JP2006112006A - Nonwoven fabric for flame-retardant leather-like sheet base material and flame-retardant leather-like sheet base material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nonwoven fabric for flame-retardant leather-like sheet base materials and the flame-retardant leather-like sheet base material. <P>SOLUTION: The nonwoven fabric for flame-retardant leather-like sheet base materials is obtained by successively laminating (A) a nonwoven fabric mainly composed of a polyester ultrafine fiber (a) bundles not containing a flame-retardant component, (B) a nonwoven fabric mainly composed of a flame-retardant copolyester ultrafine fiber (b) bundles containing a phosphorus-containing compound and (C) a woven or knitted fabric mainly composed of a flame-retardant copolyester containing a phosphorus-containing compound and mutually penetrating and entangling a fiber constituting the nonwoven fabric (A) with a fiber constituting the nonwoven fabric (B) through the woven or knitted fabric (C) and compositing and integrating these components (A) to (C). In the nonwoven fabric, the ultrafine fiber-forming type fiber constituting the nonwoven fabric (B) does not substantially arrive at the surface on opposite side of the surface contacting with the woven or knitted fabric (C) of the nonwoven fabric (A), but the ultrafine fiber-forming type fiber constituting the nonwoven fabric (A) arrives at the surface on the opposite side of the surface contacting with the woven or knitted fabric (C) of the nonwoven fabric (B). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a non-woven fabric for a flame-retardant leather-like sheet substrate and a flame-retardant leather-like sheet substrate comprising the nonwoven fabric. More specifically, the present invention is a flame-retardant leather-like material that has a soft and high-quality feeling, excellent surface strength such as abrasion resistance and peel strength, and excellent shape stability. The present invention relates to a nonwoven fabric for sheet base material and a flame-retardant leather-like sheet base material. The flame-retardant leather-like seat base material of the present invention and the leather-like seat using the same are particularly preferably used as a veneer for interior products such as vehicle seats, cushion seats, sofas, and chairs by taking advantage of the above-described characteristics. Used.

  Leather-like sheets are conventionally used in various applications such as interiors, clothing, shoes, bags, gloves, and vehicular seats. Among them, in the field of interior furniture such as railcar seats, automobile seats, aircraft seats, ship seats such as ship seats, cushion seats, sofas and chairs, good surface wear resistance and From the viewpoint of safety, there is a strong demand for a leather-like sheet that has high quality and form stability that does not cause elongation or sag or wrinkle even after long-term use, and from the viewpoint of safety.

The leather-like sheet is divided into two types: a leather-like sheet with a silver surface formed by a wet or dry method on the surface of a leather-like sheet base material, and a suede-like leather-like sheet with a brushed surface of the leather-like sheet base material. Although roughly classified, the leather-like sheet base material that forms the base of any leather-like sheet generally has a structure in which an elastic polymer is contained in the entangled space of the nonwoven fabric.
As a method of imparting flame retardancy to such a leather-like sheet base material or a leather-like sheet based thereon, (1) a leather-like sheet base material or a silver-finished leather-like sheet formed using the same After the suede-like leather-like sheet is manufactured, a post-processing method impregnating with a flame retardant, (2) a method of adhering a flame-retardant woven or knitted fabric to the back surface of the leather-like sheet substrate, and (3) a flame-retardant fine particle A method for producing a leather-like sheet substrate using fibers produced by addition, (4) a flame retardant added as an elastic polymer contained in the entangled space of the nonwoven fabric constituting the leather-like sheet substrate The method used is generally adopted.

  However, in the case of the post-processing method (1) described above, when the leather-like sheet base is formed of an ultrafine fiber bundle, even if the flame retardant is in the form of fine particles, it can penetrate into the ultrafine fiber bundle. It is extremely difficult, and most of the flame retardant is present on the outside of the ultrafine fiber bundle and on the outer surface of the elastic polymer. As a result, the appearance of the leather-like sheet is deteriorated by being soiled by the flame retardant, and the flame retardant is likely to drop off, making it difficult to obtain a durable flame retardant effect. In addition, in order to prevent the flame retardant from dropping off, there is also a method of adding a flame retardant into the binder resin liquid and impregnating it into a leather-like sheet base material or leather-like sheet. It is difficult to penetrate the flame retardant into the inside of the ultrafine fiber bundle, but rather the flame retardant effect is greatly reduced because the surface of the flame retardant is covered with the binder resin. In addition, the impregnation of the binder resin tends to cause defects such as the loss of flexibility of the leather-like sheet base material or the leather-like sheet and the inability to obtain a sufficient raised state.

  In addition, as the method of (2) above, there is a method in which a flame retardant sheet material obtained by applying a flame retardant such as a phosphorus compound or a halogen compound to a woven or knitted fabric is bonded to the back surface of a leather-like sheet substrate or a leather-like sheet. Although generally adopted, by attaching a flame retardant sheet material, the soft and high-quality texture peculiar to the leather-like sheet is easily impaired.

  Further, the fiber used in the method (3) is generally produced by adding flame retardant fine particles to a fiber-forming polymer such as polyamide or polyester and melt spinning, but it is difficult to perform the spinning at the time of melt spinning. From the viewpoint of the stability of the flame retardant and the polymer, there are limitations on the setting of the spinning temperature, the selection of the polymer and the flame retardant, etc. Moreover, yarn breakage is likely to occur, and there is also a problem in terms of productivity. In addition, the fiber produced by adding the flame retardant fine particles has a large decrease in fiber properties, and when such a fiber is used as a leather-like sheet base material for a suede-like leather-like sheet, the wear resistance strength is greatly reduced. To do. Further, when it is used as a leather-like sheet base material for a silver-finished leather-like sheet, the peel strength of the silver surface is lowered, and a leather-like sheet having practical value cannot be obtained.

  In the case of the above method (4), it is generally sufficient to add only the elastic polymer contained in the nonwoven fabric without adding the flame retardant to the fibers forming the nonwoven fabric in the leather-like sheet base material. Flame retardant effect cannot be obtained. In this method, if the amount of the flame retardant added to the elastic polymer is increased in order to increase the flame retardant effect, the texture of the leather-like sheet becomes hard and the sense of quality is lost.

  For the purpose of solving the problems of the prior art as described above, a fiber substrate is formed using a fiber comprising a flame retardant polyester copolymerized with a phosphorus compound or a halogen compound, and a bromine-containing modified urethane compound is formed on the fiber substrate. A microporous fiber substrate is formed by impregnating with a flame retardant polyurethane solution containing selenium and wet coagulating, and a polycarbonate polyurethane adhesive layer containing antimony trioxide and a bromine-containing modified urethane compound is formed on the microporous fiber substrate. Synthetic leather in which a specific polycarbonate polyurethane film layer is laminated has been proposed (see Patent Document 1). However, since this synthetic leather uses a bromine-containing modified urethane compound containing halogen as a flame retardant polyurethane to be impregnated into a fiber base and a polyurethane as an adhesive, it is easy to generate harmful gases during incineration. Undesirable from the viewpoint of environmental pollution. In addition, this synthetic leather is formed by using a flame retardant polyester fiber copolymerized with a phosphorus compound or a halogen compound or a fiber added with a halogen flame retardant for the entire fiber substrate constituting the base microporous fiber substrate. However, since these flame-retardant fibers are not strong enough, the surface strength such as wear resistance and peel strength tends to decrease.

In addition, a non-woven fabric is formed from a flame-retardant ultrafine fiber made of a flame-retardant copolyester obtained by copolymerizing an organic phosphorus compound, and a polymer elastic body containing aluminum hydroxide is contained inside the non-woven fabric (patent document) 2) is also proposed, but the flame-retardant ultrafine fiber made of a flame-retardant copolyester obtained by copolymerizing an organophosphorus compound is not sufficient in strength, and therefore has surface strength such as wear resistance and peel strength. There is a disadvantage of being inferior. In addition, a nonwoven fabric composed of polyester ultrafine fibers that do not contain a flame retardant imparting component on the surface layer, and a nonwoven fabric composed of ultrafine fibers composed of a copolymerized polyester copolymerized with a phosphorus-containing compound are laminated on the back layer. A method (see Patent Document 3) in which a polymer elastic body containing aluminum hydroxide is included has been proposed. In this method, the surface layer is composed only of ordinary polyester ultrafine fibers, so that sufficient surface strength and flame retardancy can be secured. And sufficient form stability is not ensured in terms of wrinkles. Also, the surface layer is made of ultra-thin thermoplastic synthetic fiber of 0.5 dtex or less, and the woven or knitted fabric and / or the back layer uses phosphorus copolymer thermoplastic synthetic fiber, and contains a water-based polyurethane resin. Patent gazettes relating to leather-like sheets have been published (see Patent Document 4). In this patent publication, a papermaking method using short fibers made of a direct spinning method is the best embodiment, but this is an entangled body of short fibers, which has surface strength such as wear resistance that can withstand long-term use. It is difficult to secure. In addition, it is difficult to produce ultrafine fibers of 0.1 dtex or less by the direct spinning method, and at a fineness of 0.1 dtex or more, the obtained leather-like sheet is inevitably textile-like, and the desired leather-like texture and appearance are obtained. It is difficult to obtain.
As described above, a flame-retardant leather-like sheet base that has a good texture that is soft and high-quality, has excellent surface strength such as abrasion resistance and peel strength, and has excellent shape stability. The material was not obtained.

JP-A-63-85185 JP 2002-115183 A JP 2004-19010 A JP 2004-169197 A

  The object of the present invention is a leather having a soft and high-quality feeling, excellent surface strength such as abrasion resistance and peel strength, excellent shape stability, and halogen-free flame retardancy. Another object is to provide a leather-like sheet base material that can be suitably used as an upholstery material for interior products such as vehicle seats, cushion sheets, sofas, and chairs.

Leather with halogen-free flame retardancy, sufficient surface strength, and excellent form stability that is suitable for use as an upholstery for interior products such as vehicle seats, cushion seats, sofas, and chairs As a result of diligent studies in obtaining the like sheet, the present invention has been achieved.
That is, the present invention is a non-woven fabric mainly composed of ultrafine fiber-generating fibers (a ′) capable of generating a fiber bundle composed of polyester ultrafine fibers (a) having a single fiber fineness of 0.5 dtex or less and containing no flame retardancy imparting component. (A) A flame-retardant polyester ultrafine fiber (b) having a single fiber fineness of 0.5 dtex or less, comprising a copolyester obtained by copolymerizing a phosphorus-containing compound so that a phosphorus atom concentration is 6,000 to 50,000 ppm. From a non-woven fabric (B) mainly composed of ultrafine fiber-generating fibers (b ′) capable of generating fiber bundles and a copolyester obtained by copolymerizing a phosphorus-containing compound so that the phosphorus atom concentration is 6,000 to 50,000 ppm A woven or knitted fabric (C) mainly composed of a flame retardant polyester fiber (c) or a fine fiber generating fiber (c ′) capable of generating the flame retardant polyester fiber (c). The fibers constituting the nonwoven fabric (A) and the fibers constituting the nonwoven fabric (B) are invaded through the woven or knitted fabric (C) by being laminated in the order of (A)-(C)-(B). A non-woven fabric that is combined and integrated by combining, and the ultrafine fiber generating fiber (b ′) constituting the non-woven fabric (B) is substantially in contact with the woven or knitted fabric (C) of the non-woven fabric (A); Does not reach the surface on the opposite side, but the ultrafine fiber-generating fiber (a ′) constituting the nonwoven fabric (A) reaches the surface on the opposite side to the surface in contact with the woven or knitted fabric (C) of the nonwoven fabric (B). It is the nonwoven fabric for flame-retardant leather-like sheet base material characterized by having reached. And it is preferable that the phosphorus atom density | concentration with respect to the total mass of a polyester microfiber (a), a flame-retardant polyester microfiber (b), and a flame-retardant polyester fiber (c) is 3,000 ppm or more.

Moreover, this invention consists of the above-mentioned nonwoven fabric for flame-retardant leather-like sheet base materials, and is comprised from a polyester extra fine fiber (a), a flame-retardant polyester extra fine fiber (b), and a flame-retardant polyester fiber (c). It is a flame retardant leather-like sheet base material in which the elastic polymer (D) is filled in a proportion of 5 to 50% with respect to the total fiber mass inside the formed nonwoven fabric.
And it is preferable that the metal hydroxide is contained in a proportion of 10 to 200% with respect to the mass of the elastic polymer (D).

  The non-woven fabric for flame-retardant leather-like sheet base material of the present invention, the flame-retardant leather-like sheet base material, and the leather-like sheet obtained therefrom are extremely excellent in flame retardancy, and are soft and high-quality. In addition, it has excellent wear resistance and peel strength, and has excellent shape stability.

The present invention is described in detail below.
The term “flame retardancy-imparting component” as used herein refers to a flame retardant (flame retardancy imparting additive) and ultrafine fiber added to the polyester ultrafine fiber in order to impart flame retardancy to the polyester ultrafine fiber. It means at least one kind of a flame retardancy-imparting copolymer component that is copolymerized in the polyester to impart flame retardancy to the polyester to be formed. Accordingly, the “polyester ultrafine fiber (a) not containing flame retardant imparting component” constituting the nonwoven fabric (A) includes both the flame retardant imparting additive and the copolymer component for imparting flame retardancy. Means extra fine fibers made of no polyester.

  Addition of flame retardants to polyester or copolymerization of flame retardant copolymer components improves flame retardancy, while fibers made from such polyesters have mechanical strength such as tensile strength and elongation. Tends to decrease. In the nonwoven fabric for flame-retardant leather-like sheet base material of the present invention, the nonwoven fabric constituting the surface layer is a polyester ultrafine fiber (a) that does not contain a flame-retardant imparting component (hereinafter referred to as “non-flame-retardant polyester ultrafine fiber (a)”). A polyester microfiber containing a flame retardancy imparting component by substantially not including any of the flame retardant imparting additive and the flame retardant imparting copolymer component. In comparison, it is excellent in mechanical strength such as tensile strength, abrasion resistance, and elongation, thereby bringing mechanical properties such as improved surface strength to the flame-retardant leather-like sheet substrate of the present invention. In the flame-retardant leather-like sheet base material of the present invention, the non-flame retardant constituting the nonwoven fabric (A) is provided in order to further improve the mechanical properties such as surface strength and to impart high wear resistance and peel strength. The tensile strength of the polyester microfiber (a) is preferably 1.6 g / dtex or more, more preferably 2.0 g / dtex or more. Such non-flame retardant polyester microfiber (a) is made of polyethylene. It is preferably formed from a polyester comprising one or more polyesters such as terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, etc. and containing no flame retardant additive (flame retardant) or copolymer component. Can do. In particular, the non-flame retardant polyester ultrafine fiber (a) is particularly preferably formed from polyethylene terephthalate which does not substantially contain a flame retardant for imparting flame retardancy or a copolymer component.

  The flame-retardant polyester extra fine fiber (b) and the flame-retardant polyester fiber (c) of the present invention are environmental pollution caused by halogen, various processes for producing a flame-retardant leather-like sheet base material and a leather-like sheet at the time of spinning. In this case, since the flame retardancy-imparting component does not fall off, it is formed from a copolymer polyester having a copolymer unit derived from a phosphorus-containing compound in the molecule as the flame retardancy imparting component.

  The copolymer units derived from the above phosphorus-containing compounds can be structural units derived from various phosphorus-containing compounds, such as oxaphospholane, phosphinic acid derivatives, phosphaphenanthrene derivatives, phosphoric triesters, Among them, a structural unit derived from a phosphorus-containing compound in which the phosphorus component is contained in the side chain is preferable from the viewpoints of good handleability during polymerization and prevention of strength reduction due to hydrolysis. Preferable examples include structural units having a skeleton derived from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide.

  As the polyester as the base of the copolymer polyester having a structural unit derived from a phosphorus-containing compound, known polyesters such as polyethylene terephthalate and polybutylene terephthalate, modified polymers thereof, mixed polymers, and copolymer polymers may be used. it can.

The production method of the copolyester having a structural unit derived from a phosphorus-containing compound is not particularly limited. For example, when a base polyester described above is produced by transesterification, it is produced by adding a phosphorus-containing compound during the transesterification reaction. can do. Moreover, when manufacturing the above-mentioned base polyester by direct esterification reaction, it can manufacture by adding a phosphorus containing compound before the polycondensation reaction or the initial stage of reaction.

  The flame-retardant polyester ultrafine fiber (b) and the flame-retardant polyester fiber (c) made of a copolyester obtained by copolymerizing a phosphorus-containing compound have a phosphorus atom concentration in the fiber of 6,000 to 50,000 ppm. It is important and is preferably 9,000 to 20,000 ppm. When the phosphorus atom concentration is less than 6,000 ppm, the flame retardancy of the flame-retardant leather-like sheet base material tends to be insufficient, whereas when it exceeds 50,000 ppm, embrittlement of the polyester constituting the ultrafine fiber or woven / knitted fabric is achieved. Further, the melt spinnability is lowered and the strength and elongation are easily lowered.

  Moreover, it is preferable that the phosphorus atom concentration with respect to the total mass of said non-flame retardant polyester microfiber (a), flame retardant polyester microfiber (b), and polyester fiber (c) is 3,000 ppm or more, and 4,500 ppm. More preferably. The upper limit varies depending on the thickness and is not particularly limited, but is preferably 40000 ppm or less. When the phosphorus atom concentration is less than 3,000 ppm, the non-flammable polyester microfiber (a) from the non-flammable leather-like sheet base non-woven fabric comprising the non-woven fabric (A), non-woven fabric (B) and woven / knitted fabric (C), Even if an elastic polymer (D) containing a flame retardant imparting component is contained inside the nonwoven fabric in which the flame retardant polyester extra fine fiber (b) and the flame retardant polyester fiber (c) are generated, It is difficult to obtain the level of flame retardancy that is required for the purpose of the present invention.

  In the flame-retardant leather-like sheet base material of the present invention, it is necessary that the single fiber fineness of the non-flame-retardant polyester ultrafine fiber (a) mainly forming the nonwoven fabric (A) is 0.5 dtex or less. It is preferably 0.0001 to 0.3 dtex, and more preferably 0.001 to 0.2 dtex. When the single fiber fineness of the non-flame retardant polyester ultra-fine fiber (a) exceeds 0.5 dtex, the texture of the flame retardant leather-like sheet base material becomes poor and the sense of fulfillment is lost. When a suede-like leather-like sheet is produced by raising a nonwoven fabric (A) made of non-flammable polyester ultrafine fibers (a) from a sheet base material as a surface, the fluff feeling and the lighting effect tend to be inferior. On the other hand, if the single fiber fineness is less than 0.0001 dtex, the dyeing property is lowered and color tone is liable to occur.

The flame retardant polyester extra fine fiber (b) mainly forming the nonwoven fabric (B) is not only in terms of the texture of the flame retardant leather-like sheet base material and the leather-like sheet comprising the flame retardant leather-like sheet base material, but also from the point of flame retardancy However, the single fiber fineness is required to be 0.5 dtex or less, preferably 0.0001 to 0.3 dtex, and more preferably 0.001 to 0.2 dtex. When the single fiber fineness of the flame-retardant polyester extra fine fiber (b) exceeds 0.5 dtex, the flame-retardant leather-like sheet base material becomes unsatisfactory and not only the feeling of fulfillment is lost, but also the desired flame retardancy. In order to impart the properties, the phosphorus atom concentration in the leather-like sheet substrate tends to be remarkably increased. On the other hand, if the single fiber fineness of the flame retardant polyester ultrafine fiber (b) is less than 0.0001 dtex, the melt spinnability will be extremely lowered, and the physical properties such as strength and elongation of the obtained fiber will also be reduced. Tend to.

  In the flame-retardant leather-like sheet base material of the present invention, the non-flame-retardant polyester ultrafine fiber (a) forming the nonwoven fabric (A) and the flame-retardant polyester ultrafine fiber (b) forming the nonwoven fabric (B) If necessary, one or more of carbon black, colorants such as dyes and pigments, various stabilizers such as light stabilizers, matting agents, antibacterial agents, antistatic agents, etc. Needless to say, it may be contained if necessary as long as other physical properties and appearance are not adversely affected. For example, when carbon black is contained and deposited in black, the addition amount of carbon black is preferably about 0.5 to 8% by mass from the viewpoint of spinnability and flame retardancy. Since carbon black is easily flammable, for example, when carbon black is contained at a ratio of 1 part by mass with respect to 100 parts by mass in total of non-flame retardant polyester extra fine fiber (a) and flame retardant polyester extra fine fiber (b) Preferably has a phosphorus atom concentration in the flame-retardant polyester microfiber (b) of 6,000 ppm or more. When carbon black is contained in a proportion of 2 parts by mass, for example, the flame-retardant polyester microfiber (b) ) Is preferably set to 8,000 ppm or more.

The flame retardant leather-like sheet base material of the present invention is a non-flame retardant polyester extra fine fiber (a) in the flame retardant leather like sheet base material: a flame retardant polyester extra fine fiber (b) and a flame retardant polyester fiber (c). Is preferably 10:90 to 90:10, more preferably 15:85 to 85:15, and still more preferably 20:80 to 80:20.
When the lamination mass ratio of the non-flame retardant polyester ultrafine fiber (a) is less than 10% by mass, the high-stretch property of the flame-retardant leather-like sheet base material is lowered, and the surface strength such as surface wear resistance is also lowered. To do. On the other hand, when the lamination | stacking mass ratio of a non-flame retardant polyester extra fine fiber (a) exceeds 90 mass%, the flame retardance of a flame-retardant leather-like sheet base material will fall.

  The woven or knitted fabric (C) used in the present invention comprises a flame retardant polyester fiber (c) or a fine fiber generating fiber (c ′) copolymerized with a phosphorus-containing compound. Either woven fabric or knitted fabric mainly composed of A woven fabric is preferable in that it can provide high form stability that is suitably used for an interior product such as a vehicle seat, a cushion seat, a sofa, or a chair. In the case of a woven fabric, the number of twists in the range of about 300 to 1200 T / m is preferable, and the total fineness of the yarn can be selected in the range of 50 to 200 dtex depending on the desired strength and texture. . If the number of twists is about 300 T / m or more, it is preferable because the woven fabric has a stable form in terms of material design restrictions in the intended use of the present invention, and the number of twists is 1200 T / m or less. From the viewpoint of the balance of texture with the nonwoven fabric (A) and the nonwoven fabric (B) and the sense of unity. If the fineness is about 50 dtex or more, the material design in the intended use of the present invention is preferable because a stable performance can be obtained in the form retention that is the role of the fabric, and the fineness is about 200 dtex or less. If it is, it is difficult to adversely affect the surface smoothness of the nonwoven fabric (A) and the nonwoven fabric (B) disposed via the woven or knitted fabric (C), and the balance of the texture with the nonwoven fabric (A) and the nonwoven fabric (B) It is also preferable in terms of unity.

The elastic polymer (D) used in the present invention may be any elastic polymer that has recoverability and has properties such as durability and abrasion resistance. For example, polyurethane elastomer, polyester-based thermoplastic elastomer , Polyamide-based thermoplastic elastomers, elastic hydrogenated styrene-isoprene block copolymers, acrylic rubber, natural rubber, SBR, NBR, polychloroprene, polyisoprene, isobutylene isoprene rubber, and the like. The coalescence may be used alone or in combination of two or more.
Among them, the elastic polymer (D) is excellent in flexibility and elastic recovery, excellent in durability such as abrasion resistance, excellent in mechanical properties such as tensile strength and dyeing properties, and porous. A polyurethane elastomer is preferably used because it is easy to form a structure.

As the polyurethane elastomer, any polyurethane resin having elasticity can be used. In particular, a high molecular diol having a number average molecular weight of 500 to 5000 is used as a soft segment component, an organic diisocyanate is used as a hard segment component, and a low molecular weight together with these components. A polyurethane obtained by reacting a chain extender is preferably used.
If the number average molecular weight of the polymer diol used for the production of polyurethane is less than 500, the soft segment is too short, and the polyurethane lacks flexibility, making it difficult to obtain a flexible leather-like sheet substrate. is there. On the other hand, when the number average molecular weight of the polymer diol exceeds 5,000, the proportion of urethane bonds in the polyurethane is relatively reduced, resulting in a decrease in durability, heat resistance, hydrolysis resistance, and the like. It becomes difficult to obtain a flame-retardant leather-like sheet base material and a leather-like sheet having

  Examples of the polymer diol used in the production of polyurethane include polyester diol, polylactone diol, polycarbonate diol, polyester polycarbonate diol, polyether diol and the like obtained by reaction of a dicarboxylic acid component and a diol component. One or more of these polymer diols can be used.

  As the organic diisocyanate used in the production of polyurethane, any of the organic diisocyanates conventionally used in the production of polyurethane can be used. For example, 4,4′-diphenylmethane diisocyanate, tolylene diisocyanate, phenylene diisocyanate, xylylene Aromatic diisocyanates such as diisocyanate, isophorone diisocyanate, 1,5-naphthylene diisocyanate; aliphatic diisocyanates such as hexamethylene diisocyanate; alicyclic diisocyanates such as 4,4′-dicyclohexylmethane diisocyanate, hydrogenated xylylene diisocyanate, etc. Can be mentioned. One or more of the above-mentioned organic diisocyanates can be used.

  As the low molecular chain extender used in the production of polyurethane, any of low molecular chain extenders conventionally used in the production of polyurethane, particularly low molecular chain extenders having a molecular weight of 400 or less, can be used. For example, ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, N-methyldiethanolamine, 1,4-cyclohexanediol, bis Diols such as-(β-hydroxyethyl) terephthalate, xylylene glycol, 1,4-bis (β-hydroxyethoxy) benzene; hydrazine, ethylenediamine, propylenediamine, isophoronediamine, piperazine and derivatives thereof, phenylenediamine, tolylenediamine Diamines such as ethylene, xylylenediamine, adipic acid dihydrazide, isophthalic acid dihydrazide, hexamethylenediamine, 4,4'-diaminophenylmethane, 4,4'-dicyclohexylmethanediamine; amino such as aminoethyl alcohol and aminopropyl alcohol Alcohols etc. can be mentioned, These 1 type (s) or 2 or more types can be used.

In the production of polyurethane, the above-mentioned equivalent ratio of [total isocyanate groups] / [total functional groups that react with isocyanate groups such as hydroxyl groups and amino groups] is in the range of 0.9 to 1.1. It is preferable to react a polymer diol, an organic diisocyanate and a low molecular chain extender from the viewpoint of obtaining a flame-retardant leather-like sheet substrate and a leather-like sheet having high tear strength.
In addition, for the purpose of improving the solvent resistance, heat resistance, hot water resistance, etc. of polyurethane, it is crosslinked in the polyurethane by reacting with trifunctional or higher polyols such as trimethylolpropane or trifunctional amines as necessary. You may give a structure.

  As the flame retardancy imparting component to be contained in the elastic polymer (D) of the present invention, known flame retardants can be used, but non-flame retardant polyester extra fine fibers (a), flame retardant polyester extra fine fibers (b ) And a flame retardant polyester fiber (c), and a solidification bath for coagulating the elastic polymer (D) impregnated in the nonwoven fabric, and a treatment for making the ultrafine fiber generating fiber into ultrafine fibers It is preferable to use a metal hydroxide in that it is not dissolved in the liquid, decomposed or altered by them. Among these, aluminum hydroxide is more preferably used. The particle size of aluminum hydroxide is not particularly limited, but the average particle size is preferably 2 μm or less, preferably 1 μm or less from the viewpoint of achieving both dispersion stability in the impregnating solution and flame retardancy. Is more preferable. The aluminum hydroxide may be subjected to various treatments for improving performance such as moisture resistance, heat resistance, water resistance, acid resistance and the like as necessary.

  The content of the metal hydroxide in the elastic polymer (D) is preferably in the range of 10 to 200%, more preferably 30 to 100% with respect to the mass of the elastic polymer (D). preferable. If the content of the metal hydroxide is less than 10%, it becomes difficult to impart sufficient flame retardancy to the flame-retardant leather-like sheet substrate, while if it exceeds 200%, an elastic polymer (D ) It becomes difficult to contain a metal hydroxide in a stable state, the embrittlement of the elastic polymer (D) containing the metal hydroxide (D) is likely to occur, and the physical properties are lowered. The texture of the sheet base material tends to become hard.

In the flame-retardant leather-like sheet base material of the present invention, as described above, the flame-retardant polyester ultrafine fiber (b) and the flame-retardant polyester fiber (c) constituting the nonwoven fabric (B) are phosphorous-free without halogen atoms. Environmental problems associated with the use of halogenated compounds by using aluminum hydroxide as a flame retardant component that is formed from a phosphorus-containing copolymer polyester having atoms in the molecule and further contained in the elastic polymer (D) It is preferable in that a sufficient level of flame retardancy can be achieved without occurrence.
Although it is difficult to theoretically prove the detailed reason, the combustion suppression mechanism and water by the carbonization film formation by the phosphorus component contained in the phosphorus-containing copolymer polyester which forms a flame-retardant polyester extra fine fiber (b) and water It is presumed that the combustion suppression machine due to the endothermic heat of aluminum oxide exhibits a synergistic effect by suppressing combustion at a plurality of locations in the combustion process.

  The elastic polymer (D) may contain carbon black as required for the purpose of improving the dark color of the flame retardant leather-like sheet base material, and is processed into a high density color such as black. Preferably contains carbon black. When carbon black is contained in the elastic polymer (D), the amount is preferably 7 parts by mass or less, more preferably 5 parts by mass or less with respect to 100 parts by mass of the elastic polymer (D). . In this case, the content of aluminum hydroxide is preferably adjusted to be a large amount within the range of 100 to 200 parts by mass. For example, when 3 parts by mass of carbon black is contained with respect to 100 parts by mass of the elastic polymer (D), the content of aluminum hydroxide is preferably 25 parts by mass or more, and 40 parts by mass or more. Is more preferable.

  In the flame-retardant leather-like sheet base material of the present invention, [non-flame-resistant polyester ultrafine fiber (a), difficult to obtain, from the viewpoint of obtaining a natural leather-like soft texture, wear resistance, and flame resistance. The mass ratio of the total mass of the flammable polyester microfiber (b) and the flame retardant polyester fiber (c)]: [the mass of the elastic polymer (D) (not including the flame retardant component)] is 95: 5. -50: 50 is preferable, and 85: 15-60: 40 is more preferable. Non-flame retardant polyester ultrafine fiber (a), flame retardant polyester ultrafine fiber (b), and non-flame retardant polyester ultrafine fiber relative to the total mass of flame retardant polyester fiber (c) and the mass of elastic polymer (D) When the ratio of the total mass of (a), the flame-retardant polyester extra-fine fiber (b) and the flame-retardant polyester fiber (c) is less than 50% by mass, a rubber-like texture tends to be obtained, and the flame retardancy is unstable. It is easy to become. On the other hand, when it exceeds 95% by mass, it becomes easy to cause dropping of ultrafine fibers, a decrease in pilling resistance, and the like.

The thickness of the flame retardant leather-like sheet base material can be arbitrarily selected according to the use, etc., but generally, about 0.5 to 2.0 mm in terms of texture, strength, ease of handling, etc. It is preferable that the thickness is about 0.6 to 1.5 mm. Also, the basis weight of the flame-retardant leather-like sheet substrate is soft texture, in order to obtain an appropriate elasticity feeling and resilience is preferably ^{250~1,000g / m 2, 300~600g / m} 2 It is more preferable that Furthermore, in the flame-retardant leather-like sheet base material, the ratio of the thickness of the nonwoven fabric (A) to the nonwoven fabric (B) is 50:50 to 20:80, such as flame retardancy, strength, and abrasion resistance. From the point of view, it is preferable.

  In the flame-retardant leather-like sheet base material of the present invention, at least the flame-retardant polyester extra-fine fiber (b) is present as a fiber bundle, so that it is slightly more flame-retardant than the ultra-fine fiber having the same fineness is present alone. Compared with the case where the total fineness of the ultrafine fiber bundle is equal, the fiber bundle in which many finer fibers with smaller fineness are converged tends to have a slightly improved flame retardancy. Therefore, the flame retardant improvement mechanism does not go out of speculation, but if you use a flame retardant polyester with the same phosphorus content per unit mass, in the flame retardant leather-like sheet base material Forming a layer in which the amount of flame retardant polyester is concentrated when viewed per unit volume is more effective from the viewpoint of flame retardancy, and the surface of the flame retardant polyester when viewed per unit volume To such Gayori increase is more effective in terms of flame retardancy. Further, non-flame retardant polyester ultrafine fiber (a), flame retardant polyester ultrafine fiber (b) or flame retardant polyester fiber (c) constituting the composite nonwoven fabric, and elastic polymer (D) contained therein Are not substantially adhered to each other, and the fiber and the elastic polymer (D) are preferably separated. Since the fiber and the elastic polymer (D) are not bonded, the fiber is not restrained by the elastic polymer, and the degree of freedom of movement is increased, and a soft texture like natural leather can be imparted. Such a state is obtained by the method described below.

  The method for producing the flame-retardant leather-like sheet substrate of the present invention is not particularly limited, and may be produced by any method capable of producing the flame-retardant leather-like sheet substrate of the present invention having the structure and characteristics described above. However, as the polyester ultrafine fiber constituting the flame retardant leather-like sheet base material, it is necessary to use an ultrafine fiber-generating fiber in order to give the obtained leather-like sheet a soft texture like natural leather. It can be manufactured smoothly by the manufacturing method.

(I) A web or non-woven fabric made of an ultrafine fiber-generating fiber (a ′) capable of forming a polyester ultrafine fiber having a single fiber fineness of 0.5 dtex or less that does not contain a flame retardancy imparting component, and a single fiber fineness of 0.5 dtex or less A non-woven fabric for a flame-retardant leather-like sheet base material is formed by laminating a web or a non-woven fabric and a woven or knitted fabric (C) made of an ultra-fine fiber-generating fiber (b ') capable of forming a flame-retardant polyester extra-fine fiber To manufacture.
(II) After providing the elastic polymer (D) to the non-woven fabric for flame-retardant leather-like sheet base material obtained in the step (I), the ultra-fine fiber generating fiber (a ′) and ultra-fine fiber constituting the non-woven fabric The generation type fiber (b ′) is made into ultrafine fibers, and each is converted into a non-flame retardant polyester ultrafine fiber (a) having a single fiber fineness of 0.5 dtex or less and a flame retardant polyester ultrafine fiber (b) having a single fiber fineness of 0.5 dtex or less When the knitted or knitted fabric (C) is composed of fine fiber-generating fibers (c ′) that generate the flame-retardant polyester fibers (c), the flame-retardant polyester fibers (c) Or the non-flame-retardant polyester ultrafine fiber (1) is formed from the non-flammable polyester ultrafine fiber (1). a), flame retardant polyester After transformation into ultrafine fibers (b) and flame retardant polyester fibers (c), a flame retardant leather-like sheet substrate is produced by applying an elastic polymer (D).

  In the above production method, as the ultrafine fiber generating fiber (a ′) forming the web or the nonwoven fabric, a polyester that does not contain a flame retardancy-imparting component is used as an island component, and the polyester is different in solubility or decomposability from the polyester. Layered, concentric circles of mixed-spun fibers or composite-spun fibers with a sea-island cross-section with a polymer as the sea component, polyesters that do not contain flame retardant components, and other polymers that differ in solubility or degradability from the polyester For example, a composite spun fiber having a cross-sectional shape of a multi-layer bonded type in the form of a shape (core-sheath) or a petal is preferably used.

  Further, in the above production method, as the ultrafine fiber generating fiber (b ′) forming the web or the nonwoven fabric, in the specific example of the ultrafine fiber generating fiber (a ′), a polyester containing no flame retardant component A mixed spun fiber, a composite spun fiber, or the like obtained by substituting with a copolyester obtained by copolymerizing a phosphorus-containing compound is preferably used.

  The above-mentioned sea-island-type and multilayer-laminated mixed-spun fibers and composite-spun fibers can be produced by a conventionally known melt-mixed spinning method, melt-combined spinning method, or the like.

  The ultrafine fiber generating fiber (a ′) or the ultrafine fiber generating fiber (b ′) is a polyester that does not contain a flame retardancy imparting component or a polyester that contains a flame retardancy imparting component and the polyester has solubility or decomposability. Used in combination with different polymers. Examples of polymers having different solubility or degradability from the polyester include, for example, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polystyrene, styrene-ethylene copolymer, modified polyvinyl alcohol, or Examples thereof include modified polyesters such as sulfoisophthalic acid-modified polyethylene terephthalate. Unlike polyesters containing no flame retardancy imparting component or polyesters containing flame retardancy imparting component, these polymers are easily dissolved in solvents such as toluene, trichrene, water, etc. By treating a web or non-woven fabric made of ultrafine fiber generating fiber (a ′) or ultrafine fiber generating fiber (b ′) with a solvent or a decomposing agent before or after impregnation of the elastic polymer (D), It becomes a flame-retardant polyester microfiber (a) or a flame-retardant polyester microfiber (b). At that time, the non-flame retardant polyester extra fine fiber (a) or the flame retardant polyester extra fine fiber (b) is ultra fine in the layer (A) and the layer (B) constituting the flame retardant leather-like sheet base material, respectively. A non-woven fabric is formed by forming a fiber bundle and intertwining each other.

  As the fiber constituting the woven or knitted fabric (C), the flame retardant polyester and the flame retardant polyester are composed of polymers having different solubility or decomposability as in the case of the ultrafine fiber generating fiber (b ′), and are flame retardant. Fine fiber generating fibers (c ′) that can generate polyester fibers (c) can also be used. The fine fiber generating fiber (c ′) may be produced from the spinning stage using a mixed spinning method or a composite spinning method, but a woven or knitted fabric is produced. The flame retardant polyester fiber (c) is coated with a polymer having a different solubility or decomposability from the flame retardant polyester at the stage of the yarn immediately before the woven or knitted fabric is formed. The fiber (c) may be coated with a polymer having a different solubility or degradability from the flame retardant polyester. In the case of such a coating method, the fiber (c) is soluble in the flame retardant polyester. Alternatively, polymers having different degradability include, for example, water-soluble polymers such as polyvinyl alcohol.

More specifically, the above production method can be performed as follows.
1a: A sea-island type of polyester that does not contain a flame retardancy-imparting component and is a sea component of a polymer that is different in solubility or decomposability from the flame-retardant polyester by a melt mixing spinning method, a melt composite spinning method, or the like. Perform mixed spinning or composite spinning, or perform multi-layer bonded mixed spinning or composite spinning consisting of a polyester that does not contain a flame retardancy-imparting component and a polymer having different solubility or decomposability. A sea-island type or multilayer bonded type ultrafine fiber generating type fiber (a ') is produced. Thereafter, a staple is manufactured through a drawing, crimping, and cutting process.
The staple preferably has a single fiber fineness of about 1.0 to 10.0 dtex, particularly about 3.0 to 6.0 dtex from the viewpoint of good card passing properties. Next, the staple is defibrated with a card, a web is formed through the webber, the web is overlapped with a desired weight and thickness, and then entangled by performing needle punching using a needle with a barb, Let it be the nonwoven fabric (A) which consists of an extra fine fiber generation type | mold fiber (a '). Here, the nonwoven fabric (A) and the nonwoven fabric (B) are invaded and intertwined with each other via the woven or knitted fabric (C) which is an important state in the nonwoven fabric for flame-retardant leather-like sheet base material of the present invention. However, the ultrafine fiber generation type fiber (b ′) of the nonwoven fabric (B) does not substantially reach the surface of the nonwoven fabric (A) via the woven or knitted fabric (C), and the ultrafine fiber generation type of the nonwoven fabric (A). In order to realize a state in which the fiber (a ′) reaches the surface of the nonwoven fabric (B) via the woven / knitted fabric (C), the nonwoven fabric (A) is laminated with the nonwoven fabric (B) via the woven / knitted fabric (C). Then, before performing the entanglement process, it is preferable to perform needle punching for the purpose of preliminary entanglement so as to obtain a desired entanglement state. As a guide, needle punching is performed in a range of about 100 to 1,000 punches / cm ^{2 in} terms of the number of needle punches, whereby the nonwoven fabric (A) is densified in advance than the nonwoven fabric (B). By doing so, when the non-woven fabric (B) side fibers enter the non-woven fabric (A) via the woven or knitted fabric (C), it is suppressed from penetrating to the surface on the opposite side at once, and deeper than necessary. Without being entangled with the fibers on the nonwoven fabric (A) side. Such an entangled integrated state is difficult to realize by an entanglement method using a high-pressure water flow, and therefore, an entanglement means using a high-pressure water flow may be used in combination, but the main entanglement process is preferably performed by needle punching. . In addition to the appearance, texture, mechanical properties, etc., as long as it does not impair the flame retardance, which is the biggest problem to be solved by the present invention, it depends on the quality of the fibers to be mixed. As long as the ratio is 15% or less, fibers other than the ultrafine fiber generating fiber (a ′) may be mixed.
1b: A staple of ultrafine fiber-generating fiber (b ′) produced by the same operation as in 1a above using a copolymerized polyester obtained by copolymerizing a phosphorus-containing compound instead of a polyester containing no flame retardancy-imparting component Is defibrated with a card, a web is formed through a webber, the web is overlapped to a desired weight and thickness, and then entangled by needle punching using a needle with a barb, thereby generating ultrafine fibers. A web or non-woven fabric (B) made of mold fibers (b ′) is produced. Here, the non-woven fabric (B) is laminated with the non-woven fabric (A) through the woven or knitted fabric (C) in order to realize the above-mentioned entangled state important in the non-woven fabric for flame-retardant leather-like sheet base material of the present invention. As a guideline, the needle punching performed before the entanglement treatment is preferably in the range of 100 punch / cm ² or less in terms of the number of needle punches, that is, in a pre-entangled state where the density is lower than that of the nonwoven fabric (A).
Thus, densifying a nonwoven fabric (A) with respect to a nonwoven fabric (B) as a state before needle punching for the composite integration of a nonwoven fabric (A), a nonwoven fabric (B), and a woven / knitted fabric (C) Thus, in needle punching from the nonwoven fabric (A) side, the fibers of the nonwoven fabric (A) easily penetrate deeply into the nonwoven fabric (B) side through the woven or knitted fabric (C), so that the woven or knitted fabric (C ) And non-woven fabric (B) fibers are strongly entangled, but in needle punching from the non-woven fabric (B) side, the non-woven fabric (B) fibers are woven and knitted (C) through the non-woven fabric (A) side thickness. It is difficult to penetrate deeply in the direction, and the fibers of the nonwoven fabric (B) are shallow in the thickness direction of the fibers of the woven / knitted fabric (C) and the nonwoven fabric (A), and in the vicinity of the surface in contact with the woven / knitted fabric (C) and the woven / knitted fabric (C) By strongly entangled only with the fibers constituting the nonwoven fabric (A) , It is possible to composite integrated by intertwining state of sufficient strength of fiber entering to each other via a woven or knitted fabric of (C).
1c: a flame retardant polyester fiber (c) made of polyester copolymerized with a phosphorus-containing compound obtained by a melt direct spinning method or the like, preferably a predetermined number of fibers in the range of 20 to 200 is converged, and the total fineness of the yarn is Preferably in the range of 50 to 200 dtex, twisted as necessary, or a polyester copolymerized with a phosphorus-containing compound and a polymer having a different solubility or decomposability from the polyester, a mixed spinning method, a composite spinning method, etc. The flame retardant polyester fiber (c) is coated with a fine fiber generating fiber (c ′) such as a mixed spun fiber or a composite spun fiber obtained by the above, or a polymer having solubility or decomposability different from that of the polyester. Preferably, 20 to 200 polyester fibers (c ′) and the like are converged to a predetermined number, Taru fineness preferably in the range of 50～200Dtex, after applying twists as required, to produce a knitted fabric (C) woven by a conventionally known method.

2: The non-woven fabric (A) obtained in 1a and 1b, the non-woven fabric (B), and the woven or knitted fabric (C) obtained in 1c are overlapped. As for the superposition method, the non-woven fabric (A) is the upper layer, and the woven or knitted fabric (C) is laminated in the middle layer, and the non-woven fabric (B) is laminated in three layers.

3: The web or the nonwoven fabric and the woven or knitted fabric obtained in 2 above are subjected to entanglement treatment by using a known method such as needle punching and, if necessary, high-pressure water entanglement. A non-woven fabric for a flame-retardant leather-like sheet base material integrated and integrated is manufactured. At that time, the flame-retardant ultrafine fiber generating fiber (b ′) of the back layer does not reach the surface opposite to the surface of the surface nonwoven fabric (A) that is in contact with the woven or knitted fabric (C), and the nonwoven fabric (A The non-flammable ultrafine fiber generating fiber (a ′) constituting the) is entangled so that it reaches the surface opposite to the surface of the non-woven fabric (B) in contact with the woven or knitted fabric (C). There is a need to do. This is because even if the flame retardant component concentration in the base material is the same, in the thickness direction, the flame retardant component is concentrated and localized in a layered state, and the flame retardancy is improved and less. This is because high flame retardancy can be exhibited even with a phosphorus content, so that the flame-retardant polyester ultrafine fibers (b) are concentrated rather than existing throughout the thickness direction of the nonwoven fabric. The needle punching from the nonwoven fabric (A) side is performed in a state where the barb of the needle penetrates the surface on the opposite side to the surface that contacts the woven or knitted fabric (C) of the nonwoven fabric (B) through the woven or knitted fabric (C). However, needle punching from the nonwoven fabric (B) side does not allow the needle barb to penetrate the surface of the nonwoven fabric (A) opposite to the surface that contacts the woven fabric (C) via the woven fabric (C). It is more preferable to perform the adjustment in order to obtain the above-described structure.
In particular, the woven or knitted fabric (C) has a surface in which the flame-retardant ultrafine fiber generating fiber (b ′) constituting the nonwoven fabric (B) is in contact with the woven or knitted fabric (C) of the nonwoven fabric (A) on the nonwoven fabric (A) side. Entanglement of the non-flame retardant ultrafine fiber generating fiber (a ′) and the fibers constituting the woven or knitted fabric (C) and the flame retardant ultrafine fiber generating fiber (b ′) while suppressing the penetration to the opposite surface ) And the fibers constituting the woven or knitted fabric (C) are effective in improving the physical properties of the non-woven fabric for flame-retardant leather-like sheet base material and flame-retardant leather-like sheet base material obtained by sufficiently intertwining each other. Essential in terms. By concentrating the flame-retardant polyester extra fine fibers (b) in this way, not only can the desired flame retardancy be realized with a lower phosphorus content, but also when the flame-retardant leather-like sheet base material is dyed, Flame retardant polyester microfibers with different dyeing properties and inferior physical properties are not substantially mixed on the surface made of combusted polyester ultrafine fibers, so surface properties such as appearance quality and wear resistance are not impaired. At the same time, it has a secondary effect.

The non-woven fabric for flame-retardant leather-like sheet base material (hereinafter sometimes referred to as a laminate entangled product) composed of a non-woven fabric and a woven or knitted fabric obtained in this step has a basis weight of 200 to 1500 g / m ² and a thickness of 1. It is preferable that the thickness is about 10 mm from the viewpoint of handleability during the process.
Further, the laminated entangled product obtained in this step is further provided with a polyvinyl alcohol-based paste, or the entire laminated entangled product or the surface portion is heated to melt the surface of the constituent fiber to obtain the laminated entangled product. May be bonded or fused together to temporarily fix the fiber entangled structure in the nonwoven fabric. By performing such a treatment, it is possible to prevent structural breakage of the nonwoven fabric from being caused by tension or the like during the subsequent impregnation step of the elastic polymer. By adjusting the surface smoothness by melting the surface of the fibers that make up the laminated entangled product, the surface smoothness of the flame-retardant leather-like sheet base material that is finally obtained can be adjusted. You may implement according to it. Further, after applying a polyvinyl alcohol-based sizing agent to the laminated entangled product and impregnating the elastic polymer (D), the polyvinyl alcohol-based sizing agent is removed to obtain a more non-flammable polyester extra fine fiber (a ), A flame-retardant polyester extra fine fiber (b) and a flame-retardant polyester fiber (c) and the elastic polymer (D) can be spaced at a desired interval, and each fiber of the elastic polymer (D) Since restraint can be moderately suppressed, the rubber-like texture of the elastic polymer is moderately eased from appearing on the front surface, and a softer texture like natural leather can be imparted.

4: Next, after applying the elastic polymer (D) containing a flame retardant imparting component to the laminated entangled product obtained in 3 above as necessary, the ultrafine fiber generating fiber (a ') And the ultrafine fiber-generating fiber (b') are made into ultrafine fibers, and when the fiber constituting the woven or knitted fabric (C) is the fine fiber-generating fiber (c '), this is modified, or The ultrafine fiber generating fiber (a ′) and the ultrafine fiber generating fiber (b ′) constituting the laminated entangled product obtained in 3 were converted into ultrafine fibers, and the fibers constituting the woven or knitted fabric (C) were generated as fine fibers. In the case of the mold fiber (c ′), after modifying this, an elastic polymer (D) containing a flame retardancy-imparting component is imparted as necessary to obtain a flame retardant leather-like sheet base material.
In this step, the laminated entangled product is impregnated into the laminated entangled product by immersing the laminated entangled product in the solution or dispersion of the elastic polymer (D) before or after the modification of the fiber such as ultrafine fiber. And then immersing it in a coagulation bath to coagulate the elastic polymer (D) in a porous state, or coagulating the elastic polymer (D) by a method such as heat drying or heat-sensitive gelation. Preferably employed. When an insoluble material such as aluminum hydroxide is used as the flame retardant component to be contained in the elastic polymer (D) as necessary, the insoluble flame retardant in the liquid containing the elastic polymer (D) is used. It is necessary to disperse the imparting component in advance, and additives such as a coagulation regulator and a dispersant may be blended as necessary for the purpose of improving dispersion stability. Moreover, you may add the deterioration preventing agent, coloring agent, etc. of an elastic polymer (D) in the liquid containing an elastic polymer (D) in the range which does not impair the objective of this invention.

In addition, the ultrafine fiber generating fiber (a ′) and the ultrafine fiber generating fiber (b ′) in this step are converted into the ultrafine fiber generating fiber (a ′) and the ultrafine fiber generating fiber (b ′). The constituent polyester does not dissolve or decompose, but is used with a solvent that dissolves other polymers or a chemical that decomposes. In that case, when the elastic polymer (D) is previously contained in the laminated entangled product, it is necessary to use a solvent that does not dissolve the elastic polymer (D) or a chemical that does not decompose. When the flame retardancy-imparting component contained in the elastic polymer (D) is aluminum hydroxide, aluminum hydroxide is not dissolved or decomposed by a solvent that dissolves other polymers or a decomposing agent. Most of the water is stably held in the elastic polymer (D) as it is.
In the flame-retardant leather-like sheet base material after ultrafine fiber obtained in this way, the content of the elastic polymer (D) is 10% by mass as a solid content with respect to the mass of the flame-retardant leather-like sheet base material. It is preferable that it is the above, and it is more preferable that it is 30-50 mass%. When the content of the elastic polymer (D) is less than 10% by mass, it becomes difficult to form a dense porous elastic polymer in the laminated entangled product, and the flame retardancy-imparting component of aluminum hydroxide is easily removed. In addition, the mechanical properties of the obtained flame-retardant leather-like sheet base material tend to deteriorate.

  The front and back sides of the flame-retardant leather-like sheet base material of the present invention are not particularly limited, but preferably the surface of the nonwoven fabric (A) side made of non-flame-retardant polyester ultrafine fibers (a) is used by a known method. A suede-like leather-like sheet excellent in appearance quality, surface touch and the like can be obtained by fluffing and coloring by a method such as dyeing if necessary. Further, the surface of the flame retardant leather-like sheet base material is preferably treated with a solvent or heat to dissolve or melt fibers or elastic polymers in the vicinity of the nonwoven fabric (A), or thin the elastic polymer. After application, the fluff is similarly shortened by a known method, or after the surface of the nonwoven fabric (A) side is fluffed, treated with a solvent or heat, or by applying an elastic polymer thinly. It is also possible to obtain a leather-like sheet having a so-called semi-silvered appearance, which is a nubuck-like appearance or an intermediate appearance with suede and silver.

Furthermore, the flame-retardant leather-like sheet substrate of the present invention is a nonwoven fabric (A) -side surface formed from a nonwoven fabric made of non-flame-retardant polyester ultrafine fibers (a), or flame-retardant polyester ultrafine fibers (b). By forming a resin film on the surface of the non-woven fabric (B) side (hereinafter sometimes referred to as “surface formation”), a silvered leather-like sheet can be obtained. The surface forming method is not particularly limited, and may be a known wet method, dry method, or a method of smoothing the surface with embossing or the like after the substrate surface is dissolved or melted with a solvent or heat or imparting unevenness to the surface. It can carry out by implementing combining suitably.
The resin used for the surface forming is preferably the same type of resin as the elastic polymer (D) constituting the flame-retardant leather-like sheet base material. For example, when the elastic polymer (D) is a polyurethane elastomer, polyurethane is preferably used as the surface-forming resin.
The thickness of the resin to be formed is not particularly limited, but is usually preferably about 10 to 300 μm. When the thickness of the surface-forming resin layer exceeds 50 μm, for example, 50 μm, it is preferable to add a flame retardant also to the surface-forming resin layer. As the flame retardant in that case, one or more of phosphorus-based organic or inorganic compounds, aluminum hydroxide or other metal hydroxides are preferably used. The amount of the flame retardant added to the surface-forming resin layer is not particularly limited, but is 100 parts by mass or less with respect to 100 parts by mass of the surface-forming resin from the viewpoint of process stability during surface formation, strength of the surface-forming film, and the like. It is preferable to use in proportion.

As described above, the suede-like leather-like sheet and the silver-finished leather-like sheet obtained from the flame-retardant leather-like sheet base material of the present invention are vehicle seats, particularly automobiles, that require high surface strength as well as flame resistance. It is suitably used as an upholstery material for interior products such as passenger seats, railcar seats, airplane seats, ship seats, cushions, seats, chairs and the like.
In addition, the use of the leather-like sheet is not limited to the above-described use, and can be widely used for clothing, shoes, bags, accessory cases, gloves, and other miscellaneous goods.
Example

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples. In the following examples, the single fiber fineness of the fiber, the average particle size of aluminum hydroxide, the leather-like sheet substrate and the flame retardancy of the dyed suede-like leather-like sheet obtained by buffing and dyeing it, the leather-like sheet base The phosphorus atom concentration in the material, the abrasion resistance of the leather-like sheet substrate, and the texture of the suede-like leather-like sheet obtained by buffing the surface of the leather-like sheet substrate were measured or evaluated as follows. .

(I) Single fiber fineness of the fiber:
Observed with an electron microscope at a magnification of about 500 to 2000 times, the fiber diameter was measured at about 30 to 100 locations, and the single fiber fineness (dtex) was obtained by calculation from the average value of the measured values and the density of the fiber component. It was.

(Ii) Average particle size of aluminum hydroxide:
The diameters of a large number (about 30 to 100) of aluminum hydroxide particles were measured by observing with an electron microscope, and the average value of the measured values was calculated.

(Iii) Flame retardancy of leather-like sheet substrate and dyed leather-like sheet:
In accordance with JIS D1201, "Combustion test method for organic materials for automobile interiors", a combustion test was performed on a leather-like sheet base material, and evaluation was performed based on the following criteria. The same applies to the dyed leather-like sheet obtained by dyeing the leather-like sheet base material after buffing according to the method described in the section (6) [Suede-like leather-like sheet texture] below. A flame test was conducted to evaluate flame retardancy.
[Evaluation criteria for flame retardancy]
・ Flammability: Burning speed exceeding 100 mm / min.
・ Slow flammability: Combustion rate of 100 mm / min or less.
-Self-extinguishing: Fire extinguished within 50 mm and within 60 seconds from the marked line.

(Iv) Phosphorus atom concentration in polyester and leather-like sheet substrate:
(Iv) -1: Phosphorus atom concentration in polyester:
After the material was decomposed and dissolved with a strong acid, the concentration of phosphorus atoms in the polyester was measured using an ICP emission analyzer manufactured by Jarrel Ash.
(Iv) -2: Phosphorus atom concentration in the leather-like sheet substrate:
By the measurement method of (iv) -1, the polyester that forms the non-flame retardant polyester ultrafine fiber (a), the polyester that forms the flame retardant polyester ultrafine fiber (b), and the flame retardant polyester fiber (c) are formed. The phosphorus atom concentration of each polyester is measured, and from the respective masses of the non-flame retardant polyester ultrafine fiber (a), the flame retardant polyester ultrafine fiber (b) and the flame retardant polyester fiber (c) in the leather-like sheet substrate, The phosphorus atom density | concentration with respect to the total mass of the fiber contained in a leather-like sheet base material was calculated | required.

(V) Abrasion resistance of leather-like sheet substrate:
In accordance with JIS L1096 “Abrasion Strength E Method (Martindale Method)”, a standard wear cloth was used, and the mass (mg) decreased when tested at a pressure load of 12 kPa and a rotation speed of 50 rpm for 1,000 minutes was measured. In addition, the appearance of the leather-like sheet base material after the wear test was visually observed and scored based on the following criteria.
[Evaluation criteria for wear resistance]
5 points: No wear at all and no change.
4 points: There is almost no wear and almost no change.
3 points: Some wear is observed.
2 points: There is considerable wear.
1 point: Abrasion is severe.

(Vi) Texture of suede leather-like sheet:
Touching the buffing surface of the dyed suede-like leather-like sheet obtained in the following examples or comparative examples by hand to make a smooth touch of natural leather suede (good), smooth of natural leather suede-like The case where there was not was evaluated as a defect (x).

(VI) Morphological stability of leather-like sheet base material It was measured according to the constant load elongation measurement and the residual strain ratio measurement described in the test method (JASO M 403-88, Japan Society for Automotive Engineers) of the cloth material for sheet skin.

<< Spinning Examples 1 to 4 >> [Production of polyester, spinning and production of staples]
(1) Titanium dioxide is added to terephthalic acid and ethylene glycol in a proportion of 0.04% by mass based on the mass of terephthalic acid, and antimony trioxide is added in a proportion of 500 ppm based on the mass of terephthalic acid. A low polymer was produced by heating under a condition of 0.0 Pa and carrying out an esterification reaction until the esterification rate reached 95% or more. This low polymer and reactive phosphorus-based flame retardant (“M-Ester” manufactured by Sanko Co., Ltd., molecular weight 434, phosphorus atom content 7 mass%) was added in the proportions shown in Table 1 below and mixed thoroughly. Thereafter, melt polymerization was performed at a temperature of 280 ° C. under a reduced pressure of 40.0 Pa to produce a prepolymer having an intrinsic viscosity of 0.65 dl / g, which was extruded from a nozzle into a strand shape and cut into a cylindrical chip. This chip was pre-dried at 120 ° C. for 2 hours, and then subjected to solid state polymerization at 210 ° C. for 20 hours under a reduced pressure of 13.3 Pa or less, and the polyester having a phosphorus atom concentration of 0 ppm shown in Table 1 below, and Phosphorus copolyesters having a phosphorus atom concentration of 3,000 ppm, 6,000 ppm, 8,000 ppm or 12,000 ppm were produced, respectively.

(2) High fluidity low density polyethylene ("Mirason FL-60" manufactured by Mitsui Chemicals, MFR = 70 g / 10 min) using the polyester or phosphorus atom copolymerized polyester obtained in (1) above as an island component Was used as a sea component, and a melt composite spinning was performed at 300 ° C. with a mass ratio of polyester: polyethylene = 65: 35 and 50 islands to produce a sea-island composite spun fiber, and then in warm water at 75 ° C. After stretching 2.5 times, applying a fiber oil agent, drying by applying mechanical crimping, it was cut to a length of 51 mm to produce a staple having a single fiber fineness of 5.0 dtex.

(1) Using a sea-island type composite spun fiber staple obtained from spinning example 5 and containing polyester containing no phosphorus atoms as an island component, the fiber is opened with a card, and a desired basis weight and texture web are formed by a cross wrap method. A web having a weight per unit area of 100 g / m ² was manufactured by the method of obtaining the above.
(2) A web having a basis weight of 400 g / m ² was produced by the same method as in (1) using the sea-island type composite spun fiber staple containing the phosphorus copolymerized polyester obtained in Spinning Example 3 as an island component.
(3) The web obtained in the above (1) is pre-entangled with 600 bar / cm ² using a 1 barb needle, and the web obtained in (2) is used with a 1 barb needle. After the entanglement treatment at 40 punches / cm ² in advance, the phosphorus atom-containing compound copolymer polyester having a phosphorus atom concentration of 6000 ppm used in the spinning example 2 was used between the two nonwoven fabrics, and the fibers were spun and stretched. after phosphorus containing a compound copolymerized polyester fiber 55dtex / 48f, a fabric basis weight 60 g / ^{m 2} are laminated, for about 2500 punches / cm ² needle punching in total alternately with needles of one barb from both Thus, the two webs and the fabric were integrated by entanglement. At that time, the needle punch from the web side obtained in the above (1) is carried out to a depth at which the barb of the needle sufficiently penetrates the web obtained in the above (2), and the web side obtained in the above (2) The needle punch from is carried out to a depth at which the barb of the needle does not reach the surface opposite to the surface in contact with the fabric of the web obtained in (1) above. Obtained. Next, the obtained non-woven fabric for flame-retardant leather-like sheet base material is contracted in hot water at 90 ° C., then set to a dry width, and pressed with a calender roll in a heated state to smooth the surface. A non-woven fabric was used. The resulting nonwoven fabric had a basis weight of 770 g / m ² and an apparent density of 0.48 g / cm ³ .

(4) Water having an average particle diameter of 1 μm with respect to 100 parts by mass of a dimethylformamide (DMF) solution (solid content: 14% by mass) of polyurethane mainly composed of polycarbonate-based polyurethane (“Nipporan 990N” manufactured by Nippon Polyurethane Industry Co., Ltd.) 17.5 parts by mass of a liquid in which aluminum oxide was dispersed at a concentration of 40% by mass in DMF was added to prepare an aluminum hydroxide-containing polyurethane liquid (mass ratio of polyurethane: aluminum hydroxide = 100: 50).
(5) The aluminum hydroxide-containing polyurethane liquid prepared in (4) above is impregnated with the non-woven fabric obtained in (3) above, and then the non-woven fabric is taken out of the polyurethane liquid and coagulated bath [DMF / water = 30 / 20 (mass ratio)] after being wet coagulated and then taken out of the coagulation bath and immersed in hot toluene (temperature 90 ° C.) to form a nonwoven fabric in the sea-island composite spun fiber The sea component (polyethylene) is removed by elution to form ultrafine fibers, and a non-flammable polyester ultrafine fiber nonwoven fabric layer [layer (A)] containing aluminum hydroxide and flame retardant polyester ultrafine fibers A layer having a polyurethane containing aluminum hydroxide in a non-woven fabric layer [layer (B)], and aluminum hydroxide in a fabric layer made of flame-retardant polyester fiber Was prepared layer [layer (C)] The flame-retardant leather-like sheet substrate made of three layers of (thickness 1.2 mm) having a polyurethane having. The flame retardant leather-like sheet base material layer (A) and layer (B) thus obtained are both non-flame retardant polyester ultrafine fiber and flame retardant polyester ultrafine fiber that exist as ultrafine fiber bundles. The single fiber fineness was 0.2 dtex. Further, the mass ratio of the polyester ultrafine fiber and the polyester fiber to the polyurethane in the flame-retardant leather-like sheet base material was about 79:21, and there was a space between the polyester ultrafine fiber and the polyurethane. Moreover, when the cross section of the thickness direction of the obtained flame-retardant leather-like sheet base material was observed with the microscope, it was confirmed that many aluminum hydroxide particles exist in the inside of porous polyurethane.

(6) After buffing the surface of the layer (A) side of the flame-retardant leather-like sheet base material obtained in (5) above to be a desired hair foot, the surface is dyed under the following dyeing conditions. A suede-like leather-like sheet was produced.
[Dyeing conditions of suede leather-like sheet]
Dyeing: “Miketon Polyester Blue FBL” 3% owf
(Mitsui Chemicals)
Dye temperature: 120 ° C
Dye time: 60 minutes Bath ratio: 1:20
Dyeing machine: High-pressure liquid flow dyeing machine ["Tecsum Giken" MINI-JET D200 "]

(6) Flame retardancy of flame retardant leather-like sheet substrate obtained in (5) above and suede-like leather like sheet obtained in (6) above, flame retardant leather obtained in (5) above When the phosphorus atom concentration and wear resistance, constant load elongation rate and residual strain rate of the sheet base material and the texture of the suede leather-like sheet obtained in the above (6) were measured or evaluated by the above method, Table 2 shows the results.

(1) A web having a basis weight of 150 g / m ² was obtained in the same manner as in (1) of Example 1 by using a sea-island type composite spun fiber staple having an island component of the polyester containing no phosphorus atom obtained in Spinning Example 5. Manufactured.
(2) A web having a basis weight of 350 g / m ² was produced in the same manner as in (2) of Example 1 by using the sea-island type composite spun fiber staple using the phosphorus copolymerized polyester obtained in Spinning Example 4 as an island component. .
(3) The web obtained in the above (1) is pre-entangled with 600 bar / cm ² using a 1 barb needle, and the web obtained in (2) is used with a 1 barb needle. After performing the entanglement process in advance at 40 punches / cm ² , the phosphorus atom-containing compound copolymer polyester having a phosphorus atom concentration of 6000 ppm used in the spinning example 2 is used between the two nonwoven fabrics, and the spinning and stretching are performed. After laminating a 55 dtex / 48 f woven fabric having a weight of 60 g / m ² made of a fiber coated with an aqueous solution of polyvinyl alcohol applied to the phosphorous-containing compound copolymerized polyester fiber, the needle was formed in the same manner as in Example 3 (3). The nonwoven fabric for flame-retardant leather-like sheet base materials was obtained by punching. Subsequently, the nonwoven fabric for flame retardant leather-like sheet base material obtained was subjected to shrinkage treatment, drying width setting, and press treatment with a calender roll to produce a nonwoven fabric having a smooth surface (weight per unit area: 770 g / m ² , apparent density). 0.48 g / cm ³ ).

(4) Using the nonwoven fabric obtained in (3) above, the same operations as in (4) and (5) of Example 1 were performed, and aluminum hydroxide was formed in the nonwoven fabric layer made of non-flame-retardant polyester ultrafine fibers. A layer containing polyurethane (layer (A)), a non-woven fabric layer made of flame-retardant polyester ultrafine fibers, a layer containing polyurethane containing aluminum hydroxide (layer (B)), and a flame-retardant polyester fiber A flame-retardant leather-like sheet substrate (thickness: 1.2 mm) composed of three layers [layer (C)] having a polyurethane containing aluminum hydroxide in the fabric layer was produced. The flame retardant leather-like sheet base material layer (A) and layer (B) thus obtained are both non-flame retardant polyester ultrafine fiber and flame retardant polyester ultrafine fiber that exist as ultrafine fiber bundles. The single fiber fineness was 0.2 dtex. Further, the mass ratio of the polyester ultrafine fiber and the polyester fiber to the polyurethane in the flame-retardant leather-like sheet base material is about 79:21, and there is a space between the polyester ultrafine fiber and the polyester fiber and the polyurethane. there were. Moreover, when the cross section of the thickness direction of the obtained flame-retardant leather-like sheet base material was observed with the microscope, it was confirmed that many aluminum hydroxide particles exist in the inside of porous polyurethane.

(5) After buffing the surface on the layer (A) side of the flame-retardant leather-like sheet base material obtained in the above (4) to make a suede-like leather-like sheet in the same manner as in (6) of Example 1 A dyed suede leather-like sheet was produced by dyeing in the same manner as in Example 1 (6).
(6) Flame retardancy of flame retardant leather-like sheet substrate obtained in (4) above and suede-like leather like sheet obtained in (5) above, flame retardant leather obtained in (4) above When the above-mentioned method was used to measure or evaluate the phosphorus atom concentration and abrasion resistance, the constant load elongation rate and the residual strain rate of the sheet-like sheet base material and the texture of the suede-like leather-like sheet obtained in the above (5), Table 2 shows the results.

<< Comparative Example 1 >>
(1) A web having a basis weight of 250 g / m ² was obtained in the same manner as in (1) of Example 1 by using the sea-island type composite spun fiber staple containing the polyester containing no phosphorus atom obtained in Spinning Example 5 as an island component. Manufactured.
(2) A web having a basis weight of 250 g / m ² was produced in the same manner as in (2) of Example 1 by using the sea-island type composite spun fiber staple using the phosphorus copolymerized polyester obtained in Spinning Example 1 as an island component. .
(3) The web obtained in the above (1) is pre-entangled with 600 bar / cm ² using a 1 barb needle, and the web obtained in (2) is used with a 1 barb needle. After performing the entanglement process in advance at 40 punches / cm ² , the phosphorus atom-containing compound copolymer polyester having a phosphorus atom concentration of 3000 ppm used in the spinning example 1 is used for spinning and stretching between the two nonwoven fabrics. After laminating a 55 dtex / 48f woven fabric composed of a phosphorus-containing compound copolymerized polyester fiber and having a basis weight of 60 g / m ² , needle punching is performed in the same manner as in (3) of Example 1 for a leather-like sheet substrate. A nonwoven fabric was obtained. Next, the nonwoven fabric for leather-like sheet substrate thus obtained was subjected to shrinkage treatment, drying width setting, and press treatment with a calender roll to produce a nonwoven fabric with a smooth surface (weight per unit area 770 g / m ² , apparent density 0.48 g). / Cm ³ ).
(4) Water having an average particle diameter of 1 μm with respect to 100 parts by mass of a dimethylformamide (DMF) solution (solid content: 14% by mass) of polyurethane mainly composed of polycarbonate-based polyurethane (“Nipporan 990N” manufactured by Nippon Polyurethane Industry Co., Ltd.) 17.5 parts by mass of a liquid in which aluminum oxide was dispersed at a concentration of 40% by mass in DMF was added to prepare an aluminum hydroxide-containing polyurethane liquid (mass ratio of polyurethane: aluminum hydroxide = 100: 50).

(5) The aluminum hydroxide-containing polyurethane liquid prepared in (2) above is impregnated with the non-woven fabric obtained in (3) above, and then the non-woven fabric is taken out of the polyurethane liquid and coagulated bath [DMF / water = 30 / 20 (mass ratio)] after being wet coagulated and then taken out of the coagulation bath and immersed in hot toluene (temperature 90 ° C.) to form a nonwoven fabric in the sea-island composite spun fiber The sea component (polyethylene) is eluted and made into ultrafine fibers, and a nonwoven fabric made of polyester ultrafine fibers and a nonwoven fabric made of polyester fibers are integrated into a non-woven fabric with a polyurethane containing aluminum hydroxide having a thickness of 1.2 mm A leather-like sheet substrate was produced.
(6) The web-side surface produced in (1) above of the leather-like sheet substrate obtained in (5) above is buffed in the same manner as in (6) of Example 1 to obtain a suede-like leather-like sheet. Then, it dye | stained similarly to (6) of Example 1, and the dyed suede tone leather-like sheet | seat was manufactured.
(7) Flame retardancy of the leather-like sheet base material obtained in the above (5) and the suede-like leather-like sheet obtained in the above (6), phosphorus of the leather-like sheet base material obtained in the above (5) As shown in Table 2 below, the atomic concentration, wear resistance, constant load elongation, residual strain rate, and texture of the suede-like leather-like sheet obtained in (6) above were measured or evaluated by the methods described above. Met.

<< Comparative Example 2 >>
(1) A web having a basis weight of 100 g / m ² was obtained in the same manner as in (1) of Example 1 by using the sea-island type composite spun fiber staple having the island component of the polyester containing no phosphorus atom obtained in Spinning Example 5. Manufactured.
(2) A web having a basis weight of 400 g / m ² was produced in the same manner as in (2) of Example 1 by using the sea-island type composite spun fiber staple using the phosphorus copolymerized polyester obtained in Spinning Example 3 as an island component. .
(3) The web obtained in the above (1) is pre-entangled with 600 bar / cm ² using a 1 barb needle, and the web obtained in (2) is used with a 1 barb needle. After performing the entanglement process at 40 punch / cm ² in advance and laminating the two nonwoven fabrics, the needle punching of about 2500 punch / m ² in total is alternately performed using a 1 barb needle from both sides. A nonwoven fabric for leather-like sheet base material was obtained. Next, the nonwoven fabric for leather-like sheet base material obtained is subjected to shrinkage treatment in 90 ° C. hot water and drying width setting, and pressed with a calender roll in a heated state to produce a nonwoven fabric with a smooth surface. did. The nonwoven fabric thus obtained had a basis weight of 700 g / m ² and an apparent density of 0.48 g / cm ³ .
(4) Using the non-woven fabric obtained in (3) above, impregnating the aluminum hydroxide-containing polyurethane solution and coagulating the polyurethane, and forming the non-woven fabric in the same manner as in (4) and (5) of Example 1. Leather-like sheet base with polyurethane containing aluminum hydroxide inside non-woven fabric made of flame retardant polyester extra fine fiber by elution and removal of sea component (polyethylene) in sea-island type composite spun fiber A material (1.2 mm thick) was produced.
(5) The web-side surface produced in (1) above of the leather-like sheet substrate obtained in (4) above is buffed in the same manner as in (6) of Example 1 to obtain a suede-like leather-like sheet. Then, it dye | stained similarly to (6) of Example 1, and the dyed suede tone leather-like sheet | seat was manufactured.
(6) Flame retardancy of the leather-like sheet substrate obtained in (4) above and the suede-like leather-like sheet obtained in (5) above, phosphorus of the leather-like sheet substrate obtained in (4) above As shown in Table 2 below, the atomic concentration, wear resistance, constant load elongation, residual strain rate, and texture of the suede-like leather-like sheet obtained in (5) above were measured or evaluated by the methods described above. Met.

<< Comparative Example 3 >>
(1) A web having a basis weight of 100 g / m ² was obtained in the same manner as in (1) of Example 1 by using the sea-island type composite spun fiber staple having the island component of the polyester containing no phosphorus atom obtained in Spinning Example 5. Manufactured.
(2) A web having a basis weight of 400 g / m ² was produced in the same manner as in (2) of Example 1 by using the sea-island type composite spun fiber staple using the phosphorus copolymerized polyester obtained in Spinning Example 3 as an island component. .
(3) The web obtained in the above (1) is pre-entangled at 40 punch / cm ² with a 1-needle, and the web obtained in (2) is subjected to a 1 barb needle. after the pre-entangling treatment with 40 punches / cm ² by using, between those two nonwoven, using a phosphorus-containing compound copolymerized polyester of the phosphorus atom concentration 6000ppm used for spinning examples 2, spinning, After a 55 dtex / 48 f woven fabric of stretched phosphorus-containing compound copolymerized polyester fibers and a fabric weight of 60 g / m ² was laminated, needle punching of about 2500 punches / cm ² in total was alternately performed using a 1 barb needle from both sides. The nonwoven fabric for leather-like sheet base materials was obtained by performing. At that time, the needle punch from the web side obtained in the above (1) and the needle punch from the web side obtained in the above (2) are both on the side opposite to the surface in contact with the fabric of the opposite side web. It went to the depth which penetrated to the surface. Next, the obtained nonwoven fabric for leather-like sheet base material is contracted in hot water at 90 ° C., then set in a dry width, and pressed with a calender roll in a heated state to produce a nonwoven fabric with a smooth surface. did. The nonwoven fabric thus obtained had a basis weight of 770 g / m ² and an apparent density of 0.48 g / cm ³ .

(4) Next, a leather-like sheet base material (thickness: 1.2 mm) containing polyurethane containing aluminum hydroxide (a flame retardant imparting component) was produced in the same manner as in Example 1.
(5) The web-side surface produced in (1) above of the leather-like sheet substrate obtained in (4) above is buffed in the same manner as in (6) of Example 1 to obtain a suede-like leather-like sheet. Then, it dye | stained similarly to (6) of Example 1, and the dyed suede tone leather-like sheet | seat was manufactured.
(6) Flame retardancy of the leather-like sheet substrate obtained in (4) above and the suede-like leather-like sheet obtained in (5) above, phosphorus of the leather-like sheet substrate obtained in (4) above As shown in Table 2 below, the atomic concentration, wear resistance, constant load elongation, residual strain rate, and texture of the suede-like leather-like sheet obtained in (5) above were measured or evaluated by the methods described above. Met.

  As seen in the results of Table 2 above, the flame-retardant leather-like sheet substrate using the nonwoven fabric for flame-retardant leather-like sheet substrate of the present invention and the leather-like sheet (suede-like leather-like sheet) obtained therefrom Are self-extinguishing and extremely flame retardant, have low surface loss due to wear, have no significant change in appearance even after a wear test, and have excellent shape stability. In addition, the texture is flexible, and it is a material suitable as an upholstery material for vehicle seats and interior products.

On the other hand, the leather-like sheet substrate of Comparative Example 1 contains an elastic polymer (D) containing a metal hydroxide because the phosphorus atom concentration of the polyester fibers constituting the B layer and the C layer is 3000 ppm or less. Despite being flammable, it is a material that is not suitable as a veneer for vehicle seats and interior products.
In addition, the leather-like sheet base material of Comparative Example 2 exhibits sufficient flame retardancy, but it is inferior in form stability because there is no woven or knitted fabric (C) in the nonwoven fabric. It is not a suitable material for upholstery materials such as interior products.
In addition, the leather-like sheet base material of Comparative Example 3 has the flame-retardant polyester ultrafine fiber on the back surface penetrating the non-flame-retardant polyester ultrafine fiber layer on the surface, and there are two types of fibers having different dyeability on the surface. The dyed suede-like leather-like sheet not only has an inferior-quality spot-like appearance, but also has poor flame retardancy with respect to the flame-retardant leather-like sheet substrate of the present invention and the leather-like sheet obtained therefrom. It is a material that cannot be said to be suitable as an upholstery material for vehicle seats or interior products.

The flame-retardant leather-like sheet base material of the present invention, and the leather-like sheet obtained therefrom, take advantage of the above-mentioned excellent characteristics, and have high flame retardancy, safety, good texture, appearance, high surface strength, excellent It is particularly useful as an upholstery material for vehicle seats such as railway vehicle seats, automobile seats, aircraft seats, and ship seats that require high form stability, and as an upholstery material for interior products such as sofas, cushions, and chairs. It can also be used effectively for a wide range of uses such as clothing, shoes, bags, accessory cases, and gloves.

Claims (4)

Non-woven fabric (A) mainly composed of ultrafine fiber-generating fiber (a ') capable of generating a fiber bundle composed of polyester ultrafine fiber (a) having a single fiber fineness of 0.5 dtex or less and containing no flame retardancy imparting component, containing phosphorus A fiber bundle composed of flame-retardant polyester ultrafine fibers (b) having a single fiber fineness of 0.5 dtex or less made of a copolyester obtained by copolymerizing a compound so that the phosphorus atom concentration is 6,000 to 50,000 ppm can be generated. Flame retardant polyester fiber comprising a non-woven fabric (B) mainly composed of ultrafine fiber-generating fibers (b ') and a copolyester obtained by copolymerizing a phosphorus-containing compound so that the phosphorus atom concentration is 6,000 to 50,000 ppm. (C) or a woven or knitted fabric (C) mainly composed of a fine fiber generating fiber (c ′) capable of generating the flame-retardant polyester fiber (c) is (A)-(C)-(B ) And the fibers constituting the nonwoven fabric (A) and the fibers constituting the nonwoven fabric (B) are intruded through the woven or knitted fabric (C) and entangled with each other to form a composite integrated nonwoven fabric. And the ultrafine fiber generation type | mold fiber (b ') which comprises a nonwoven fabric (B) has not reached the surface on the opposite side to the surface which contact | connects the woven / knitted fabric (C) of a nonwoven fabric (A) substantially. However, the ultrafine fiber generating fiber (a ′) constituting the non-woven fabric (A) reaches the surface opposite to the surface of the non-woven fabric (B) in contact with the woven or knitted fabric (C). Nonwoven fabric for leather-like sheet base material. The flame retardant leather-like leather according to claim 1, wherein the phosphorus atom concentration with respect to the total mass of the polyester extra fine fiber (a), the flame retardant polyester extra fine fiber (b) and the flame retardant polyester fiber (c) is 3,000 ppm or more. Nonwoven fabric for sheet base material. A non-woven fabric for a flame-retardant leather-like sheet substrate according to claim 1 or 2, comprising a polyester extra-fine fiber (a), a flame-retardant polyester extra-fine fiber (b), and a flame-retardant polyester fiber (c). A flame-retardant leather-like sheet base material in which the elastic polymer (D) is filled in a proportion of 5 to 50% with respect to the total fiber mass inside the formed nonwoven fabric. The flame-retardant leather-like sheet base material according to claim 3, wherein the metal hydroxide is contained in a proportion of 10 to 200% with respect to the mass of the elastic polymer (D).