TWI828830B - Velvety artificial leather and composite materials - Google Patents

Abstract

A pile-like artificial leather, which contains a fiber entangled body containing ultrafine fibers with a fineness of 0.5 dtex or less, and a polymer elastomer such as polyurethane impregnated into the fiber entangled body, and has ultrafine fibers. The main surface of the raised pile surface, and the thickness is 0.25~1.5mm. Furthermore, it further contains phosphorus-based flame retardant particles adhered to a polymer elastomer such as polyurethane, and the phosphorus-based flame retardant particles are distributed in a range of thickness 200 μm or less from the back surface with respect to the main surface. Furthermore, the phosphorus-based flame retardant particles have an average particle diameter of 0.1 to 30 μm, a phosphorus atom content of 14% by mass or more, a solubility in water of 30°C of 0.2% by mass or less, and a melting point or decomposition temperature when the melting point does not exist. Above 150°C, the content of phosphorus-based flame retardant particles is 1 to 6 mass% in terms of phosphorus atoms.

Description

Velvet artificial leather and composite materials

The present invention relates to a pile-like artificial leather that has both flame retardancy and excellent surface quality, and a composite material using the same.

Conventionally, it has been known to raise one side of an artificial leather fabric by impregnating a fiber entangled body such as a nonwoven fabric with a polymer elastomer to obtain a pile-like artificial leather having an appearance like suede leather. Velvety artificial leather is used as a material for shoes, clothing, gloves, bags, balls, etc., or as an interior material for buildings or vehicles. Compared with natural leather such as suede leather, suede-like artificial leather has the advantages of stable quality, excellent heat resistance, water resistance, and abrasion resistance, and is easy to maintain.

In addition, in recent years, imitation leather sheets using artificial leather, etc. have been used for the interior materials of public conveyors such as airplanes, ships, and railway vehicles, or for the interior materials of public buildings such as hotels and department stores. interior materials. For interior materials used in public places, in order to ensure safety in case of fire, they are required to have a high level of flame retardancy: self-extinguishing, low smoke generation, low heat generation, etc. In order to meet such flame retardant requirements, in the past, halogen-based flame retardants with high flame retardant properties were mostly blended into interior materials. However, since halogen flame retardants produce toxic halogen gas when burned, environmentally-related public interest groups and users recommend not to use halogen flame retardants. For example, the following Patent Documents 1 to 4 disclose a technology that uses a phosphorus-based flame retardant or a metal hydroxide-based flame retardant to make an imitation leather sheet flame-retardant. [Prior technical literature] [Patent Document]

Patent Document 1: Japanese Patent Application Publication No. Sho 56-050985 Patent Document 2: Japanese Patent Application Publication No. 2009-235628 Patent Document 3: Japanese Patent Application Publication No. 2013-227685 Patent Document 4: Japanese Patent Application Publication No. 2007-321280

[Problem to be solved by the invention]

Compared with the pile-like artificial leather that uses a knitted fabric of about 1 to 5 dtex fibers, also known as regular fibers, as a base material, a polymer elastomer is impregnated into the internal voids of a fiber entanglement of ultrafine fibers with a fineness of less than 1 dtex. The resulting velvety artificial leather has a smooth surface and a premium feel. However, the fluffy artificial leather containing extremely fine fibers has lower flame retardancy because the surface area of the fibers is larger than that of the fluffy artificial leather containing regular fibers.

In addition, it is difficult to provide sufficient flame retardancy to pile-like artificial leather containing ultrafine fibers without using a halogen-based flame retardant. Examples of non-halogen-based flame retardants that do not contain halogen include phosphorus-based flame retardants. Specific examples of the phosphorus-based flame retardant include polyphosphate inorganic salts such as metal polyphosphate, ammonium polyphosphate, polyphosphate urethane, and phosphates such as guanidine phosphate. However, polyphosphoric acid inorganic salts or phosphates have relatively high water solubility, so they may swell or dissolve due to moisture, water, or heat in the environment in which they are used, or may cause damage due to the drying process after being applied to the velvety artificial leather. When heat is applied, it tends to seep into the surface of the pile-like artificial leather. The flame retardant swells, dissolves or oozes to the surface of the downy artificial leather, causing the main surface of the downy surface to be whitened or colored by the flame retardant, which will damage the surface quality of the downy artificial leather. In addition, although the water solubility of aliphatic phosphates containing aromatic phosphates, aliphatic phosphonates, aliphatic cyclic phosphonates, etc. is relatively low, the flame retardant effect is insufficient and may damage the villi-like artificial products. Leather feel, or prone to bleeding, etc.

An object of the present invention is to provide a pile-like artificial leather that contains fiber entanglements of ultrafine fibers, does not impair the surface's high-quality feel, and uses a non-halogen system, and a composite material using the same. Flame retardant to impart flame retardancy. [Means used to solve problems]

One aspect of the present invention is a pile-like artificial leather, which contains a fiber entangled body containing ultrafine fibers with a fineness of 0.5 dtex or less, and a polymer elastomer impregnated and imparted to the fiber entangled body, and has a fiber entangled body that has made the ultrafine fibers elongate. The main surface of the velvet surface, and the thickness is 0.25~1.5mm. Furthermore, it further contains phosphorus-based flame retardant particles attached to the above-mentioned polymer elastomer, and the phosphorus-based flame retardant particles are distributed in a range with a thickness of 200 μm or less from the back surface with respect to the main surface.

The average particle size of the phosphorus-based flame retardant particles is 0.1 to 30 μm, preferably 0.5 to 30 μm, the phosphorus atom content is more than 14 mass%, the solubility in water at 30°C is less than 0.2 mass%, and the melting point or melting point does not exist The decomposition temperature is above 150℃. Furthermore, the content ratio of the phosphorus-based flame retardant particles in the downy artificial leather is 1 to 6 mass % in terms of phosphorus atoms.

According to such a pile-like artificial leather, a pile-like artificial leather containing a fiber entanglement of ultrafine fibers can be obtained, in which the phosphorus-based flame retardant particles as described above are preferentially present in a high concentration relative to the fibers forming the pile-like artificial leather. The main surface of the appearance is the back side, which is the opposite side, and a fluffy artificial leather is obtained that does not impair the surface's high-quality feel and uses a non-halogen flame retardant to impart flame retardancy.

As the polymer elastomer, it is preferred to include polyurethane, which is a reaction product of a polyurethane raw material including a polymer polyol, an organic polyisocyanate, and a chain extender; More than 60% by mass of the polymer polyol is polycarbonate polyol, and the average repeating carbon number after removing the reactive functional groups is less than 6.5; the organic polyisocyanate includes 4,4'-dicyclohexylmethane diisocyanate and At least one member from the group consisting of 4,4'-diphenylmethane diisocyanate.

In addition, it is preferable that the downy artificial leather has a weight per unit area of 100 to 300 g/m ² .

As the phosphorus-based flame retardant particles, particularly preferred are organic phosphinic acid metal salts, aromatic phosphonic acid esters, and phosphoric acid ester amide. In particular, when the phosphorus-based flame retardant particles contain at least one selected from the group consisting of dialkylphosphinic acid metal salts and monoalkylphosphinic acid metal salts, the phosphorus atom has high water resistance and heat resistance, and It is better from the viewpoint of high content rate and high flame retardant effect.

In addition, from the viewpoint of less impairing the high quality of the surface, it is preferable that the pile-like artificial leather is one in which 90 to 100 mass % of the phosphorus-based flame retardant particles are present in the range of a thickness of 200 μm or less from the back of the pile-like artificial leather. .

In addition, from the viewpoint of fully suppressing the decrease in flame retardancy caused by the polymer elastomer, the preferred material for the fluffy artificial leather is: the phosphorus-based flame retardant in the total amount of the phosphorus-based flame retardant particles and the polymer elastomer. The content ratio of the fuel particles is 5 to 20% by mass in terms of phosphorus atoms.

Furthermore, from the viewpoint that the phosphorus-based flame retardant particles tend to tend to be present in a thickness range of 200 μm or less, it is preferable that the pile-like artificial leather is: the polymer elastomer includes the first polymer elastomer present in the entire thickness cross section; The phosphorus-based flame retardant particles are attached to the second polymer elastomer that tends to exist in a range of 200 μm or less in thickness from the back of the pile-like artificial leather.

In addition, since the influence of the second polymer elastomer on reducing the flame retardancy is small, it is preferable that the fluffy artificial leather is composed of: the total amount of the phosphorus-based flame retardant particles and the second polymer elastomer. The content ratio of the phosphorus-based flame retardant particles is 10 to 30% by mass in terms of phosphorus atoms.

Furthermore, another aspect of the present invention is a composite material in which an interior base material is bonded to the back of any of the above-described pile-like artificial leathers with an adhesive. Such a composite material is used as an interior material or exterior material with a surface decorated with fluffy artificial leather, and has both flame retardancy and an excellent surface quality.

For example, the above composite material system can achieve a total heat generation (THR) of less than 10MJ/ ^m2 , a maximum heat generation (PHRR) of less than 250kW/ ^m2 , or a maximum average rate of heat dissipation (MARHE) of 90kW/ ^m2. the following. [Effects of the invention]

According to the present invention, it is possible to obtain a pile-like artificial leather, which is a pile-like artificial leather containing a fiber entanglement of ultrafine fibers, does not impair the surface's high-quality feel, and uses a non-halogen system, and a composite material using the same. flame retardant.

[Form used to implement the invention]

The pile-like artificial leather of this embodiment contains a fiber entangled body containing ultrafine fibers with a fineness of 0.5 dtex or less, and a polymer elastomer impregnated and provided to the fiber entangled body, and has piles of the ultrafine fibers. The main surface is velvety artificial leather with a thickness of 0.25 to 1.5mm. Furthermore, it further contains phosphorus-based flame retardant particles attached to the above-mentioned polymer elastomer, and the phosphorus-based flame retardant particles are distributed in a range with a thickness of 200 μm or less from the back surface with respect to the main surface.

The polymer elastic system imparts morphological stability to the fiber entanglement and gives a high-quality feel to the pile surface. Examples of polymer elastomers include polyurethane, acrylonitrile elastomer, olefin elastomer, polyester elastomer, polyamide elastomer, acrylic elastomer, and the like. These systems can be used individually or in combination of two or more types. Among these, polyurethane is preferred.

As the polymer elastomer, a particularly preferred polyurethane is a polyurethane containing a polymer polyol, an organic polyisocyanate, and a chain extender. The reaction product of the ester raw material; more than 60% by mass of the polymer polyol is polycarbonate polyol, and the average repeating carbon number after removing the reactive functional groups is less than 6.5; the organic polyisocyanate contains 4,4'- At least one kind from the group consisting of dicyclohexylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate.

In addition, the phosphorus-based flame retardant particles have an average particle diameter of 0.1 to 30 μm, a phosphorus atom content of 14% by mass or more, a solubility in water of 30°C of 0.2% by mass or less, and a melting point or decomposition temperature when the melting point does not exist. Above 150℃. Furthermore, the downy artificial leather contains phosphorus-based flame retardant particles at a content ratio of 1 to 6 mass % in terms of phosphorus atoms.

For example, the pile-like artificial leather is made by having a fiber entangled body containing ultrafine fibers with a fineness of 0.5 dtex or less, and a first polymer elastomer impregnated into the fiber entangled body, and having the ultrafine fibers raised. A treatment liquid containing phosphorus-based flame retardant particles and a second polymer elastomer is applied to the back of the main surface of a fleece-like artificial leather fabric with a thickness of 0.25 to 1.5 mm, and then dried. The phosphorus-based flame retardant particles are distributed in a range of 200 μm or less in thickness from the back surface through flame retardant treatment.

From the viewpoint of fully maintaining high flame retardancy, the phosphorus-based flame retardant particles are unlikely to affect the appearance or feel of the pile surface, and are unlikely to further degrade the surface's high-quality feel, the weight per unit area of the pile-like artificial leather is preferred. It is 100～600g/m ² , more preferably 100～300g/m ² , still more preferably 170～300g/m ² , particularly preferably 170～250g/m ² .

Examples of fiber entangled bodies containing ultrafine fibers with a fineness of 0.5 dtex or less include fiber structures such as nonwoven fabrics, woven fabrics, knitted fabrics, etc. containing ultrafine fibers with a fineness of 0.5 dtex or less. Among these, nonwoven fabrics made of ultrafine fibers are particularly advantageous in terms of obtaining a pile-like artificial leather that is excellent in softness and fullness due to its high homogeneity. In this embodiment, the fiber entangled body of ultrafine fibers will be described in detail with respect to a nonwoven fabric of ultrafine fibers as a representative example.

An example of a method for producing ultrafine fiber nonwoven fabrics is to melt-spun the island-in-the-sea type composite fiber to produce a web, and then entangle the web and then selectively remove the sea component from the island-in-the-sea type composite fiber. , a manufacturing method to form extremely fine fibers. An example of a method for manufacturing the net body is to collect long fiber sea-island composite fibers spun by a spunbonding method or the like on a net without cutting them to form a long fiber net. The method of forming a body; or the method of cutting long fibers into short fibers to form a short fiber network, etc. Among these, the long fiber mesh is particularly preferred because of its excellent density and fullness. In addition, the formed network may be subjected to a melt-bonding process in order to provide morphological stability. Examples of the entanglement treatment include stacking about 5 to 100 meshes and performing needle punching or high-pressure water flow treatment. In addition, in any step before removing the sea component of the sea-island type composite fiber and forming ultrafine fibers, the sea-island type composite fiber can be densified by subjecting the sea-island type composite fiber to fiber shrinkage treatment such as heat shrinkage using water vapor, thereby improving the A sense of fulfillment.

In this embodiment, the case of using island-in-the-sea type composite fiber is explained in detail. However, ultrafine fiber-generating fibers other than island-in-the-sea type composite fiber can also be used, or ultrafine fiber-generating fibers can be directly spun without using ultrafine fiber-generating fibers. Non-woven fabric. Specific examples of ultrafine fiber-producing fibers other than sea-island composite fibers can be used without particular limitations as long as they are fibers that can form ultrafine fibers. For example, a plurality of ultrafine fibers can be lightly adhered to each other immediately after spinning. A peel-and-split type fiber that is formed and unraveled by mechanical operation to form a plurality of extremely fine fibers; or a petal-type fiber that is formed by alternately gathering a plurality of resins into a petal shape in the melt spinning step.

The resin system of the island component used to form the island-in-the-sea composite fiber forming ultrafine fibers is not particularly limited. Specific examples include: polyethylene terephthalate (PET), isophthalic acid-modified PET, sulfoisophthalic acid-modified PET, polybutylene terephthalate, polyp- Aromatic polyesters such as hexylene phthalate; polylactic acid, polyethylene succinate, polybutylene succinate, polybutylene succinate adipate, polyhydroxybutyrate-polyester Aliphatic polyesters such as hydroxyvalerate resin; polyamides such as 6-polyamide, polyamide 66, polyamide 10, polyamide 11, polyamide 12, polyamide 6-12, etc. Nylon); polyolefins such as polypropylene, polyethylene, polybutylene, polymethylpentene, chlorinated polyolefins, etc. These systems can be used individually or in combination of two or more types. Among these, preferred are PET or modified PET, polylactic acid, polyamide 6, polyamide 12, polyamide 6-12, polypropylene, etc.

In addition, as the resin of the sea component forming the sea-island composite fiber, a resin different from the resin of the island component in solubility in a solvent or decomposability in a decomposing agent can be selected. Specific examples of the thermoplastic resin constituting the sea component include water-soluble polyvinyl alcohol, polyethylene, polypropylene, polystyrene, ethylene-propylene resin, ethylene-vinyl acetate resin, styrene-vinyl resin, Styrene-acrylic resin, etc.

The sea component of the sea-island composite fiber is dissolved or decomposed and removed at an appropriate stage after forming the mesh body. By such decomposition and removal or dissolution and extraction, the sea-island composite fibers are fibrillated into ultrafine fibers, thereby forming ultrafine fibers in the form of fiber bundles.

The fineness of ultrafine fibers is 0.5 dtex or less, preferably 0.001 to 0.4 dtex, more preferably 0.01 to 0.3 dtex. When the fineness of ultrafine fibers exceeds 0.5 dtex, the high-quality feel of the pile surface is likely to decrease. In addition, the fineness can be determined by using a scanning electron microscope (SEM) to take a cross-section of the fluffy artificial leather in the thickness direction at a magnification of 2000 times to determine the cross-sectional area of a single fiber. From the ratio of the cross-sectional area to the resin that forms the ultra-fine fibers , calculate the fineness of a single fiber. The fineness system can be defined as the average value of the fineness of 100 single fibers calculated from everywhere in the captured image.

The first polymer elastic system is imparted entirely to the entire nonwoven fabric. The first polymer elastic system imparts morphological stability to the fiber entangled body containing ultrafine fibers with a fineness of 0.5 dtex or less by constraining ultrafine fibers, and imparts a high-quality feel to the pile surface. Examples of the first polymer elastomer include polyurethane, acrylonitrile elastomer, olefin elastomer, polyester elastomer, polyamide elastomer, acrylic elastomer, and the like. These systems can be used individually or in combination of two or more types. Among these, polyurethane is preferred.

In addition, polyurethane-based fibers tend to burn more easily than ultrafine fibers. In the pile-like artificial leather of this embodiment, by applying the flame retardant to the back side of the pile-like artificial leather, deterioration in the appearance of the pile surface caused by the addition of the flame retardant can be suppressed.

The use of polyurethane is particularly advantageous in that the flame retardancy of the pile surface can be improved by using a specific polyurethane. Such specific polyurethane includes polyurethane, which is a reaction product of a polyurethane raw material including a polymer polyol, an organic polyisocyanate, and a chain extender; 60% of the polymer polyol The mass % or more is polycarbonate polyol, and the average repeating carbon number after removing the reactive functional groups is less than 6.5; the organic polyisocyanate includes 4,4'-dicyclohexylmethane diisocyanate and 4,4'-diisocyanate. At least one member from the group consisting of phenylmethane diisocyanate. Such a polyurethane system has excellent self-extinguishing properties, has low calorific value and smoke generation, and exhibits a high level of flame retardancy.

Specific examples of the polycarbonate polyol include polyhexamethylene carbonate diol, poly(3-methyl-1,5-pentylene carbonate) diol, and polypentamethylene carbonate. Polycarbonate polyols such as ester diol, polytetramethylene carbonate diol, polycyclohexane carbonate diol and their copolymers.

In addition, as the polymer polyol, polymer polyols other than polycarbonate polyol may be included within the range of not exceeding 40% by mass. Specific examples of polymer polyols other than polycarbonate polyol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, poly(methyltetramethylene glycol), and the like. Polyether polyols and their copolymers; polyethylene adipate diol, polypropylene adipate diol, polypropylene adipate diol, Polybutylene adipate diol, polybutylene sebacate diol, polyhexamethylene adipate diol, poly(3-methyl-1,5-pentane adipate) Polyester polyols such as glycol, poly(3-methyl-1,5-pentane sebacate) glycol, polycaprolactone diol and their copolymers; polycarbonate with more than 6.5 carbon atoms Ester polyols; polyester carbonate polyols, etc. These systems can be used individually or in combination of two or more types.

The content ratio of the polycarbonate polyol contained in the polymer polyol used for the production of specific polyurethane is 60 mass% or more, preferably 70 mass% or more. When the content ratio of the polycarbonate polyol contained in the polymer polyol is less than 60% by mass, the calorific value and the amount of smoke generated by the polyurethane increase.

Furthermore, the average number of repeating carbon atoms after removing the reactive functional groups of the polymer polyol used in the production of the specific polyurethane is 6.5 or less, preferably 6.0 or less. When the average number of repeating carbon atoms in the polymer polyol after removing the reactive functional groups exceeds 6.5, the calorific value and smoke emission of the polyurethane will increase.

Here, the so-called average repeating carbon number of a polymer polyol after removing the reactive functional groups is defined as the carbonate group (-OCOO-) and ester group after removing the reactive functional groups in the polymer polyol reaction. The number of carbon atoms in the hydrocarbons contained in the repeating units of polymer polyols such as (-COO-) and ether groups (-O-). In addition, when two or more types of polymer polyols are used, the average number of repeating carbon atoms after removing the reactive functional groups is calculated by calculating the number of carbonate groups, ester groups, ether groups, etc., including two or more types after removing the reactive functional groups. The value obtained by averaging the number of carbon atoms in the hydrocarbons contained in the repeating units of polymer polyol.

The molecular weight of the polymer polyol is preferably an average molecular weight of 200 to 6000, more preferably 500 to 5000.

Furthermore, the organic polyisocyanate used in the production of specific polyurethane includes one selected from the group consisting of 4,4'-dicyclohexylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate. At least 1 species. Moreover, 60 mass % or more of the organic polyisocyanate, more preferably 70 mass % or more, especially 80 mass % or more, contains a compound selected from the group consisting of 4,4'-dicyclohexylmethane diisocyanate and 4,4'-diphenyl At least one type of the group consisting of methane diisocyanates is preferred in that it can obtain a polyurethane that is excellent in self-extinguishing properties and has low calorific value and low smoke generation.

In the polyurethane raw materials, in addition to polymer polyols, polyfunctional alcohols such as trifunctional alcohols or tetrafunctional alcohols, or short-chain alcohols such as ethylene glycol can also be used. These systems can be used individually or in combination of two or more types.

Moreover, in the polyurethane raw material, in addition to 4,4'-dicyclohexylmethane diisocyanate and 4,4'-diphenylmethane diisocyanate, other organic isocyanates can be used together. Specific examples of such organic isocyanates include hexamethylene diisocyanate, isophorone diisocyanate, and Non-yellowing diisocyanates such as aliphatic or alicyclic diisocyanates such as ethylene diisocyanate; 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, xylylene diisocyanate, polyurethane, etc. Aromatic diisocyanates, etc. Moreover, if necessary, polyfunctional isocyanates such as trifunctional isocyanate or tetrafunctional isocyanate or blocked polyfunctional isocyanate may be used together. These systems can be used individually or in combination of two or more types.

As a chain extender used in the production of specific polyurethane, a low-molecular compound having two or more active hydrogens is used. Specific examples of the chain extender include hydrazine, ethylenediamine, propylenediamine, hexamethylenediamine, nonamethylenediamine, xylylenediamine, and isophoronediamine. Amine, piperazine and its derivatives, diamines such as adipic acid dihydrazide and isophthalic acid dihydrazide; triamines such as diethylenetriamine; tetraamines such as triethylenetetramine; ethylene glycol , propylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,4-bis(β-hydroxyethoxy)benzene, 1,4-cyclohexanediol and other glycols; trihydroxy Tri-alcohols such as methylpropane; penta-alcohols such as pentaerythritol; amine-alcohols such as aminoethanol and aminopropyl propanol. These systems can be used individually or in combination of two or more types. Among these, from the viewpoint of excellent mechanical properties, it is preferable to use hydrazine or piperazine. , ethylenediamine, hexamethylenediamine, isophoronediamine and its derivatives, triamines such as diethylenetriamine, ethylene glycol, propylene glycol, 1,4-butanediol and its derivatives 2 or more combinations of them. In addition, during the chain elongation reaction, monoamines such as ethylamine, propylpropylamine, butylamine, and carboxyl group-containing monoamines such as 4-aminobutyric acid and 6-aminocaproic acid can also be used together with the chain elongation agent. Amine compounds; monohydric alcohols such as methanol, ethanol, propanol, butanol, etc. Among these, a chain extender having a carbon number of 6 or less after removing the reactive functional group is particularly preferred because it has excellent self-extinguishing properties and has a small calorific value and a small amount of smoke.

In addition, in order to control the water absorption of polyurethane or the adhesion or hardness of polyurethane to ultrafine fibers, it is also possible to add functionalities that contain two or more monomer units that form polyurethane in the molecule. Cross-linking agents with functional groups that can react, such as carbodiimide compounds, epoxy compounds, Self-crosslinking compounds such as oxazoline compounds, polyisocyanate compounds, and polyfunctional blocked isocyanate compounds form a crosslinked structure in polyurethane.

Examples of polyurethane emulsions include forced emulsification polyurethane emulsions emulsified by adding an emulsifier that does not have ionic groups in the polyurethane skeleton; or polyurethane emulsions in which Self-emulsifying polyurethane emulsion that emulsifies by self-emulsification and has ionic groups such as carboxyl groups, sulfonic acid groups, and ammonium groups in the skeleton; or emulsifiers that use an emulsifier in combination with ionic groups in the polyurethane skeleton. Polyurethane emulsion. For example, in order to introduce carboxyl groups into the polyurethane skeleton, 2,2-bis(hydroxymethyl)propionic acid, 2,2-bis(hydroxymethyl)butyric acid, 2,2-bis(hydroxymethyl)butyric acid, and A method of incorporating units of carboxyl-containing diols such as hydroxymethyl)valeric acid into the polyurethane skeleton.

For example, an emulsion of a polymer elastomer such as a polyurethane emulsion or a fiber entanglement of ultrafine fibers may be impregnated into a fiber entanglement of ultrafine fiber-generating fibers such as island-in-the-sea composite fiber used to form ultrafine fibers or a fiber entanglement of ultrafine fibers. After the solution of the polymer elastomer such as a polyurethane solution is solidified, the first polymer elastomer is imparted to the fiber entangled body. Examples of a method for impregnating the fiber entangled body with the emulsion or solution of the first polymer elastomer include a method using a knife coater, a rod coater, or a roll coater, or an impregnation method. In addition, when using emulsion, the polymer elastomer can be solidified by the following methods: heat treatment in a drying device at 50 to 200°C or heat treatment in a dryer after infrared heating; steam treatment A method of heat treatment in a dryer; or a method of heat treatment in a dryer after ultrasonic heating; and methods that combine these.

In addition, as the polyurethane emulsion, from the viewpoint of obtaining a soft feel, it is preferable to use a combination of a self-emulsifying polyurethane and a forced emulsification polyurethane. For example, use a polyurethane emulsion containing 20 to 100% by mass. Polyurethane emulsion consisting of 0% to 80% by mass of self-emulsifying polyurethane and forced-emulsifying polyurethane. Moreover, the dispersed average particle size of the polyurethane emulsion is preferably 0.01 to 1 μm, more preferably 0.03 to 0.5 μm.

When the fiber entangled body is impregnated with polyurethane emulsion and then dried, the emulsion migrates to the surface layer of the fiber entangled body, making it difficult to apply it uniformly in the thickness direction. In such a case, migration can be suppressed as follows, for example. Adjust the dispersed particle size of the emulsion; adjust the type or amount of ionic groups of the polyurethane; add ammonium salt whose pH changes due to the temperature of about 40 to 100°C to reduce the water dispersion stability; add 1 or 2 Valuable alkali metal salts or alkaline earth metal salts, nonionic emulsifiers, associative water-soluble thickeners, water-soluble polysiloxane compounds and other associative heat-sensitive gelling agents, or water-soluble polyurethane Acid ester compounds reduce water dispersion stability.

From the viewpoint of obtaining a soft hand and providing smooth surface touch or surface physical properties, the first polymer elastomer preferably has a 100% modulus of 0.5 to 7 MPa, more preferably 1 to 5 MPa. When the 100% modulus is too low, when the pile-like artificial leather is heated, the first polymer elastomer tends to soften and bind the ultrafine fibers, resulting in a reduction in the soft feel or smooth surface feel. In addition, when the 100% modulus is too high, the smooth surface feel of the plush artificial leather tends to be reduced or the hand feel becomes hard.

From the viewpoint of high flame retardancy, high-quality surface, morphological stability, and excellent surface properties, the proportion of the first polymer elastomer contained in the downy artificial leather is preferably 3 to 50% by mass. , more preferably 3 to 40 mass %, still more preferably 3 to 35 mass %, particularly preferably 7 to 25 mass %.

The fiber entangled system containing the first polymer elastomer is optionally subjected to moisture heat shrinkage or pressure treatment to adjust the apparent density, unit area weight or thickness, and is processed into a gray fabric of artificial leather. Then, the gray cloth of the artificial leather is sliced if necessary. Then, by polishing at least one side of the artificial leather fabric with contact polishing, emery polishing, or the like, a pile-like artificial leather fabric with a pile surface is produced.

Polishing is preferably performed using sandpaper or emery paper of about 120 to 600 grit, for example. In this way, the fibers on the polished surface are raised to produce a velvet-like artificial leather fabric having a nap surface on which ultrafine fibers are raised. The gray fabric of the velvety artificial leather can be further dyed, rubbed and softened, air impact softened, anti-seal brushed, anti-fouling, hydrophilized, lubricated, and softened as needed. Agent treatment, antioxidant treatment, ultraviolet absorber treatment, fluorescent agent treatment, etc.

The thickness of the gray fabric of the downy artificial leather is roughly equal to the thickness of the final obtained downy artificial leather. The thickness of the gray fabric of the downy artificial leather is 0.25 to 1.5 mm, preferably 0.3 to 1.0 mm, more preferably 0.4 to 1.0 mm. When the thickness of the downy artificial leather fabric exceeds 1.5 mm, it is difficult to obtain sufficient flame retardant effects.

Velvet artificial leather is made by coating a treatment liquid containing phosphorus-based flame retardant particles and a second polymer elastomer on the back of the pile surface of a gray fabric of 0.25 to 1.5 mm thickness with respect to the main surface. , is obtained by a flame retardant treatment that is performed by drying and imparting phosphorus-based flame retardant particles to a thickness range of 200 μm or less from the back surface.

Here, in the pile-like artificial leather, the phosphorus-based flame retardant particles are preferentially present in the range of a thickness of 200 μm or less from the back side with respect to the main surface, which means that the phosphorus-based flame retardant present in the pile-like artificial leather is Most of the particles (specifically, 90 to 100% by mass, or even 95 to 100% by mass of the phosphorus-based flame retardant particles) are present in a range with a thickness of 200 μm or less from the back surface with respect to the main surface. The thickness from the back surface to the main surface where the phosphorus-based flame retardant particles are biased is preferably 50 to 200 μm, more preferably 70 to 180 μm, and particularly preferably 100 to 150 μm. The thickness of the area where the phosphorus-based flame retardant particles of the pile-like artificial leather are biased can be confirmed by observing the cross section of the pile-like artificial leather in a direction parallel to the thickness direction with a scanning electron microscope. In addition, the thickness of the area where the phosphorus-based flame retardant particles are concentrated is compared to the thickness of the pile-like artificial leather in that it does not impair the surface's high-quality feel and can easily provide a high level of flame retardancy using a non-halogen flame retardant. The ratio of the total thickness is preferably 10 to 60%, more preferably 10 to 50%.

In this way, by setting the content ratio in terms of phosphorus atoms to 1 to 6% by mass, the phosphorus-based flame retardant particles are distributed in a range of 200 μm or less in thickness from the back of the pile-like artificial leather without damaging the surface quality. Sensitive, and uses non-halogen flame retardants to impart flame retardancy.

The content ratio of the phosphorus-based flame retardant particles that tend to be present in the thickness range of 200 μm or less from the back of the pile-like artificial leather in the pile-like artificial leather is 1 to 6 mass % in terms of phosphorus atoms, preferably 1.5 to 1.5%. 5.5% by mass. When the content ratio of phosphorus-based flame retardant particles in terms of phosphorus atoms is less than 1% by mass, it is difficult to obtain a high level of flame retardancy. In addition, when the phosphorus-based flame retardant particles contain more than 6 mass % in terms of phosphorus atoms, it may be difficult to fix the phosphorus-based flame retardant particles without falling off, and the phosphorus-based flame retardant particles may be oriented to a thickness of 200 μm or less from the back surface. The softness of the downy artificial leather is lost and the surface quality is reduced.

In addition, the phosphorus-based flame retardant particles contained in the downy artificial leather have an average particle diameter of 0.1 to 30 μm, a phosphorus atom content of 14% by mass or more, a solubility in water of 30°C of 0.2% by mass or less, and a melting point or equivalent. Particles of a flame-retardant compound containing phosphorus atoms that have a decomposition temperature of 150°C or higher when the melting point does not exist and are solid particles at room temperature.

The average particle diameter of the phosphorus-based flame retardant particles is preferably 0.1 to 30 μm, more preferably 0.5 to 30 μm, particularly preferably 0.5 to 15 μm, particularly preferably 1 to 10 μm. When the average particle diameter exceeds 30 μm, it becomes difficult to sufficiently penetrate the phosphorus-based flame retardant particles to the thickness from the back of the pile-like artificial leather so that the content ratio of the phosphorus-based flame retardant particles becomes 1 to 6 mass % in terms of phosphorus atom conversion ratio. In the range of 200 μm or less, the flame retardant effect tends to be insufficient. In addition, when the average particle diameter is less than 0.1 μm, the particles are likely to agglomerate and become unevenly dispersed, and uneven flame retardancy is likely to occur.

In addition, the phosphorus atom content of the phosphorus-based flame retardant particles is 14 mass% or more, preferably 15 mass% or more, and more preferably 20 mass% or more. In addition, the content is preferably 30 mass% or less, and more preferably 28 mass% or less. When the phosphorus atom content of the phosphorus-based flame retardant particles is less than 14% by mass, it becomes difficult to provide a high level of flame retardancy. In addition, when the phosphorus atom content of the phosphorus-based flame retardant particles is too high, the flame retardant is likely to fall off and adhere to the surface, which tends to adversely affect the surface appearance or fastness.

In addition, the solubility of the phosphorus-based flame retardant particles in water at 30° C. is 0.2% by mass or less, preferably 0.15% by mass or less. When using phosphorus-based flame retardant particles whose solubility in water at 30°C exceeds 0.2% by mass, they will absorb moisture during production or use, or tend to seep out to the pile surface when wet. In addition, the solubility of phosphorus-based flame retardant particles in 30°C water can be measured by adding phosphorus-based flame retardant particles in small amounts at a time to 100g of 30°C water. measured by its maximum mass.

In addition, during the production or use of the pile-like artificial leather, the flame retardant is less likely to seep out to the pile surface when exposed to hot water, or the dimensional change of the pile-like artificial leather caused by the moisture absorption of the flame retardant can be suppressed. From this point of view, the hot water solubility of the phosphorus-based flame retardant particles in hot water of 90°C is preferably 5 mass% or less, and more preferably 3 mass% or less. In addition, the hot water solubility of phosphorus-based flame retardant particles in 90°C hot water can be measured by adding phosphorus-based flame retardant particles in small amounts at a time to 100g of 90°C water, and measuring the soluble phosphorus-based flame retardant particles. Measured based on the maximum mass of flame retardant particles.

In addition, the phosphorus-based flame retardant particles have a melting point or a decomposition temperature in the absence of a melting point of 150° C. or higher, preferably 200° C. or higher, and are particulate solids at room temperature. When the melting point or the decomposition temperature when the melting point does not exist is lower than 150°C, the flame retardant will soften during the drying step after adding the flame retardant during the production of pile-like artificial leather, making it difficult to maintain the particle form. As a result, the phosphorus-based flame retardant particles will aggregate the ultrafine fibers, resulting in a reduction in the surface feel or hand feeling of the pile surface. In addition, when the downy artificial leather is burned, it becomes easy to melt and drip, making it difficult to maintain a high level of flame retardancy.

Here, the melting point of the phosphorus-based flame retardant particles is identified by the melting peak temperature of thermogravimetric differential thermal analysis (TG-DTA) or differential scanning calorimeter analysis (DSC). In addition, the decomposition temperature when the melting point does not exist is identified by the decomposition start temperature of thermogravimetric differential thermal analysis (TG-DTA). The measurement conditions are not particularly limited, but the measurement is performed in a nitrogen atmosphere at a temperature rise rate of 5 to 10° C./min.

Examples of phosphorus-based flame retardant particles include organic phosphinic acid metal salts such as dialkylphosphinic acid metal salts and monoalkylphosphinic acid metal salts; aromatic phosphonic acid esters; phosphate ester amide, etc. . These systems can be used individually or in combination of two or more types. Among these, dialkylphosphinic acid metal salt or monoalkylphosphinic acid metal salt is preferred from the viewpoint of high water resistance and heat resistance, high phosphorus atom content, and high flame retardant effect.

The second polymer elastomer used to fix the phosphorus-based flame retardant particles contained in the pile-like artificial leather may be the same as the first polymer elastomer, or may be different. Among these, polyurethane is preferable from the viewpoint of excellent physical properties in flat flushing. In addition, from the viewpoint of obtaining a soft feel and suppressing the flame retardant from falling off, the second polymer elastomer preferably has a 100% modulus of 0.5 to 5 MPa, more preferably 1 to 4 MPa.

There is no particular limitation on the method of applying a treatment liquid containing phosphorus-based flame retardant particles and a second polymer elastomer to the back surface of a velvety artificial leather fabric with a thickness of 0.25 to 1.5 mm. Specific examples include coating the back surface of the fabric of the pile-like artificial leather with phosphorus-based flame retardant particles and a second polymer while adjusting the coating amount or viscosity by, for example, gravure coating, direct coating, roller coating, or spray coating. Methods for treating elastomers.

It is easy for the phosphorus-based flame retardant particles and the second polymer elastomer to sink moderately from the back of the fabric of the pile-like artificial leather and tend to exist in a range with a thickness of 200 μm or less, thereby not damaging the high quality of the pile surface of the main surface. In order to impart high flame retardancy to the fluffy artificial leather, the viscosity of the treatment liquid containing phosphorus-based flame retardant particles and the second polymer elastomer is preferably 200 to 10000 mPa·sec, and more preferably 500 ~5000mPa・sec.

As the treatment liquid containing the second polymer elastomer, for example, it is preferable to use a treatment liquid prepared by dispersing phosphorus-based flame retardant particles in an emulsion of polyurethane. When using a polyurethane emulsion, the average particle size of the emulsion is preferably 10 μm or less, more preferably 5 μm. In addition, the drying temperature of the treatment liquid is preferably 100 to 160°C.

The content ratio of the phosphorus-based flame retardant particles in the total amount of the phosphorus-based flame retardant particles and the second polymer elastomer is 10 to 30 mass % in terms of phosphorus atoms, preferably 12 to 30 mass %, and more Preferably, it is 15-25% by mass. When the content ratio of the phosphorus-based flame retardant particles in the total amount of the phosphorus-based flame retardant particles and the second polymer elastomer is the above ratio, the flame retardancy of the second polymer elastomer is reduced due to combustion. The smaller the impact, the better.

Furthermore, the content ratio of the phosphorus-based flame retardant particles in the total amount of the phosphorus-based flame retardant particles and the second polymer elastomer is preferably in the range of 10 to 30 mass % in terms of phosphorus atoms, and the phosphorus-based flame retardant particles The mass of the particles is preferably 60 to 90% by mass, more preferably 70 to 85% by mass.

In addition, the proportion of the second polymer elastomer contained in the pile-like artificial leather is not particularly limited, but it is possible to sufficiently fix the phosphorus-based retardant while suppressing the decrease in flame retardancy due to the provision of the second polymer elastomer. From the perspective of fuel particles, 2 to 15 mass % is preferred, and 4 to 10 mass % is more preferred.

When the ultrafine fibers are fiber bundles derived from sea-island composite fibers, the polymer elastic system can be impregnated into the inside of the fiber bundles or attached to the outside of the fiber bundles. When the island-in-the-sea type composite fiber is processed into ultrafine fibers, the thermoplastic resin containing the sea component is removed from the island-in-the-sea type composite fiber to form voids inside the ultrafine fiber bundles. Therefore, the second polymer elastomer provided by subjecting the sea-island composite fibers to ultrafine fibers can easily impregnate the fiber bundles and constrain the ultrafine fibers used to form the fiber bundles. Therefore, the second polymer elastic system impregnated into the ultrafine fiber bundles helps to constrain the ultrafine fiber bundles and improve the shape retention of the fiber entangled body.

From the point of view of reducing the influence of the decrease in flame retardancy caused by the burning of polyurethane, the high content of the first polymer elastomer and the second polymer elastomer contained in the pile-like artificial leather The ratio of the total amount of molecular elastomer is preferably 2 to 40 mass%, more preferably 5 to 35 mass%.

Furthermore, from the viewpoint of excellent flame retardancy and smoothness of the downy artificial leather, the phosphorus-based flame retardant particles and the polymer elastomer including the first polymer elastomer and the second polymer elastomer have The content ratio of the phosphorus-based flame retardant particles in the total amount is preferably 5 to 20 mass % in terms of phosphorus atoms, and more preferably 6 to 20 mass %.

From the viewpoint of obtaining a fluffy artificial leather that is particularly excellent in self-extinguishing properties and a high-quality surface, the fluffy artificial leather contains polymer elasticity including the first polymeric elastomer and the second polymeric elastomer. The total unit area weight of the body is preferably 10 to 150 g/m ² , more preferably 10 to 100 g/m ² , and particularly preferably 10 to 50 g/m ² .

In order to improve the smoothness of the surface and make the surface smooth to the touch, it is also possible to apply soft processing to the pile-like artificial leather. Examples of the softening process include a method of closely adhering the elastomer sheet to the pile-like artificial leather, mechanically shrinking the elastomer sheet in the longitudinal direction (MD of the production line), and heat-treating and heat-setting the elastomer sheet in the shrunk state.

The thickness of the downy artificial leather is 0.25 to 1.5 mm, preferably 0.3 to 1.0 mm, more preferably 0.4 to 1.0 mm. When the thickness of the downy artificial leather is less than 0.25mm, the flame retardant is easily exposed on the surface, and the surface quality and surface feel are reduced. In addition, when the thickness of the downy artificial leather exceeds 1.5 mm, the flame retardancy decreases.

In addition, the apparent density of the downy artificial leather is preferably 0.25 to 0.75 in that the fiber density on the surface is high, the pile surface has a good fluffy feel or surface touch, and the flatness of the fullness and soft feel is excellent. g/cm ³ , more preferably 0.35 to 0.65 g/cm ³ .

For example, the pile-like artificial leather is preferably used as a wall decoration material in which the pile-like artificial leather and an interior base material (back panel) are bonded together with a composite adhesive. Specific examples of interior base materials include concrete, bricks, tiles, ceramic tiles, fiber-reinforced cement boards, glass fiber-mixed cement boards, calcium silicate boards, iron and steel, aluminum, metal plates, glass, and ash. Mud, mortar, stone, gypsum board, rock wool, glass wool board, wood wool cement board, hard wood wool cement board, wood wool cement board, pulp cement board, flame retardant plywood, etc. Among these, concrete, bricks, tiles, ceramic tiles, fiber-reinforced cement boards, glass fiber-mixed cement boards, and silicic acid tiles are preferable from the viewpoint of suppressing flammability in combination with pile-like artificial leather. Calcium board, steel, aluminum, metal plate, glass.

Examples of adhesives for composite use include starch-based adhesives, (alkyl) cellulose-based adhesives, vinyl acetate-based adhesives, ethylene vinyl acetate-based adhesives, acrylic resin-based adhesives, polyurethane-based adhesives, and chloroprene-based adhesives. Adhesives made of metal compounds such as phenol-based, nitrile-based, ester-based, polysiloxane-based, fluorine-based and copolymers or mixtures thereof, or metal salts or hydroxides. Among these, starch-based, (alkyl)cellulose-based, vinyl acetate-based, chloroprene-based, and phenol-based materials are preferable from the viewpoint of suppressing flammability in combination with pile-like artificial leather. Adhesives made from adhesives such as nitrile adhesive, fluorine adhesive, polysiloxane adhesive, copolymers or mixtures thereof, metal salts or hydroxides.

The flame retardancy of a composite material made by bonding the interior base material to the back of the pile-like artificial leather with an adhesive can be evaluated using an ISO5660-1 cone calorimeter. Examples of the flame retardancy evaluated by a combustion test using a cone calorimeter include the total calorific value of combustion (THR; MJ/m ² ) and the maximum value of the calorific value of combustion per unit area and unit time (PHRR ; kW/m ² ), maximum average rate of heat dissipation (MARHE; kW/m ² ).

Composite materials made by bonding interior base materials to the back of fluffy artificial leather with an adhesive can achieve a total heat generation (THR) of less than 10 MJ/m ² or even less than 8 MJ/m ² . In addition, the composite material of this embodiment is a composite material with a maximum heat generation rate (PHRR) of 250kW/m ² or less, or even 200kW/m ² or less. In addition, the composite material of this embodiment is a composite material that can achieve a maximum average rate of heat dissipation (MARHE; kW/m ² ) of 90 kW/m ² or less.

In addition, since the downy artificial leather has a high level of flame retardancy, a high-quality surface, a soft feel, and a substantial feel, it can be suitably used in public conveyors such as airplanes, ships, railways, and vehicles, as well as in hotels and department stores. Applications that require a high level of flame retardancy such as self-extinguishing, low heat generation, and low smoke generation, such as parts of public buildings such as companies, materials for sofas, or interior decoration of walls. [Example]

Hereinafter, the present invention will be described in more detail using examples. In addition, the scope of the present invention is not limited at all by the examples.

First, the evaluation method used in this example will be summarized and explained below.

(Surface high-end) Touch the velvet surface of the velvety artificial leather and judge based on the following criteria. A: The surface feels smooth and there is no rough touch caused by phosphorus flame retardant particles. B: The surface feels rough and has a poor sense of quality. C: It feels hard and has a poor sense of quality. D: During storage, the phosphorus-based flame retardant particles exuded and the surface turned white.

(Thickness, weight per unit area, apparent density) According to JIS L1913, the thickness (mm) and weight per unit area (g/cm ² ) of the downy artificial leather are measured by dividing the weight per unit area by the thickness and converting. Calculate the apparent density (g/cm ³ ).

(Measurement of the thickness of the area where the phosphorus-based flame retardant particles attached to the polymer elastomer are concentrated) Cut out the pile-like artificial leather in the thickness direction, select 10 points from the entire cross section in the thickness direction, and use a scanning electron microscope at a magnification of 100 times to focus on the area where the phosphorus-based flame retardant particles exist from the back. Thickness is measured at 10 points. Then, the average value of eight points, excluding the maximum and minimum thickness values, was used as the thickness where the phosphorus-based flame retardant particles tend to exist.

(Average particle size of phosphorus flame retardant particles) Cut out the pile-like artificial leather in the thickness direction, select 10 points from the entire cross section in the thickness direction, and use a scanning electron microscope at a magnification of 1000 times to select the area where the phosphorus-based flame retardant particles exist from the back. Measure the diameter of 10 particles. Then, the average value of the eight particle diameters excluding the maximum and minimum values was regarded as the average particle diameter of the phosphorus-based flame retardant particles.

(Vertical combustion test: self-extinguishing) For velvety artificial leather, the vertical method flame retardancy is measured in accordance with the US Fire Test Specifications for Aircraft Interior Materials in FAR25 Appendix F Part1(a)(1)(ii). Specifically, the pile-like artificial leather was cut into 50.8 mm×304.8 mm to prepare a test piece. Then, the test piece was fixed vertically to the sample holder of the combustion test device. Arrange the burner directly below one end of the test piece, and after it contacts the flame for 12 seconds, measure the burning distance, self-extinguishing time, and dripping self-extinguishing time of the test piece. Calculate the average of n=10.

(Horizontal combustion test) For pile-like artificial leather, measure the horizontal method burning test in accordance with the burning test specifications of FMVSS302. Specifically, the pile-like artificial leather was cut into 102 mm × 356 mm, and a test piece with a marking line drawn on 38 mm from one end of the sample was produced. Then, the test piece was fixed horizontally to the sample holder of the combustion test device. Arrange a burner on one end of the sample on the side of the test piece with the marked line, and then measure the burning distance and burning time of the test piece after it is exposed to the flame for 15 seconds. Calculate the average of n=10. When self-extinguishing before the marking line, it is regarded as self-extinguishing before the marking line (SE). When it exceeds the marking line and the burning distance is less than 50mm and the burning time is less than 60 seconds, it is regarded as self-extinguishing. When the burning speed is less than 100mm/min, it is regarded as slow burning. flammability, the burning speed of 100mm/min or above is regarded as flammability.

〈Evaluation of composite materials with velvety artificial leather〉 The composite material composed of the downy artificial leather was evaluated according to each of the following evaluation methods.

(Combustion calorific value test) Using starch vinyl acetate adhesive (solid content 65g/m ² ) as an interior material for wall decoration, velvety artificial leather was adhered to calcium silicate with a thickness of 11mm and a density of 870kg/m ³ Plates, manufacturing composite materials. Using the cone calorimeter method of ISO5660-1, use a 50kW/ ^m2 heater to heat and burn for 20 minutes, and measure the total calorific value (THR), maximum calorific value (PHRR), and peak calorific value after 20 minutes. Maximum average rate of heat dissipation (MARHE) over time at 200kW.

(Combustion smoke test) Using starch vinyl acetate adhesive (solid content 65g/m ² ) as an interior material for wall decoration, velvety artificial leather was adhered to calcium silicate with a thickness of 11mm and a density of 870kg/m ³ Plates, manufacturing composite materials. Using the cone calorimeter method of ISO5660-1, use a 50kW/ ^m2 heater to heat and burn for 20 minutes, and measure the smoke production increase concentration (SPR).

[Example 1] Using water-soluble thermoplastic polyvinyl alcohol (PVA) as the sea component and isophthalic acid-modified polyethylene terephthalate as the island component resin, the sea-island type composite fiber is melt-spun. Specifically, the molten resin of the sea component resin and the island component resin were respectively supplied to a composite spinning spinneret equipped with a nozzle hole for forming a cross section in which 25 island component resins were distributed in the sea component resin. The nozzle hole spits out the molten fiber of the island-in-the-sea composite fiber. At this time, the pressure is adjusted so that the mass ratio of the sea component to the island component becomes sea component/island component = 25/75.

Then, the melted fiber of the island-in-the-sea type composite fiber was sucked and stretched by a suction device, and the island-in-the-sea type composite fiber with a fineness of 3.3 dtex was spun. The spun island-type composite fibers are continuously stacked on a movable mesh and lightly pressed by heated metal rollers to suppress surface fluff. Then, after the sea-island composite fiber was peeled off from the mesh, it was heated and pressed by passing it between a metal roller and a back roller, thereby obtaining a mesh with a basis weight of 31 g/m ² .

Next, using a cross-laying device, 8 layers of mesh were stacked so that the total weight per unit area became 300 g/m ² , and entanglement was performed by alternately needling from both sides. The weight per unit area of the mesh body after needling, that is, the entangled mesh body, is 440g/m ² .

Then, the entangled mesh body is subjected to moist heat shrinkage for 30 seconds under the conditions of 70°C and 50%RH humidity. The area shrinkage rate before and after moist heat shrinkage treatment was 47%.

Then, the shrunk entangled network is impregnated with an emulsion of the first polyurethane (first polymer elastomer) containing ammonium sulfate as a gelling agent, and then dried. The first polyurethane-based polycarbonate polyol is 100% and has an average repeat carbon number of 6 after removing the reactive functional groups. It is an organic compound of 4,4'-dicyclohexylmethane diisocyanate. It is the reaction product of polyisocyanate and chain extender, and is 100% self-emulsifying amorphous polycarbonate urethane with a modulus of 3.0MPa.

Then, the entangled network to which the first polyurethane is provided is immersed in hot water to dissolve and remove the PVA, thereby producing an artificial leather fabric containing 25 ultrafine fibers with a fineness of 0.1 dtex. Nonwoven fabric made of fiber bundles intertwined three-dimensionally. The content of the first polyurethane in the artificial leather fabric is 12% by mass.

Then, the artificial leather fabric is sliced and divided into two in the thickness direction, and the sliced surface is polished and processed into a suede-like artificial leather fabric having a suede-like suede surface. The thickness of the gray fabric of the downy artificial leather is 0.5mm, the weight per unit area is 250g/m ² , and the apparent density is 0.50g/cm ³ .

Then, a cycle dyeing machine is used to dye the velvety artificial leather fabric, and after drying, it is impregnated with a softener and further dried.

Then, on the sliced surface of the dyed pile-like artificial leather fabric, use a gravure coater equipped with a 35-mesh gravure roller to apply 2000 mPa· After applying the second polyurethane emulsion of sec to 110 g/m ² , the water was dried at 120°C. In addition, the dispersed particle size (median diameter: D ₅₀ ) of the particles of the metal salt of dialkylphosphinic acid measured by a laser diffraction/scattering particle size distribution measuring device was 4 μm, and the phosphorus atom content was 23.5 Mass%, the solubility in water at 30°C is less than 0.2% by mass, and the melting point and decomposition temperature exceed 250°C.

Moreover, the 2nd polyurethane emulsion contained 10 mass % of the 2nd polyurethane (2nd polymer elastomer) and 28 mass % of the dialkylphosphinic acid metal salt. The second polyurethane-based polycarbonate polyol is 100% and has an average repeat carbon number of 5.5 after removing the reactive functional groups. It is an organic compound of 4,4'-dicyclohexylmethane diisocyanate. It is the reaction product of polyisocyanate and chain extender, and is 100% forced emulsification amorphous polycarbonate urethane with a modulus of 1.0MPa.

Then, the flame-retardant treated pile-like artificial leather fabric is shrunk at a drum temperature of 120°C and a conveyance speed of 10 m/min. After shrinking it by 5.0% in the longitudinal direction (length direction), the surface is applied It is pre-sealed to obtain a suede-like suede-like artificial leather. The thickness of the velvety artificial leather is 0.52mm, the weight per unit area is 290g/m ² , and the apparent density is 0.56g/cm ³ .

Moreover, the pile-like artificial leather contains 10 mass % of a 1st polyurethane, 5 mass % of a 2nd polyurethane, and 15 mass % of dialkylphosphinic acid metal salt particles. As a result, the downy artificial leather contained a dialkylphosphinic acid metal salt at a content ratio of 2.6% by mass in terms of phosphorus atoms. In addition, the mass % in terms of phosphorus atoms was 10.3 mass % with respect to the total amount of the particles of the dialkylphosphinic acid metal salt, the first polyurethane, and the second polyurethane. In addition, the mass % in terms of phosphorus atoms was 17.3 mass % with respect to the total amount of particles of the second polyurethane and dialkylphosphinic acid metal salt.

Then, the obtained downy artificial leather was evaluated according to the above-mentioned evaluation method.

The above evaluation results are shown in Table 1 below.

[Table 1] Example number 1 2 3 4 5 6 7 8 9 10 11 very fine fiber Fineness (dtex) 0.1 0.1 0.1 0.1 0.4 0.2 0.2 0.4 0.001 0.1 0.1 Resin PET PET PET PET PET PET PET PET Ny PET PET No. 1 polyurethane Average number of repeating carbon atoms of polymer polyols (number) 6 6 6 6 4.9 6 6 4.9 4.9 6 5 Polycarbonate proportion of polymer polyol (mass %) 100 100 100 100 60 100 100 75 75 100 0 Diisocyanate ingredient※ H-MDI H-MDI H-MDI H-MDI MDI H-MDI H-MDI MDI/H-MDI MDI H-MDI IPDI Content ratio (C) (mass %) 10 9 19 11 10 10 9 20 31 10 19 2nd polyurethane Content ratio (D) (mass %) 5 11 5 3 5 4 4 3 5 5 5 Total unit area weight of the first polyurethane and the second polyurethane (g/m ² ) 42 55 78 37 39 42 38 98 102 11.3 62 Phosphorus flame retardant particles compound Dialkylphosphinic acid metal salt Dialkylphosphinic acid metal salt Dialkylphosphinic acid metal salt Dialkylphosphinic acid metal salt Monoalkylphosphinic acid metal salt Aromatic phosphonate Phosphate amide Dialkylphosphinic acid metal salt Dialkylphosphinic acid metal salt Dialkylphosphinic acid metal salt Dialkylphosphinic acid metal salt Content ratio (E) (mass %) 15 14 13 9 15 15 17 7 14 15 9 Dispersed particle size (D ₅₀ : μm) 4 4 4 4 0.5 5 20 4 4 4 4 Water solubility (%: 30℃) >0.2% >0.2% >0.2% >0.2% >0.1% >0.1% >0.1% >0.1% >0.1% >0.2% >0.2% Melting point, thermal decomposition temperature when there is no melting point (℃) >250℃ >250℃ >250℃ >250℃ >250℃ >250℃ >250℃ >250℃ >250℃ >250℃ >250℃ Phosphorus atom content (mass %) (F) 23.5 23.5 23.5 23.5 28 15 17 23.5 23.5 23.5 23.5 The phosphorus atom content ratio of the phosphorus flame retardant particles in the total amount of the phosphorus flame retardant particles and the second polymer elastomer ((E)*(F)/((D)+(E))) (mass %) 17.3 13.2 17.3 17.3 21.8 11.1 14 17.3 17.3 17.3 17.3 The phosphorus atom content ratio of the phosphorus flame retardant particles in the total amount of the phosphorus flame retardant particles and the first polymer elastomer and the second polymer elastomer ((E)*(F)/((C)+ (D)+(E)) (mass%) 10.3 8.6 6.9 7.8 12.6 6.6 8.6 5.8 5.6 6.0 7.6 Phosphorus atom conversion content ratio (E)*(F)/100 (mass %) 2.6 2.5 2.4 1.6 3.1 1.6 2.2 1.7 2.7 1.0 1.5 Average particle size of phosphorus flame retardant (SEM: μm) 4 4 4 4 0.5 5 20 4 4 4 4 Thickness from the back surface where the phosphorus-based flame retardant particles and the second polymer elastomer exist (L: μm) 150 150 120 180 100 180 80 150 180 150 150 Thickness of downy artificial leather (T: mm) 0.52 0.53 0.54 0.51 0.5 0.5 0.53 0.75 0.65 1.3 0.52 Ratio of thickness L to thickness T (%) 29 28 twenty two 35 20 36 15 20 28 12 29 Weight per unit area (g/m ² ) 290 300 320 275 280 280 300 435 280 725 290 Apparent density (g/cm ³ ) 0.56 0.56 0.59 0.54 0.56 0.56 0.57 0.58 0.43 0.56 0.56 High-end surface A A A A A A A A A A A Vertical combustion test (self-extinguishing) Burning distance(mm) 100 115 105 105 90 110 110 80 110 120 230 Self-extinguishing time (seconds) 1 3 2.5 1 1 1 2 3.5 1 6 28 Self-extinguishing time after dripping (seconds) 0 0 0 0 0 0 0 0 0 1.0 26 Horizontal combustion test burning rate SE SE SE SE SE SE SE SE SE SE slow burning ※ H-MDI＿4,4'-dicyclohexylmethane diisocyanateMDI_4,4'-diphenylmethane diisocyanateIPDI_Isophorone diisocyanate

[Example 2] Except in Example 1, a second polyurethane emulsion containing 22 mass% of the second polyurethane and 28 mass% of the dialkylphosphinic acid metal salt was used instead of 10 mass% of the second polyurethane emulsion. The second polyurethane was carried out in the same manner except for the second polyurethane emulsion of 28% by mass of dialkylphosphinic acid metal salt to obtain a pile-like artificial leather and evaluated. The results are shown in Table 1.

[Example 3] Except that in Example 1, an artificial leather fabric having a first polyurethane content of 24% by mass was used instead of an artificial leather fabric having a first polyurethane content of 12% by mass. , were carried out in the same manner to obtain vuff-like artificial leather, and evaluated. The results are shown in Table 1.

[Example 4] In addition to Example 1, the second polyurethane emulsion in which particles of a dialkylphosphinic acid metal salt which is a phosphorus-based flame retardant was dispersed was changed to 60 g/m Instead of coating in the manner of ² , instead of applying in the manner of 110 g/m ² , the process was carried out in the same manner to obtain a pile-like artificial leather and evaluated. The results are shown in Table 1.

[Example 5] In Example 1, instead of three-dimensionally entangling fiber bundles containing 25 fiber bundles of 0.1 dtex ultrafine fibers, a nonwoven fabric was formed in which fiber bundles containing 6 ultrafine fibers of 0.4 dtex were three-dimensionally entangled. Made of non-woven fabric. Moreover, as the first polyurethane, amorphous polycarbonate (average repeating carbon number after removing reactive functional groups is 5.5) and polyether polyol (average repeating carbon number after removing reactive functional groups is 4. ), a polymer polyol with a mass ratio of 60/40 and an average repeating carbon number of 4.9 after removing the reactive functional groups, an organic polyisocyanate of 4,4'-diphenylmethane diisocyanate, and a chain extender The product is 100% self-emulsifying amorphous polycarbonate urethane with a modulus of 3.0MPa. In addition, as the phosphorus-based flame retardant particles, the monoalkylphosphinic acid metal salt shown in Table 1 was used instead of the dialkylphosphinic acid metal salt. Otherwise, it was carried out similarly to Example 1, and the downy artificial leather was obtained and evaluated. The results are shown in Table 1.

[Example 6] In Example 1, a nonwoven fabric in which fiber bundles containing 0.2 dtex ultrafine fibers were three-dimensionally entangled was formed instead of three-dimensionally entangling fiber bundles containing 25 0.1 dtex ultrafine fibers. Non-woven fabric. Moreover, as the phosphorus-based flame retardant particles, the aromatic phosphonate ester shown in Table 1 was used instead of the dialkylphosphinic acid metal salt. This process was carried out similarly to the external system, and a pile-like artificial leather was obtained and evaluated. The results are shown in Table 1.

[Example 7] In Example 1, a nonwoven fabric in which fiber bundles containing 0.2 dtex ultrafine fibers were three-dimensionally entangled was formed instead of three-dimensionally entangling fiber bundles containing 25 0.1 dtex ultrafine fibers. Non-woven fabric. In addition, as the phosphorus-based flame retardant particles, the phosphate amide shown in Table 1 was used instead of the dialkylphosphinic acid metal salt. This process was carried out similarly to the external system, and a pile-like artificial leather was obtained and evaluated. The results are shown in Table 1.

[Example 8] Using polyethylene as the sea component resin and isophthalic acid-modified polyethylene terephthalate as the island component resin, the sea-island type composite fiber is melt-spun. Specifically, the molten resin of the sea component resin and the island component resin were respectively supplied to a composite spinning spinneret equipped with a nozzle hole for forming a cross section in which 25 island component resins were distributed in the sea component resin. The nozzle hole spits out the molten fiber of the island-in-the-sea composite fiber. At this time, the pressure is adjusted so that the mass ratio of the sea component to the island component becomes sea component/island component = 25/75.

Then, the molten fibers of the island-in-the-sea type composite fiber are sucked and stretched by a suction device, and the island-in-the-sea type composite fiber is spun. The spun island-type composite fibers are continuously stacked on a movable mesh and lightly pressed by heated metal rollers to suppress surface fluff. Then, after the sea-island composite fiber is peeled off from the mesh, it is heated and pressed by passing it between a metal roller and a back roller to obtain a mesh body.

Next, using a cross-laying device, 8 layers of mesh were stacked so that the total weight per unit area became 320 g/m ² , and entanglement was performed by alternately needling the mesh from both sides. Then, the entangled mesh body is subjected to moist heat shrinkage for 30 seconds under the conditions of 70°C and 50%RH humidity.

Then, the N,N-dimethylformamide solution of the first polyurethane is impregnated and imparted to the shrunk entangled network, and then immersed in a mixture of N,N-dimethylformamide and water. After solidifying the polyethylene in the liquid, the polyethylene is extracted with toluene and dried. Also, between the first polyurethane-based polycarbonate polyol (average repeating carbon number after removing reactive functional groups: 6) and polyester polyol (average repeating carbon number after removing reactive functional groups: 4) It is produced by the reaction of a polymer polyol with a mass ratio of 75/25 and an average repeat carbon number of 4.9 after removing the reactive functional groups, an organic polyisocyanate of 4,4'-diphenylmethane diisocyanate, and a chain extender. It is a 100% amorphous polycarbonate urethane with a modulus of 5.0MPa.

Otherwise, it was carried out similarly to Example 1, and the downy artificial leather was obtained and evaluated. The results are shown in Table 1.

[Example 9] Polyethylene was used as the sea component resin, and 6-nylon (6-polyamide) was used as the island component resin to melt-spun the sea-island type composite fiber. Specifically, polyethylene and 6-nylon are mixed at a mass ratio of 50/50 and melted, and the molten resin is supplied to a mixing spinneret and discharged from a nozzle hole. The average number of islands is about 600, and fibers of 5.5 dtex are obtained by stretching. After the fiber was crimped, it was cut into 51mm pieces and carded to obtain a short fiber network with a unit area weight of 100g/ ^m2 . Use a cross-laying device to stack 6 layers to make a mesh. After spraying oil, perform needle punching at 1500 knots/cm ² and then heat press to obtain an apparent density of 0.40g/cm ³ . Fiber entanglement with a thickness of 1.5mm.

Then, the first polyurethane is impregnated with a solution of N,N-dimethylformamide to the fiber entangled body, and then immersed in a mixture of N,N-dimethylformamide and water. After solidifying, the polyethylene is extracted with toluene and dried. Also, between the first polyurethane-based polycarbonate polyol (average repeating carbon number after removing reactive functional groups: 6) and polyester polyol (average repeating carbon number after removing reactive functional groups: 4) The reaction product of a polymer polyol with a mass ratio of 75/25 and an average repeating carbon number of 4.9 after removing the reactive functional groups, an organic polyisocyanate of 4,4'-diphenylmethane diisocyanate, and a chain extender. , and is 100% polyurethane with a modulus of 5.0MPa. In other systems, the process was carried out in the same manner as in Example 1, except that the dye was changed from disperse dyeing to gold-containing dyeing, to obtain and evaluate the downy artificial leather. The results are shown in Table 1.

[Example 10] Except that in Example 1, the fabric of the artificial leather with a thickness of 1.3 mm was used, it carried out similarly to obtain the downy artificial leather, and evaluated. The results are shown in Table 1.

[Example 11] Except in Example 3, the first polymer elastomer was changed to polyether-based polyurethane (the average repeating carbon number after removing the reactive functional group is 5), and the content of the phosphorus-based flame retardant particles was changed. The process was carried out in the same manner except that the ratio (E) was changed from 13% by mass to 9% by mass, to obtain and evaluate the downy artificial leather. The results are shown in Table 1.

[Comparative example 1] Except in Example 1, a second polyurethane emulsion containing 10 mass% of the second polyurethane and 6.8 mass% of the dialkylphosphinic acid metal salt was used instead of containing 10 mass% of the second polyurethane emulsion. The second polyurethane was carried out in the same manner except for the second polyurethane emulsion of 28% by mass of dialkylphosphinic acid metal salt to obtain a pile-like artificial leather and evaluated. In addition, the viscosity of the aqueous dispersion composed of the phosphorus-based flame retardant particles and the second polyurethane was 100 mPa·sec. The results are shown in Table 2.

[Table 2] Comparative example number 1 2 3 4 5 very fine fiber Fineness (dtex) 0.1 0.1 0.1 0.1 0.6 Resin PET PET PET PET PET No. 1 polyurethane Average number of repeating carbon atoms of polymer polyols (number) 6 6 6 6 9 Polycarbonate proportion of polymer polyol (mass %) 100 100 100 100 100 Diisocyanate ingredient※ H-MDI H-MDI H-MDI H-MDI HD Content ratio (C) (mass %) 11 10 10 10 19 2nd polyurethane Content ratio (D) (mass %) 6 0 5 5 5 Total unit area weight of the first polyurethane and the second polyurethane (g/m ² ) 33 twenty two 33 33 62 Phosphorus flame retardant particles compound Dialkylphosphinic acid metal salt Ammonium polyphosphate Ammonium polyphosphate Aromatic phosphate ester Dialkylphosphinic acid metal salt Content ratio (E) (mass %) 4 15 15 15 9 Dispersed particle size (D ₅₀ : μm) 4 20 20 0.5 4 Water solubility (%: 30℃) >0.2% 0.5 0.5 >0.2% >0.2% Melting point, thermal decomposition temperature when there is no melting point (℃) >250℃ >250℃ >250℃ 115℃ >250℃ Phosphorus atom content (mass %) (F) 23.5 31 31 10 23.5 The phosphorus atom content ratio of the phosphorus flame retardant particles in the total amount of the phosphorus flame retardant particles and the second polymer elastomer ((E)*(F)/((D)+(E))) (mass %) 9.5 31 22.8 7.4 17.3 The phosphorus atom content ratio of the phosphorus flame retardant particles in the total amount of the phosphorus flame retardant particles and the first polymer elastomer and the second polymer elastomer ((E)*(F)/((C)+ (D)+(E))) (mass%) 3.7 16 13.5 4.4 7.8 Phosphorus atom conversion content ratio (E)*(F)/100 (mass %) 0.7 3.5 3.4 1.1 1.6 Average particle size of phosphorus flame retardant (SEM: μm) 4 20 20 non-particle 4 Thickness from the back surface where the phosphorus-based flame retardant particles and the second polymer elastomer are present (L: μm) 300 100 100 200 150 Thickness of downy artificial leather (T: mm) 0.52 0.51 0.52 0.5 0.52 Ratio of thickness L to thickness T (%) 58 20 19 40 29 Weight per unit area (g/m ² ) 260 270 290 280 290 Apparent density (g/cm ³ ) 0.5 0.53 0.56 0.56 0.56 High-end surface B B,D C. D C A Vertical combustion test (self-extinguishing) Burning distance(mm) 260 120 150 280 280 Self-extinguishing time (seconds) 30 9 11 40 40 Self-extinguishing time after dripping (seconds) 8 0 4 20 30 Horizontal combustion test burning rate slow burning self-extinguishing self-extinguishing slow burning slow burning ※ H-MDI＿4,4'-dicyclohexylmethane diisocyanateMDI＿4,4'-diphenylmethane diisocyanateHD＿1,6-hexamethylene diisocyanate

[Comparative example 2] Except in Example 1, an aqueous dispersion containing 28% by mass of ammonium polyphosphate was used instead of the second solution containing 10% by mass of the second polyurethane and 28% by mass of the dialkylphosphinic acid metal salt. 2 Except for the polyurethane emulsion, the same process was carried out to obtain a pile-like artificial leather and evaluated. The results are shown in Table 2.

[Comparative example 3] Except that in Example 1, the ammonium polyphosphate shown in Table 2 was used instead of the dialkylphosphinic acid metal salt as the phosphorus-based flame retardant particles, the process was carried out in the same manner to obtain a fluffy artificial leather and evaluated. The results are shown in Table 2.

[Comparative example 4] Except that in Example 1, the aromatic phosphate shown in Table 2 was used as the phosphorus-based flame retardant particles instead of the dialkylphosphinic acid metal salt, the same procedure was carried out to obtain and evaluate the downy artificial leather. . The results are shown in Table 2. In addition, although the phosphorus-based flame retardant is treated in the form of an aqueous dispersion during the flame retardant treatment, when observed in the pile-like artificial leather, it is in the form of a resin film rather than in the form of particles.

[Comparative example 5] Except in Example 4, ultrafine fibers with an average fineness of 0.6 dtex produced by changing the number of island components of the spinneret from 25 to 4 were used, and the first polymer elastomer was changed to polycarbonate-based polyester. Except for urethane (average repeating carbon number after removing the reactive functional group: 9), the same procedure was performed to obtain a pile-like artificial leather and evaluated. The results are shown in Table 2.

Referring to Table 1 and Table 2, the pile-like artificial leather obtained in Examples 1 to 11 is a pile-like artificial leather with good surface quality, soft hand feeling, and flame retardancy. In addition, the pile-like artificial leather obtained in Examples 1 to 10 further has good self-extinguishing properties, has low smoke generation and combustion calorific value, and has an extremely high level of flame retardancy. On the other hand, the fluffy artificial leather obtained in Comparative Example 1, in which the phosphorus-based flame retardant particles were few and the flame retardant particles were present inside, had the phosphorus-based flame retardant exposed on the surface and had a poor surface quality. In addition, the fluffy artificial leather obtained in Comparative Example 2 using ammonium polyphosphate as the phosphorus-based flame retardant particles bleeds out over time and has a poor surface quality. In addition, the pile-like artificial leather obtained in Comparative Example 3 exuded over time and had a poor surface quality. In addition, Comparative Example 4 in which the phosphorus-based flame retardant particles were changed to aromatic phosphate ester had a hard feel.

[Example 12] Using PVA as the sea component resin and isophthalic acid-modified polyethylene terephthalate as the island component resin, the sea-island type composite fiber is melt-spun. Specifically, the molten resin of the sea component resin and the island component resin were respectively supplied to a composite spinning spinneret equipped with a nozzle hole for forming a cross section in which 25 island component resins were distributed in the sea component resin. The nozzle hole spits out the molten fiber of the island-in-the-sea composite fiber. At this time, the pressure is adjusted so that the mass ratio of the sea component to the island component becomes sea component/island component = 25/75.

Then, the melted fiber of the island-in-the-sea type composite fiber was sucked and stretched by a suction device, and the island-in-the-sea type composite fiber with a fineness of 3.3 dtex was spun. The spun island-type composite fibers are continuously stacked on a movable mesh and lightly pressed by heated metal rollers to suppress surface fluff. Then, after the sea-island composite fiber was peeled off from the mesh, it was hot-pressed by passing it between a metal roller and a back roller to obtain a mesh with a basis weight of 31 g/m ² .

Next, using a cross-laying device, 8 layers of mesh were stacked so that the total weight per unit area became 250 g/m ² , and entanglement was performed by alternately needling from both sides. The unit area weight of the entangled mesh body after needling is 350g/m ² .

Then, the entangled mesh body is subjected to moist heat shrinkage for 30 seconds under the conditions of 70°C and 50%RH humidity. The area shrinkage rate before and after moist heat shrinkage treatment was 47%.

Then, the shrunk entangled mesh is impregnated with an emulsion of the first polyurethane containing ammonium sulfate as a gelling agent, and then dried. The first polyurethane is a self-emulsifying amorphous polycarbonate urethane containing 4,4'-dicyclohexylmethane diisocyanate as a diisocyanate component and having a 100% modulus of 3.0 MPa.

Then, the entangled network to which the first polyurethane is provided is immersed in hot water to dissolve and remove the PVA, thereby producing an artificial leather fabric containing 25 ultrafine fibers with a fineness of 0.1 dtex. Nonwoven fabric made of fiber bundles intertwined three-dimensionally. The content of the first polyurethane in the artificial leather fabric is 12% by mass.

Then, the artificial leather fabric is sliced and divided into two in the thickness direction, and the sliced surface is polished and processed into a suede-like artificial leather fabric having a suede-like suede surface. The thickness of the gray fabric of the downy artificial leather is 0.35mm, the weight per unit area is 175g/m ² , and the apparent density is 0.50g/cm ³ .

Then, a cycle dyeing machine is used to dye the velvety artificial leather fabric, and after drying, it is impregnated with a softener and further dried.

Then, on the sliced surface of the dyed pile-like artificial leather fabric, use a gravure coater equipped with a 35-mesh gravure roller to apply 2000 mPa· After applying the second polyurethane emulsion of sec to 110 g/m ² , the water was dried at 120°C. In addition, the dispersed particle size (median diameter: D ₅₀ ) of the particles of the metal salt of dialkylphosphinic acid measured by a laser diffraction/scattering particle size distribution measuring device was 4 μm, and the phosphorus atom content was 23.5 Mass%, the solubility in water at 30°C is less than 0.2% by mass, and the melting point and decomposition temperature exceed 250°C.

Moreover, the 2nd polyurethane emulsion contained 10 mass % of the 2nd polyurethane and 28 mass % of the dialkylphosphinic acid metal salt. The second polyurethane is a forced emulsification-type amorphous polycarbonate urethane containing 4,4'-dicyclohexylmethane diisocyanate as a diisocyanate component and having a 100% modulus of 1.0 MPa.

Then, the flame-retardant treated pile-like artificial leather fabric is shrunk at a drum temperature of 120°C and a conveyance speed of 10 m/min. After shrinking it by 5.0% in the longitudinal direction (length direction), the surface is applied It is pre-sealed to obtain a suede-like suede-like artificial leather. The thickness of the velvety artificial leather is 0.4mm, the weight per unit area is 225g/m ² , and the apparent density is 0.56g/cm ³ .

Moreover, the downy artificial leather contains 10 mass % of the 1st polyurethane, 5 mass % of the 2nd polyurethane, and 14.4 mass % of dialkylphosphinic acid metal salt particles. As a result, the downy artificial leather contained a dialkylphosphinic acid metal salt at a content ratio of 3.4% by mass in terms of phosphorus atoms. In addition, the mass % in terms of phosphorus atoms was 11.5 mass % with respect to the total amount of the particles of the dialkylphosphinic acid metal salt, the first polyurethane, and the second polyurethane. Furthermore, the mass % in terms of phosphorus atoms was 17.4 mass % with respect to the total amount of particles of the second polyurethane and dialkylphosphinic acid metal salt.

Then, the obtained downy artificial leather was evaluated according to the above-mentioned evaluation method.

The above evaluation results are shown in Table 3 below.

[table 3] Example number 12 13 14 15 16 17 18 19 20 twenty one twenty two Plush artificial leather very fine fiber Fineness (dtex) 0.1 0.1 0.1 0.1 0.4 0.2 0.2 0.001 0.001 0.1 0.1 Resin PET PET PET PET PET PET PET Ny Ny PET PET No. 1 Polymer Elastomer Content rate (C) (mass %) 10 9 19 11 10 10 9 31 25 10.2 10 2nd Polymer Elastomer Content rate (D) (mass %) 5 11 5 3 5 4 4 5 9 3.9 5 Phosphorus flame retardant particles Content rate (E) (mass %) 14.4 13.6 12.6 8.9 14.5 14.4 17.2 13.8 25.2 10.8 14.4 compound Dialkylphosphinic acid metal salt Dialkylphosphinic acid metal salt Dialkylphosphinic acid metal salt Dialkylphosphinic acid metal salt Monoalkylphosphinic acid metal salt Aromatic phosphonate Phosphate amide Dialkylphosphinic acid metal salt Dialkylphosphinic acid metal salt Dialkylphosphinic acid metal salt Dialkylphosphinic acid metal salt Dispersed particle size (D ₅₀ : μm) 4 4 4 4 2 5 8 4 4 4 4 Water solubility (%: 30℃) >0.2% >0.2% >0.2% >0.2% >0.1% >0.1% >0.1% >0.1% >0.1% >0.1% >0.2% Melting point, thermal decomposition temperature when there is no melting point (℃) >250℃ >250℃ >250℃ >250℃ >250℃ >250℃ >250℃ >250℃ >250℃ >250℃ >250℃ Phosphorus atom content (mass %) (F) 23.5 23.5 23.5 23.5 28 15 17 23.5 23.5 23.5 23.5 Content ratio of phosphorus-based flame retardant particles in the total amount of phosphorus-based flame retardant particles and the second polymer elastomer ((E)*(F)/(D+E)) (mass %) 17.4 13.0 16.8 17.6 20.8 11.7 13.8 17.3 17.3 17.3 17.4 Content ratio of phosphorus-based flame retardant particles to the total amount of the first polymer elastomer and the second polymer elastomer ((E)*(F)/(C+D+E) )(mass%) 11.5 9.5 8.1 9.1 13.8 7.6 9.7 6.5 10.0 10.2 11.5 Phosphorus atom conversion content rate (E)*(F)/100 (mass %) 3.4 3.2 3.0 2.1 4.1 2.2 2.9 3.2 5.9 2.5 3.4 Average particle size of phosphorus flame retardant (SEM: μm) 4 4 4 4 2 5 8 4 4 4 4 Thickness from the back surface where the phosphorus-based flame retardant particles and the second polymer elastomer exist (L: μm) 150 150 120 180 180 180 120 180 180 150 190 Thickness of downy artificial leather (T: mm) 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.5 0.3 0.55 1.0 Ratio of thickness L to thickness T (%) 38 38 30 45 45 45 30 36 60 27 19 Weight per unit area g/ ^m2 225 235 256 205 220 210 230 225 128 300 300 apparent density g/cm ³ 0.56 0.56 0.59 0.54 0.56 0.56 0.57 0.45 0.43 0.54 0.30 High-end surface A A A A A A A A A A A Combustion test (self-extinguishing) Burning distance(mm) 110 125 115 115 105 120 120 120 85 95 120 Self-extinguishing time (seconds) 0 1.5 1 0 0 0 1 0 0 2 4 Self-extinguishing time after dripping (seconds) 0 0 0 0 0 0 0 0 0 0 0 composite materials adhesive Starch-vinyl acetate resin Vinyl acetate resin Chlorine-metal salt resin Nitrile-phenol resin Starch-vinyl acetate resin Starch-vinyl acetate resin Vinyl acetate resin Vinyl acetate resin Vinyl acetate resin Chlorine-metal salt resin Starch-vinyl acetate resin Interior base material (back panel) calcium silicate calcium silicate plaster calcium silicate plaster fiber cement calcium silicate calcium silicate plaster calcium silicate calcium silicate Smoke test Smoke concentration (SPR) 5 6 8 6.5 14 6 8 4 3 12 9 Combustion heat test Total calorific value (THR: MJ/m ²・20min) 6.5 7 9.5 8 8 7 8 7 7 10 8 Maximum heat generation (PHRR: kW/m ² ) 150 160 230 180 200 155 210 220 200 240 200 Time to exceed PHR200kW/ ^m2 (sec) 0 0 7 2 5 0 6 5 4 7 6 Maximum average rate of heat dissipation (MARHE) (kW/m ² ) 35 40 80 50 60 40 80 60 50 85 85

[Example 13] Except in Example 12, a second polyurethane emulsion containing 22 mass% of the second polyurethane and 28 mass% of the dialkylphosphinic acid metal salt was used instead of 10 mass% of the second polyurethane emulsion. The second polyurethane was carried out in the same manner except for the second polyurethane emulsion of 28% by mass of dialkylphosphinic acid metal salt to obtain a pile-like artificial leather and evaluated. The results are shown in Table 3.

[Example 14] Except that in Example 12, a fluffy artificial leather with a first polyurethane content of 19% by mass was produced instead of a fluffy artificial leather with a first polyurethane content of 10% by mass. , were carried out in the same manner to obtain vuff-like artificial leather, and evaluated. The results are shown in Table 3.

[Example 15] In addition to Example 12, the second polyurethane emulsion in which particles of a dialkylphosphinic acid metal salt which is a phosphorus-based flame retardant was dispersed was changed to 60 g/m Instead of coating in the manner of ² , instead of applying in the manner of 110 g/m ² , the process was carried out in the same manner to obtain a pile-like artificial leather and evaluated. The results are shown in Table 3.

[Example 16] In Example 12, a nonwoven fabric was formed by three-dimensionally entangling fiber bundles containing 6 ultrafine fibers of 0.4 dtex, instead of entangled fiber bundles containing 25 ultrafine fibers of 0.1 dtex three-dimensionally. Made of non-woven fabric. In addition, the first polyurethane system uses a self-emulsifying polyurethane with a mass ratio of amorphous polycarbonate and polyether polyol of 60/40 and a 100% modulus of 3.0 MPa, instead of containing 4,4'-diphenylmethane diisocyanate is a self-emulsifying amorphous polycarbonate urethane with a 100% modulus of 3.0MPa as the diisocyanate component. In addition, as the phosphorus-based flame retardant particles, the monoalkylphosphinic acid metal salt shown in Table 3 was used instead of the dialkylphosphinic acid metal salt. This process was carried out similarly to the external system, and a pile-like artificial leather was obtained and evaluated. The results are shown in Table 3.

[Example 17] Except that in Example 12, as the phosphorus-based flame retardant particles, the aromatic phosphonate shown in Table 3 was used instead of the dialkylphosphinic acid metal salt, the process was carried out in the same manner to obtain a fluffy artificial leather. Evaluation. The results are shown in Table 3.

[Example 18] In Example 12, except that the phosphate amide shown in Table 3 was used as the phosphorus-based flame retardant particles instead of the dialkylphosphinic acid metal salt, the process was carried out in the same manner to obtain and evaluate the downy artificial leather. . The results are shown in Table 3.

[Example 19] In Example 12, polyethylene and 6-nylon were mixed at a mass ratio of 50/50 and melted, and the molten resin was supplied to a mixing spinneret and discharged from the nozzle hole. The average number of islands is about 600, and by extension, a fiber of 5.5 dtex is obtained. After the fiber was crimped, it was cut into 51mm pieces and carded to obtain a short fiber network with a unit area weight of 100g/ ^m2 . Use a cross-laying device to stack 6 layers to make a mesh. After spraying oil, perform needle punching at 1500 knots/cm ² and then heat press to obtain an apparent density of 0.40g/cm ³ . Fiber entanglement with a thickness of 1.2mm. Then, for the fiber entangled body, the diisocyanate component includes 4,4'-diphenylmethane diisocyanate and the polymer polyol includes a mass ratio of 75/25 polycarbonate polyol and polyester polyol with 100% modulus As the first polyurethane, 5.0 MPa of polyurethane dissolved in N,N-dimethylformamide was impregnated so as to have the mass ratio shown in Table 3, and then immersed in After solidifying the mixture of N,N-dimethylformamide and water, the polyethylene is extracted with toluene and dried. Thereafter, the process was carried out in the same manner as in Example 12, except that the dye was changed from disperse dyeing to gold-containing dyeing, to obtain and evaluate the downy artificial leather. The results are shown in Table 3.

[Example 20]

In Example 19, except that the number of stacked short fiber mesh sheets was changed from 6 sheets to 4 sheets, the same procedure was performed to obtain a thickness of 0.3 mm, a basis weight of 128 g/m ² , and an apparent density of 0.43 g/cm. ^3. Velvety artificial leather for evaluation. The results are shown in Table 3.

[Example 21]

In Example 12, except that a cross-laid device was used to stack 10 layers of mesh so that the total weight per unit area became 330 g/m ² , the same procedure was performed to obtain a thickness of 0.55 mm and a weight per unit area of 300 g/m ² . The fluffy artificial leather with an apparent density of 0.54g/ ^cm3 was evaluated. The results are shown in Table 3.

[Example 22]

Except in Example 12, a cross-laid device was used, 32 layers were stacked instead of 8 layers of mesh, no shrinkage processing was performed, and the content of the first polyurethane was impregnated so that the content rate of the first polyurethane became 12% by mass. Except for the treatment, the same process was carried out to obtain a pile-like artificial leather with a thickness of 1.0 mm, a weight per unit area of 300 g/m ² , and an apparent density of 0.30 g/cm ³ and evaluated. The results are shown in Table 3.

[Comparative example 6] Except in Example 12, a second polyurethane emulsion containing 10 mass% of the second polyurethane and 6.8 mass% of the dialkylphosphinic acid metal salt was used instead of containing 10 mass% of the second polyurethane emulsion. The second polyurethane was carried out in the same manner except for the second polyurethane emulsion of 28% by mass of dialkylphosphinic acid metal salt to obtain a pile-like artificial leather and evaluated. In addition, the viscosity of the aqueous dispersion composed of the phosphorus-based flame retardant particles and the second polymer elastomer was 100 mPa·sec. The results are shown in Table 4.

[Table 4] Comparative example number Comparative example 6 Comparative example 7 Comparative example 8 Comparative example 9 Comparative example 10 Plush artificial leather very fine fiber Fineness (dtex) 0.1 0.1 0.1 0.1 0.6 Resin PET PET PET PET PET No. 1 Polymer Elastomer Content rate (C) (mass %) 11 10 10 10 10 2nd Polymer Elastomer Content rate (D) (mass %) 6 0 5 5 5 Phosphorus flame retardant particles Content rate (E) (mass %) 3.9 15.2 14.4 14.4 8.2 compound Dialkylphosphinic acid metal salt Ammonium polyphosphate Ammonium polyphosphate Aromatic phosphate ester Dialkylphosphinic acid metal salt Dispersed particle size (D ₅₀ : μm) 4 20 20 0.5 4 Water solubility (%: 30℃) >0.2% 0.5 0.5 >0.2% >0.2% Melting point, thermal decomposition temperature when there is no melting point (℃) >250℃ >250℃ >250℃ 115℃ >250℃ Phosphorus atom content (mass %) (F) 23.5 31 31 10 23.5 Content ratio of phosphorus-based flame retardant particles in the total amount of phosphorus-based flame retardant particles and the second polymer elastomer ((E)*(F)/(D+E)) (mass %) 9.3 31.0 23.0 7.4 14.6 Content ratio of phosphorus-based flame retardant particles to the total amount of the first polymer elastomer and the second polymer elastomer ((E)*(F)/(C+D+E) ) (mass%) 4.4 18.7 15.2 4.9 8.3 Phosphorus atom conversion content rate (E)*(F)/100 (mass %) 0.9 4.7 4.5 1.4 1.9 Average particle size of phosphorus flame retardant (SEM: μm) 4 20 20 non-particle 4 Thickness from the back surface where the phosphorus-based flame retardant particles and the second polymer elastomer exist (L: μm) 300 50 50 200 200 Thickness of downy artificial leather (T: mm) 0.4 0.4 0.4 0.4 0.75 Ratio of thickness L to thickness T (%) 75 13 13 50 27 Weight per unit area g/ ^m2 200 210 225 225 390 apparent density g/cm ³ 0.5 0.53 0.56 0.56 0.5 High-end surface B B,D D C A Combustion test (self-extinguishing) Burning distance(mm) 300 140 165 300 260 Self-extinguishing time (seconds) 30 7 9.5 38 twenty four Self-extinguishing time after dripping (seconds) 8 0 2.5 15 8 composite materials adhesive Starch-vinyl acetate resin Starch-vinyl acetate resin Starch-vinyl acetate resin Starch-vinyl acetate resin Starch-vinyl acetate resin Interior base material (back panel) calcium silicate plaster plaster calcium silicate calcium silicate Smoke test Smoke concentration (SPR) 18 8 15 16 16 Combustion heat test Total calorific value (THR: MJ/m ²・20min) 20 9 16 twenty four 18 Maximum heat generation (PHRR: kW/m ² ) 340 200 270 360 300 Time to exceed PHR200kW/ ^m2 (sec) 16 8 14 18 18 Maximum average rate of heat dissipation (MARHE) (kW/m ² ) 160 60 120 180 110

[Comparative Example 7] Except in Example 12, an aqueous dispersion containing 28% by mass of ammonium polyphosphate with a dispersed particle size of 20 μm was used instead of containing 10% by mass of the second polyurethane and 28% by mass of the dialkyl phosphate. Except for the second polyurethane emulsion of the phosphonic acid metal salt, the process was carried out in the same manner to obtain a pile-like artificial leather and evaluated. In addition, the viscosity of the aqueous dispersion composed of the phosphorus-based flame retardant particles and the second polymer elastomer was 100 mPa·sec. The results are shown in Table 4.

[Comparative example 8] Except in Example 12, the first self-emulsifying amorphous polycarbonate urethane with a 100% modulus of 3.0 MPa containing 4,4'-dicyclohexylmethane diisocyanate as the diisocyanate component was used. Polyurethane, changed to the first polyamine of self-emulsifying amorphous polycarbonate urethane whose diisocyanate component contains 1,6-hexamethylene diisocyanate and 100% modulus of 2.0MPa Formate was further evaluated in the same manner except that the ammonium polyphosphate shown in Table 1 was used instead of the dialkylphosphinate metal salt as the phosphorus-based flame retardant particles. The results are shown in Table 4.

[Comparative Example 9] Except that in Example 12, as the phosphorus-based flame retardant particles, the aromatic phosphate ester shown in Table 4 was used instead of the dialkylphosphinic acid metal salt, the process was carried out in the same manner to obtain a fluffy artificial leather and evaluated. The results are shown in Table 4. In addition, although the phosphorus-based flame retardant is treated in the form of an aqueous dispersion during the flame retardant treatment, when observed in the pile-like artificial leather, it is in the form of a resin film rather than in the form of particles.

[Comparative Example 10] In Example 12, the same procedure was performed except that the number of island components of the spinneret was changed from 25 to 4, and the number of overlapping layers of the mesh of the downy artificial leather was changed from 8 to 16. A pile-like artificial leather was obtained and evaluated. The results are shown in Table 4.

Referring to Table 3 and Table 4, the artificial leather base materials obtained in Examples 12 to 22 all have a good surface quality, soft hand feel, and furthermore, good self-extinguishing properties, and low smoke and combustion calorific value. , and has a high level of flame-retardant plush artificial leather. On the other hand, the fluffy artificial leather obtained in Comparative Example 6, in which the phosphorus-based flame retardant particles were few and the flame retardant particles were present in the interior, had the phosphorus-based flame retardant exposed on the surface and had a poor surface quality. Furthermore, the fluffy artificial leather obtained in Comparative Example 7 using ammonium polyphosphate as the phosphorus-based flame retardant particles exuded over time and had a poor appearance. In addition, the downy artificial leather obtained in Comparative Example 8 exuded over time and had a poor appearance. In addition, Comparative Example 9 in which the phosphorus-based flame retardant particles were changed to aromatic phosphate ester had a hard feel. In addition, Comparative Example 10, in which the fineness of the pile-like artificial leather is high and the weight per unit area is also high, is poor in flame retardancy.

without.

without.

without.

Claims (12)

A pile-like artificial leather composed of a fiber entangled body containing ultrafine fibers with a fineness of 0.5 dtex or less, a polymer elastomer impregnated into the fiber entangled body, and phosphorus-based flame retardant particles, and has a The ultra-fine fiber raised pile surface is the main surface of the pile-like artificial leather with a thickness of 0.25~1.5mm, wherein the polymer elastomer includes the first polyurethane present in the entire thickness section, and the first polyurethane present in the thickness section. A second polyurethane with a thickness of 200 μm or less from the back surface relative to the main surface; 90 to 100% by mass of the phosphorus-based flame retardant particles are attached to the second polyurethane, and the The average particle size of the phosphorus flame retardant particles is 0.1~30μm, the phosphorus atom content is more than 14% by mass, the solubility in water at 30°C is less than 0.2% by mass, and the melting point or decomposition temperature when the melting point does not exist is 150°C. As mentioned above, the content ratio of the phosphorus-based flame retardant particles is 1 to 6 mass % in terms of phosphorus atoms. The velvety artificial leather of claim 1, wherein at least one of the first polyurethane and the second polyurethane includes polyurethane, and the polyurethane is composed of a polymeric polyurethane The reaction product of alcohol, organic polyisocyanate, and polyurethane raw materials with chain extender; more than 60% by mass of the polymer polyol is polycarbonate polyol, and the average repeating carbon number after removing the reactive functional groups The number is below 6.5; the organic polyisocyanate contains 4,4'-dicyclohexylmethane. At least one kind from the group consisting of diisocyanate and 4,4’-diphenylmethane diisocyanate. For example, the weight per unit area of the velvety artificial leather in claim 1 is 100~300g/m ² . The velvety artificial leather of claim 1, wherein the phosphorus-based flame retardant particles include at least one compound selected from the group consisting of organic phosphinic acid metal salts, aromatic phosphonic acid esters and phosphoric acid ester amide. The velvety artificial leather of claim 1, wherein the phosphorus-based flame retardant particles include at least one selected from the group consisting of dialkylphosphinic acid metal salts and monoalkylphosphinic acid metal salts. For example, in the velvety artificial leather of claim 1, the thickness of the area where the phosphorus flame retardant particles tend to exist is 10 to 60% relative to the total thickness. For example, the velvety artificial leather of claim 1, wherein the content ratio of the phosphorus flame retardant particles in the total amount of the phosphorus flame retardant particles and the polymer elastomer is 5 to 20 mass % in terms of phosphorus atoms. Such as the pile-like artificial leather of claim 1, wherein the content ratio of the phosphorus flame retardant particles in the total amount of the phosphorus flame retardant particles and the second polyurethane is 10 to 30 in terms of phosphorus atoms. Mass %. A composite material, which is formed by adhering an interior base material to the back of the velvety artificial leather according to any one of claims 1 to 8 using an adhesive. For example, the composite material of claim 9 has a total heating value (THR) of less than 10MJ/ ^m2 . For example, the composite material of claim 9 has a maximum heat generation rate (PHRR) of less than 250kW/ ^m2 . For example, the composite material of claim 9 has a maximum average rate of heat dissipation (MARHE) of less than 90kW/ ^m2 .