JP4549844B2 - Suede artificial leather and method for producing the same - Google Patents

Description

  The present invention is an environmentally-friendly manufacturing method that has suede feeling, surface touch, denseness and fullness similar to those of natural leather, water resistance such as color development and fastness to moisture, and mechanical properties such as tear strength. Industrially stable suede-like artificial leather.

Conventionally, artificial leather has been developed mainly composed of ultrafine fibers and polymer elastic bodies. Suede-like artificial leather made of such ultrafine fibers has a suede feel, surface touch, and flexibility. It has been evaluated as a material close to natural leather.
Conventionally, from the viewpoint of environment, a method using a water-dispersed elastic body as a polymer elastic body (for example, see Patent Documents 1, 2, and 3) has been proposed, but a solvent system conventionally used in artificial leather. Compared with polyurethane, water absorption is generally high and water resistance is inferior. Therefore, swelling of the polymer elastic body occurs in the water treatment process such as the dyeing process, and the polymer elastic body falls off, or the ultrafine fibers inside the ultrafine fiber bundle The suede-like artificial leather obtained has a problem that it is inferior in suede feeling, surface touch, texture, and tearing strength, and the water-dispersed resin drops off due to rubbing when used, especially when wet. There are problems that tend to occur. In addition, pigments are conventionally added to the polymer elastic body for the purpose of enhancing the sense of quality and light resistance, but these problems become more prominent when pigments are added to water-dispersed resins. It has become more difficult to obtain a high-quality, suede-like artificial leather with excellent light resistance.

  As a method for ultrafinening, conventionally, a method of ultrafinening by performing a solvent extraction process using a solvent extractable component as one component of a fiber has been mainly performed. However, in the extraction method, regardless of whether it is a solvent extraction method or a water extraction method, a small amount of the extractable component tends to remain, and due to the remaining, the suede feeling of the suede-like artificial leather, surface touch, texture, Performance tends to be affected.

From the standpoint of environmental friendliness, studies have been actively conducted in recent years to switch to a method of ultra-thinning by performing a water extraction process using a water-soluble polymer component as one component of a fiber. When ultra-fine by water treatment, a small amount of water-soluble polymer component remains after extraction, glues the ultra-fine fibers inside the ultra-fine fiber bundle like glue, the suede feeling of the resulting suede-like artificial leather, surface touch, There is a tendency that texture and tear strength are inferior. Furthermore, due to the presence of a small amount of water-soluble polymer component having high hydrophilicity, the resulting suede-like artificial leather has a high water absorption and tends to cause color transfer under moisture.
In particular, when a water extraction method and a water-dispersed resin are combined, the water swellability, high water absorption, and low water resistance of the polymer elastic body are combined with the high water absorption associated with the remaining water-soluble polymer component. There is a tendency that the suede feeling, surface touch, texture, tear strength, and color transfer under moisture of the suede-like artificial leather to be produced are inferior.
In addition, these are affected by subtle fluctuations in manufacturing conditions such as extraction, and it is difficult to stably obtain a product of constant quality, and there is a problem in production stability.

  In other words, in environmentally-friendly suede-like artificial leather, a suede-like artificial leather material with good suede feeling, surface touch, texture, color development, various toughnesses and good mechanical properties has been strongly demanded, but it has been done conventionally. Overcoming with the approach has already reached its limit, and there is still no satisfaction.

JP-A-55-128078 JP-A-6-316877 JP-A-9-132976

  The present invention is an environmentally-friendly manufacturing method that has suede feeling, surface touch, denseness, and fullness similar to natural leather, water resistance such as color development and fastness to moisture, and mechanical properties such as tear strength. Industrially stable suede-like artificial leather.

That is, the present invention is composed of a fiber entangled body composed of an ultrafine fiber bundle and a polymer elastic body, and the following (1) ultrafine fiber generation type fiber is composed of a water soluble polymer component and a poorly water soluble polymer component. It is made very fine and is composed of fibers having a single fiber fineness of 0.0003 to 0.4 dtex,
(2) The resin constituting the polymer elastic body is a water-dispersed resin,
(3) A suede-like artificial leather characterized in that a perfluoroalkyl acrylate-based polymer is attached to the inside of an ultrafine fiber bundle, the surface thereof, and a polymer elastic body.
Moreover, it is preferable that the perfluoroalkyl acrylate-type polymer adheres 0.05-5 mass%, and it is preferable that the water absorption of a suede-like artificial leather is 5-80%.
Furthermore, it is preferable that the resin constituting the polymer elastic body is a water-dispersed resin composed of at least one of polyurethane, acrylic, and polyurethane-acrylic composite resin, and has 0.1 to 10% by mass of pigment. Residual rate of the polymer elastic body containing the pigment becomes 95% or more after ultrafine fiber-generating fibers composed of a water-soluble polymer component and a poorly water-soluble polymer component are further finely dyed. Preferably, the polymer elastic body has a weight swelling rate of 130% or less in hot water at 130 ° C. and a drop-off rate of 3% or less, and the polymer elastic body is treated with 50 ° C. methyl ethyl ketone. It is preferable that the weight swell ratio is 150% or less and the drop-off ratio is 5% or less.

  The present invention is a method for producing an environmentally-friendly suede-like artificial leather, in which the polymer elastic body is a water-dispersed resin and the ultrafine fiber generating fiber is further refined by a water extraction method. The present invention provides an industrially stable suede-like artificial leather that has surface touch, fineness, and fullness, and excellent mechanical properties such as water resistance such as color developability and fastness to moisture and friction, and tear strength.

Hereinafter, the present invention will be described in detail.
That is, the inventors of the present invention have a problem in a method for producing an environmentally-friendly suede-like artificial leather by ultrafinening of ultrafine fiber-generating fibers by a water extraction method, wherein the polymer elastic body is a water-dispersed resin. (1) Suede feel, surface touch, texture, tear strength of the resulting suede-like artificial leather due to the fact that the water-dispersed resin is easily swelled with hot water and a minute amount of water-soluble polymer component remains, resulting in the ultrafine fibers sticking together Inferior problem. (2) Since the water-dispersed resin and a small amount of the remaining water-soluble polymer component have high water absorption, color transfer is liable to occur due to rubbing under wet conditions during use. Furthermore, the present inventors have conducted intensive studies on the problems (1) and (2) that are remarkably worsened when a pigment is added to a water-dispersed resin. As a result, 0.05 to 4% by weight of a perfluoroalkyl acrylate polymer is contained in the inside of the ultrafine fiber bundle and on the surface and the polymer elastic body, and a water-dispersible water-dispersed resin is used for the polymer elastic body. Furthermore, by reducing the remaining amount of the water-soluble polymer component, these problems can be solved, and it has a suede feeling, surface touch, denseness, and fullness similar to those of natural leather. The present inventors have found that a suede-like artificial leather excellent in mechanical properties such as water resistance and tear strength can be provided industrially and stably.

  Moreover, the ultrafine fiber generating fiber of the present invention needs to be composed of a water-soluble polymer component and a poorly water-soluble polymer component. The water-soluble polymer component indicates a component from which the component is extracted and removed by an aqueous solution, and the poorly water-soluble polymer component indicates a component that is difficult to extract and remove by an aqueous solution. The ultrafine fiber generating fiber composed of a water-soluble polymer component and a poorly water-soluble polymer component can be used as long as at least one component can be extracted and removed by extraction with an aqueous solution. Any of multicomponent composite fibers may be used. Here, when the water-soluble polymer component is not water-soluble but soluble in an organic solvent, the organic fiber is used to make the ultrafine fiber-generating fiber ultrafine, not only polluting the environment, Part of the pigment contained in the polymer elastic body is dissolved and removed, and the resulting suede-like artificial leather has poor color developability or inferior industrial productivity. As the water-soluble polymer component used in the present invention, a known polymer can be used as long as it is a spinnable polymer that can be extracted with an aqueous solution (hereinafter also referred to as an aqueous solvent). It is preferable to use soluble polyvinyl alcohol copolymers (hereinafter sometimes abbreviated as PVA). PVA can be easily dissolved and removed with hot water, and due to the shrinkage behavior when it is extracted and removed with an aqueous solvent, structural crimps appear in the ultrafine fiber-generating fiber of the sparingly water-soluble polymer component (ultrafine fiber component). The entangled body becomes bulky and dense, and an artificial leather substrate with an excellent texture like natural leather can be obtained, and the decomposition reaction of ultrafine fiber components and polymer elastic body components during extraction and removal In view of the fact that there is no limitation on the thermoplastic resin and the polymer elastic body component used for the poorly water-soluble polymer component (ultrafine fiber component), and in consideration of the environment, it is preferably used.

The PVA may be a homopolymer or a modified polyvinyl alcohol introduced with a copolymer unit. However, from the viewpoints of melt spinnability, water solubility, fiber properties, and shrinkage characteristics during extraction processing, the copolymer unit may be Preferably, the introduced PVA is an α-olefin having 4 or less carbon atoms such as ethylene, propylene, 1-butene, isobutene, methyl vinyl ether, ethylene vinyl ether, n-propyl vinyl ether, i-propyl vinyl ether, n-butyl vinyl ether. More preferred are vinyl ethers such as Moreover, it is preferable that 1-20 mol% of units derived from α-olefins having 4 or less carbon atoms and / or vinyl ethers are present in PVA. Furthermore, when the α-olefin is ethylene, fiber properties are high, and solubility in hot water is improved, so that PVA modified with 4 to 15 mol% of ethylene units is particularly used. Is more preferable.
The saponification degree is preferably 90 to 99.99 mol%, more preferably 92 to 99.98 mol%, further preferably 94 to 99.96 mol%, and particularly preferably 95 to 99.95 mol%. When the saponification degree is less than 90 mol%, the thermal stability of PVA is poor and satisfactory composite melt spinning cannot be performed by thermal decomposition or gelation. On the other hand, PVA having a saponification degree larger than 99.99 mol% is difficult to produce stably. Furthermore, the primary structure and higher order structure of PVA are adjusted to control the crystallinity and water solubility, thereby adjusting to appropriate hot water solubility.

  In addition, when PVA of a type that elutes into water at room temperature is used as the water-soluble polymer component, the water-soluble polymer component may elute during the impregnation of the water-dispersed resin and contaminate the polymer elastic water dispersion. There is also a tendency that the polymer elastic body impregnated when the fine fiber portion is exposed due to partial elution of the water-soluble polymer component enters the ultrafine fiber bundle and hardens the texture of the resulting suede-like artificial leather. Therefore, it is preferable to use as a water-soluble polymer component a PVA of a type that is easily eluted with hot water at 60 to 100 ° C. Furthermore, by eluting the water-soluble polymer component with hot water at 60 to 100 ° C., the PVA remaining in the suede-like artificial leather can be reduced to 1% or less, and the shrinkage behavior of the fiber entangled body occurs, resulting in structural crimping. Is preferable in that an artificial leather base having an excellent texture similar to that of natural leather can be obtained.

The poorly water-soluble polymer component of the present invention is not particularly limited as long as it is a known ultrafine fiber, for example, a polyamide-based, polyester-based, or polyolefin-based component. And, since spinning of PVA at high temperature leads to deterioration of spinnability, it is preferable to appropriately select the melting point of the poorly water-soluble polymer component constituting the ultrafine fiber, and as the hardly water-soluble polymer component constituting the ultrafine fiber, From the viewpoint of spinning stability of the ultrafine fiber-generating fiber, it is preferable to select a thermoplastic component having a melting point between the melting point of the water-soluble polymer component extracted and removed in the process of forming the fiber and + 60 ° C. For example, polyethylene terephthalate, polybutylene terephthalate, polyethylene terephthalate copolymerized with isophthalic acid, polyester resin typified by polybutylene terephthalate copolymerized with isophthalic acid, or nylon 6, nylon 11, nylon 12, etc. Polyamide resins are preferred. The melting point of the water-soluble polymer component is preferably 160 to 230 ° C. from the viewpoint of spinnability.
The mass ratio of the water-soluble polymer component and the poorly water-soluble polymer component constituting the ultrafine fiber generating fiber is in the range of 10/90 to 60/40, and the cross-sectional formability of the ultrafine fiber generating fiber is good. Yes, because the water-soluble polymer component completely covers the ultrafine fibers, uniform penetration inside the fiber entangled body is obtained, and it is advantageous for uniform impregnation with water-dispersed resin, or an artificial leather base In this case, since the cross-sectional formability is good, the entangled state of the ultrafine fibers generated is uniform, which is preferable in that the texture of the obtained artificial leather is not impaired.

The fineness of the ultrafine fiber-generating fiber of the present invention can be arbitrarily selected depending on the use of the artificial leather and is not particularly limited. However, the single short fiber constituting the fiber entangled body composed of the ultrafine fiber bundle after the ultrafine fiber formation is 0. It has a fineness of .0003 to 0.4 dtex, preferably has a fineness of 0.003 to 0.2 dtex, and more preferably has a fineness of 0.007 to 0.1 dtex in producing an artificial leather substrate. .
In addition, the fibers constituting the yarn of the woven or knitted fabric when used in combination with the woven or knitted fabric are 0.0003 to 1.6 dtex, preferably 0.0003 to 1.0 dtex after ultrafinening, and further the fineness of the ultrafine fibers constituting the short fibers. An equivalent level of 0.0003 to 0.4 dtex is particularly preferable from the viewpoint of the texture and the appearance of surface napping when it is made into a suede-like artificial leather.
In the case of short fibers, the average fiber length is preferably 18 to 110 mm. If the fiber length is not more than 18 mm, effective entanglement cannot be achieved, and if it exceeds 110 mm, the process passability such as card processing tends to decrease. However, after the subsequent processing such as slicing and buffing, the final product may contain some fibers that have been cut and become less than 18 mm. This is an effective entanglement. Since it is a fiber generated after the achievement, there is no particular inconvenience. In addition, the average fiber length is preferably 20 to 80 mm from the viewpoint of the process passability.

In the fiber entangled body of the present invention, it is preferable that 0.01 to 5% by mass of a pigment is added so as to develop a color with a small amount of dye. In this case, if the final product needs a light-colored system, that is, a color developability as a light color or a light color, a small amount of pigment is required, and the addition of the pigment inside the ultrafine fiber is at a low concentration. That is, when the color of the appearance required as the final product is light, the amount of pigment added to the inside of the ultrafine fibers is preferably 0 to 1% by mass, and in the case of medium color, 1 to 2% by mass is preferable, and the dark color In this case, it is preferably 2 to 5% by mass, and if it exceeds 5% by mass, the spinning processability and the fiber strength are lowered, and the tear strength of the artificial leather obtained as a result tends to be lowered. In addition, since the appearance may be impaired when the color of the woven or knitted yarn exposed on the surface is significantly different from the color of the nonwoven fabric made of short fibers, the fineness of the yarn constituting the nonwoven fabric made of short fibers and the woven or knitted fabric, and the It is preferable that the amount of pigment added to the fiber is as close as possible, but the island fineness generated from the woven / knitted yarn / the island fineness generated from the short fiber = 0.5 to 4.0, and the pigment concentration in the woven / knitted yarn / Pigment concentration in the nonwoven fabric made of short fibers is preferably in the range of 0.1 to 10.
In the present invention, the ultrafine fiber generating fiber is composed of a water-soluble polymer component and a poorly water-soluble polymer component, and an aqueous solution is used instead of an organic solvent when extracting the water-soluble polymer component. Without using a special pigment, the pigment does not fall off during the extraction of the pigment, and it is possible to prevent lightening and color fluctuation due to the reduction of the pigment in the extraction, and contamination of the extraction bath.

The pigment to be used is not particularly limited, and for example, inorganic pigments such as titanium oxide and carbon black, and organic pigments such as phthalocyanine-based and anthraquinone-based pigments that are usually used for polymer deposition can be used. In addition, when the pigment contained in the ultrafine fiber is carbon black, the carbon black is mixed and integrated in the polymer constituting the ultrafine fiber, and is mainly embedded in the polymer constituting the ultrafine fiber. The average primary particle size of carbon black is preferably 10 to 60 nm. When the average primary particle size of the carbon black is less than 10 nm, it is difficult to obtain uniform fibers due to the tendency of the carbon black to aggregate during spinning, and the quality stability of color spots, physical spots, etc. This problem tends to occur, and the spinnability tends to decrease. On the other hand, when the average primary particle size of carbon black exceeds 60 nm, the light fastness and color developability of the resulting suede-like artificial leather tend to decrease, and filter clogging easily occurs during the spinning process. Tend to decrease. Carbon black generally exists as an aggregate of a plurality of primary particles (hereinafter referred to as an aggregate), but carbon black is mixed and integrated in the polymer constituting the ultrafine fiber, and mainly constitutes the ultrafine fiber. The average particle size of the aggregate is more preferably 20 to 200 nm because it is easily embedded in the polymer to be embedded and has good color developability, light fastness and spinnability. In addition, in other inorganic pigments and organic pigments, the average particle size is more preferably 20 to 200 nm for the same reason.
In addition, as a method for adding the pigment, in order to improve the dispersibility of the pigment in the polymer constituting the ultrafine fiber, the polymer and the pigment constituting the ultrafine fiber are kneaded using a compound facility such as an extruder and then pelletized. It is preferable to adopt the master batch method. In addition, a stabilizer such as a copper compound, a colorant, an ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, a flame retardant, and a plasticizer are included in the ultrafine fiber component as long as the purpose and effect of the present invention are not impaired. Further, a lubricant and a crystallization rate retarder may be added during the polymerization reaction or in the subsequent steps. The type of fine particles is not particularly limited, and for example, inert fine particles such as silica, alumina, titanium oxide, calcium carbonate, and barium sulfate can be added. These may be used alone or in combination of two or more. In some cases, spinnability and stretchability may be improved.

  The above-mentioned ultrafine fiber-generating fiber is usually drawn after spinning, but may be drawn once after being discharged from the spinning nozzle and then drawn, or may be drawn before winding, and any method may be used. The stretching method is usually hot stretching, but may be performed using any of steam heating, infrared heating, hot air, hot plate, hot roller, water bath and the like. However, when one component of the ultrafine fiber generating fiber is a water-soluble polymer component, it is preferably stretched in a heating atmosphere with little influence of moisture.

In the present invention, either short fibers or long fibers can be used. However, in the case of short fibers, a woven or knitted fabric may be used in combination in order to improve the mechanical properties of the resulting suede-like artificial leather. When a knitted fabric is used, the yarn constituting the knitted fabric has 10 fibers as described above. It is preferable that ~ 200 pieces are assembled. Moreover, the twist number of this woven or knitted fabric is 10-650 T / m, and 15-500 T / m is preferable. If it is less than 10 T / m, the single yarn of the knitted or knitted fabric is completely scattered when entangled with the nonwoven fabric composed of short fibers as will be described later, and the single yarn is severely cut during the entanglement treatment, and strong with the short fibers. The entanglement is not performed, and the effect of reducing the polymer elastic body is reduced. On the other hand, when the twist number exceeds 650 T / m, it is difficult to obtain an integral structure tightly entangled with a nonwoven fabric made of short fibers, which is inappropriate for obtaining a natural leather-like texture. The woven or knitted fabric basis weight can be set as appropriate depending on the purpose, is preferably ^{20~200g / m 2, 30~150g / m} 2 is more preferable. When the basis weight is less than 20 g / m ² , the form of the woven or knitted fabric becomes very loose, and the shape stability of the fabric tends to decrease, such as misalignment, and when the basis weight exceeds 200 g / m ² , the woven or knitted fabric becomes dense. Therefore, the nonwoven web tends to be insufficiently penetrated, and the non-woven web does not become highly entangled, making it difficult to produce a structure that is separated and integrated. As the types of woven and knitted fabrics, weft knitting represented by warp knitting and tricot knitting, lace knitting and various knittings based on these knitting methods, or plain weaving, twill weaving, satin weaving and weaving these The various woven fabrics are not particularly limited. Which one to select, such as tissue or density, may be determined appropriately according to the purpose. Moreover, you may perform a false twist process as needed.

And it can manufacture using a well-known method as a fiber entanglement body of this invention. In the case of a long fiber entangled body, it can be produced by a method of producing the ultrafine fiber-generating fiber obtained above as it is by a known spunbond method or a combination of various entanglement methods. In the case of a fiber entangled body composed of short fibers, for example, first, the ultrafine fiber generating fiber obtained above is crimped and then stapled, a web is formed with a card, a cross wrapper, a random web, etc., needle punch or high pressure A fiber entangled body made of a nonwoven fabric is produced by entanglement of fibers by performing a known entanglement process such as a water flow process.
Alternatively, ultrafine fiber-generating fibers are crimped and then stapled, a web is formed with a card, a cross wrapper, a random web, etc., and a woven or knitted fabric using the above fibers is laminated on the surface layer, lower layer, or intermediate layer of the web Then, the nonwoven fabric and the fibers constituting the woven or knitted fabric are entangled by performing a known entanglement treatment such as needle punching or high-pressure water flow treatment. Needle punching is preferably used because it is difficult to dissolve the water-soluble polymer component. As the needle punch condition, it is preferable to use a needle punch condition in which the woven or knitted fabric constituting fiber penetrates the nonwoven fabric surface. When a nonwoven fabric composed of reinforcing knitted fabric constituent fibers and short fibers is used, it is preferable to perform needle punching so that the woven or knitted fabric constituent fibers are exposed to some extent in order to advance the entanglement. Is preferable from the viewpoint of obtaining an appearance for natural leather. That is, it is preferable to expose the reinforcing woven or knitted fabric fibers on the surface side of the nonwoven fabric and to expose the nonwoven fabric constituting fibers on the surface side of the reinforcing woven or knitted fabric. The ratio of the nonwoven fabric made of short fibers to the woven or knitted fabric is preferably 0/100 to 10/90, more preferably 20/80 to 60/40. When the ratio of the nonwoven fabric made of short fibers to the woven or knitted fabric is less than 10/90, the woven or knitted fabric tends to be exposed on the surface, which becomes a suede of a fabric-like surface feeling and lacks a high-class feeling.
As specific needle punch conditions, a condition that the barb of the needle needle penetrates to the surface of the nonwoven fabric and a number of needle punches of 400 to 5000 punch / cm ² is preferable, and more preferably 1000 to 2000 punch / cm ^2. Is the condition.

  The obtained fiber entangled body is preferably subjected to dry heat shrinkage, hot water shrinkage, hot pressing as required, and dry heat shrinkage treatment and hot press are preferably performed. The shrinkage treatment reduces the area of the fabric to 40 to 40 before shrinkage. 90%. This shrinkage treatment provides a dense structure, and with a low shrinkage in which the degree of shrinkage exceeds 90% of the area before shrinkage, a dense feeling cannot be obtained and the texture and suede feeling are inferior, and the short fibers are easily removed. The required amount of the elastic polymer for fixing it tends to increase. Conversely, when the shrinkage is large such that it is less than 40% of the area before shrinkage, the texture is hardened, which is not preferable. The shrinkage treatment is preferably performed by leaving the entangled and entangled body in an atmosphere of 160 to 200 ° C. for 0.5 to 3 minutes.

If necessary, the nonwoven fabric may be temporarily fixed by applying a water-soluble paste such as a polyvinyl alcohol-based resin that can be dissolved and removed, or for smoothing the surface or adjusting the specific gravity. Heat treatment such as pressing may be performed.
The thickness of the fiber-entangled nonwoven fabric can be arbitrarily selected depending on the use of the artificial leather to be obtained, and is not particularly limited, but the thickness is preferably about 0.2 to 10 mm, 0.4 to 5 mm More preferably, it is about. The density is preferably 0.20 to 0.80 g / cm ^{3, and} more preferably 0.30 to 0.70 g / cm ³ . If it is less than 0.20 g / cm ³ , the fiber's feeling of nap is insufficient, and the mechanical properties tend to be lowered. If it exceeds 0.80 g / cm ³ , the texture of the artificial leather obtained tends to be hard.

The water-dispersed resin imparted to the fiber entangled body in the present invention is preferably a polyurethane water-dispersed resin and / or a water-dispersed resin obtained by combining an acrylic resin and a polyurethane resin, and the polymer elastic body has an average particle size of 0. It is preferable to have 0.1 to 10% by weight of carbon black and / or organic pigment of 0.05 to 0.6 μm, high weight swelling rate at 130 ° C. hot water of 20% or less, dropout rate of 2% or less A molecular elastic body is more preferable.
As the diisocyanate used in the polyurethane constituting the polymer elastic body of the present invention, a known diisocyanate component may be selected according to the use and required performance. For example, an aliphatic or alicyclic type having no aromatic ring. Non-yellowing type diisocyanate composed of organic diisocyanate (hereinafter also referred to as non-yellowing type diisocyanate), such as hexamethylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, and aromatics Examples of the diisocyanate, that is, a diisocyanate having an aromatic ring used as a diisocyanate component such as polyurethane include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4, Known aromatic diisocyanates such as 4′-diphenylmethane diisocyanate and xylylene diisocyanate can be exemplified. In the case of using aromatic diisocyanate, in the obtained suede-like artificial leather, photodiscoloration and thermal discoloration due to yellowing of the polymer elastic body due to light and heat, and photodegradation and heat of the polymer elastic body. Light fading and heat fading of pigments and dyes due to degradation are likely to occur, resulting in poor light fastness and heat fastness, and heat-degraded polymer elastic bodies accumulated in the dyeing machine. Contamination can easily cause problems in the dyeing process and must be used with caution. Alternatively, it is necessary to use a specific pigment with excellent light resistance or a specific pigment with low heat storage such as infrared rays, which not only causes manufacturing cost problems, but also requires coloring with limited pigments. Therefore, it may be difficult to obtain a variety of colors. In addition, unless it is the use which does not require high light resistance and high heat resistance, aromatic organic isocyanate can be used as organic diisocyanate in the range which does not inhibit the effect of this invention.

  As the polymer polyol used in the polyurethane of the present invention, a known polymer polyol may be selected according to the use and required performance. For example, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, poly (methyltetramethylene glycol) Polyether polyol such as polybutylene adipate diol, polybutylene sebacate diol, polyhexamethylene adipate diol, poly (3-methyl-1,5-pentylene adipate) diol, poly (3-methyl-1,5-pentylene) Polyester polyols such as sebacate) diol and polycaprolactone diol; polyhexamethylene carbonate diol, poly (3-methyl-1,5-pentylene carbonate) diol, polypenta Chi Ren carbonate diol, a polycarbonate-based polyol such as polytetramethylene carbonate diol; and polyester carbonate polyols can be used, it is possible to use one or more of these. In particular, the obtained suede-like artificial leather has good light fastness, heat fastness, NOx yellowing resistance, sweat resistance, hydrolysis resistance, etc., and a highly crystalline polycarbonate system. When 90% or more of the polyol is used, from the viewpoint that the washing out of the dye in the dyeing process tends to be insufficient, and the suede feeling and texture of the resulting suede-like artificial leather tend to be inferior, As a particularly preferable example, it is particularly preferable to use a polymer polyol in which two or more of polyether, polyester, polycarbonate and the like are used in combination, or to use a polymer polyol mainly composed of polycarbonate having a reduced crystallinity. It is done.

As the chain extender component used in the polyurethane of the present invention, a chain extender used in the production of a known urethane resin may be selected according to the use and required performance. For example, hydrazine, ethylenediamine, propylenediamine , Hexamethylenediamine, nonamethylenediamine, xylylenediamine, isophoronediamine, piperazine and derivatives thereof, diamines such as adipic acid dihydrazide, isophthalic acid dihydrazide; triamines such as diethylenetriamine; tetramines such as triethylenetetramine; ethylene glycol, Diols such as propylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,4-bis (β-hydroxyethoxy) benzene, 1,4-cyclohexanediol; trimethylolpro Triols such as down; pentaols such as pentaerythritol; aminoethyl alcohol, and amino alcohols such as amino propyl alcohol and the like, may be used alone or two or more of them. Among them, since solidification of the polymer elastic body is completed by a short heat treatment after impregnation, and there is little dropout in the dyeing process, there are few hydrazine, piperazine, hexamethylenediamine, isophoronediamine and its derivatives, and triamines such as ethylenetriamine. 2 to 4 types are preferably used in combination. In addition, during the chain extension reaction, together with the chain extender, monoamines such as ethylamine, propylamine, and butylamine; carboxyl group-containing monoamine compounds such as 4-aminobutanoic acid and 6-aminohexanoic acid; methanol, ethanol, propanol, butanol, etc. Monools may be used in combination.
In addition, an ionic group such as a carboxyl group may be introduced into the resin skeleton of the polyurethane-based polymer in order to impart a particle size or various performances of the water-dispersed resin. The method is not particularly limited, but 2,2-bis (hydroxymethyl) propionic acid, 2,2-bis (hydroxymethyl) butanoic acid, 2,2-bis (hydroxymethyl) valeric acid and the like as raw materials for urethane resin The carboxyl group-containing diol is a preferred example. In particular, when the carboxyl group content of the carboxyl group-containing bifunctional compound is 5 to 30 mmol / 100 g in the polyurethane-based polymer, there is a tendency that there is little dropout in the dyeing step.

A preferred example of the polymer elastic body of the present invention is to use an acrylic-polyurethane composite type polymer elastic body in which an acrylic component is combined with the above-described polyurethane component. In addition, the polyurethane component constitutes a sea with an island structure, the acrylic component constitutes an island component with a sea island structure, and the polyurethane component forms a continuous phase and the acrylic component forms a discontinuous phase. It is preferable in terms of good performance such as leather suede, surface touch and mechanical properties, and the presence of pigments mixed and integrated in polyurethane suppresses pigment dropout and improves fastness such as friction fastness. It is preferable in terms of securing. The phase structure of the polyurethane component and the acrylic component can be confirmed by using a transmission electron microscope or the like.
The acrylic-urethane composite type resin is obtained by a known method such as a method of emulsion polymerization of an ethylenically unsaturated monomer having a (meth) acrylic acid derivative as a main component in the presence of an aqueous urethane resin dispersion. Moreover, it can carry out similarly to the emulsion polymerization of a conventionally well-known ethylenically unsaturated monomer. As ethylenically unsaturated monomers, (meth) acrylic acid alkyl esters such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate are the main components. It is preferable to use it. Furthermore, polyfunctional ethylene such as 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, divinylbenzene, allyl (meth) acrylate, etc. It is preferable to copolymerize a small amount of the polymerizable unsaturated monomer to make the resin a crosslinked structure.

  The polymer elastic body may contain a crosslinking agent for the main resin. The crosslinking agent is a compound containing in the molecule two or more functional groups capable of reacting with the functional group of the main resin, and the combination of the functional group of the main resin and the functional group of the cross-linking agent is a carboxyl group and an oxazoline group. Carboxyl group and carbodiimide group, carboxyl group and epoxy group, carboxyl group and cyclocarbonate group, carboxyl group and aziridine group, carbonyl group and hydrazide group, and the like. Among these, a combination of a main resin having a carboxyl group and a cross-linking agent having an oxazoline group or a carbodiimide group is preferable because of excellent liquid stability and easy production.

  The nitrogen content of polyurethane in the acrylic-polyurethane composite type polymer elastic body of the present invention is preferably in the range of 2.0 to 5.0 mass%. When the nitrogen content is less than 2.0% by mass, it becomes difficult for the polyurethane component to have a sea-island-structured sea (continuous phase) and the acrylic component to be a sea-island-structured island (non-continuous phase). The polymer elastic body tends to swell and fall off in the dyeing process and is inferior in dyeing process properties, and the texture and suede feeling of the resulting suede-like artificial leather, as well as inferior mechanical properties such as tensile strength Or water absorption tends to increase. Conversely, when the nitrogen content of the polyurethane exceeds 5% by mass, the resulting suede-like artificial leather tends to have a firm texture.

  The mass ratio of the polyurethane component to the acrylic component of the polyurethane-acrylic composite is preferably 10:90 or more. When the mass ratio of the polyurethane component and the acrylic component is less than 10:90, it becomes difficult for the polyurethane component to take a sea-island structure sea (continuous phase) and the acrylic component is a sea-island structure island (non-continuous phase), The polymer elastic body is likely to fall off in the extraction process and the dyeing process, and the resulting suede-like artificial leather has inferior mechanical properties such as texture and suede feeling and tensile strength.

  The polymer elastic body of the present invention is a penetrant, a thickener, an antioxidant, an ultraviolet absorber, a film-forming aid, a heat-sensitive gelling agent, a softener, a lubricant, an antifouling, as long as the characteristics of the present invention are not impaired. An agent, a fluorescent agent, an antifungal agent, a flame retardant, a water-soluble polymer compound such as polyvinyl alcohol and carboxymethyl cellulose, and a dye may be appropriately contained.

The pigment and the polymer elastic body contained in the polymer elastic body of the present invention include a step of obtaining a suede-like artificial leather, that is, a step of water-extracting or dyeing a water-soluble polymer component of an ultrafine fiber-generating fiber. In the process, it is preferable not to fall off. Specifically, in the present invention, the residual ratio in the production process of the polymer elastic body containing the pigment is preferably 95% or more, and more preferably 97% or more. The residual rate is the same conditions as in the actual production, for example, 90 ° C. hot water treatment, by mixing the pigment contained in the polymer elastic body and the polymer elastic body at a predetermined ratio for actually producing the film. After the extraction, the mass retention after the high temperature dyeing treatment at 130 ° C., the alkali washing treatment, the acid neutralization treatment and the water washing treatment is defined as the residual rate. When the residual ratio is less than 95%, the friction fastness, color development, and sharpness of the suede-like artificial leather obtained by dropping off pigments and polymer elastic bodies are reduced, and color blurring increases and color matching occurs. Not only becomes complicated, but also stains occur in a dyeing machine or the like, and there is a tendency for dyeing process properties to deteriorate.
In order to make the residual ratio of the sum of the pigment contained in the polymer elastic body and the polymer elastic body 95% or more, it is possible to select the above-mentioned suitable requirements for polyurethane and acrylic. The polymer elastic body has a hot water swelling ratio of 20% or less immediately after being immersed in hot water at 130 ° C., and a dropout ratio after being immersed in hot water at 130 ° C. is 2.0%. The following is preferable. Furthermore, it is preferable that the drop-off rate after performing an alkali washing treatment, an acid neutralization treatment and a water washing treatment after the high temperature dyeing treatment at 130 ° C. as in the normal dyeing step is 2.0% or less. When the hot water swelling rate of the polymer elastic body exceeds 20% or the drop-off rate exceeds 2%, the polymer elasticity is increased when ultrafine treatment or softening treatment with aqueous solution or dyeing with a dye is performed. The body swells and deforms, causing pigments and polymer elastic bodies to fall off, and the polymer elastic bodies cannot grip the fibers, and the suede feeling and surface touch tend to deteriorate. It tends to be inferior in friction fastness. In particular, water-dispersed resins tend to have a higher hot water swelling rate at 130 ° C. than solvent-based polymer elastic bodies, and it is preferable in the present invention to reduce the hot water swelling rate and drop-off rate at 130 ° C. .

  Since the hydrothermal swelling property and drop-off rate of the polymer elastic body are considered to correlate with the crosslink density of the polymer elastic body, it is a solvent that easily swells the polymer elastic body, such as methyl ethyl ketone, toluene, N, It can also be evaluated by measuring the mass swelling rate and mass retention rate of N, -dimethylformamide or acetone. Specifically, the mass swelling rate immediately after being immersed in methyl ethyl ketone at 50 ° C. for 5 hours is 150% or less and the dropout rate is 5% or less, more preferably the mass swelling rate is 120% or less and the dropout rate is 3% or less. Preferably, the mass swelling rate immediately after being immersed in toluene at 90 ° C. for 1 hour is 200% or less, the dropout rate is 10% or less, more preferably the mass swelling rate is 150% or less, and the dropout rate is 6% or less. Preferably there is. Further, after dipping in 90 ° C. hot water, after performing a high temperature dyeing treatment at 130 ° C., an alkali washing treatment, an acid neutralization treatment, and a water washing treatment in the same manner as a normal dyeing process, it was dipped in methyl ethyl ketone at 50 ° C. for 5 hours. More preferably, the mass swelling rate immediately after is 150% or less and the drop-off rate is 5% or less.

The residual ratio of the polymer elastic body containing the pigment here after the ultrafine fiber-generating fiber composed of the water-soluble polymer component and the poorly water-soluble polymer component is further thinned and further dyed (hereinafter referred to as the polymer elastic body) And may be abbreviated as the residual rate in the pigment extraction / dyeing process.), Which will be described later, but contains a pigment mixed in the same mass ratio of the elastic polymer and the pigment as in the case of producing a suede-like artificial leather. Using a polymer elastic water dispersion, a film is prepared, and the mass after heat treatment at 120 to 150 ° C. is set to W0. Thereafter, 90 ° C. hot water extraction treatment and dyeing step are performed in the same manner as in the case of producing a suede-like artificial leather. After the same treatment as that described above, the sample was dried and the mass (Ws) was measured. And the drop-off rate of the pigment and the polymer elastic body was calculated according to the following formula.
Residual rate in extraction and dyeing process of polymer elastic body and pigment (%) = 100 − [(W0−Ws) / W0] × 100
The hot water swelling rate at 130 ° C. of the polymer elastic body referred to here is described later. The mass after heat-treating the water-dispersed resin film at 120 to 150 ° C. is defined as W0 and immersed in hot water at 130 ° C. for 1 hour. Then, when the mass is W1, the swelling rate calculated according to the following calculation formula is used.
Hot water swelling ratio at 130 ° C. of polymer elastic body (%) = [(W1−W0) / W0] × 100
Moreover, the hot water drop-off rate at 130 ° C. of the polymer elastic body is described later. The mass after heat-treating the polymer elastic body cast film at 120 to 150 ° C. is defined as W0, and it is immersed in 130 ° C. hot water for 1 hour. When the mass after immersion and drying is defined as W2, it means the drop-off rate calculated according to the following formula.
Hydrothermal drop-off rate (%) of polymer elastic body at 130 ° C. = [(W0−W2) / W0] × 100

The residual rate of the sum of the pigment and the polymer elastic body after dyeing treatment (may be abbreviated as the residual rate in high-temperature dyeing) will be described later, but it is the same as that for producing suede-like artificial leather. A square cast film having a thickness of 50 ± 5 μm and a side of 10 cm is prepared using a pigment-containing polymer elastic water dispersion mixed at a mass ratio of the body and the pigment, and after heat treatment at 120 to 150 ° C., the mass (W0 ) Was measured. Then, after the 90 ° C. hot water extraction treatment as in the case of producing the suede-like artificial leather, the same treatment as that in the dyeing process, that is, the 130 ° C. high temperature dyeing treatment is performed. The neutralization process and the water washing process were performed, then the mass (W3) after drying at 120-150 degreeC was measured, and the residual rate of a pigment and a polymeric elastic body was computed according to the following formula.
Residual ratio of sum of pigment and polymer elastic body after dyeing treatment (residual ratio in high-temperature dyeing) (%) = 100 − [(W0−W3) / W0] × 100
On the contrary, the dropout rate in the high temperature dyeing is the dropout rate (%) in the high temperature dyeing = [(W0−W3) / W0] × 100.
With respect to the swelling rate and drop-off rate in the solvent treatment, the swelling rate and drop-off rate for each solvent are measured in the same manner at a predetermined solvent and temperature.

  In the present invention, the pigment for coloring the polymer elastic body is not a commonly used inorganic pigment, but sharpness, color development, and further, the mechanical performance and friction fastness associated with the addition of the pigment are minimized. It is necessary to use organic pigments and / or carbon black from the viewpoints of the above and the residual ratio of the elastic polymer containing the pigment to 95% or more. Since organic pigments are partially dissolved in organic solvents, it is necessary to use water-dispersed resins that do not use organic solvents in the present invention in which the polymer elastic body is colored with pigments containing organic pigments or organic pigments. It becomes. The water-dispersed resin here refers to a polymer elastic body dispersed in water or an aqueous solution substantially free of an organic solvent. In other words, the conventional method of impregnating and wet coagulating a polymer elastic body dissolved in an organic solvent partially dissolves and removes the organic pigment in the coagulation step and the organic solvent washing step. There is a problem that the color developability of the artificial leather is lowered and color blurring occurs, and further, the switching loss is increased, making it difficult to use organic pigments industrially. On the other hand, since inorganic pigments are hardly or completely insoluble in organic solvents, it can be considered that they are blended with polymer elastic bodies dissolved in organic solvents, but their color range is very narrow due to poor sharpness and color development. In addition, it is inferior in uniform mixing with the polymer elastic body and insufficiently impregnated, causing pigment spots to occur easily.Furthermore, the tensile properties, surface wear resistance, and friction fastness of suede artificial leather The effect of the present invention may not be obtained even if the polymer elastic body is colored only with an inorganic pigment.

  Further, it is preferable that the pigment is present in the polymer elastic body in a mixed and integrated manner, and the pigment is mainly embedded in the polymer constituting the polymer elastic body. The pigment mentioned here exists in the polymer elastic body in an integrated manner, and the pigment is mainly embedded in the polymer constituting the polymer elastic body. In this state, the pigment is substantially uniformly dispersed in the polymer elastic body. The addition amount of the pigment is preferably 0 to 10% by mass, and more preferably 0.01 to 5% by mass. When the pigment is less than 0.01% by mass, the resulting suede-like artificial leather may lack light fastness and color developability. On the contrary, when the pigment exceeds 10% by mass, the proportion of the pigment not embedded in the polymer elastic body increases, and the fastness such as friction fastness of the obtained suede-like artificial leather tends to decrease. In addition, the fiber-capturing performance of the polymer elastic body is reduced, and the tensile strength and surface wear resistance of the resulting suede-like artificial leather are reduced, and the pigment and the polymer elastic body fall off during the dyeing process. May increase, and it may be difficult to make the residual ratio of the elastic polymer containing the pigment 95% or more. In addition, when the color of the appearance required as the final product is light, the amount of pigment added to the inside of the polymer elastic body is preferably 0 to 1% by mass, and in the case of medium color, 1 to 2% by mass is preferable. In the case of a dark color, 2 to 5% by mass is preferable.

The average particle size of each pigment contained in the polymer elastic body of the present invention is preferably 0.05 to 0.6 μm. The average particle diameter here is an average particle diameter of the pigment in a state where the pigment is present in the elastic polymer, and does not indicate a primary particle diameter. In other words, pigments rarely exist in a primary particle size state, and generally in a state of aggregation called a primary aggregate, secondary aggregate, or secondary particle in which a large number of primary particle size pigments are aggregated. Exists. Further, the aggregation state is influenced by the type of the polymer elastic body, and the particle size of the pigment in the aggregation state is considered to dominate various performances. The average particle diameter in the present invention refers to an average particle diameter in an aggregated state called a structure, primary aggregate, secondary aggregate, or secondary particle in a polymer constituting the polymer elastic body.
When the average particle size of the pigment contained in the polymer elastic body is less than 0.05 μm, it is thought that the light hiding property and light fastness of the pigment itself are lowered. Of the obtained suede-like artificial leather, and the pigment tends to aggregate in the polymer elastic body fluid, making it difficult to uniformly disperse the pigment in the polymer elastic body fluid. There is a tendency to develop coloring spots and color spots. On the contrary, when the average particle size of the pigment contained in the polymer elastic body exceeds 0.6 μm, it becomes difficult for the pigment to be embedded in the polymer constituting the polymer elastic body. There is a tendency that the fastness such as friction fastness of the substrate tends to be inferior, and the pigment and the polymer elastic body drop off in the extraction process and the dyeing process, and the residual ratio of the polymer elastic body containing the pigment is 95% or more. May be difficult. Furthermore, when the polymer elastic body and the pigment are blended, the pigment tends to settle, the impregnation of the polymer elastic body containing the pigment becomes insufficient, and colored spots and color spots of the suede artificial leather are generated. Tend. The average particle diameter of the pigment is particularly preferably 0.1 to 0.5 μm. The average particle size and dispersion of the pigment contained in the polymer elastic body of suede-like artificial leather was confirmed by observing the cross-section and surface of the suede-like artificial leather with a scanning or transmission electron microscope. it can.

  The pigment to be contained in the polymer elastic body of the present invention includes, for example, phthalocyanine, anthraquinone, quinacridone, dioxazine, isoindolinone, isoindoline, indigo, quinophthalone, diketopyrrolo as organic pigments. Examples thereof include condensed polycyclic organic pigments such as pyrrole, perylene, and perinone, and insoluble azo such as benzimidazolone, condensed azo, and azomethine azo. Carbon black includes channel black, furnace black, samar black, etc., but the carbon black used in the present invention does not limit the type of carbon black itself. One or more of these organic pigments and carbon black are contained in the fiber. An inorganic pigment may be used in combination as long as the effects of the present invention are not hindered, and examples thereof include titanium oxide, red pepper, chrome red, molybdenum red, resurge, ultramarine, and iron oxide. In particular, the resulting suede-like artificial leather has excellent sharpness, color development, wide color tone, light fastness, friction fastness and surface wear resistance. Polycyclic organic pigments, phthalocyanine-based and insoluble azo pigments are particularly preferred. Condensed polycyclic organic pigments, phthalocyanine-based and insoluble azo pigments are composed of only condensed polycyclic organic pigments, phthalocyanine-based or insoluble azo-based pigments. Particularly preferred examples include pigments mainly composed of pigments and used in combination with carbon black, titanium oxide, or the like as required by color tone or the like. In applications that require high light resistance, such as car seats, it is desirable to avoid using pigments that are highly light-resistant.

  In the present invention, a water-dispersed resin diluted with a liquid such as water that is a non-solvent for the polymer elastic body and a liquid such as water that is a non-solvent for the pigment are diluted with a liquid. It is preferable to use a water-dispersed pigment in that the dispersibility of the pigment in the polymer elastic body is good. Further, both the water-dispersed resin and the water-dispersed pigment may be dispersed in a nonionic system, an anionic system, or a combination system thereof. This is preferable in that the blended liquid has good stability, the pigment is uniformly dispersed in the polymer elastic body, and the pigment is easily embedded in the polymer elastic body. The dispersibility of the pigment in the polymer elastic body and the stability of the liquid mixture of the polymer elastic body and the pigment are such that the pigment is uniformly dispersed in the polymer elastic body and the pigment is mainly embedded in the polymer elastic body. It is preferable to confirm in advance that it will be wrapped.

Moreover, after impregnating the polymer elastic body aqueous solution, the polymer elastic body is solidified. Examples of the solidification method include known methods. For example, a method of heat-drying solidification by heat treatment, or a method of heat-sensitive coagulation by hot water treatment, steam treatment, or infrared treatment is preferable.
Further, in the present invention, a method of coagulating a polymer elastic body so that it can uniformly exist in the entire fiber entangled body by a known method such as adding a heat-sensitive gelling compound or a metal salt to the polymer elastic water dispersion. It is more preferable to add.
As a method of impregnating the inside of the fiber entangled body with the water-dispersed resin, a known method that can uniformly impregnate the fiber entangled body with the aqueous dispersion of the polymer elastic body may be adopted. Preferred examples include a method of adjusting the impregnation amount of the water-dispersed resin to an appropriate amount using a press roll or a doctor knife after dipping the entangled body, a method using a coat coating method with a metering pump, and the like.
The viscosity is preferably 1 to 200 cpoise, more preferably 2 to 100 cpoise, from the viewpoint of the impregnating property of the polymer elastic water dispersion.

  The mass ratio of the fiber entangled body and the polymer elastic body of the present invention is preferably in the mass range of polymer elastic body: extra fine fiber entangled body = 5: 95-40: 60, more preferably 10: 90-30. : 70. When the polymer elastic body is less than 5% by mass, the fiber entangled body cannot be sufficiently fixed, and the resulting suede-like artificial leather tends to be inferior in physical properties such as suede feeling, surface touch, and surface wear. On the other hand, when it exceeds 40% by mass, the resilience and resistance peculiar to the polymer elastic body are increased, and the texture and surface touch of the obtained suede-like artificial leather tend to be inferior.

After impregnating the fiber entanglement made of ultrafine fiber-generating fibers with an aqueous dispersion of a polymer elastic body, the extraction removal component is removed with an aqueous solution that is a non-solvent of the ultrafine fiber and the polymer elastic body and is a solvent of the extraction removal component Then, the ultrafine fiber generation type fiber is made ultrafine.
In particular, when extracting and removing, the extraction and removal components are removed with an aqueous solvent such as hot water to reduce the size of the ultrafine fiber-generating fiber from the viewpoint of environmental problems and the ability to reduce the dropping of the pigment contained in the elastic polymer. A method is needed. The hot water extraction temperature is preferably 60 to 100 ° C., more preferably 80 to 95 ° C., for reasons such as the amount of remaining PVA being 1% by mass or less.
If necessary, the thickness is adjusted to a desired thickness by pressure heating treatment or division treatment. Further, before or after the ultrafine fiber-generating fiber is made ultrafine, at least one surface may be subjected to raising treatment such as buffing to form an ultrafine fiber raised surface mainly composed of ultrafine fibers to form a suede-like artificial leather. If necessary, finishing treatment such as stagnation softening treatment and reverse seal brushing can be performed.

The perfluoroalkyl acrylate polymer of the present invention has the following formula (1) as a structural unit:
_{CH 2 = CX-COO-Y} -Rf (1)
(Wherein, X is H or CH ₃ group, Y is an alkylene group having 1 or more carbon atoms, —CH ₂ CH ₂ N (R) SO ₂ — [R is an alkyl group], or CH ₂ CH (OZ ) CH ₂ [Z represents hydrogen or acetyl group] group Rf represents a fluoroalkyl group having 3 to 21 carbon atoms [however, the alkyl group may contain oxygen]. It is a fluorine compound polymerized from a fluorine monomer (a) derived from an acrylate ester or an methacrylate ester containing an alkyl group. A preferred example is a compound obtained by copolymerizing one or more ethylenically unsaturated monomers copolymerizable with the fluorine-based monomer. Here, the at least one ethylenically unsaturated monomer (b) copolymerizable with the fluorine-based monomer (a) is not particularly limited, but ethylene, vinyl chloride, vinyl fluoride, halogenated vinyl styrene. , Α-methylstyrene, β-methylstyrene, (meth) acrylic acid and alkyl esters thereof, polyoxyalkylene, (meth) acrylate, (meth) acrylamide, diacetone (meth) acrylamide, diacetone (meth) acrylamide, N-methylol (Meth) acrylamide, vinyl alkyl ether, halogenated alkyl vinyl ether, vinyl alkyl ketone, butadiene, isoprene, chloroprene, glycidyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, aziridinyl (meth) acrylate, benzyl ( Examples include meth) acrylate, iso-theatatoethyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, maleic anhydride, polysiloxane-containing (meth) acrylate, and N-vinylcarbazole.

  The composition ratio of the fluorine-based monomer (a) and the ethylenically unsaturated monomer (b) copolymerizable with the fluorine-based monomer (a) is a / (a + b) = 40 to 95% by mass. preferable. By adjusting the copolymerization ratio of (a) / (b), it is possible to adjust the adhesion to the fiber, the film-forming property, the film strength, the water resistance, and the like. Further, a perfluoroalkyl urethane polymer into which a part of a polyurethane fluoropolymer is introduced may be used. The number average molecular weight is preferably in the range of tens of thousands to hundreds of thousands from the viewpoints of film formability, film strength, and water resistance.

Although the mechanism of the improvement effect by the perfluoroalkyl acrylate polymer in the present invention is not clear, it has a moderate slip effect and moderate fiber adhesion, so that the suede tone can be obtained while improving the fine fiber separation property. By reducing the frictional resistance of the artificial leather surface, the mechanical properties such as suede feeling, surface touch, denseness, fullness, and tearing strength can be improved. By reducing the water absorption, it is considered that the resulting suede-like artificial leather has an effect of reducing the falling off of the water-dispersed resin and ultrafine fibers due to rubbing in a wet state. In addition, the perfluoroalkyl acrylate polymer preferably has a film-forming property. By having the film-forming property, the inside of the ultrafine fiber bundle or between the ultrafine fiber bundles is appropriately bonded, and the hair is removed during dyeing or actual use. It is also considered that there is an effect of further suppressing the dropping of the water-dispersed resin. For this reason, the addition of perfluoroalkyl acrylate polymers is a polymer elasticity consisting of ultrafine fiber bundles made of ultrafine fiber-generating fibers with a water-soluble polymer component as one component and water-dispersed resin. It is considered to be particularly effective for suede-like artificial leather composed of the body. Furthermore, since a static electricity generally increases when a perfluoroalkyl acrylate polymer is applied, an antistatic agent is often used in combination, but in the present invention, a water-dispersed resin and a water-soluble polymer component are highly water-absorbing. Therefore, it is not necessary to use an antistatic agent in combination, and there is an unexpected effect that can prevent dye seepage and increase in water absorption due to the addition of the antistatic agent.
On the other hand, in the case of a perfluoroalkyl-based polymer that does not contain an acrylate group, the slip effect is too great, and the fiber adhesion and film-forming properties are inferior, making it difficult to achieve the object of the present invention.

The perfluoroalkyl acrylate polymer is preferably contained in an amount of 0.05 to 5% by weight in the inside of the ultrafine fiber bundle, the surface thereof, and the polymer elastic body. If it is less than 0.05% by weight, it is difficult to obtain an improvement effect, and it has a suede feeling, surface touch, denseness, and fullness similar to those of the natural leather targeted by the present invention, water resistance such as moisture-resistant fastness, Suede-like artificial leather excellent in mechanical properties such as tear strength cannot be industrially stably provided. On the other hand, when it exceeds 5% by weight, the texture becomes stiff and the static electricity tends to increase. More preferably, it is 0.2-4 mass%.
In addition, it is necessary that the perfluoroalkyl acrylate polymer is attached to the inside of the ultrafine fiber bundle, the surface thereof, and the polymer elastic body. Difficult to get. Accordingly, a preferred example is a method of providing a perfluoroalkyl acrylate polymer after extracting a water-soluble polymer component to generate ultrafine fibers and after applying a polymer elastic body. Specifically, the perfluoroalkyl acrylate polymer may be treated after applying the water-dispersed resin and further ultrafine-treating the ultrafine fiber-generating fiber, or after dyeing after the above-described treatment. preferable. Further, after the ultrafine fiber generating fiber is subjected to ultrafine treatment or dyeing treatment, a perfluoroalkyl acrylate polymer may be further applied in a wet state without drying the substrate. The method for applying the perfluoroalkyl acrylate polymer is not particularly limited as long as it adheres to the inside of the ultrafine fiber bundle, the surface thereof, and the polymer elastic body. The perfluoroalkyl acrylate polymer is preferably attached to the entire substrate. The attachment method is not particularly limited, but it is possible to use a known application method such as a dip nip method or a coating method. From the viewpoint of fixing the perfluoroalkyl acrylate polymer to the substrate after treatment, 100 to 180 It is preferable to heat-treat at a temperature of 120 ° C., more preferably 120 to 160 ° C. Moreover, you may give the surface layer side by a well-known method, such as the gravure method, from the surface (napped) layer of suede artificial leather.

  The suede-like artificial leather of the present invention preferably has a water absorption rate of 5 to 80% when immersed in water at 23 ° C. for 24 hours. By setting the water absorption rate to 5 to 80%, it is possible to reduce the dropping of the water-dispersed resin and fibers due to rubbing of the obtained suede-like artificial leather in a wet state. More preferably, it is 10 to 60%. When the water absorption is less than 5%, static electricity tends to increase. When an ultrafine fiber generating fiber made of a water-dispersed resin or a water-soluble polymer component is used, the water absorption rate tends to increase. To reduce the water absorption rate to 5 to 80%, a perfluoroalkyl acrylate polymer is used. In an amount of 0.05 to 5% by weight, and the residual ratio of the water-soluble polymer component is 1% or less.

In addition, the residual rate of the water-soluble polymer in the present invention can be determined as follows.
[Remaining rate of water-soluble polymer (%)]
The fiber entangled bodies used in the following formulas (1) to (3) are all prepared by measuring a plurality of samples obtained by the same composition and the same technique.
(1) The absolutely dry mass of the fiber entangled body before the extraction treatment is Ag, and this fiber entangled body is treated for 5 hours in a 120 ° C. hot water bath using a liquid dyeing machine, 5 times. The absolute dry mass of the fiber entangled body after the hot water treatment is defined as Bg. Using A and B, the extraction rate when completely extracted is calculated by the following equation.
Complete extraction rate X (%) = 100 × (A−B) / A
(2) When the absolute dry mass before the extraction process of another sample same as that used in (1) is Cg, the extraction process is performed under arbitrary conditions, and the absolute dry mass after the extraction process is Dg The extraction rate Y is expressed by the following equation.
Extraction rate Y (%) under arbitrary extraction conditions = 100 × (C−D) / C
(3) Using the above complete extraction rate X and the sample extraction rate Y under any extraction conditions, the residual rate C of the water-soluble polymer component is calculated by the following equation.
Residual rate of water-soluble polymer component Z (%) = XY
In this way, it is also possible to calculate the residual ratio of the water-soluble polymer component after the dyeing treatment.

Further, as described above, by attaching the perfluoroalkyl acrylate polymer to the inside of the ultrafine fiber bundle and to the surface and the polymer elastic body, in addition to having the above-described improvement effect, the buffing property is improved and the dyeing is performed. It is thought that there is also a softening effect as a softening agent.
In the perfluoroalkyl acrylate polymer to be imparted, unless it impairs the characteristics of the present invention, a penetrant, a thickener, an antioxidant, an ultraviolet absorber, a film-forming aid, a polymer elastic body, a softener, a lubricant, An antifouling agent, a fluorescent agent, an antifungal agent, a flame retardant, a water-soluble polymer compound such as polyvinyl alcohol and carboxymethyl cellulose, a dye, and a pigment may be appropriately contained.

In the present invention, the density of the obtained suede-like artificial leather is preferably 0.40 to 0.85 g / cm ³ . When the density is less than 0.40 g / cm ³ , it becomes difficult to obtain a natural leather-like texture, and when the density is greater than 0.85 g / cm ³ , the softness tends to be inferior. Preferably, it is the range of 0.45-0.80 g / cm < ³ >. The density of the conventional artificial leather is in the range of 0.3 to 0.45 g / cm ³ , and the artificial leather of the present invention has a high density, and this high density is a texture that closely resembles natural leather to the artificial leather of the present invention. It brings a sense of fulfillment and drape.

  The heat-fastness of the artificial leather substrate (not dyed) comprising the polymer entangled body and pigment containing the fiber entangled body of the present invention is grade 3 or higher under the heat treatment conditions at 130 ° C. for 100 hours. Is preferred. Moreover, it is preferable that it is a 3rd grade or more also on the conditions heat-processed at 110 degreeC for 200 hours. In addition to obtaining a suede-like artificial leather with excellent heat fastness even after dyeing, there is little thermal deterioration in the dyeing process, and even when a small amount of polymer elastic body drops off, there is little contamination on the dyeing machine, The dyeing process is excellent.

The suede-like artificial leather of the present invention can be provided with a resin layer as necessary to obtain an artificial leather with a tone with silver or a tone with semi-silver. Alternatively, the surface layer can be melted to form a resin layer by heating the surface and pressing against a smooth surface. As the resin applied to the surface, an elastic polymer typified by polyurethane or acrylic is preferably used. Further, the coloring treatment may be performed using a small amount of dye or a small amount of pigment. Further, if necessary, the artificial leather of the present invention is used as an upper layer, and a knitted fabric or a knitted fabric is bonded together as a lower layer, or the raised nail artificial leather of the present invention is used as an upper layer, and the napped-toned artificial leather A layer made of a different kind of fiber from the fibers constituting the layer may be bonded to form a lower layer.
As long as the characteristics of the present invention are not impaired, the polymer elastic body applied to the surface is a penetrant, a thickener, an antioxidant, an ultraviolet absorber, a film-forming aid, a heat-sensitive gelling agent, a softening agent, a lubricant, an anti-proofing agent. It may contain a soiling agent, a fluorescent agent, an antifungal agent, a flame retardant, a water-soluble polymer compound such as polyvinyl alcohol and carboxymethyl cellulose, a dye, and the like as appropriate.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited at all by these Examples. Evaluations such as performance measurement described in the following examples and comparative examples were performed by the following methods.

[Measurement of wet friction fastness]
According to JIS L0801, it measured in the wet state and evaluated by class determination.

[Tear strength measurement]
A test piece of 10 cm long × 4 cm wide is cut out, and a 5 cm cut is made in the center of the short knives at right angles to this side, and each section is sandwiched between chucks and teared at a speed of 10 cm / min with a tensile tester. The maximum tearing load is obtained, and the value obtained by dividing by the basis weight of the test piece obtained in advance is taken as the tear strength value. And it represents with the average value of three test pieces.

[Average particle diameter of water-dispersed pigment]
Measured by the dynamic light scattering method using “ELS-800” manufactured by Otsuka Chemical Co., Ltd., analyzed by the cumulant method (described in “Colloid Chemistry Vol. IV Colloid Chemistry Experimental Method” published by Tokyo Chemical Doujinsha) The average particle size of the dispersed pigment was measured.

[Average particle size and distribution of pigment in the elastic polymer]
The cross section of the suede-like artificial leather dyed with osmium oxide was observed with a scanning electron microscope “S-2100 Hitachi Scanning Electron Microscope” (at a magnification of 2000 to 10,000 times) at 10 or more locations, and the pigment in the polymer elastic body was observed. Average particle size and distribution were measured.

[Residual rate in extraction and dyeing process of elastic polymer and pigment]
The pigment residual rate of the pigment contained in the polymer elastic body is the same as that for producing a suede-like artificial leather, using a pigment-containing polymer elastic water dispersion mixed in a mass ratio of the polymer elastic body and the pigment, A square cast film having a thickness of 50 ± 5 μm and a side of 10 cm was prepared, heat-treated at 120 to 150 ° C., and then the mass (W0) was measured. Thereafter, as in the case of producing a suede-like artificial leather, a treatment equivalent to the 90 ° C. hot water extraction treatment and the dyeing step, that is, a 130 ° C. high temperature dyeing treatment, followed by sodium hydroxide 6 g / l, Techlite (Tokai Denka Kogyo Co., Ltd.) Alkali reduction washing treatment at 6 g / l at 70 ° C. for 50 minutes, neutralization treatment at 60 ° C. for 10 minutes with 1 g / l acetic acid, water washing, and then drying at 120 to 150 ° C. . The mass (Ws) after standing for 2 hours was measured, and the dropout rate of the pigment and the elastic polymer was calculated according to the following formula.
Residual rate in extraction and dyeing process of polymer elastic body and pigment (%) = 100 − [(W0−Ws) / W0] × 100

[Measurement of hot water swelling rate and drop-off rate of water-dispersed resin film at 130 ° C.]
After heat-treating a square polymer elastic cast film having a thickness of 50 ± 5 μm and a side of 10 cm at 120 to 150 ° C., the mass (W0) was measured. Then, after being immersed in 130 degreeC hot water for 1 hour, the sample was taken out, the mass (W1) was measured immediately, and the swelling rate was calculated according to the following formula.
130 ° C. hot water swelling ratio of polymer elastic body (%) = [(W1-W0) / W0] × 100
Regarding the drop-off rate, the mass (W2) after drying was measured, and the drop-off rate was calculated according to the following formula.
130 ° C. hot water drop-off rate of polymer elastic body (%) = [(W0−W2) / W0] × 100

[Measurement of swelling rate and drop-off rate of water-dispersed resin film with 50 ° C. methyl ethyl ketone]
After heat-treating a square polymer elastic cast film having a thickness of 50 ± 5 μm and a side of 10 cm at 120 to 150 ° C., the mass (W0) was measured. Then, after immersing in 50 degreeC methyl ethyl ketone for 5 hours, the sample was taken out, the mass (Wm) was measured immediately, and the swelling rate was calculated according to the following formula.
50 ° C. methyl ethyl ketone swelling ratio (%) of polymer elastic body = [(Wm−W0) / W0] × 100
Regarding the drop-off rate, the mass (Wn) after drying was measured, and the drop-off rate was calculated according to the following formula.
50 ° C. methyl ethyl ketone drop-off rate of polymer elastic body (%) = [(W0−Wn) / W0] × 100

[Measurement of residual rate and drop-off rate in high-temperature dyeing]
After heat-treating a square polymer elastic body (including pigment) cast film having a thickness of 50 ± 5 μm and a side of 10 cm, the mass (W0) was measured. Thereafter, after high-temperature dyeing at 130 ° C. for 60 minutes, it was subsequently subjected to alkaline reduction washing treatment at 70 ° C. for 50 minutes with 6 g / L of sodium hydroxide and 6 g / L of Techlite (manufactured by Tokai Denka Kogyo Co., Ltd.), and further 1 g of acetic acid. / L at 60 ° C. for 10 minutes and then washed with water. Thereafter, the mass (W3) after drying at 120 to 150 ° C. and leaving for 2 hours was measured, and the residual ratio was calculated according to the following formula. The dye concentration was 2% by mass or less based on the film.
Residual rate in high-temperature dyeing (%) = 100 − [(W0−W3) / W0] × 100
Dropout rate at high temperature dyeing (%) = [(W0−W3) / W0] × 100

[Measurement of amount of residual PVA]
After immersing the suede-like artificial leather in HFIP (hexafluoroisopropyl alcohol) and dissolving the fiber constituents and the elastic polymer component, etc., in the suede-like artificial leather with a 500 MHz proton NMR (JEOL GX-500) device. The amount of PVA occupied was quantified by mass ratio. If the polymer elastic body does not dissolve in HFIP, the mass ratio of the amount of PVA in the component excluding the polymer elastic body dissolved in HFIP is measured, and separately, the mass of the polymer elastic body component that does not dissolve in HFIP. The amount of PVA in the suede-like artificial leather can be determined by measuring the mass ratio of the polymer elastic body component in the suede-like artificial leather.

[Melting point of thermoplastic resin]
Using DSC (TA3000, Mettler), 10 mg sample, in nitrogen, heated to 250 ° C at a heating rate of 10 ° C / min, cooled to room temperature, and then increased again to 250 ° C at a heating rate of 10 ° C / min. The endothermic peak shown when warmed was measured and determined.

[Water absorption rate]
A test piece having a length of 15 cm and a width of 15 cm is prepared, and the weight (W0) before water immersion is measured. After immersing the test piece in 23 ° C. water for 24 hours, water drops excessively adhered to the surface were gently wiped off with filter paper, the weight after immersion (W1) was measured, and the water absorption was calculated according to the following formula.
Water absorption rate (%) = [(W1-W0) / W0] × 100

Polyvinyl terephthalate (melting point: 235 ° C.) containing 8% by mass of isophthalic acid added with 3.0% by mass of carbon black is an island component, contains 10 mol% of ethylene units, has a saponification degree of 98.4 mol% and a melting point of 210 ° C. An alcohol copolymer (Exeval manufactured by Kuraray Co., Ltd.) was used as a sea component, and 64 islands of islands with a mass ratio of sea / island = 30/70 were composite-spun, and then drawn to draw a single yarn fineness of 5.5 dtex. Fiber was obtained. The fiber was crimped, cut to 51 mm, and carded to produce a short fiber web having a basis weight of 120 g / m ² .

Next, 36 islands of sea-island fiber with the above polymer composition and sea / island = 40/60 are compound-spun, and a fiber with a single yarn fineness of 2.3 dtex is drawn by a roller plate method under normal conditions. Got. A plain woven fabric having a weave density of 105 × 84 yarns / inch and a basis weight of 120 g / m ² was prepared under the condition of a twist number of 500 T / m.

After laminating the above two webs and a plain woven fabric, needle processing was performed under conditions of 1500 punch / cm ² , 20% area shrinkage due to dry heat shrinkage at 190 ° C., and heat-pressing at 175 ° C., basis weight 501 g / cm ² , apparent A fiber entangled body having a density of 0.75 g / cm ³ and a thickness of 0.70 mm was obtained.

  Next, Sanyo pigment water-dispersed pigment (carbon black with an average particle size of 0.25 μm / organic blue pigment with an average particle size of 0.2 μm / organic red pigment with an average particle size of 0.2 μm = 5/2/1; solid Measurement of polyurethane and film (fraction ratio) and acrylic-urethane composite resin (composition: acrylic / urethane ratio = 60/40, polyurethane component is ether / polycarbonate / 4,4′-dicyclohexylmethane diisocyanate nitrogen content 3.5%) : 130 ° C. hot water swelling rate = 10%, 130 ° C. hot water dropping rate 1%, 50 ° C. methyl ethyl ketone swelling rate 110%, 50 ° C. methyl ethyl ketone dropping rate 2%, dropping rate at high temperature dyeing = 1%, polymer elastic body And pigment remaining rate in the extraction / dyeing process = 99%), silicone-based heat-sensitive gelling agent (clouding point of 30% aqueous solution at 50 ° C.), sodium sulfate, pigment / heat-sensitive Mixed with a solid content mass ratio of Le agent / sodium sulfate / composite resin = 2 / 0.3 / 0.2 / 100 to give a concentration of 35% by weight of water dispersible resin.

  Next, using a lip coater equipment (Hipano Techseed's lip direct method) as an impregnation equipment, water dispersion resin is impregnated so that the mass ratio of the polymer elastic body / fiber entanglement after ultrafine fiber is 20/80 did. After impregnating the water-dispersed resin, it was pre-dried with an infrared heating device and then dried with a hot air dryer at 150 ° C. for 5 minutes. Thereafter, the unimpregnated portions of 5 cm on both sides were cut, the polyvinyl alcohol copolymer component was extracted with hot water at 90 ° C., and then 4% by weight of a perfluoroalkyl acrylate polymer [Nikka Chemical Co., Ltd. NK GUARD NDN-2000] was impregnated, squeezed and dried at 130 ° C. to obtain an artificial leather base. The obtained artificial leather substrate was an artificial leather substrate having a good appearance without wrinkles and elongation, and having a uniform leather-like texture and excellent physical properties. The adhesion rate of the perfluoroalkyl acrylate polymer was 1.8% by mass in the solid form, and the cross section of the artificial leather substrate was observed with an electron microscope. The inside of the ultrafine fiber bundle, the surface of the ultrafine fiber bundle, and the polymer elasticity I could see it attached to my body. In addition, the single fibers constituting the woven fabric had random fine crimps.

Next, after brushing at least one surface, buffing treatment was performed and then Sumikaron UL dye (manufactured by Sumitomo Chemical Co., Ltd.) Yellow 3RF 1.5owf%, Red GF 1.5owf%, Blue GF 4.0owf%, anti After fading MC-500 (manufactured by Meisei Chemical Co., Ltd.), 1 owf%, Disper TL (manufactured by Meisei Chemical Co., Ltd.) 1 g / L, high-pressure dyeing at 130 ° C., followed by sodium hydroxide 6 g / L, Techlite (Tokai Denka Kogyo Co., Ltd.) Company) 6g / L at 70 ° C for 50 minutes with alkali reduction, neutralized with acetic acid 1g / L at 60 ° C for 10 minutes, then washed with water, dried at 130 ° C, and reverse seal brushing Finishing treatment was performed. The resulting black suede-like artificial leather had a short fiber fineness of 0.067 dtex, a woven / knitted single fiber fineness of 0.043 dtex, and a density of 0.60 g / cm ³ . Black with good color development, excellent suede feeling, surface touch and drape, excellent tear strength of 1.1kg / 100g, wet friction fastness 4th class, and less sticking of dirt due to less generation of static electricity Met. The water absorption when immersed in water was 14%, and the residual polyvinyl alcohol copolymer ratio was 0.1% by mass.

(Change of the amount of perfluoroalkyl acrylate polymer)
Implementation was performed except that the perfluoroalkyl acrylate polymer of Example 1 was changed to NDN-390E manufactured by Nikka Chemical Co., Ltd., and the substrate for artificial leather was treated with a 5.0% by mass solution to adhere 2.3% by mass. The same operation as in Example 1 was performed. As a result, the obtained color developability was excellent, the tear strength was 1.2 kg / 100 g, the wet friction fastness was excellent, and the texture such as suede feeling and drape was excellent. The water absorption when immersed in water was 11%, and the residual polyvinyl alcohol copolymer ratio was 0.1% by mass.

(Change of carbon black addition amount, fineness and color of short fibers)
The amount of carbon black added to the short fiber of Example 1 was 0.4% by mass, the single yarn fineness was 3 dtex, sea / island = 40/60, and a water-dispersed pigment made of Sanyo Dye (carbon black / average particle size of 0.25 μm / Yellow 3RF 0 of Sumikaron UL dye (manufactured by Sumitomo Chemical Co., Ltd.) as a disperse dye, organic blue pigment with an average particle diameter of 0.2 μ / organic red pigment with an average particle diameter of 0.2 μ = 1/15/10; solid content ratio) .5owf%, Red GF 1.0owf%, Blue GF 3.5owf%, Antifade MC-500 (Madesei Chemical), 1owf%, Disper TL (made by Meisei Chemical) 1g / L The other operations were the same as in Example 1. As a result, the obtained artificial leather of navy blue tone has a short fiber fineness of 0.031 dtex, a density of 0.62 g / cm ³ , excellent color development, tear strength of 1.3 kg / 100 g, and wet friction fastness 4 It was excellent in grade and excellent in texture such as suede feeling and drape. The water absorption when immersed in water was 17%, and the residual polyvinyl alcohol copolymer ratio was 0.1% by mass.

(Change of the amount of perfluoroalkyl acrylate polymer)
The same operation as in Example 1 was performed, except that the 20% by mass solution of the perfluoroalkyl acrylate polymer used in Example 1 was impregnated after dyeing to adhere 8% by mass. The obtained suede-like artificial leather had a tear strength of 1.0 kg / 100 g and a wet friction fastness of 4-5 grade, but the texture was slightly hard, but there was no problem in practical use. In addition, the obtained suede-like artificial leather was prone to static electricity and easily adhered to dirt such as dust. The water absorption when immersed in water was 4%.

Comparative Example 1 (no perfluoroalkyl acrylate polymer treatment)
The same operation as in Example 1 was performed except that the treatment of the perfluoroalkyl acrylate polymer performed in Example 1 was not performed. The obtained suede-like artificial leather was slightly inferior to the suede feeling with a rough surface touch, inferior to tear strength 0.9 kg / 100 g and wet friction fastness 2-3 grade. The water absorption when immersed in water was 120%.

Comparative Example 2 (Change of adhesion state of perfluoroalkyl acrylate polymer)
The same operation as in Example 1 was performed, except that the treatment of the perfluoroalkyl acrylate polymer performed in Example 1 was performed before impregnation with the water-dispersed resin. Although the perfluoroalkyl acrylate-based polymer was adhered between the ultrafine fiber bundles, it was not adhered to the inside of the ultrafine fiber bundle or the polymer elastic body. The obtained suede-like artificial leather had a rough surface feeling with a rough surface touch, and was inferior with a tear strength of 0.9 kg / 100 g and a wet friction fastness of 3rd grade. The water absorption rate when immersed in water was 110%.

Comparative Example 3 (use of water repellent other than perfluoroalkyl acrylate polymer)
The same operation as in Example 1 was performed except that the perfluoroalkyl acrylate polymer used in Example 1 was changed to a liquid dimethylsiloxane polymer [POLON-MNS manufactured by Shin-Etsu Chemical Co., Ltd.]. The obtained suede-like artificial leather had a rough surface and hair loss occurred. The tear strength was 1.1 kg / 100 g, the wet friction fastness was grade 3 and the water absorption when immersed in water was 20%. .

Comparative Example 4 (use of water repellent other than perfluoroalkyl acrylate polymer)
The same operation as in Example 1 was performed except that the perfluoroalkyl acrylate polymer used in Example 1 was changed to a Teflon (registered trademark) fluoropolymer [Teflon (registered trademark) leather protector manufactured by DuPont]. . The obtained suede-like artificial leather had a rough surface and hair loss occurred. Also, the tear strength was 1.2 kg / 100 g, the wet friction fastness was 3rd, and the water absorption when immersed in water was 6%. .

The polymer elastic body used in Example 1 is a urethane resin (component: polyalkylene glycol / ether / polycarbonate / 4,4′-dicyclohexylmethane diisocyanate-based polyurethane with a nitrogen content of 3.0%, measurement of film: 130 ° C. Hot water swelling rate = 8%, 130 ° C. hot water drop-off rate 1%, 50 ° C. methyl ethyl ketone swelling rate 90%, 50 ° C. methyl ethyl ketone drop-off rate 4%, high-temperature dyeing drop-off rate = 2%, polymer elastic body and pigment Residual rate in extraction / dyeing process = 98%), and the same operation as in Example 1 was performed except that a silicone-based heat-sensitive gelling agent (cloud point of 30% aqueous solution at 50 ° C.) and sodium sulfate were not added. . The obtained suede-like artificial leather had excellent color development, excellent suede feeling, surface touch and drape, excellent tear strength of 1.2 kg / 100 g, and wet friction fastness grade 4. The water absorption when immersed in water was 20%, and the residual polyvinyl alcohol copolymer ratio was 0.1% by mass.

Claims (7)

It is composed of a fiber entangled body made of ultrafine fiber bundles and a polymer elastic body. The following (1) ultrafine fiber bundles make ultrafine fiber generation type fibers made of a water-soluble polymer component and a poorly water-soluble polymer component ultrafine, The fiber fineness is composed of fibers having a 0.0003 to 0.4 dtex,
(2) The resin constituting the polymer elastic body is a water-dispersed resin,
(3) A suede-like artificial leather, wherein the perfluoroalkyl acrylate polymer is attached to the inside of the ultrafine fiber bundle, the surface thereof, and the polymer elastic body. The suede-like artificial leather according to claim 1, wherein the perfluoroalkyl acrylate polymer is adhered to 0.05 to 5% by mass. The suede-like artificial leather according to claim 1 or 2, wherein the water absorption is 5 to 80%. The resin constituting the polymer elastic body is a water-dispersed resin composed of at least one of polyurethane, acrylic and polyurethane-acrylic composite resin, and has 0.1 to 10% by mass of pigment. The suede-like artificial leather according to claim 1. 5. The residual ratio of the polymer elastic body containing a pigment is 95% or more after ultrafine fiber-generating fibers composed of a water-soluble polymer component and a poorly water-soluble polymer component are further finely dyed. The suede-like artificial leather described in 1. The suede-like artificial leather according to any one of claims 1 to 5, wherein the polymer elastic body has a weight swelling ratio of 20% or less and a drop-off ratio of 3% or less in 130 ° C hot water. The suede-like artificial leather according to any one of claims 1 to 6, wherein the polymer elastic body has a weight swelling ratio of 150% or less and a dropout ratio of 5% or less when treated with 50 ° C methyl ethyl ketone.