21.5 μm, and the fiber length was 51 mm. In the same manner as in Example 7, raw material of sea-island type composite fiber was obtained.

(Nonwoven fabric made of ultrafine fiber-generating fibers)
In the same manner as in Example 7, a nonwoven fabric made of ultrafine fiber-generating fibers having a basis weight of 822 g / m ² and an apparent density of 0.224 g / cm ³ was produced.

(Sheet)
Using the above nonwoven fabric, a sheet-like material was obtained in the same manner as in Example 7. The obtained sheet-like material has a sheet-like material thickness of 0.64 mm, an average fiber diameter of ultrafine fibers of 9.0 μm, a linear density of 16 fibers / μm width, a fiber orientation ratio of 78%, and a napped coverage ratio. Was 60%, the deformation ratio of the fiber tip was 30%, and the napped layer thickness was 0.15 mm. It was a surface state that was not elegant with a rough surface touch. The results are shown in Table 1.

Claims (12)

  To a sheet comprising a fiber entangled body mainly composed of ultrafine fibers having an average single fiber diameter of 0.01 to 8 μm, 10 to 300% by mass of liquid is applied to the mass of the sheet, and the obtained sheet is used as a baflor. Supplying and buffing one surface of the sheet by wet-buffing the surface of the sheet on the side in contact with the baffle without applying an external force directly facing the baffle from the opposite side of the baffle through the sheet The manufacturing method of the sheet-like material characterized by including.   The method for producing a sheet-like product according to claim 1, wherein wet buffing is performed in a state where 30 to 250 mass% of the liquid is applied to the mass of the sheet.   The method for producing a sheet-like material according to claim 1 or 2, wherein the viscosity of the liquid is 20 mPa · s or less.   The sheet-like product according to any one of claims 1 to 3, wherein the fiber orientation ratio in the horizontal direction of the ultrafine fibers arranged in the vertical direction on at least one side of the napped surface subjected to wet buffing is 40 to 95%. Production method.   5. The sheet-like material according to claim 4, wherein the napped surface ratio of the ultrafine fibers arranged in the vertical direction is 40 to 95%, and the napped surface coverage is 40 to 100%. Method.   The ratio of the ultrafine fibers arranged in the vertical direction to the length of 120 to 300% of the fiber diameter in the napped ultrafine fibers whose fiber orientation ratio in the horizontal direction is 40 to 95%. The method for producing a sheet-like material according to claim 4, wherein the content is 50% or less.   The method for producing a sheet-like product according to any one of claims 1 to 6, wherein the thickness of the raised layer on at least one of the raised surfaces subjected to the wet buffing treatment is 0.20 mm or less.   A sheet-like material comprising a fiber entanglement mainly composed of ultrafine fibers having an average single fiber diameter of 0.01 to 8 μm, wherein one side or both sides of the sheet-like material is a raised surface, and the raised A sheet-like product, wherein a fiber orientation ratio in a horizontal direction of ultrafine fibers arranged in a vertical direction on at least one side of the surface is 40 to 95%.   The sheet-like article according to claim 8, wherein the napped surface coverage of the raised surface where the fiber orientation ratio in the horizontal direction of the ultrafine fibers arranged in the vertical direction is 40 to 95% is 40 to 100%.   The ratio of the ultra-fine fibers arranged in the vertical direction in the raised fibers with the raised surface having a fiber orientation ratio in the horizontal direction of 40 to 95% deformed to 120 to 300% of the fiber diameter. The sheet-like material according to claim 8, wherein the content is 50% or less.   The sheet-like material according to any one of claims 8 to 10, wherein the polymer-like elastic material is contained in the sheet-like material, and the weight thereof is 10 to 60 mass% with respect to the mass of the fiber. .   The sheet-like article according to any one of claims 7 to 10, wherein the thickness of the raised layer on at least one side of the raised surface is 0.20 mm or less.