WO2025204893A1 - Composite body, vehicle interior material including same, vehicle component, seat - Google Patents

Abstract

The present invention addresses the problem of providing a sheet that has favorable surface quality and texture as well as favorable strength and flame-retardance performance without being susceptible to seam spotting. The present invention relates to a composite body that is formed by adjacently layering an artificial leather and a woven or knitted article a. The artificial leather includes: a fiber structure that includes a base material composed of ultrafine fibers as a constituent element; and a polymer elastic body. The woven or knitted article a includes modacrylic fibers. An adhesive resin is present in spots between the artificial leather and the woven or knitted fabric a.

Description

Composites and vehicle interior materials, vehicle parts, and seats containing the composites

The present invention relates to a composite in which artificial leather and a woven or knitted fabric are layered adjacent to each other.

Artificial leather, which primarily contains a fiber structure containing ultrafine fibers and a polymer elastomer, is more durable than natural leather and can be made to a consistent quality, making it used in a variety of fields, including vehicle interiors, interior goods, shoes, and clothing. When this artificial leather is used for vehicle seats, furniture, etc., it is required to have good surface quality and texture, as well as strength and flame retardancy.

Various proposals have been made to impart strength and flame retardancy to artificial leather. For example, Patent Document 1 proposes a flame-retardant artificial leather characterized by the addition of a flame-retardant resin composition containing ammonium polyphosphate that has been treated to make it difficult to dissolve in water, a triazine-based flame retardant with a specific range of water solubility, and a binder resin to an artificial leather comprising a thermoplastic synthetic fiber fabric made from woven, knitted, or nonwoven fabric and a polymeric elastomer impregnated therein. Patent Document 1 also discloses that the manufacturing method described in Patent Document 1 makes it possible to provide flame-retardant artificial leather that has excellent flame retardancy without impairing the inherent softness of the artificial leather, and that also has excellent flame resistance by suppressing the occurrence of scratches (described below), and that exhibits excellent heat resistance by suppressing discoloration of the resin composition even when exposed to high temperatures.

Furthermore, Patent Document 2 proposes a flame-retardant leather-like sheet substrate comprising a nonwoven fabric in which ultrafine fibers are three-dimensionally entangled and a polymeric elastomer, in which at least a portion of the ultrafine fibers are made of an organic phosphorus component copolymerized polyester, and the polymeric elastomer is made of a polycarbonate-based polyurethane copolymerized with an organic phosphorus component. It also describes that this configuration results in a halogen-free sheet that is highly flame-retardant, and also has extremely excellent durability of the flame-retardant properties.

Furthermore, Patent Document 3 proposes artificial leather with an apparent density within a specific range, which is made up of a nonwoven fabric in which a blend of fibers primarily consisting of polyester shrinkable fiber, latent crimp fiber, and meta-aramid fiber is entangled, with the shrinkage and crimp of each fiber being manifested, and which is characterized by the content of each fiber being specific. It is stated that this composition results in significantly improved texture and flame retardancy compared to conventional artificial leathers with a similar apparent density.

JP 2013-227685 A Japanese Patent Application Laid-Open No. 2002-201574 Japanese Patent Application Laid-Open No. 2008-133578

A known technique for imparting flame retardancy to artificial leather is to apply a water-soluble flame retardant such as guanidine phosphate to the entire surface of the artificial leather. However, this method has problems such as the loss of the smooth, raised feel of the raised nap on the surface of the artificial leather, and when the artificial leather absorbs moisture and dries, the moisture causes the guanidine phosphate to dissolve and migrate to the surface, forming ring-shaped stains known as "edge marks," which significantly impair the design of the artificial leather.

The technology proposed in Patent Document 1 makes it possible to obtain artificial leather that is less harsh and has a certain level of flame retardancy while maintaining a smooth surface. However, because a flame-retardant resin composition containing a binder resin is added, there is room for improvement in the texture and drape of the artificial leather.

On the other hand, in the technology proposed in Patent Document 2, the polymer elastomer, which is an important constituent substance for imparting strength and texture to artificial leather, is polyurethane copolymerized with an organic phosphorus component, so the design results in reduced texture and durability compared to ordinary polymer elastomers.

Furthermore, the technology proposed in Patent Document 3 involves blending multiple types of fibers, such as polyester fibers and meta-aramid fibers, in the artificial leather fiber structure, making it difficult to achieve uniform nap raising and dyeing, resulting in uneven surface quality.

The present invention was made in light of the above circumstances, and its purpose is to provide a sheet that is smooth, has good surface quality and texture, and is strong and flame-retardant.

As a result of extensive research conducted by the inventors to achieve the above objective, they discovered that by laminating artificial leather with a woven or knitted fabric containing specific flame-retardant fibers to form a composite, and by having an adhesive resin present in a dispersed state between the layers of the artificial leather and the woven or knitted fabric, a composite can be obtained that not only has good surface quality and texture, but also strength and flame retardancy.

The present invention was completed based on these findings, and provides the following inventions:

[1] A composite in which an artificial leather and a woven or knitted fabric a are laminated adjacent to each other,
The artificial leather is
A fiber structure including, as a component, a substrate made of ultrafine fibers;
A polymeric elastomer;
Including,
The woven or knitted fabric a contains modacrylic fibers,
An adhesive resin is dispersed between the layers of the artificial leather and the woven or knitted fabric a.
Complex.

[2] The composite described in [1] above, wherein the polyester fiber content in the woven or knitted fabric a is 5% by mass or more and 50% by mass or less.

[3] The composite described in [1] or [2] above, wherein the modacrylic fiber content in the composite is 20% by mass or more and 50% by mass or less.

[4] The composite described in any one of [1] to [3] above, wherein the fiber structure further comprises a woven or knitted fabric b.

[5] A vehicle interior material comprising the composite described in any one of [1] to [4].

[6] A vehicle part comprising the composite described in any one of [1] to [4].

[7] A seat comprising the composite described in any one of [1] to [4].

The present invention makes it possible to obtain composites that are smooth, have good surface quality and texture, and also have excellent strength and flame retardancy.

FIG. 1 is a cross-sectional view of an artificial leather for illustrating and explaining the method for measuring and calculating the nap length of the composite artificial leather of the present invention. FIG. 2 is a perspective conceptual diagram illustrating and explaining one embodiment of the adhesive resin in the composite of the present invention (in a state where it is arranged in a dot pattern). FIG. 3 is a perspective conceptual diagram illustrating and explaining one embodiment of the adhesive resin in the composite of the present invention (in a state where it is arranged in a lattice pattern). FIG. 4 is a perspective conceptual diagram illustrating and explaining one embodiment of the adhesive resin in the composite of the present invention (in a state where it is arranged in stripes). FIG. 5 is a perspective conceptual diagram illustrating and explaining one embodiment of the adhesive resin in the composite of the present invention (in a state where the adhesive resin is arranged in a random network pattern). FIG. 6 is a perspective conceptual diagram illustrating and explaining the form of the adhesive resin (in which the adhesive resin is present substantially over the entire surface) of the present invention, which is not a composite. FIG. 7 is a perspective conceptual diagram illustrating and explaining the form of the adhesive resin (disposed only at the end of the woven or knitted fabric a) of the present invention, which is not a composite. FIG. 8 is a perspective conceptual diagram illustrating and explaining the form of the adhesive resin of the present invention that is not a composite (a state in which the adhesive resin is locally disposed only in a part of the woven or knitted fabric a).

The composite of the present invention is a composite formed by adjacently laminating artificial leather and woven/knitted fabric a, wherein the artificial leather comprises a fiber structure containing as a component a substrate made of ultrafine fibers, and a polymeric elastomer, the woven/knitted fabric a comprises modacrylic fibers, and an adhesive resin is present in a dispersed state between the layers of the artificial leather and the woven/knitted fabric. These components are described in detail below, but the present invention is not limited to the scope described below as long as it does not deviate from the gist of the invention, and various modifications are possible within the scope of the invention.

In the present invention, woven and knitted fabrics is a general term for woven and knitted fabrics.

[Substrate composed of ultrafine fibers]
First, the artificial leather according to the composite of the present invention includes a fiber structure, and the fiber structure includes a substrate made of ultrafine fibers as a constituent element.

These ultrafine fibers are preferably made of a thermoplastic resin. Any resin capable of forming a fiber can be used as the thermoplastic resin, including polyester-based resins such as "polyethylene terephthalate, polybutylene terephthalate, and polyester elastomers," polyamide-based resins such as "polyamide 6, polyamide 66, and polyamide elastomers," polyurethane-based resins, polyolefin-based resins, and acrylonitrile-based resins. However, polyester-based resins are preferred from the standpoint of durability, particularly mechanical strength and heat resistance. In this invention, "polyester-based resin" refers to a resin in which the molar fraction of the polyester unit in the repeating units is 80 mol% to 100 mol%. Unless otherwise specified, the same applies when referring to "based resin."

Examples of the polyester resin include polyethylene terephthalate, polytrimethylene terephthalate, polytetramethylene terephthalate, polycyclohexylene dimethylene terephthalate, polyethylene-2,6-naphthalenedicarboxylate, and polyethylene-1,2-bis(2-chlorophenoxy)ethane-4,4'-dicarboxylate. Among these, polyethylene terephthalate, which is the most commonly used, or a polyester copolymer containing primarily ethylene terephthalate units is preferably used.

If necessary, inorganic particles such as titanium oxide particles, lubricants, heat stabilizers, UV absorbers, conductive agents, heat storage agents, antibacterial agents, etc. can be added to the above-mentioned thermoplastic resin, as long as the purpose of the present invention is not impaired. In particular, when producing artificial leather with a deep color, it is preferable for the thermoplastic resin that makes up the ultrafine fibers to contain a black pigment such as carbon black and/or a chromatic pigment such as nickel titanium yellow.

In addition, in the present invention, ultrafine fibers refer to fibers with a single fiber diameter of 15.0 μm or less, and it is preferable that the average single fiber diameter of these ultrafine fibers be 0.1 μm or more and 10.0 μm or less. By setting the average single fiber diameter of the ultrafine fibers to a range of preferably 0.1 μm or more, and more preferably 0.5 μm or more, a composite with excellent color development after dyeing, light fastness, and friction fastness, as well as stability during spinning, is obtained. On the other hand, by setting the range to preferably 10.0 μm or less, and more preferably 8.0 μm or less, a composite with excellent surface quality that is dense and soft to the touch is obtained.

In the present invention, the average single fiber diameter of the ultrafine fibers is a value measured and calculated by the following method.
(i) A scanning electron microscope (SEM, for example, Keyence Corporation's "VHX-D500/D510") photograph is taken of the cross section of the artificial leather from the cross section of the composite, and 10 fibers that are considered to be circular or nearly circular, oval, ultrafine fibers (fibers that appear to be 15.0 μm or less) are randomly selected and their single fiber diameter is measured. However, if the measured single fiber diameter exceeds 15.0 μm, that fiber is not an ultrafine fiber, and another ultrafine fiber is selected and its single fiber diameter is measured.
(ii) Calculate the arithmetic mean value of the diameters of the 10 single fibers and round off to the nearest tenth.

The cross-sectional shape of the ultrafine fibers of the present invention is preferably round, as this facilitates stable formation of ultrafine fibers for artificial leather during the composite manufacturing stage and results in a composite with an excellent balance of quality, texture, and strength. However, cross-sectional shapes such as oval, polygonal (flat, triangular, etc.), fan, cross, hollow, Y-shaped, T-shaped, and U-shaped irregular cross-sections can also be used as appropriate to suit the properties desired for the composite. In this case, the average single fiber diameter of the above-mentioned ultrafine fibers is determined by first measuring the cross-sectional area of a single fiber and then calculating the diameter when the cross section is considered to be circular.

The substrate of the present invention is composed of the ultrafine fibers described above. Such substrates may take the form of nonwoven fabrics, woven or knitted fabrics, or fabrics containing both, and can be selected appropriately depending on the cost and properties required for each application or purpose.

Among these, it is preferable that the substrate is a nonwoven fabric. Using such a substrate will result in a composite with excellent quality, due to its rich texture and fine nap, when the artificial leather has a raised surface.

When the substrate is a nonwoven fabric, the nonwoven fabric may take the form of a long-fiber nonwoven fabric composed primarily of filaments, or a short-fiber nonwoven fabric composed primarily of fibers of 100 mm or less. Long-fiber nonwoven fabrics are preferred because they result in composites with excellent strength. On the other hand, short-fiber nonwoven fabrics allow for more fibers to be oriented in the thickness direction of the artificial leather than long-fiber nonwoven fabrics, and when the surface of the artificial leather is raised, they result in composites with a highly dense surface.

When using a short-fiber nonwoven fabric, the fiber length of the ultrafine fibers is preferably 25 mm or more and 90 mm or less. By setting the upper limit of the fiber length range to preferably 90 mm or less, more preferably 80 mm or less, and even more preferably 70 mm or less, a composite with good quality and texture will be obtained. On the other hand, by setting the lower limit of the fiber length range to preferably 25 mm or more, more preferably 35 mm or more, and even more preferably 40 mm or more, a composite with excellent abrasion resistance will be obtained.

It is also preferable to include a woven or knitted fabric made from the above-mentioned ultrafine fibers as a component. Such a fiber structure allows for a composite with excellent uniformity in thickness and quality.

[Fiber structure]
The fiber structure according to the present invention includes, as a constituent element, a substrate made of the ultrafine fibers.

Furthermore, it is also preferable that the fiber structure further includes a woven or knitted fabric b. Specifically, the woven or knitted fabric b is laminated inside the substrate or on one surface. In particular, when the composite has openings, it is preferable that the woven or knitted fabric b is a woven fabric, as this results in a composite that can ensure strength. Note that "the composite has openings" refers to the presence of portions with holes (through openings) that penetrate the composite in the thickness direction. This woven or knitted fabric b is different from the woven or knitted fabric a described below, and is composed primarily of fibers other than modacrylic fibers. Here, "woven or knitted fabrics composed primarily of fibers other than modacrylic fibers" refers to woven or knitted fabrics (including those that do not contain modacrylic fibers) in which the modacrylic fiber content of the fibers that make up the woven or knitted fabric is 1.0 mass% or less.

Fibers that make up the woven or knitted fabric (b) are preferably filament yarns, spun yarns, or composite yarns made from filament yarns and spun yarns, and from the standpoint of durability, particularly mechanical strength, it is more preferable to use multifilaments made from polyester resins or polyamide resins.

The average single fiber diameter of the fibers constituting the woven/knitted fabric b is preferably 1 μm or more and 50 μm or less. By setting the upper limit of this range of average single fiber diameter to preferably 50 μm or less, more preferably 15 μm or less, and even more preferably 13 μm or less, a composite with excellent flexibility is obtained. Furthermore, even if the fibers of woven/knitted fabric b are exposed on the surface of the composite, the hue difference with the pigment-containing ultrafine fibers after dyeing is small, resulting in a composite without impairing the uniformity of the surface hue. On the other hand, by setting the lower limit of the range of average single fiber diameter of the fibers constituting the woven/knitted fabric b to 1 μm or more, more preferably 8 μm or more, and even more preferably 9 μm or more, a composite with high dimensional stability is obtained.

In the present invention, the average single fiber diameter of the fibers constituting the woven or knitted fabric b is a value measured and calculated by taking a scanning electron microscope (SEM, for example, Keyence Corporation's "VHX-D500/D510") photograph of the cross section of the composite, randomly selecting 10 fibers constituting the woven or knitted fabric b, measuring the single fiber diameter of those fibers, calculating the arithmetic average of the 10 fibers, and rounding off to one decimal place.

If the fibers constituting the woven/knitted fabric b are multifilaments, the total fineness of the multifilaments is preferably 30 dtex or more and 170 dtex or less. A composite with excellent flexibility can be obtained by setting the upper limit of the total fineness range of the yarns constituting the woven/knitted fabric b to 170 dtex or less. On the other hand, a lower limit of the total fineness range of the yarns constituting the woven/knitted fabric b to 30 dtex or more is preferred, as this not only improves the dimensional stability of the composite product, but also makes it less likely that the fibers constituting the woven/knitted fabric b will be exposed on the surface of the composite when the nonwoven fabric and the woven/knitted fabric b are entangled and integrated by needle punching or the like. In this case, it is preferable that the total fineness of the multifilaments of the warp and weft yarns be the same.

The total fineness of the yarns making up the above woven or knitted fabric b refers to the value measured and calculated according to "8.3 Fineness" of "8.3.1 Correct fineness b) Method B (simplified method)" in "8.3 Fineness" of JIS L1013:2010 "Testing methods for chemical fiber filament yarns."

In this case, the fiber structure of the present invention is preferably formed by entangling the substrate and woven/knitted fabric b together. Such a fiber structure results in a composite with excellent strength and shape stability, particularly when the composite has openings. In the present invention, "the substrate and woven/knitted fabric b are entangled together" refers to a state in which there are multiple areas where the ultrafine fibers that make up the substrate and the fibers that make up woven/knitted fabric b are entangled, and the substrate and woven/knitted fabric b are integrated.

[Polymeric elastomer]
The artificial leather of the composite of the present invention contains an elastomer. Here, in the present invention, "containing an elastomer" refers to a state in which the elastomer is contained in the central 40% of the artificial leather in the composite, excluding the 30% of the thickness direction from both surfaces excluding the napped portions, and this can be determined by the following procedures (1) to (7).
(1) With the napped surface of the artificial leather laid down using a lint brush or the like, a thin slice 1 mm thick is prepared in the thickness direction of the artificial leather from a randomly selected position within the artificial leather.
(2) Using a scanning electron microscope (SEM, for example, Keyence Corporation's "VHX-D500/D510 type"), observe the cross section of the thin section of (1), excluding 30% of the area in the thickness direction from both surfaces, and the remaining central 40%.
(3) In the SEM image, the presence or absence of substances other than the fibers that make up the fiber structure is confirmed.
(4) If there are any substances other than the fibers that make up the fiber structure, remove them by peeling off the substances applied to the surface layer of the artificial leather.
(5) Remove 30% of the thickness of both surfaces of the artificial leather, excluding the napped portions, by polishing or the like, leaving only the central 40%.
(6) The test piece (5) is dissolved in N,N-dimethylformamide (DMF) and hexafluoro-2-propanol (HFIP), and the presence or absence of the elastomer is confirmed by analyzing the composition of the solute in the DMF solution and the insoluble matter in the HFIP. In the composition analysis, the presence or absence of the elastomer is confirmed by, for example, infrared spectroscopy (IR).
(7) When the structure of a polymeric elastomer described below can be confirmed in either the solute in the DMF solution or the insoluble matter in HFIP, it is considered to contain a polymeric elastomer.

This polymeric elastomer acts as a binder that holds the ultrafine fibers that make up the artificial leather, so in consideration of the soft feel of the composite of the present invention, it is preferable to use polyurethane as the main component of the polymeric elastomer used. Note that, in this invention, "main component" means that the mass of polyurethane is greater than 50% by mass of the total mass of the polymeric elastomer.

In the present invention, the polyurethane preferably used as the polymeric elastomer can be either an organic solvent-based polyurethane, which is used in a dissolved state in an organic solvent, or a water-dispersed polyurethane, which is used in a dispersed state in water. Here, in the present invention, water-dispersed polyurethane refers to a polyurethane that has a hydrophilic group and a solubility in DMF of less than 40 g/100 g-DMF (less than 40 g of the polyurethane can be dissolved in 100 g of DMF). Conversely, a polyurethane that has a solubility in DMF of 40 g/100 g-DMF or more (40 g or more of the polyurethane can be dissolved in 100 g of DMF) is considered to be an organic solvent-based polyurethane resin.

In the present invention, polyurethane, which is preferably used as the polymeric elastomer, can be used in combination with a crosslinking agent to improve water resistance, abrasion resistance, hydrolysis resistance, etc. The crosslinking agent can be an external crosslinking agent added to polyurethane as a third component, or an internal crosslinking agent that pre-introduces reactive points that form crosslinked structures within the polyurethane's molecular structure. Internal crosslinking agents are more preferred from the perspective of reducing loss of flexibility, as they can form uniform crosslinking points within the polyurethane's molecular structure.

In addition, the polymer elastomer can contain various additives depending on the purpose, such as flame retardants such as "phosphorus-based, halogen-based, and inorganic" antioxidants, "phenol-based, sulfur-based, and phosphorus-based" antioxidants, ultraviolet absorbers such as "benzotriazole-based, triazine-based, benzophenone-based, salicylate-based, cyanoacrylate-based, and oxalic acid anilide-based" ultraviolet absorbers, light stabilizers such as "hindered amine-based and benzoate-based" stabilizers, hydrolysis-resistant stabilizers such as "carbodiimide-based and oxazoline-based" stabilizers, plasticizers, antistatic agents, surfactants, coagulation adjusters, carbon black, and dyes.

Generally, the content of polymer elastomer in artificial leather can be adjusted as appropriate, taking into consideration the type of polymer elastomer used, the manufacturing method of the polymer elastomer, and the texture and physical properties. However, in the present invention, the content of polymer elastomer is preferably 2% by mass or more and 50% by mass or less, based on the mass of the artificial leather. By setting the lower limit of the polymer elastomer content range to preferably 2% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more, the bonds between the fibers by the polymer elastomer can be strengthened during the artificial leather production stage, resulting in a strong and excellent composite. On the other hand, by setting the upper limit of the polymer elastomer content range to preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less, not only will the composite have a soft texture, but it will also be able to suppress dye staining of other fabrics washed at the same time.

In the present invention, the content (mass %) of the polymeric elastomer in the artificial leather is a value measured and calculated by the following procedure.
(1) Three test pieces measuring 10 cm x 10 cm are randomly taken from the composite.
(2) If there is a substance applied to the surface layer of the artificial leather in the composite, remove that layer by peeling it off or the like.
(3) Remove 30% of the thickness of both surfaces of the artificial leather, excluding the napped portion, by polishing or the like, leaving only the central 40%.
(4) In the method (7) for confirming whether or not the polymeric elastomer is contained, if the structure of the polymeric elastomer is confirmed on the solute side in the DMF solution, the procedure (5) is carried out, and if the structure of the polymeric elastomer is confirmed on the insoluble side in HFIP, the procedure (6) is carried out to calculate the content of the polymeric elastomer. If the structure of the polymeric elastomer is confirmed in both DMF and HFIP, the larger of the values calculated in the procedures (5) and (6) is adopted as the content of the polymeric elastomer.
(5) The test piece is immersed in DMF and dried at 25° C. for 24 hours. The mass ratio of the test piece before and after dissolution is calculated using the following formula, and the arithmetic mean value (%) of the three test pieces is rounded to one decimal place to calculate the polymer elastomer content: (sample mass (g) before dissolution - sample mass (g) after dissolution and drying) / (sample mass (g) before dissolution) × 100 (formula).
(6) The test piece is immersed in HFIP and dried for 24 hours at 25° C. The mass ratio of the test piece before and after dissolution is calculated using the following formula, and the arithmetic mean value (%) of the three test pieces is rounded to one decimal place to calculate the polymer elastomer content: (sample mass (g) after dissolution)/(sample mass (g) before dissolution)×100 (formula).

[Artificial leather]
The artificial leather according to the composite of the present invention includes the fiber structure and the elastomer. The artificial leather according to the composite of the present invention preferably has nap on the surface not adjacent to the woven or knitted fabric a, and further preferably has a surface resin layer on the napped surface.

In other words, in the present invention, the raised nap may be present only on the surface of the artificial leather that is not adjacent to the woven or knitted fabric a, as described above, or it is acceptable for the raised nap to be present on both surfaces. From the perspective of design effect, when the raised nap is present on the surface that is not adjacent to the woven or knitted fabric a, it is preferable that the raised nap has a length and directional flexibility that is such that when the user runs a finger over it, the direction of the raised nap changes, leaving a mark, a so-called finger mark.

More specifically, the surface nap length is preferably 200 μm or more and 500 μm or less. By setting the lower limit of this nap length range to preferably 200 μm or more, and more preferably 250 μm or more, the surface nap covers the polymeric elastomer inside the substrate and suppresses exposure of the polymeric elastomer on the surface of the artificial leather that is not adjacent to woven or knitted fabric a, resulting in a composite with uniform color development. Furthermore, when woven or knitted fabric b is entangled and integrated with the nonwoven fabric that constitutes the artificial leather, setting the surface nap length within the above range is preferable because it can adequately cover the fibers of woven or knitted fabric b near the surface of the artificial leather. On the other hand, by setting the upper limit of the nap length range to preferably 500 μm or less, and more preferably 450 μm or less, a composite with excellent design effects and abrasion resistance will be obtained.

In the present invention, the nap length of the artificial leather is measured and calculated by the following method.
(1) For a surface having nap, the nap is raised using a lint brush or the like.
(2) With the nap standing up, two images of the cross section of the artificial leather are taken at 120x magnification using a scanning electron microscope (SEM: for example, Keyence Corporation's "VHX-D500/D510 type").
(3) As shown in FIG. 1, the layer of the cross section consisting only of fibers oriented in the thickness direction is defined as the napped portion (2), and the length from the intersection of the fibers oriented in the thickness direction and the fibers oriented in the surface direction of the artificial leather to the tip of the nap is defined as the nap length (μm), and this is measured at 10 points.
(4) Repeat step (3) for all cross sections, calculate the arithmetic mean value of the above-mentioned nap length (μm), and round off to the first decimal place.

In the present invention, when the surface resin layer is present, the surface resin layer may be a continuous layer (in which case the surface of the composite will have a grain finish) or a discontinuous layer (in which case the surface of the composite will have a semi-grain finish).

This surface resin layer is preferably made of a resin containing one or more selected from the group consisting of styrene butadiene rubber, nitrile rubber, acrylic resin, epoxy resin, polyurethane resin, and natural resin. Among these, polyurethane resin is preferred from the standpoint of flexibility and abrasion resistance.

In the present invention, the resin used in the surface resin layer can contain elastomer resins such as polyesters, polyamides, and polyolefins, acrylic resins, and ethylene-vinyl acetate resins, to the extent that the effects of the present invention are not impaired. These resins can also contain various additives, such as pigments such as carbon black, phosphorus-, halogen-, and inorganic flame retardants, phenol-, sulfur-, and phosphorus-based antioxidants, hindered amine- and benzoate-based light stabilizers, hydrolysis-resistant stabilizers such as polycarbodiimides, plasticizers, antistatic agents, surfactants, coagulation adjusters, and dyes.

[Woven and knitted fabric a]
The woven or knitted fabric (a) of the composite of the present invention contains modacrylic fiber. This modacrylic fiber refers to a fiber containing acrylonitrile, with an acrylonitrile content of 35% by mass or more and less than 85% by mass. The modacrylic fiber generates an inert gas upon combustion, thereby helping to self-extinguish the flame on the surface of the composite. The composite, which includes the woven or knitted fabric (a) containing modacrylic fiber and an artificial leather laminated adjacent to the woven or knitted fabric (a), has voids between the fibers, making the artificial leather, which is structurally prone to combustibility, less flammable.

Furthermore, it is preferable that the woven or knitted fabric a further contains polyester fiber, and the content of the polyester fiber is preferably 5% by mass or more and 50% by mass or less. With the lower limit of the polyester fiber content being preferably 5% by mass or more, and more preferably 10% by mass or more, a composite with excellent strength will be obtained. On the other hand, with the upper limit of the polyester fiber content being preferably 50% by mass or less, and more preferably 45% by mass or less, a composite with excellent flame retardancy will be obtained.

The content ratio of modacrylic fiber or polyester fiber in this woven/knitted fabric a is determined by removing everything other than woven/knitted fabric a from the composite by peeling or polishing, and measuring and calculating the remaining woven/knitted fabric a in accordance with "Part 1: Fiber identification" of JIS L1030-1:2012 "Testing methods for blending ratio in textile products," and "5. Dissolving method" or "6. Dissolution method" of "Part 2: Fiber blending ratio" of JIS L1030-2:2012 "Testing methods for blending ratio in textile products."

Examples of woven or knitted fabrics a in the composite of the present invention include plain weave, twill weave, satin weave, and various woven fabrics based on these weave structures, as well as warp knitting, weft knitting such as tricot knitting, lace knitting, and various knitted fabrics based on these knitting structures. It is also acceptable to use either woven or knitted fabrics.

In particular, when considering the adhesive strength with the artificial leather, the material strength of the woven/knitted fabric a, and the flexibility and flame retardancy of the composite, it is preferable that the woven/knitted fabric a be a woven fabric. This results in a composite with excellent adhesive strength between the artificial leather and the woven/knitted fabric a, as well as excellent flexibility and flame retardancy.

[Complex]
The composite of the present invention is formed by adjacently laminating an artificial leather and a woven or knitted fabric a. An adhesive resin is present in a dispersed state between the layers of the artificial leather and the woven or knitted fabric a. Here, "an adhesive resin is present in a dispersed state between the layers of the artificial leather and the woven or knitted fabric a" specifically means that
The adhesive resin is arranged in a dot pattern as shown in Figure 2.
The adhesive resin is arranged in a grid pattern as shown in FIG.
The adhesive resin is arranged in stripes as shown in FIG.
The adhesive resin is arranged in a random mesh pattern as shown in Figure 5.
And so on,
As shown in Figure 6, the adhesive resin is present on the entire surface.
As shown in FIG. 7, the state in which the woven/knitted fabric a is disposed only at the end portion thereof.
As shown in FIG. 8, the state in which the woven/knitted fabric a is locally arranged only in a part thereof,
It is not like that.

The adhesive resin of the present invention can be selected appropriately from, for example, polyurethane, acrylic resin, silicone resin, polyolefin, polyamide, epoxy resin, vinyl chloride, polyester, etc., depending on the material and form of the woven or knitted fabric (a). Among these, polyurethane or acrylic resin is preferable, taking into consideration flexibility and adhesive strength at high temperatures. Polyurethane, which provides high adhesive strength and flexibility, is particularly preferable. Note that this polyurethane is preferably a moisture-curing reactive hot melt adhesive, or a two-component type mixed with isocyanate and a chain extender.

The modacrylic fiber content in the composite is preferably 20% by mass or more and 50% by mass or less. A lower limit of the modacrylic fiber content of preferably 20% by mass or more, more preferably 25% by mass or more, results in a composite with excellent flame retardancy. On the other hand, an upper limit of the modacrylic fiber content of preferably 50% by mass or less, more preferably 45% by mass or less, results in a composite with excellent strength.

In the present invention, the modacrylic fiber content in the composite is the value measured and calculated in accordance with "Part 1: Fiber identification" of JIS L1030-1:2012 "Testing methods for blending ratios in textile products" and "5. Dissolution method" or "6. Dissolution method" of "Part 2: Fiber blending ratio" of JIS L1030-2:2012 "Testing methods for blending ratios in textile products."

The composite according to the present invention preferably has a basis weight of 200 g/ ^m2 or more and 900 g/ ^m2 or less. With regard to the range of basis weight of the composite, if the lower limit is preferably 200 g/ ^m2 or more, more preferably 250 g/ ^m2 or more, and even more preferably 300 g/ ^m2 or more, the composite will have a solid feel and excellent texture. On the other hand, with regard to the range of basis weight of the composite, if the upper limit is preferably 900 g/m2 or ^less , more preferably 800 g/m2 or ^less , and even more preferably 700 g/m2 or ^less , the composite will have excellent moldability and flexibility.

In the present invention, the basis weight of the composite is a value measured and calculated by the following method.
(i) Three test pieces measuring 5 cm x 5 cm are randomly taken from the composite.
(ii) Measure the mass of the complex to one decimal place.
(iii) The mass of the composite is divided by the area of the test piece to calculate the basis weight of each composite sample. The arithmetic mean value (g/m ² ) of the three test pieces is rounded off to the nearest whole number.

The composite of the present invention preferably has a thickness of 0.2 mm or more and 5.0 mm or less, as measured by "6.1.1 Method A" of "6.1 Thickness (ISO Method)" in JIS L1913:2010 "Testing Methods for General Nonwoven Fabrics." With the lower limit of the composite thickness range being preferably 0.2 mm or more, more preferably 0.3 mm or more, and even more preferably 0.4 mm or more, the composite will not only have excellent processability during manufacturing, but will also have a solid feel and excellent texture. On the other hand, with the upper limit of the composite thickness range being preferably 5.0 mm or less, more preferably 4.5 mm or less, and even more preferably 4.0 mm or less, the composite will have excellent moldability and flexibility.

In the present invention, the thickness of the composite is a value measured and calculated by the following method.
(i) Ten test pieces measuring 2500 ^mm2 or more (for example, 50 mm x 50 mm square test pieces or 60 mm diameter circular test pieces) are taken from the composite.
(ii) A pressure of 0.5 kPa is applied to the upper circular horizontal plate of a thickness measuring instrument (for example, "Dial Thickness Gauge H-1A" manufactured by Ozaki Seisakusho) to adjust the zero point.
(iii) Using a thickness gauge, apply a pressure of 0.5 kPa to the test piece for 10 seconds and measure the thickness to the nearest 0.01 mm.
(iv) The arithmetic mean value (mm) of 10 test pieces is calculated and rounded off to two decimal places.

The composite of the present invention preferably has an average tensile strength of 100 N/5 cm or more and 2000 N/5 cm in any two perpendicular directions, as measured according to "6.3.1 Tensile Strength and Elongation (ISO Method)" of JIS L1913:2010 "Test Methods for General Nonwoven Fabrics." An average tensile strength of 100 N/5 cm or more, more preferably 150 N/5 cm or more, and even more preferably 200 N/5 cm or more, is preferred as this will result in excellent shape stability and durability of the composite. Furthermore, an average tensile strength of 2000 N/5 cm or less, more preferably 1800 N/5 cm or less, and even more preferably 1500 N/5 cm or less will result in a composite with excellent moldability.

The tensile strength can be adjusted by the basis weight and density of the artificial leather, the density of the laminated woven/knitted fabric A and the inserted woven/knitted fabric B, and the total fineness of the constituent yarns.

The composite of the present invention is characterized by excellent flame retardancy, and is preferably a composite that passes the flame retardancy evaluation described below.

The flame retardancy of this composite was evaluated based on the flammability test standard (horizontal burning rate) for automotive interior materials of the Federal Motor Vehicle Safety Standards (FMVSS) No. 302, in which a test specimen (350 mm x 100 mm) was held horizontally and exposed to a 38 mm flame for 15 seconds, and the burning rate for 254 mm between the A and B marks was evaluated according to the following criteria.
- If the fire self-extinguishes before reaching the A mark, it will be classified as "non-flammable" and will pass the test.
If the flame goes beyond the A mark and goes out by itself, the burning distance is within 50 mm, and the burning time is within 60 seconds, the classification is "self-extinguishing" and the flame is deemed to have passed.
If the lamp does not self-extinguish but the burning rate between the marked lines is 80 mm/min or less, the rating category is "burning at or below the specified rate" and the lamp is deemed to have passed.
If the lamp does not self-extinguish and the burning speed between the marked lines exceeds 80 mm/min, the rating category will be "burning faster than the specified speed" and the lamp will be deemed unacceptable.

Furthermore, the flame retardant performance can be adjusted by the proportion of modacrylic fiber in woven/knitted fabric (a) and the basis weight of the artificial leather and woven/knitted fabric (a).

When the composite of the present invention is used as an interior material for a vehicle, it is required to have high breathability, particularly to accommodate seat ventilation systems, and therefore it is also preferable that it have multiple openings.

In the present invention, "opening" is not limited to a hole (through opening) that penetrates the composite in the thickness direction, but also includes, for example, a case where the openings in the artificial leather and woven/knitted fabric a do not overlap in the planar position and do not form a through opening. An example of the latter is a form in which an opening is formed in advance in the artificial leather and then laminated with the woven/knitted fabric a.

The openings can be any shape depending on the desired design, and can be round, oval, polygonal (flat, triangular, etc.), sectoral, cross, hollow, Y-shaped, T-shaped, U-shaped, and other irregular shapes. The arrangement pattern of the openings is not particularly limited and may be arranged regularly or irregularly, but from the viewpoint of achieving uniform breathability and strength throughout the composite, it is preferable that they are arranged regularly at predetermined intervals. From the viewpoint of achieving both breathability and strength in the composite, the pore size of the openings is preferably 0.1 mm or more and 3.0 mm or less, and the opening ratio is preferably 20% or less from the viewpoint of maintaining strength and dimensional stability.

In the present invention, "opening ratio" refers to the ratio of the sum of the areas of the openings to the surface area of the composite.

[Method of manufacturing the composite]
The method for producing the composite of the present invention preferably includes a step of dispersing an adhesive resin between the layers of the artificial leather and the woven or knitted fabric A. These steps will be described in detail below.

(1) Process for Forming Artificial Leather First, with regard to the fiber structure for artificial leather, methods for forming a substrate composed of ultrafine fibers include a method of directly spinning fibers having the above-mentioned average single fiber diameter to obtain a substrate, a method of first forming a sheet composed of ultrafine fiber-developing fibers described below and then developing ultrafine fibers having the above-mentioned average single fiber diameter from the sheet to form a substrate (a method via a sheet composed of ultrafine fiber-developing fibers), etc. Among these, the method of first passing through a sheet composed of ultrafine fiber-developing fibers is preferred from the viewpoint of excellent operability and the ability to obtain fibers with a uniform single fiber diameter.

As an ultrafine fiber-forming fiber, an islands-in-sea type composite fiber is used, in which thermoplastic resins with different solvent solubilities are used as a sea component (easily soluble polymer) and an island component (slightly soluble polymer), and the sea component is dissolved and removed using a solvent or the like to form the island component fibers with the aforementioned average single fiber diameter. The use of islands-in-sea type composite fiber makes it possible to create appropriate voids between the island components, i.e., between the ultrafine fibers within the fiber bundle, when the sea component is removed, which is preferable from the perspective of the soft texture and surface quality of the composite.

The preferred method for spinning ultrafine fiber-producing fibers with an islands-in-sea composite structure is to use a spinneret for islands-in-sea composite fibers, which uses a polymer inter-alignment system in which the sea component and island component components are mutually aligned and spun, from the perspective of obtaining ultrafine fibers with a uniform single fiber diameter.

The sea component of islands-in-sea composite fibers can be made from polyethylene, polystyrene, copolymer polyesters copolymerized with "sodium sulfoisophthalic acid or polyethylene glycol," as well as polylactic acid, polyvinyl alcohol, and their copolymers. However, from the standpoint of spinnability and ease of elution, polystyrene and copolymer polyesters are preferred.

When using the islands-in-sea composite fiber, it is preferable that the strength of the island components be 2.0 cN/dtex or more. By making the strength of the island components preferably 2.0 cN/dtex or more, more preferably 2.3 cN/dtex or more, and even more preferably 2.8 cN/dtex or more, the abrasion resistance of the composite is improved and a decrease in friction fastness due to fiber shedding can be suppressed.

In the present invention, the strength of the island components of the islands-in-sea type composite fiber is a value measured and calculated by the following method.
(1) Ten islands-in-the-sea composite fibers, each 20 cm long, are bundled together.
(2) After dissolving and removing the sea component from the sample of (1), the sample is air-dried.
(3) According to JIS L1013:2010 "Testing methods for chemical fiber filament yarns", "8.5 Tensile strength and elongation", "8.5.1 Standard time test", the test is carried out 10 times under the conditions of a grip length of 5 cm, a pulling speed of 5 cm/min, and a load of 2 N (N = 10).
(4) The arithmetic mean value (cN/dtex) of the test results obtained in (3) is rounded to one decimal place.

When the substrate is a nonwoven fabric, the spun ultrafine fiber-developing fibers are opened and then formed into a fiber web using a cross wrapper or the like, and then entangled to obtain a fiber structure containing a nonwoven fabric as a constituent element. Methods that can be used to entangle fiber webs and obtain a fiber structure containing a nonwoven fabric as a constituent element include needle punching and water jet punching.

As mentioned above, this nonwoven fabric can be in the form of either a short fiber nonwoven fabric or a long fiber nonwoven fabric, but with a short fiber nonwoven fabric, there are more fibers oriented in the thickness direction of the artificial leather than with a long fiber nonwoven fabric, and when raised, the surface of the composite can be made to have a high degree of density and a soft texture.

When the nonwoven fabric is a staple fiber nonwoven fabric, the islands-in-sea composite fibers obtained in the process of forming the islands-in-sea composite fibers are preferably subjected to crimping processing, cut to a predetermined length to obtain raw fibers, and then opened, laminated, and entangled to obtain the staple fiber nonwoven fabric. Known methods can be used for crimping and cutting.

When using a short-fiber nonwoven fabric, the average fiber length of the ultrafine fiber-developing fibers is preferably 25 mm or more and 90 mm or less. By setting the average fiber length to 90 mm or less, more preferably 80 mm or less, and even more preferably 70 mm or less, good quality and a soft feel can be obtained. On the other hand, by setting the average fiber length to 25 mm or more, more preferably 35 mm or more, and even more preferably 40 mm or more, a composite with excellent abrasion resistance can be obtained.

Furthermore, in an embodiment in which the fiber structure further includes a woven or knitted fabric b as a constituent element, a sheet made of ultrafine fiber-developing fiber obtained by the above-mentioned method and the woven or knitted fabric b can be laminated and then entangled together. To entangle the sheet made of ultrafine fiber-developing fiber and the woven or knitted fabric b, the woven or knitted fabric b can be laminated on one or both sides of the sheet made of ultrafine fiber-developing fiber, or the woven or knitted fabric b can be sandwiched between multiple sheets made of ultrafine fiber-developing fiber, and the fibers of the sheet made of ultrafine fiber-developing fiber and the woven or knitted fabric b can be entangled together by needle punching, water jet punching, or the like.

The apparent density of a sheet composed of ultrafine fiber-developing fibers after needle punching or water jet punching (hereinafter abbreviated as "entangled sheet", including those entangled and integrated with woven or knitted fabric b) is preferably 0.15 g/ ^cm3 or more and 0.45 g/ ^cm3 or less. By setting the apparent density to preferably 0.15 g/ ^cm3 or more, even if excessive tension is applied during the manufacturing stage, the fibers are less likely to slip through or stretch, improving the denseness of the fibers and resulting in a composite with good appearance quality. On the other hand, by setting the apparent density to preferably 0.45 g/ ^cm3 or less, sufficient space for imparting the polymer elastomer is maintained, and voids in the cross section are maintained, resulting in a composite with a soft texture.

It is also a preferred embodiment to subject the entangled sheet to a heat shrinking treatment using warm water or steam to improve the density of the fibers.

Next, the entangled sheet can be impregnated with an aqueous solution of a water-soluble resin and then dried to add the water-soluble resin. By adding a water-soluble resin to the entangled sheet, the fibers are fixed and dimensional stability is improved. Here, in this invention, the water-soluble resin refers to a resin that is soluble in water or hot water (water at 80°C to 100°C), and specific examples include polyacrylamide, polyvinyl alcohol, and carboxymethyl cellulose.

The resulting entangled sheet can then be treated with a solvent or solution to produce ultrafine fibers. This treatment is one method for forming ultrafine fibers with an average single fiber diameter of 1.0 μm or more and 10.0 μm or less. Hereinafter, an entangled sheet with ultrafine fibers produced will be referred to as an ultrafine fiber sheet.

Ultrafine fiber sheets can be formed using this method by immersing the entangled sheet in a solvent or solution to dissolve and remove the sea component of the islands-in-sea composite fibers.

When the sea component is polyethylene or polystyrene, organic solvents such as toluene or trichloroethylene can be used as the solvent for dissolving and removing the sea component. When the sea component is copolymer polyester or polylactic acid, an alkaline aqueous solution such as an aqueous sodium hydroxide solution can be used. When the sea component is water-soluble thermoplastic polyvinyl alcohol, hot water can be used.

Then, by impregnating an ultrafine fiber sheet or entangled sheet with a solution of the polymer elastomer and solidifying the polymer elastomer, a sheet with polymer elastomer containing the polymer elastomer can be formed. Methods for solidifying the polymer elastomer include impregnating an ultrafine fiber sheet or entangled sheet with a solution of the polymer elastomer, followed by wet coagulation or dry coagulation, and these methods can be selected appropriately depending on the type of polymer elastomer used.

When polyurethane is selected as the polymeric elastomer, N,N-dimethylformamide, dimethyl sulfoxide, etc. are preferably used as the solvent if the polyurethane is an organic solvent-based polyurethane. Furthermore, if the polyurethane is a water-dispersible polyurethane, a water-dispersible polyurethane liquid in which the polyurethane is dispersed in water as an emulsion may also be used.

If a polymeric elastomer is added to the entangled sheet, after the polymeric elastomer-coated sheet is formed, it can be treated with a solvent or solution to produce ultrafine fibers. The specific procedures are the same as those described above.

In this way, a sheet-like material can be formed that includes a fiber structure whose constituent elements are a substrate made of ultrafine fibers, and a polymeric elastomer. This can be sent to a subsequent process as artificial leather as is, but one surface of the resulting sheet-like material can then be ground to form artificial leather with raised nap. From the perspective of production efficiency, it is also preferred to cut the sheet-like material in half in the thickness direction to form two pieces of artificial leather before grinding the surface of the artificial leather.

Specifically, one surface of the sheet-like material (including a sheet-like material cut in half) can be ground using sandpaper, a roll sander, or the like to form artificial leather with raised nap. A lubricant such as a silicone emulsion can also be applied to the surface of the sheet-like material before grinding.

The product that has gone through the above steps may be used as is as artificial leather, but it is preferable to carry out various post-processing steps to produce artificial leather, as in the general manufacturing method of artificial leather. Of course, it goes without saying that artificial leather that has undergone post-processing is also treated as artificial leather in the present invention.

First, it is also preferable to dye the artificial leather. Examples of dyeing methods include jet dyeing using a jigger dyeing machine or jet dyeing machine, dip dyeing such as thermosol dyeing using a continuous dyeing machine, or printing on the napped surface using roller printing, screen printing, inkjet printing, sublimation printing, vacuum sublimation printing, etc. Among these, jet dyeing using a jet dyeing machine is preferred in terms of obtaining a soft texture and quality and grade.

The basis weight of the artificial leather of the composite of the present invention is measured according to "6.2 Mass per unit area (ISO method)" of JIS L1913:2010 "Testing methods for general nonwoven fabrics," and is preferably 50 g/ ^m2 or more and 600 g/ ^m2 or less. By setting the basis weight of the artificial leather to 50 g/ ^m2 or more, more preferably 80 g/ ^m2 or more, a composite with a more substantial feel and excellent texture can be obtained. On the other hand, by setting the basis weight of the artificial leather to 600 g/ ^m2 or less, more preferably 500 g/ ^m2 or less, a more flexible composite can be obtained.

Furthermore, if necessary, designs can be applied to the surface. For example, post-processing such as perforation, embossing, laser processing, pinsonic processing, and printing can be performed. Of course, it is also preferable to perform these post-processing processes on artificial leather before dyeing.

(2) A step of dispersing the adhesive resin (a step of forming a composite)
Next, an adhesive resin is dispersed between the layers of the artificial leather and the woven or knitted fabric (a), thereby obtaining a composite.

In the method for producing a composite according to the present invention, the basis weight of the woven/knitted fabric a in the composite production stage is preferably 50 g/ ^m2 or more and 300 g/ ^m2 or less. By setting the basis weight of this woven/knitted fabric a to preferably 50 g/ ^m2 or more, more preferably 70 g/ ^m2 , a composite with excellent flame retardancy and strength can be obtained. Furthermore, by setting the basis weight of this woven/knitted fabric a to 300 g/ ^m2 or less, more preferably 250 g/ ^m2 , a composite with excellent flexibility can be obtained.

In the present invention, the basis weight of woven or knitted fabric a at the composite manufacturing stage refers to the value measured in accordance with "6.2 Mass per unit area (ISO method)" of JIS L1913:2010 "General nonwoven fabric testing methods."

In the method for producing a composite according to the present invention, the tensile strength of the woven or knitted fabric a during the composite production stage is preferably 80 N/5 cm or more and 1500 N/5 cm or less, as the average value of the tensile strength in any two orthogonal directions. Setting this average tensile strength to 80 N/5 cm or more, more preferably 100 N/5 cm or more, and even more preferably 150 N/5 cm or more, is preferred, as this will result in excellent shape stability and durability when made into a composite. Furthermore, setting the average tensile strength to 1500 N/5 cm or less, more preferably 1200 N/5 cm or less, and even more preferably 1000 N/5 cm or less will result in excellent moldability when made into a composite.

In the present invention, the tensile strength of woven/knitted fabric a at the composite manufacturing stage refers to the value measured in accordance with "6.3.1 Tensile strength and elongation (ISO method)" of JIS L1913:2010 "General nonwoven fabric testing methods."

The adhesive for the composite of the present invention can be applied in a predetermined amount using devices such as a rotary screen, knife roll coater, gravure roll coater, kiss roll coater, or calendar coater. As long as a certain level of precision is maintained in the amount applied, it is also possible to directly dispense the hot melt resin that serves as the adhesive resin onto the woven or knitted fabric (a), or to place a nonwoven fabric composed of the adhesive resin (limited to those in which the adhesive resin can exist in a discrete state, as described above). Among these, in order to achieve a good texture for the composite, it is preferable to use a rotary screen or gravure roll coater to arrange the adhesive resin so that it exists in a discrete state, as exemplified in Figures 2 to 5. This prevents the composite from hardening in texture or reducing breathability.

As for the bonding method for the composite of the present invention, if the adhesive resin is a wet-curing resin, bonding is promoted by placing it in an appropriate temperature and humidity environment (also known as "curing"). Furthermore, if a thermoplastic resin is used as the adhesive resin, the components are integrated by thermocompression bonding. Thermocompression bonding can be achieved using methods such as heat rolls.

The amount of adhesive resin can be varied depending on the surface condition of the woven/knitted fabric (a) or artificial leather to be bonded and the type of adhesive resin, but is preferably 2 g/ ^m2 or more and 80 g/ ^m2 or less. By setting the amount of adhesive resin to preferably 2 g/ ^m2 or more, more preferably 5 g/ ^m2 or more, the adhesive strength between layers is improved. On the other hand, by setting the amount of adhesive resin to preferably 80 g/m2 or ^less , more preferably 70 g/ ^m2 or less, the flexibility of the composite is improved.

[Vehicle interior materials, seats]
The composite of the present invention is smooth and has good surface quality and texture, as well as strength and flame retardancy, and is therefore suitable for a wide range of applications, including industrial materials such as clothing, miscellaneous goods, shoe and bag applications, vehicle interior materials, seats, polishing pad substrates, various polishing cloths, and wiping cloths.

In particular, vehicle interior materials containing the composite are preferred because they can take advantage of the excellent flame retardancy and strength properties. Examples of such vehicle interior materials include interior materials used in vehicle parts such as automobile steering wheels, horn switches, shift knobs, dashboards, instrument panels, glove compartments, floor carpets, floor mats, ceiling linings, sun visors, and assist grips, and it is more preferable for these vehicle parts to contain the composite. In this invention, "vehicle" includes automobiles, aircraft, railroad cars, and ships, as well as carriages, carriages, rickshaws, and other vehicles, as well as some industrial, construction, and agricultural machinery capable of carrying people or animals, such as excavators, cranes, tractors, and combine harvesters.

Also, seats containing the above-mentioned composite are similarly preferred, as they can take advantage of these properties in applications requiring flame retardancy and strength. It is more preferable for such seats that at least a portion of the covering material, such as the headrest, seat, armrest, or footrest, i.e., the portion that comes into direct contact with the seated person, is made of the above-mentioned composite. Naturally, the seat of the present invention can be used not only for vehicles such as automobiles, aircraft, railway vehicles, and ships, but also for homes, offices, and stores. It should be noted that the term "seat" as used in this invention also includes chairs, benches, sofas, couches, stools, and floor chairs.

Next, the present invention will be explained in more detail using examples, but the present invention is not limited to these examples.

[Measurement method and evaluation processing method]
Unless otherwise specified, the measurements of each physical property were carried out according to the above-mentioned methods.

(1) Average single fiber diameter of ultrafine fibers (μm):
The average single fiber diameter of the ultrafine fibers was measured and calculated by the above-mentioned method using a scanning electron microscope "VHX-D500/D510" manufactured by Keyence Corporation.

(2) Pile length (μm):
The nap length of the artificial leather was measured and calculated by the above-mentioned method using a scanning electron microscope, "VHX-D500/D510 model" manufactured by Keyence Corporation.

(3) Thickness (mm):
The thickness of the composite was measured and calculated using the method described above, using a Dial Thickness Gauge H-1A manufactured by Ozaki Seisakusho Co., Ltd. The thickness of the artificial leather was measured and calculated in the same manner as the thickness of the composite.

(4) Weight (g/m ² ):
The basis weight of the composite was measured and calculated by the method described above. The basis weights of the artificial leather and woven/knitted fabric a were measured and calculated in the same manner as the thickness of the composite.

(5) Tensile strength (N/5cm):
The tensile strength of the composite was measured and calculated by the above-mentioned method using a tensile tester, Model: 3343, manufactured by Instron Corp. The tensile strength of the artificial leather and woven/knitted fabric a was measured and calculated in the same manner as the thickness of the composite.

(6) Weave density (threads/2.54 cm)
The weave density of the woven/knitted fabric a was measured and calculated by the following method.
(i) Five test pieces measuring 6 cm x 6 cm were taken at random from the woven/knitted fabric a.
(ii) The number of warp and weft yarns present in the 5.08 cm section was counted.
(iii) The number of warp and weft yarns present in the 5.08 cm section was divided by 2 to calculate the weave density of the warp and weft yarns of each sample. The arithmetic mean value (numbers/2.54 cm) of the five test pieces was rounded to one decimal place to calculate the weave density of woven/knitted fabric a.

(7) Content of modacrylic fiber in woven/knitted fabric a (% by mass)
The content of modacrylic fiber in woven or knitted fabric a was evaluated by the above-mentioned dissolution method. The specific method was as follows.
(i) Three test pieces measuring 10 cm x 10 cm were taken at random from the woven/knitted fabric a.
(ii) The test piece was immersed in DMF to dissolve the modacrylic fiber, and then dried for 24 hours at 25° C. The mass ratio of the test piece before and after dissolution was calculated using the following formula, and the arithmetic average (%) of the three test pieces was rounded to one decimal place to calculate the modacrylic fiber content: (sample mass (g) before dissolution - sample mass (g) after dissolution and drying) / (sample mass (g) before dissolution) × 100 (formula).

(8) Content of modacrylic fiber in the composite (mass%)
The content of modacrylic fiber in the composite was evaluated and measured by the following method.
(i) The weight of the modacrylic fiber calculated when evaluating the content of modacrylic fiber in woven or knitted fabric a (sample mass before dissolution (g) - sample mass after dissolution and drying (g)) was multiplied by 100 to calculate the basis weight of the modacrylic fiber (g/m ² ).
(ii) The weight per unit area of the modacrylic fiber was divided by the weight per unit area of the composite and multiplied by 100 to calculate the content (mass%) of the modacrylic fiber in the composite.

(9) Opening ratio (%) of the composite:
The aperture ratio of the composite was determined by taking a photograph of a 20 cm × 20 cm composite surface using an electron microscope (for example, "Digital Microscope VHX-1000" manufactured by Keyence Corporation), determining the sum of the areas of the openings using a "circle area measurement" function, and calculating the ratio to the composite surface. This procedure was carried out for five samples, and the aperture ratio was determined as an arithmetic average.

(10) Combustibility of the composite (mm/min):
The flammability of the composite was evaluated according to the method described above.

(11) Complexity:
The composite was evaluated for flaws by placing the composite on urethane foam, dropping 3 cc of water onto the surface, leaving it to dry naturally, and then observing whether there were any abnormalities in appearance such as ring stains on the sample surface. If ring stains or the like were clearly visible to the naked eye, the result was rated as "present."

(12) Surface quality of the composite:
The surface quality of the composite was evaluated by a total of 20 healthy adult males and females, consisting of 10 healthy adult males and 10 healthy adult females. Composites measuring 200 mm square or larger were evaluated on a 5-point scale as shown below, with the most frequently received evaluation being taken as the surface quality. In the present invention, a good level is "Grade 3 to Grade 5." This evaluation was not performed on Example 5, which had a surface resin layer.
Grade 5: The surface of the composite is smooth to the touch and finger marks are visible.
・Level 4: A rating between Level 5 and Level 3.
Grade 3: The surface of the composite feels frictional resistance to the touch, but finger marks are visible.
・Level 2: An evaluation between Level 3 and Level 1.
Grade 1: The surface of the composite feels frictional and there are almost no finger marks.

(13) Texture of the composite:
A total of 20 healthy adult males and females, 10 of whom were healthy, conducted a sensory evaluation. The composites were cut into 300 mm squares and evaluated as follows based on the feel when held in the palm of the hand, with the most common evaluation being taken as the texture of the composite. In the case of a tie, the higher evaluation was taken as the texture of the composite. In the present invention, a good level is "grade 3 or 4."
Grade 4: Flexible and drapeable, with a good texture. Grade 3: Slightly flexible and drapeable, with a good texture. Grade 2: Slightly stiff, with little drapeability, with a poor texture. Grade 1: Stiff, with no drapeability, with a poor texture.

[Artificial leather]
The artificial leathers used in the Examples and Comparative Examples were produced as illustrated in the following Production Examples 1-A to 1-D.

[Production Example 1-A] (Artificial leather A)
(Islands-in-the-sea type composite fiber)
Using polystyrene as the sea part and polyethylene terephthalate (referred to as PET in Table 1) having an intrinsic viscosity (IV value) of 0.72 as the island parts, an islands-in-sea type composite fiber was obtained with a conjugation ratio of 20 mass% of the sea part and 80 mass% of the island parts, with 16 islands/filament and an average single fiber diameter of 20 μm.

(entangled sheet)
The resulting islands-in-sea composite fibers were cut into staples with a fiber length of 51 mm, and the staples were passed through a card and a cross wrapper to form a fiber web. The fiber web was then needle-punched to produce an entangled sheet with a basis weight of 550 g/ ^m2 and a thickness of 2.50 mm.

(PVA sheet)
The entangled sheet obtained as described above was shrunk with hot water at 96°C. The entangled sheet that had been shrunk with hot water was then impregnated with an aqueous solution of polyvinyl alcohol (hereinafter sometimes abbreviated as PVA) with a saponification degree of 88%, which had been adjusted to a concentration of 5% by mass. The sheet was then squeezed with a roll and dried with hot air at 125°C for 10 minutes while causing migration of the PVA, to obtain a PVA-attached sheet in which the PVA mass relative to the sheet mass was 45% by mass.

(ultrafine fiber sheet)
The resulting PVA-attached sheet formed by entanglement of ultrafine fiber bundles was immersed in trichloroethylene, squeezed with a mangle, and compressed 10 times, thereby dissolving and removing the sea component (sea removal) and compressing the PVA-attached sheet, to obtain an ultrafine fiber sheet.

(Sheet with polymer elastic body)
The ultrafine fiber sheet obtained as described above was immersed in a DMF solution of polyurethane containing organic solvent-based polyurethane as the main component, adjusted to a solids concentration of 12% by mass, and then the polyurethane resin was coagulated in an aqueous solution with a DMF concentration of 30% by mass. Thereafter, the sheet was dried with hot air at a temperature of 110°C for 10 minutes to obtain a sheet with a polymeric elastomer having a thickness of 2.00 mm.

(Sheet-like material)
The polymeric elastomer-attached sheet obtained as described above was cut in half in the thickness direction, and the surface formed by the cutting in half (the cut surface) was ground with endless sandpaper of sandpaper count 240 to obtain a sheet-like material having nap and a thickness of 0.60 mm.

(artificial leather)
The napped sheet thus obtained was dyed with a black dye at 125°C using a jet dyeing machine, and then dried in a dryer to obtain artificial leather with ultrafine fibers having an average single fiber diameter of 4.4 µm. The results are shown in Table 1.

[Production Example 1-B] (Artificial leather B)
An artificial leather was obtained in the same manner as in Production Example 1-A, except that a DMF (dimethylformamide) solution of polyurethane adjusted to a solids concentration of 30% was applied by gravure coating to the napped surface (surface) of the artificial leather of Production Example 1-A, and then dried to form a surface resin layer of 10 g/ ^m2 . The results are shown in Table 1.

[Production Example 1-C] (Artificial leather C)
An artificial leather was obtained in the same manner as in Production Example 1-A, except that the entangled sheet of Production Example 1-A was changed to a basis weight of 450 g/m ² and a thickness of 2.00 mm, and a sheet with a polymer elastomer having a thickness of 1.50 mm was produced, and then a napped sheet-like product having a thickness of 0.45 mm was produced. The results are shown in Table 1.

[Production Example 1-D] (Artificial leather D)
Artificial leather was obtained in the same manner as in Production Example 1-A, except that the entangled sheet of Production Example 1-A was changed to the following entangled sheet, and after a sheet with a polymer elastomer having a thickness of 2.30 mm was produced, a napped sheet-like product having a thickness of 0.90 mm was subsequently produced. The results are shown in Table 1.
(Entangled sheet of Production Example 1-D)
A plain weave fabric (woven/knitted fabric b) was sandwiched between the top and bottom of the fiber web, with the yarns made from polyethylene terephthalate having an intrinsic viscosity (IV value) of 0.72, each having a single fiber diameter of 10 μm for the warp and weft, a twist of 2500 T/m, and a weave density of 95 x 76 (warp x weft) per 2.54 cm (1 inch). The fabric/fiber web/fabric was then laminated and needle-punched to produce an entangled sheet with a basis weight of 700 g/ ^m2 and a thickness of 3.00 mm.

[Woven and knitted fabric a]
The woven and knitted fabrics a used in the examples and comparative examples were prepared as exemplified in the following Production Examples 2-A to 2-F.

[Production Example 2-A] (Woven/knitted fabric a-A)
The following woven and knitted fabrics a were obtained. The results are shown in Table 2.
Warp 1:
- Modacrylic fiber spun yarn with an LOI value of 32 (referred to as "MOD" in Table 2)
Short fiber fineness: 1.7 dtex
Short fiber length: 38 mm
-Spun yarn fineness: 295 dtex
Number of twists: 15 times/2.54 cm
Warp 2:
Polyethylene terephthalate multifilament (referred to as "PET" in Table 2)
- Single filament fineness of long fibers: 3.1 dtex
・Number of single multifilament yarns (filament count): 96 ・Total fineness of multifilament: 330 dtex
Weft 1:
- Modacrylic fiber spun yarn (MOD) with an LOI value of 32
Short fiber fineness: 1.7 dtex
Short fiber length: 38 mm
-Spun yarn fineness: 295 dtex
Number of twists: 15 times/2.54 cm
Weft 2:
- Polyethylene terephthalate multifilament (PET)
- Single filament fineness of long fibers: 3.1 dtex
Number of single multifilament yarns (filament count): 96 Total fineness of multifilament: 330 dtex Weave:
- Plain weave with warp threads 1 and 2 woven at a density ratio of 100:0 (only warp thread 1 is used) and weft threads 1 and 2 woven at a density ratio of 50:50 - Weave density: warp direction: weft direction = 74 threads/2.54 cm: 58 threads/2.54 cm
Other characteristics:
-Weight: 170 g/m ² .

[Production Example 2-B] (Woven/knitted fabric a-B)
A woven/knitted fabric a was obtained in the same manner as in Production Example 2-A, except that the weave structure of Production Example 2-A was changed to the following weave structure. The basis weight was 165 g/ ^m2 . The results are shown in Table 2.
Woven structure:
- A plain weave in which weft yarn 1 and weft yarn 2 are woven together at a density ratio of 80:20.

[Production Example 2-C] (Woven/knitted fabric a-C)
A woven/knitted fabric a was obtained in the same manner as in Production Example 2-A, except that the weave structure of Production Example 2-A was changed to the following weave structure. The basis weight was 173 g/ ^m2 . The results are shown in Table 2.
Woven structure:
- A plain weave in which weft thread 1 and weft thread 2 are woven together at a density ratio of 5:95.

[Production Example 2-D] (Woven/knitted fabric a-D)
A woven/knitted fabric a was obtained in the same manner as in Production Example 2-A, except that the weave structure of Production Example 2-A was changed to the following weave structure. The basis weight was 158 g/ ^m2 . The results are shown in Table 2.
Woven structure:
- A plain weave in which weft thread 1 and weft thread 2 are woven together at a density ratio of 100:0 (only weft thread 1 is used).

[Production Example 2-E] (Woven/knitted fabrics a-E)
A woven/knitted fabric a was obtained in the same manner as in Production Example 2-A, except that the weave structure of Production Example 2-A was changed to the following weave structure. The basis weight was 176 g/ ^m2 . The results are shown in Table 2.
Woven structure:
- Plain weave structure in which warp yarn 1 and warp yarn 2 are woven at a density ratio of 0:100 (only warp yarn 2 is used), and weft yarn 1 and weft yarn 2 are woven at a density ratio of 0:100 [Manufacturing Example 2-F] (Woven/knitted fabric a-F)
A woven or knitted fabric a was obtained in the same manner as in Production Example 2-A, except that the warp yarn 1 and weft yarn 1 of Production Example 2-A were changed to the following warp yarn 3 and weft yarn 3. The basis weight was 190 g/ ^m2 . The results are shown in Table 2.
Warp 3:
Spun yarn of meta-aramid fiber with an LOI value of 32 (denoted as "MET" in Table 2)
Weft 3:
- Spun yarn of meta-aramid fiber (MET) with an LOI value of 32.

[Example 1]
Artificial leather A was used as the artificial leather, woven/knitted fabric a-A was used as the woven/knitted fabric a, and a moisture-curing reactive urethane adhesive with a melt viscosity of 2000 mPa·s at 125°C was used as the adhesive resin. The adhesive resin was dispersed on the surface (back surface) of artificial leather A opposite the napped surface using a gravure roll coater in the pattern shown in Figure 2 (dot pattern, adhesive resin basis weight: 10 g/m ² , center-to-center distance of each dot: 1.2 mm). Woven/knitted fabric a-A was then layered on top of the composite, and the resulting composite was nipped with a pair of calendar rolls at a roll surface temperature of 90°C. The composite was then aged for 24 hours in an environment with an ambient temperature of 25°C and a relative humidity of 50% to obtain a composite. The results are shown in Table 3.

[Example 2]
A composite was obtained in the same manner as in Example 1, except that woven/knitted fabric a-A was changed to woven/knitted fabric a-B. The results are shown in Table 3.

[Example 3]
A composite was obtained in the same manner as in Example 2, except that artificial leather A was changed to artificial leather B. The results are shown in Table 3.

[Example 4]
A composite was obtained in the same manner as in Example 1, except that woven/knitted fabric aA was changed to woven/knitted fabric aC. The results are shown in Table 3.

[Example 5]
A composite was obtained in the same manner as in Example 1, except that artificial leather A was changed to artificial leather C. The results are shown in Table 3.

[Example 6]
A composite was obtained in the same manner as in Example 1, except that the artificial leather A was changed to the artificial leather D and the woven/knitted fabric a was changed to the woven/knitted fabric a-D. The results are shown in Table 3.

[Example 7]
A composite was obtained in the same manner as in Example 1, except that artificial leather A was changed to artificial leather D and openings were formed in the obtained composite using a punching board with needles (needle diameter: 1.4 mm, vertical pitch: 5 mm, horizontal pitch: 5 mm, opening rate: 12%) to form a composite with openings. The results are shown in Table 3.

[Comparative Example 1]
A composite to which a flame retardant was dip-imparted was obtained in the same manner as in Example ¹ , except that woven/knitted fabric a-A was replaced with woven/knitted fabric a-E, the resulting composite was impregnated with an aqueous solution of guanidine phosphate as a flame retardant so that the deposition amount was 15 g/m², the composite was wrung out with a mangle, and then dried in a dryer. The results are shown in Table 4.

[Comparative Example 2]
A flame retardant containing 70% by mass of silicon oxide resin-treated ammonium polyphosphate (manufactured by Wellchem, phosphorus content 28%, nitrogen content 14%) was applied to the surface of the composite facing the woven or knitted fabric a-E using a screen coater, followed by drying at 100°C for 7 minutes to obtain a composite coated on the back side with a flame retardant-containing resin in the same manner as in Comparative Example 1, except that the dried amount of flame retardant-containing resin was adjusted to 70 g/ ^m2 . The results are shown in Table 4.

[Comparative Example 3]
A composite coated with a flame retardant on the back side was obtained in the same manner as in Example 6, except that woven/knitted fabrics a-D were not laminated, and a flame retardant containing 70% by mass of silicon oxide resin-treated ammonium polyphosphate (manufactured by Wellchem, phosphorus content 28%, nitrogen content 14%) was applied to the surface of the composite facing woven/knitted fabric a using a screen coater, followed by drying at 100°C for 7 minutes to achieve a dried deposition amount of the flame retardant-containing resin of ⁷⁰ g/m2. The results are shown in Table 4.

[Comparative Example 4]
A composite was obtained in the same manner as in Example 6, except that woven/knitted fabric aD was replaced with woven/knitted fabric aF. The results are shown in Table 4.

[Comparative Example 5]
A composite was obtained in the same manner as in Example ⁶ , except that woven/knitted fabric a-D was replaced with woven/knitted fabric a-A, and in the composite formation step, a moisture-curing polyurethane resin was applied to the entire surface using a roll coater to a coating amount of 25 g/m2. The results are shown in Table 4.

All of the composites obtained in Examples 1 to 7 were smooth and had good surface quality and texture, as well as good strength and flame retardancy.

On the other hand, the composite of Comparative Example 1 was rough and had poor surface quality. Furthermore, the composites of Comparative Examples 2, 3, and 5 all had poor texture. The composite of Comparative Example 4 had poor flame retardancy.

1: Composite; 2: Raised portion; 3: Boundary line between raised portion and other portion (line connecting the intersection of fibers oriented in the thickness direction and fibers oriented in the surface direction of the artificial leather)
4: Arrow indicating the distance from the intersection of the fiber oriented in the thickness direction and the fiber oriented in the plane direction of the artificial leather to the tip of the nap 5: Artificial leather 6: Woven/knitted fabric a
7: Adhesive resin

Claims (7)

A composite in which artificial leather and a woven or knitted fabric (a) are laminated adjacent to each other,
The artificial leather is
A fiber structure including, as a component, a substrate made of ultrafine fibers;
A polymeric elastomer;
Including,
The woven or knitted fabric a contains modacrylic fibers,
An adhesive resin is dispersed between the layers of the artificial leather and the woven or knitted fabric a.
Complex. The composite described in claim 1, wherein the polyester fiber content in the woven or knitted fabric a is 5% by mass or more and 50% by mass or less. The composite according to claim 1 or 2, wherein the modacrylic fiber content in the composite is 20% by mass or more and 50% by mass or less. The composite according to claim 1 or 2, wherein the fiber structure further comprises woven or knitted fabric b. A vehicle interior material comprising the composite of claim 1 or 2. A vehicle part comprising the composite material according to claim 1 or 2. A seat comprising the composite of claim 1 or 2.