阅读说明：本技术 合成皮革及被覆物品 (Synthetic leather and coated article ) 是由 原田大 于 2020-04-17 设计创作，主要内容包括：提供合成皮革及由合成皮革被覆的被覆物品,合成皮革可得到不仅机械强度、耐久性优异,而且具有高阻燃性、质地优异的被覆物品。合成皮革具有由包含非熔融纤维A和热塑性纤维B的无纺布形成的纤维基材层,其中,所述非熔融纤维A的高温收缩率为3％以下、且基于ISO22007-3(2008年)的热导率为0.060W/m·K以下,所述热塑性纤维B的基于JIS K 7201-2(2007年)的LOI值为25以上,本发明的被覆物品为由该合成皮革被覆而成的被覆物品。(Synthetic leather and coated articles coated with the synthetic leather are provided, and the synthetic leather can obtain coated articles which not only have excellent mechanical strength and durability, but also have high flame retardancy and excellent texture. The synthetic leather has a fibrous base layer formed of a nonwoven fabric comprising non-melting fibers A and thermoplastic fibers B, wherein the non-melting fibers A have a high-temperature shrinkage of 3% or less and a thermal conductivity of 0.060W/m.K or less in accordance with ISO22007-3 (2008), and the thermoplastic fibers B have an LOI value of 25 or more in accordance with JIS K7201-2 (2007), and the coated article of the present invention is a coated article coated with the synthetic leather.)

1. A synthetic leather having a fibrous base layer formed of a nonwoven fabric comprising non-molten fibers A and thermoplastic fibers B, wherein the non-molten fibers A have a high-temperature shrinkage of 3% or less and a thermal conductivity of 0.060W/m.K or less in accordance with ISO22007-3 (2008), and the thermoplastic fibers B have an LOI value of 25 or more in accordance with JIS K7201-2 (2007).

2. The synthetic leather according to claim 1, wherein a resin layer is formed on the fibrous base material layer.

3. The synthetic leather of claim 2, wherein an adhesive layer is provided between the fibrous base material layer and the resin layer.

4. The synthetic leather according to claim 2 or 3, wherein the synthetic leather has a penetration depth of the skin resin layer or the adhesive layer in the fibrous base material layer of 0.05 to 0.40 mm.

5. A synthetic leather according to any one of claims 1 to 4, wherein the content of the non-fused fibers A in the fibrous base material layer is 15 to 70% by mass.

6. The synthetic leather according to any one of claims 1 to 5, wherein the fibers C other than the non-melted fibers A and the thermoplastic fibers B are contained in an amount of 20 mass% or less.

7. The synthetic leather according to any one of claims 1 to 6, wherein the non-melting fiber A is a flame-resistant fiber or a meta-aramid fiber.

8. A synthetic leather according to any one of claims 1 to 7, wherein the thermoplastic fibers B are fibers formed from a resin selected from the group consisting of flame retardant liquid crystalline polyesters, flame retardant poly (alkylene terephthalates), flame retardant poly (acrylonitrile-butadiene-styrene), flame retardant polysulfones, poly (ether-ketones), poly (ether-ketone-ketones), polyethersulfones, polyarylates, polyarylene sulfides, polyphenylsulfones, polyetherimides, polyamideimides and mixtures thereof.

9. A synthetic leather according to any one of claims 1 to 8, wherein said thermoplastic fibers B are fibers containing 15 mass% or more of sulfur atoms.

10. A synthetic leather according to any one of claims 1 to 9, wherein the synthetic leather comprises the fibrous base material layer in an amount of 20 to 80% by mass.

11. A coated article coated with the synthetic leather according to any one of claims 1 to 10.

12. The coated article according to claim 11, wherein the article is a seat cushion material mounted on an aircraft, an automobile, or a ship.

Technical Field

The present invention relates to synthetic leather and a coated article coated with synthetic leather.

Background

In recent years, synthetic leather has been used in a wide range of fields such as interior materials for airplanes, automobiles, railways, buildings, interior materials for furniture, and the like as substitutes for natural leather. Synthetic leathers used for interior materials for vehicles such as airplanes and automobiles, and skin materials for furniture are required to have soft texture, flexibility, mechanical strength, and durability. Since the above materials have a disadvantage of being easily combustible, flame retardant properties are required.

For example, there are FMVSS-302, JIS D-1201 in the automobile interior material aspect; the aspects of the interior materials for railways include a non-metallic material test method for railway vehicles and a 45-degree ethanol method; there are JIS A-1321 and the like as wall-mounted materials, and high flame retardancy is required to meet these standards.

Further, in the case of the aircraft sheet, in addition to the flame retardancy of the synthetic leather alone, such as the 12 second or 60 second vertical burning test, the flame retardancy by the gasoline burner test as the whole sheet, which is obtained by compounding the skin material, such as the synthetic leather, on the seat cushion material, is required, and the higher flame retardancy is required.

Synthetic leather is formed by laminating a surface resin layer such as polyurethane, polyolefin, polyvinyl chloride, or the like on a fiber base material layer such as woven fabric, knitted fabric, nonwoven fabric, or the like. In addition, an adhesive layer may be present between the fiber base material layer and the surface resin layer.

For flame retardancy of synthetic leather, a method of flame-retarding at least one or more of a fiber base material layer, a skin resin layer and an adhesive layer has been reported, and the method is roughly classified into a method of using a fiber having high flame retardancy among fibers constituting a fiber base material layer and a method of flame-retarding by post-processing. In recent years, flame retardancy without using halogen-based flame retardants has been strongly required from the viewpoint of environmental protection and the harmfulness of gases generated during combustion, and phosphorus-based flame retardants such as ammonium phosphate, ammonium sulfamate, ammonium sulfate, borax, boric acid, aluminum hydroxide, magnesium hydroxide, and phosphate, and non-halogen-based flame retardants such as hydroxide are known.

In general, when the amount of the flame retardant required to produce a flame retardant effect is added, there are problems that thickening or breaking (stickiness) occurs in a synthetic resin emulsion or a solution, the film strength of the resin is reduced, the heat resistance is reduced, and the texture is reduced in the case of a water-soluble flame retardant. There are problems that the water resistance is poor, wrinkles are generated when the flame retardant is brought into contact with water, and the flame retardant performance itself is lowered. In order to solve such a problem, a phosphorus flame retardant having a specific structure is disclosed (patent document 1).

Further, there is disclosed a method of improving flame retardancy as a fiber base material layer by incorporating a flame retardant into fibers constituting the fiber base material layer so that an LOI value of the fibers themselves is 25 or more (patent document 2).

Documents of the prior art

Patent document

Patent document 1: international publication No. 2013-187492

Patent document 2: japanese laid-open patent application No. 2010-77554

Disclosure of Invention

Problems to be solved by the invention

However, in the conventional flame-retardant synthetic leather, although the synthetic leather alone passes FMVSS-302, JIS D-1201, non-metallic material test method for railway vehicles, 45 degree ethanol method for automobile interior materials; JIS A-1321 for wall-mounted materials; in the flame-retardant test such as the 12-second or 60-second vertical burning test for an aircraft sheet, when the sheet is formed by compounding the sheet as a skin material with a seat cushion material, the resultant sheet as a whole does not have flame-retardant performance to such an extent that the sheet can withstand the gasoline burner test, and a thick felt of aramid or inorganic fiber needs to be disposed between the flame-retardant synthetic leather and the seat cushion material as a flame-retardant layer. The sheet having the flame retardant layer disposed in this manner has a problem that the sheet is not only hard but also large in volume and heavy in mass.

In the method described in patent document 1, after the fiber base material layer is integrated with the urethane resin layer by applying a flame retardant to the fiber base material layer by dipping, and then backing processing is performed with a resin containing a flame retardant, the synthetic leather alone passes a flame retardant standard test for various applications, but when the synthetic leather is integrated with the seat cushion material, the seat cushion material inside is heated by a gasoline burner for a certain period of time, and therefore, the standard of the aircraft seat cushion material is not satisfied unless a flame retardant layer formed of an aramid felt is disposed.

Further, when a nonwoven fabric felt having an LOI value of 25 or more is produced by using flame-retardant polyethylene terephthalate having an LOI value of 25 or more blended with a flame retardant according to the method described in patent document 2 and synthetic leather is produced, holes are formed by heating of a gasoline burner, and a cushion member is ignited when the nonwoven fabric felt is integrated with a seat cushion, and thus sufficient flame retardancy cannot be obtained.

That is, as the flame-retardant synthetic leather for the aircraft sheet, there has been proposed no synthetic leather having excellent flame retardancy, which has a sufficient degree of flame retardancy even if a flame retardant layer is not provided between the synthetic leather and the seat cushion material or the flame retardant layer is made thinner and lighter when the synthetic leather is integrated with the seat cushion material. This makes it possible to reduce the weight of the entire aircraft sheet and save space, and also to improve the ride comfort by improving the cushioning properties.

Accordingly, an object of the present invention is to provide synthetic leather that can provide a coated article having high flame retardancy and excellent texture, in addition to excellent mechanical strength and durability, and a coated article coated with the synthetic leather.

Means for solving the problems

The present invention adopts the following means to solve the above problems.

(1) A synthetic leather having a fibrous base layer formed of a nonwoven fabric comprising non-molten fibers A and thermoplastic fibers B, wherein the non-molten fibers A have a high-temperature shrinkage of 3% or less and a thermal conductivity of 0.060W/m.K or less in accordance with ISO22007-3 (2008), and the thermoplastic fibers B have an LOI value of 25 or more in accordance with JIS K7201-2 (2007).

(2) The synthetic leather according to (1), wherein a resin layer is formed on the fibrous base material layer.

(3) The synthetic leather according to (2), wherein an adhesive layer is provided between the fibrous base material layer and the resin layer.

(4) The synthetic leather according to (2) or (3), wherein the synthetic leather has a penetration depth of the skin resin layer or the adhesive layer in the fibrous base material layer of 0.05 to 0.40 mm.

(5) The synthetic leather according to any one of (1) to (4), wherein the content of the non-fused fibers A in the fibrous base layer is 15 to 70% by mass.

(6) The synthetic leather according to any one of (1) to (5), wherein the fibers C other than the non-melted fibers A and the thermoplastic fibers B are contained in an amount of 20% by mass or less.

(7) The synthetic leather according to any one of (1) to (6), wherein the non-melting fiber A is a flame-resistant fiber or a meta-aramid fiber.

(8) The synthetic leather according to any one of (1) to (7), wherein the thermoplastic fiber B is a fiber formed of a resin selected from the group consisting of flame-retardant liquid-crystalline polyesters, flame-retardant poly (alkylene terephthalates), flame-retardant poly (acrylonitrile-butadiene-styrene), flame-retardant polysulfones, poly (ether-ketones), poly (ether-ketone-ketones), polyether sulfones, polyarylates, polyarylene sulfides, polyphenylene sulfones, polyetherimides, polyamideimides, and mixtures thereof.

(9) The synthetic leather according to any one of (1) to (8), wherein the thermoplastic fibers B are fibers containing 15 mass% or more of sulfur atoms.

(10) The synthetic leather according to any one of the above items (1) to (9), wherein the synthetic leather has a fiber base material layer in an amount of 20 to 80% by mass.

(11) A coated article coated with the synthetic leather according to any one of (1) to (10).

(12) The coated article according to (11), wherein the article is a seat cushion material mounted on an aircraft, an automobile, or a ship.

Effects of the invention

The synthetic leather of the present invention is excellent in mechanical strength and durability, and has high flame retardancy. Further, since the coated article coated with the synthetic leather has the above-described structure, it is soft and has excellent mechanical strength and durability, and also has high flame retardancy.

Drawings

Fig. 1 is an explanatory view for explaining a method of assembling a coated article used in a combustion test of an aircraft seat cushion material and the combustion test.

FIG. 2 is a cross-sectional view of the synthetic leather of the present invention for measuring the penetration depth of a resin layer or an adhesive layer into a fiber base material layer.

Detailed Description

The present invention is a synthetic leather and a coated article coated with the synthetic leather, characterized by having a fibrous base layer formed of a nonwoven fabric comprising non-melting fibers A and thermoplastic fibers B, wherein the non-melting fibers A have a high-temperature shrinkage of 3% or less and a thermal conductivity of 0.060W/m.K or less according to ISO22007-3 (2008), and the thermoplastic fibers B have an LOI value of 25 or more according to JIS K7201-2 (2007).

High temperature shrinkage

In the present invention, the high-temperature shrinkage ratio is a value obtained by the following method: the fibers as the raw material of the nonwoven fabric were left to stand in a standard state (20 ℃ C., relative humidity 65%) for 12 hours, then applied with a tension of 0.1cN/dtex, the original length L0 was measured, the fibers were exposed to a dry heat atmosphere at 290 ℃ for 30 minutes without applying a load, and after sufficient cooling in the standard state (20 ℃ C., relative humidity 65%), further applied with a tension of 0.1cN/dtex to measure the length L1, which was determined from L0 and L1 by the following formula.

High temperature shrinkage rate [ ((L0-L1)/L0) ] X100 (%)

When the flame is brought close to the fiber and heat is applied, the thermoplastic fibers melt, and the molten thermoplastic fibers spread in a thin film along the surface of the non-molten fibers (aggregates). When the temperature is further increased, the two fibers are carbonized for a long time, but since the high-temperature shrinkage rate of the non-molten fibers is 3% or less, the vicinity of the portion contacting the flame at a high temperature is less likely to be shrunk, and the nonwoven fabric is less likely to be broken by the thermal stress generated between the low-temperature portion and the high-temperature portion not contacting the flame, so that the flame can be blocked for a long time. This can realize excellent flame retardancy as synthetic leather. From this point of view, the high-temperature shrinkage rate is preferably low, but the high-temperature shrinkage rate is preferably-5% or more because the non-woven fabric is broken by thermal stress due to large expansion under heat even though the non-woven fabric is not shrunk. Wherein the high-temperature shrinkage rate is preferably 0-2%.

Thermal conductivity

The thermal conductivity is a numerical expression of ease of heat conduction, and a small thermal conductivity means that the temperature rise of an unheated portion is small when the material is heated from one surface. For a unit area weight of 200g/m²The thickness was 2mm (density: 100 kg/m) as measured by a method according to JIS L1913(2010)³) The felt of (a) as a test piece, which is made of a material having a thermal conductivity of 0.060W/m · K or less as measured by a method according to ISO22007-3 (2008), is not easy to conduct heat, and when a nonwoven fabric is formed and heated from one surface, it is possible to suppress a temperature rise in the non-heated opposite side, and even if a combustible is arranged on the opposite side, the possibility of ignition of the combustible is reduced. Therefore, in the case of coating an article with the synthetic leather of the present invention, the flame retardancy of the coated article can be maintained. The lower limit of the fiber material that is easily available, though having a low thermal conductivity, is about 0.020W/mK.

LOI value

The LOI value is a volume percentage of the minimum amount of oxygen required for maintaining combustion of a substance in a mixed gas of nitrogen and oxygen, and it can be said that the higher the LOI value is, the more difficult the combustion is. Therefore, a thermoplastic fiber having an LOI value of 25 or more according to JIS K7201-2 (2007) is not easily combustible, and even if a fire occurs, if the fiber is separated from a fire source, the fiber is immediately extinguished, and a carbonized film is formed in a portion where the fire is usually slightly spread, and this carbonized portion can prevent ignition. The LOI value is preferably high, but the upper limit of the LOI value of a substance that can be obtained in reality is about 65.

Temperature of ignition

The ignition temperature is an autoignition temperature measured by a method based on JIS K7193 (2010).

Melting Point

The melting point is a value determined by a method based on JIS K7121 (2012). This means the value of the melting peak temperature when heating is performed at 10 ℃/min.

Non-melt fiber A

In the present invention, the non-molten fiber a means a fiber that does not liquefy while retaining its shape when exposed to flame, preferably a fiber that does not liquefy and ignite at a temperature of 800 ℃, and more preferably a fiber that does not liquefy and ignite at a temperature of 1000 ℃. Examples of the non-molten fibers having the high-temperature shrinkage ratio within the range defined in the present invention include flame-resistant fibers, meta-aramid fibers, and glass fibers.

The flame-resistant fiber is obtained by performing flame-resistant treatment on a fiber selected from acrylic fibers, pitch fibers, cellulose fibers, phenol fibers and the like. These may be used alone, or 2 or more of them may be used simultaneously. Among them, flame-resistant fibers which have a low high-temperature shrinkage ratio and are carbonized due to an oxygen barrier effect caused by a coating film formed when the thermoplastic fiber B described later comes into contact with a flame, and which further improve heat resistance at high temperatures, among various flame-resistant fibers, acrylonitrile-based flame-resistant fibers which are small in specific gravity, flexible, and excellent in flame resistance are more preferably used, and these flame-resistant fibers can be obtained by heating and oxidizing acrylic fibers as a precursor in high-temperature air. Examples of commercially available products include flame-retardant fiber PYRON (us registered trademark) manufactured by Zoltek company, which is used in examples and comparative examples described later, and Toho Tenax co. In addition, the meta-aramid fiber generally has a high-temperature shrinkage rate and does not satisfy the high-temperature shrinkage rate specified in the present invention, but can be preferably used if the meta-aramid fiber has a high-temperature shrinkage rate within the range of the present invention by suppressing the high-temperature shrinkage rate.

The non-melt fibers preferably used in the present invention may be used alone or in combination with different materials, and the fiber length is preferably in the range of 30 to 120mm, more preferably 38 to 70 mm. If the fiber length is within the range of 38 to 70mm, a nonwoven fabric can be produced by a usual needle punching method or a water interlacing method, and can be easily combined with different raw materials.

The thickness of the single fibers of the non-melt fibers is not particularly limited, but the single fiber fineness is preferably in the range of 0.1 to 10dtex in view of the passability in the carding step.

If the content of the non-molten fibers in the nonwoven fabric is too low, the function as an aggregate becomes insufficient, and therefore, the mixing ratio of the non-molten fibers a in the nonwoven fabric is preferably 15 mass% or more, and more preferably 20 mass% or more. The upper limit is preferably 80 mass% or less, and more preferably 70 mass% or less, from the viewpoint of productivity of the nonwoven fabric and strength of the nonwoven fabric.

Thermoplastic fiber B

The thermoplastic fiber B used in the present invention is a fiber having an LOI value within the range defined in the present invention and melting point at a melting point equal to or lower than the ignition temperature of the non-molten fiber a, and specific examples thereof include fibers made of a thermoplastic resin selected from the group consisting of flame-retardant liquid crystal polyester, flame-retardant poly (alkylene terephthalate), flame-retardant poly (acrylonitrile-butadiene-styrene), flame-retardant polysulfone, poly (ether-ketone), poly (ether-ketone), polyether sulfone, polyarylate, polyarylene sulfide, polyphenylene sulfone, polyether imide, polyamide imide and a mixture thereof. They may be used alone or in combination of 2 or more. When the LOI value is within the range specified in the present invention, the combustion in the air is easily suppressed, and the polymer is easily carbonized. Further, since the melting point (the temperature at which the fibers melt without the melting point) is lower than the ignition temperature of the non-molten fibers a, the molten polymer forms a coating film on the surface of the non-molten fibers a and between the fibers, and further, the carbonized polymer has a high oxygen blocking effect, whereby the oxidative degradation of the non-molten fibers a can be suppressed, and since the carbonized polymer exhibits excellent flame blocking property, the flame retardancy of the entire coated article coated with the synthetic leather of the present invention can be maintained when the synthetic leather is used as a synthetic leather base material. In addition, the melted polymer is carbonized by forming a film of the skin resin of the synthetic leather softened by heating together with the adhesive, thereby suppressing the burning of the surface of the synthetic leather.

The melting point (the temperature at which the thermoplastic fiber B melts without melting point) of the thermoplastic fiber B is preferably 200 ℃ or higher, more preferably 300 ℃ or higher lower than the ignition temperature of the non-molten fiber a. Among these, polyphenylene sulfide fibers (hereinafter, also referred to as PPS fibers) are most preferable from the viewpoint of the height of the LOI value, the range of the melting point, and the easiness of obtaining. Even if the polymer has an LOI value out of the range defined in the present invention, it is preferably used if the LOI value after the treatment is within the range defined in the present invention by treating the polymer with a flame retardant.

PPS is most preferred because it can exhibit the following mechanism: sulfuric acid is generated upon thermal decomposition of the polymer or the flame retardant due to the inclusion of sulfur atoms in the polymer structure or the flame retardant, and the polymer substrate is dehydrated and carbonized; when a flame retardant is used, a sulfur-based flame retardant is preferable. As the thermoplastic fiber B, a fiber containing 15 mass% or more of sulfur atoms is preferably used. Specifically, PPS and a polyester having a sulfur-based flame retardant are exemplified. The upper limit is preferably 50 mass% or less from the viewpoint of fiber strength.

The sulfur atom ratio referred to herein is determined by subjecting a sample (about 10mg) to temperature increase under air flow conditions from room temperature to 800 ℃ at 10 ℃/min to oxidative decomposition of thermoplastic fibers using a thermogravimetric analyzer, and quantitatively analyzing sulfur oxides in the decomposition gas by gas chromatography.

The thermoplastic fiber B used in the present invention is preferably one in which the thermoplastic resin is used alone or in combination with a different material, and the fiber length is preferably in the range of 30 to 120mm, more preferably 38 to 70 mm. If the fiber length is within the range of 38-70 mm, the non-woven fabric can be prepared by a common needle punching method and a water flow interweaving method, and can be easily compounded with different raw materials.

The thickness of the single fibers of the thermoplastic fibers B is not particularly limited, but the single fiber fineness is preferably in the range of 0.1 to 10dtex from the viewpoint of the passability in the carding step.

The PPS fiber preferably used in the present invention is composed of polymer structural units represented by formula- (C)₆H₄-S) -synthetic fibers formed of polymers which are the main structural unit. Representative examples of the PPS polymer include polyphenylene sulfide, polyphenylene sulfide sulfone, polyphenylene sulfide ketone, random copolymers and block copolymers thereof, and mixtures thereof. The PPS polymer particularly preferably contains- (C) preferably in an amount of 90 mol% or more based on the total weight of the PPS polymer₆H₄Polyphenylene sulfide in which the p-phenylene unit represented by-S) -is the main structural unit of the polymer. From the viewpoint of mass, polyphenylene sulfide containing 80 mass% and further containing 90 mass% or more of p-phenylene unit is preferable.

The PPS fiber preferably used in the present invention may be used alone or in combination with a different raw material, or may be in the form of any of filaments and short filaments (tapes). In the case of using the spun yarn, the fiber length is preferably in the range of 30 to 120mm, more preferably 38 to 70 mm. If the fiber length is within the range of 38-70 mm, the non-woven fabric can be prepared by a common needle punching method and a water flow interweaving method, and can be easily compounded with different raw materials. The thickness of the PPS filaments is not particularly limited, but the fineness of the filaments is preferably in the range of 0.1 to 10dtex from the viewpoint of the passability in the carding step.

The method for producing the PPS fiber used in the present invention is preferably as follows: a method of melting the polymer having a Phenylene sulfide (Phenylene sulfide) structural unit at a temperature higher than the melting point thereof and spinning the polymer from a spinneret to form a fiber. The spun fiber is an undrawn PPS fiber as it is. Most of the undrawn PPS fibers have an amorphous structure, and the elongation at break thereof is high. On the other hand, since such fibers lack dimensional stability against heat, drawn yarns are commercially available in which the fibers are oriented by hot drawing after spinning to improve the strength and thermal dimensional stability of the fibers. PPS fibers are distributed in the market in many products such as "Torcon" (registered trademark) (manufactured by dongli) and "Procon" (registered trademark) (manufactured by donghai textile).

In the present invention, the undrawn PPS fiber and the drawn yarn may be used in combination within a range satisfying the scope of the present invention. It is needless to say that instead of the PPS fiber, a drawn yarn and an undrawn yarn using a fiber satisfying the scope of the present invention may be used.

If the mixing ratio of the thermoplastic fibers B in the nonwoven fabric to be the fiber base layer of the synthetic leather is too low, the thermoplastic fibers cannot be spread into a sufficient film shape between the non-molten fibers of the aggregate, and therefore the mixing ratio of the thermoplastic fibers B in the nonwoven fabric is preferably 10 mass% or more, and more preferably 20 mass% or more. If the mixing ratio of the thermoplastic fibers B is too high, the carbonized part tends to become brittle when exposed to flame, and the fiber base layer part tends to open pores, so that the upper limit is preferably 85 mass% or less, and more preferably 80 mass% or less.

Fibers C other than the non-melt fibers A and the thermoplastic fibers B

In order to further impart specific properties to the nonwoven fabric which is a fibrous base layer of the synthetic leather, fibers C other than the non-melt fibers a and the thermoplastic fibers B may be contained. For example, vinylon fibers, modified polyester fibers, nylon fibers, or the like can be used to improve the wettability of the nonwoven fabric. By changing the wettability, the penetration depth of the fiber base material layer into the resin layer in the process of producing synthetic leather described later can be changed. The mixing ratio of the fibers C is not particularly limited within a range not impairing the effects of the present invention, and the mixing ratio of the fibers C other than the non-molten fibers a and the thermoplastic fibers B is preferably 20 mass% or less, more preferably 15 mass% or less. The lower limit of the use of the fiber C is not particularly limited as long as the desired performance is imparted thereto, and is usually preferably about 10 mass%.

Fibrous substrate layer constituting synthetic leather

The nonwoven fabric constituting the fibrous substrate layer of the synthetic leather of the present invention preferably has a basis weight of 50g/m²Above, more preferably 100g/m²Above, it is more preferably 150g/m²Above, and preferably 450g/m²Hereinafter, it is more preferably 400g/m²Hereinafter, it is more preferably 350g/m²The following. When the basis weight of the fiber base layer is within the above range, a light synthetic leather for aircraft sheet skin having excellent mechanical properties can be obtained.

The thickness of the nonwoven fabric of the fibrous base material layer is measured by a method according to JIS L-1913 (2010), and is preferably 0.4mm or more. If the thickness of the nonwoven fabric is too small, sufficient mechanical properties as a fiber base material layer cannot be obtained, sufficient flame retardancy cannot be obtained, and when a resin layer of synthetic leather is laminated, the resin layer or adhesive layer penetrates to the back side of the fiber base material layer, which deteriorates the quality of the synthetic leather. The upper limit of the thickness of the fibrous base material layer is not particularly limited, and is preferably set according to the quality and thickness of the synthetic leather.

The fibers used in the nonwoven fabric as the fibrous base layer of the present invention preferably have a crimp number of 7/2.54 cm or more, more preferably 12/2.54 cm or more, in order to sufficiently obtain the interlaminar properties between the fibers. The number of crimps in the present invention is a value measured in accordance with JIS L1015 (2000). The number of crimps is preferably measured in the state of raw cotton, and may be measured using a sample obtained by decomposing a fiber base material layer in the case where raw cotton is difficult to be used.

In order to obtain a more uniform nonwoven fabric, the staple fibers of the non-molten fibers a and the thermoplastic fibers B preferably have the same length. The same length does not have to be exactly the same, and there may be a difference of about ± 5% with respect to the length of the non-molten fiber a. From the above viewpoint, the fiber length is preferably within a range of 30 to 120mm, and more preferably within a range of 38 to 70mm, regardless of the fiber length of the non-molten fibers or the fiber length of the thermoplastic fibers B or C.

The nonwoven fabric of the fiber base layer of the synthetic leather of the present invention is produced by needle punching, water interlacing, or the like using the above-mentioned short fibers. The structure of the nonwoven fabric is not limited as long as it is within the range specified in the present invention, and the density of the nonwoven fabric is preferably more than 50kg/m³And less than 200kg/m³More preferably 55 to 180kg/m³More preferably 70 to 160kg/m³. When the density is too low, the skin resin layer or the adhesive layer excessively penetrates into the fiber base material layer when provided on the fiber base material layer, and the texture of the synthetic leather becomes too hard or the tear strength is reduced. On the other hand, when the density is too high, the fibrous base material layer itself becomes too hard, the texture of the synthetic leather becomes hard, or the fibrous base material layer becomes too dense, and therefore the adhesion to the resin layer or the adhesive layer is lowered. The density was calculated by dividing the mass of a sample at 30cm square by the thickness measured by the method based on JIS L1913 (2010).

The obtained nonwoven fabric may be heat-set by using a tenter or may be subjected to calendering. Of course, the raw fabric may be used as it is. The setting temperature may be a temperature at which the effect of suppressing the high-temperature shrinkage rate can be obtained, and is preferably 160 to 240 ℃, and more preferably 190 to 230 ℃. Calendering is a method of adjusting the thickness, i.e., the density, of a nonwoven fabric. Therefore, the density is too low, and when the skin resin layer or the adhesive layer is provided on the fiber base material layer, the density penetrates into the fiber base material layer too much, and the texture of the synthetic leather may be too hard, or the tear strength may be reduced. In this case, the calendering process may be performed before the skin resin layer or the adhesive layer is provided. If a nonwoven fabric having physical properties within the range specified in the present invention can be obtained, the speed, pressure and temperature of the calender are not limited.

Method for producing synthetic leather

The synthetic leather of the present invention is generally produced by forming a resin layer on a fibrous base layer. The method for forming the resin layer is not particularly limited, and examples thereof include: a method of forming a resin layer by applying a synthetic resin liquefied with a solvent and then drying the solvent; dry methods such as a method of applying a liquid resin and then reacting the resin; a lamination method of adhering a resin film formed of a synthetic resin; a wet method in which a liquid resin is applied and then introduced into a coagulation bath to be coagulated; and so on. Further, the surface of the synthetic leather is subjected to embossing or texturing as needed to obtain a desired appearance. The resin layer may have a 1-layer structure by using the above method alone, or may have a multilayer structure having 2 or more layers. When a multilayer structure having 2 or more layers is formed, the above-described methods may be combined to form each layer.

Resin layer

Examples of the synthetic resin forming the resin layer include a polyurethane resin, a polyamide resin, a polyacrylate resin, a vinyl acetate resin, a polyacrylonitrile resin, a polyvinyl acetate, an ethylene-vinyl acetate copolymer, SBR (styrene butadiene rubber), vinyl chloride, and vinylidene chloride. The synthetic resin can be used alone, also can use more than 2. Among these, polyurethane resins are suitable.

Specific components of the polyurethane resin include the following components: components commonly referred to as polyurethane resins, polyurethane urea resins; a component obtained by reacting an organic diisocyanate with a polyalkylene ether glycol having a molecular weight of 400 to 4000, or a polyester polyol having a hydroxyl group at the end, a poly-epsilon-caprolactone polyol, or a polycarbonate polyol, alone or in a mixture thereof, and chain-extending with a compound having 2 active hydrogens as necessary.

Examples of the polyalkylene ether glycol include: polytetramethylene ether glycol, polypropylene glycol, polyethylene glycol, glycerin propylene oxide adduct, polyether polyol obtained by adding ethylene oxide to a terminal thereof, and vinyl monomer-grafted polyether polyol. Examples of the polyester polyol include those obtained by reacting an alkylene glycol such as ethylene glycol, butanediol, hexanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, or the like with a carboxylic acid such as succinic acid, glutaric acid, adipic acid, sebacic acid, maleic acid, fumaric acid, phthalic acid, trimellitic acid, or the like so that the terminal thereof is a hydroxy acid. Examples of the polycarbonate polyol include polyethylene carbonate glycol, polytetramethylene carbonate glycol, and polyhexamethylene carbonate glycol.

Examples of the organic diisocyanate include aromatic isocyanates such as 2, 4-and 2, 6-tolylene diisocyanate, 4' -diphenylmethane diisocyanate, 1, 5-naphthalene diisocyanate, and xylylene diisocyanate; aliphatic isocyanates such as 1, 6-hexamethylene diisocyanate, dicyclohexylmethane-4, 4 '-diisocyanate, 3-isocyanatomethyl-3, 5, 5' -trimethylcyclohexyl isocyanate and 2, 6-diisocyanatomethylhexanoate, and these may be used alone or in combination of 2 or more.

The chain extender may be hydrazine, ethylenediamine, tetramethylenediamine, water, piperazine, isophoronediamine, ethylene glycol, butanediol, hexanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, or a glycol or diamine having improved hydrophilicity, such as dimethylolpropionic acid or an adduct of ethylene oxide with aminoethanesulfonic acid.

As the polyurethane resin, a polycarbonate-based polyurethane resin containing a polycarbonate polyol as a constituent component is preferably used in view of excellent hydrolysis resistance. In addition, in particular, in the resin layer present on the outermost surface of the synthetic leather, it is preferable to use a polycarbonate-based polyurethane resin modified with silicone in order to improve the texture of the synthetic leather.

The silicone-modified polycarbonate polyurethane is a polycarbonate polyurethane having an organopolysiloxane skeleton in the molecular chain or an organopolysiloxane skeleton blocked at the molecular chain end by a functional group that is unreactive to an isocyanate group (e.g., trialkylsilyl group, triarylsilyl group, etc.).

Adhesive layer

When a resin layer is laminated in the lamination method, an adhesive is used for adhering the resin film. As the adhesive, an ethylene-vinyl acetate copolymer emulsion, a polyvinyl chloride paste, a polyurethane adhesive, an epoxy adhesive, or the like can be used. Among them, a polyurethane adhesive is preferably used in view of adhesion to the resin layer and prevention of excessive hardening due to the adhesive.

The urethane resin constituting the adhesive may be a polyester, polyether, polycarbonate or the like, or a mixture thereof, and for example, a polyurethane resin having an average molecular weight of about 500 to 2500 obtained from a polymer diol (for example, at least 1 diol selected from polyester diol, polyether diol, polyester-ether diol, polycaprolactone diol, polycarbonate diol and the like) and an organic polyisocyanate (for example, at least 1 or more organic polyisocyanates selected from aromatic diisocyanate, aromatic triisocyanate, alicyclic diisocyanate and the like) and having an average molecular weight of about 10000 to 40000 is available, and a polyurethane resin commercially available as a solution containing 40 to 70 mass% of a solid component is available. Particularly preferred is a polyester-based urethane resin. The 100% modulus of a cured product of the adhesive measured in accordance with JIS K-6251 (2017) is 0.5 to 5MPa, and in particular, 0.5 to 3MPa is preferable in view of the bending resistance.

The adhesive may be applied to the surface of the fiber base material or to the surface of the resin sheet. There are a wet laminating adhesive for bonding the fiber base layer and the skin resin layer without drying the solvent and a dry laminating adhesive for bonding the fiber base layer and the skin resin layer after drying the solvent, and any of them may be used in order to reduce the process load and improve the physical properties of the synthetic leather.

Flame retardants and other additives

In the present invention, the resin layer or the adhesive layer, or both layers may contain a flame retardant in order to further improve flame retardancy. The flame retardant to be used is not particularly limited, and specific examples thereof include inorganic flame retardants such as aluminum hydroxide, titanium oxide, zinc oxide, expandable graphite, magnesium hydroxide, calcium carbonate, zinc borate, ammonium polyphosphate, aluminum diethylphosphinate, and red phosphorus; organic flame retardants such as polyphosphoric acid, melamine cyanurate, phosphate ester compounds, and phosphate amide compounds may be used in a mixture of 1 or 2 or more.

Examples of the phosphate ester-based compound include trioctyl phosphate, triphenyl phosphate, tricresyl phosphate, tris (xylene) phosphate, tolyldiphenyl phosphate, tolylbis (2, 6-xylenyl phosphate), isopropylphenyl phosphate, tert-butylphenyl phosphate, biphenyldiphenyl phosphate, naphthyldiphenyl phosphate, resorcinolbis (diphenyl phosphate), resorcinolbis (xylenyl phosphate), bisphenol a bis (diphenyl phosphate), tris (chloropropyl) phosphate, tris (dichloropropyl) phosphate, tris (tribromoneopentyl) phosphate, and the like.

Among the above flame retardants, substances that promote carbonization, such as phosphate ester compounds, phosphate amide compounds, and aluminum diethylphosphinate, are preferred from the viewpoint of synergistic effect with carbonization of the fiber base layer.

The content of the flame retardant in the resin layer or the adhesive layer, or both is preferably 1 to 300 parts by mass, more preferably 5 to 250 parts by mass, and still more preferably 10 to 200 parts by mass, based on 100 parts by mass of the solid component in the resin layer or the adhesive layer. Even if the resin layer or the adhesive layer, or both, contain no flame retardant at all, the flame retardant performance of the synthetic leather as a whole is excellent due to the excellent flame retardant performance of the fibrous base layer, and the flame retardant performance of the synthetic leather is further improved by containing the flame retardant in the above range in the resin layer or the adhesive layer, or both. On the other hand, if the content of the flame retardant in the resin layer or the adhesive layer, or both, is too large, problems such as appearance change such as hardening and wrinkling, reduction in light resistance, and delamination of the synthetic leather due to reduction in adhesive strength of the adhesive may occur. The term "wrinkle formation" as used herein refers to an appearance defect that appears to be mottled when droplets of water, alcohol, or the like are dropped and dried, and for example, when water is attached to synthetic leather containing a flame retardant, the flame retardant is dissolved in the attached water to some extent and then dried, and the mottled portion is formed.

The synthetic leather of the present invention may further contain various additives such as an antibacterial/insect-repellent agent, an antistatic agent, a slip agent, a light resistance improver, a heat resistance improver, an ultraviolet absorber, an antioxidant, a water repellent, a crosslinking agent, a plasticizer, a coloring agent, and an antifoaming agent, if necessary; surfactants such as dispersants and penetrants, and stabilizers such as tackifiers; fillers such as clay, talc, mica, expandable graphite, wollastonite, kaolin, montmorillonite, bentonite, sepiolite, xonotlite and silica may also be added.

Weight per unit area and thickness of synthetic leather and resin layer

The thickness of the synthetic leather is preferably 0.5 to 4.0mm, more preferably 0.7 to 3.5mm, and even more preferably 0.9 to 3.0mm, from the viewpoint of space saving when used as a coating material such as a flame retardant, abrasion durability, texture, and sheet. When the thickness is smaller than the above range, abrasion durability is insufficient, and flame retardancy of the entire coated article such as a sheet material when the coated article is integrated with an article such as a seat cushion is deteriorated. On the other hand, when the thickness is larger than the above range, the texture becomes hard.

The synthetic leather preferably has a weight per unit area of 150 to 1000g/m from the viewpoint of flame retardancy, abrasion durability, texture, and weight reduction of a coated article such as a sheet²More preferably 170 to 800g/m²More preferably 200 to 600g/m². When the weight per unit area is less than the above range, abrasion durability is insufficient, and flame retardancy of the entire coated article such as a sheet material when the coated article is integrated with an article such as a seat cushion is deteriorated. On the other hand, when the weight per unit area is larger than the above range, the sheet as a whole becomes too heavy, and the advantage of weight reduction cannot be obtained.

In the synthetic leather of the present invention, the mass ratio of the fibrous base material layer to the mass of the entire synthetic leather is preferably 20 mass% or more, more preferably 30 mass% or more, and still more preferably 40 mass% or more. In the fiber base material layer constituting the synthetic leather of the present invention, in order to exhibit excellent flame retardancy by the fiber base material layer alone, when the mass ratio of the fiber base material layer is less than the above range, there is a possibility that the flame retardancy may be lowered when the synthetic leather alone or the fiber base material layer is formed into a coated article such as a sheet. On the other hand, the upper limit of the mass ratio of the fibrous base material layer is not particularly limited, but is preferably 80 mass% or less, more preferably 75 mass% or less, and further preferably 70 mass% or less, from the viewpoint of achieving the surface feel and functionality as the synthetic leather.

When the resin layer is laminated on the fiber base material layer by the dry method or the wet method, the resin layer is directly applied or transferred to the fiber base material layer, and therefore the resin layer directly penetrates into the fiber base material layer. On the other hand, when the resin layer is laminated by a lamination method, the resin layer is formed on the release paper or the release film and laminated with the fiber base material layer via the adhesive, and therefore the adhesive layer penetrates into the fiber base material layer. The depth of penetration of the resin layer or the adhesive layer into the fibrous base material layer in the thickness direction of the synthetic leather affects the interlaminar peel strength between the fibrous base material layer and the resin layer of the synthetic leather and the texture of the synthetic leather. From the viewpoint of satisfying both the texture of the synthetic leather and the interlayer peel strength between the fiber base material layer and the resin layer, the penetration depth of the resin layer or the adhesive layer into the fiber base material layer is preferably 0.05 to 0.40mm, more preferably 0.07 to 0.38mm, and still more preferably 0.10 to 0.35 mm. When the penetration depth of the resin layer or the adhesive layer into the fiber base material layer is not less than the lower limit of the above range, the synthetic leather is excellent in abrasion durability and interlayer peel strength between the fiber base material layer and the resin layer. On the other hand, when the penetration depth of the resin layer or the adhesive layer into the fiber base material layer is not more than the upper limit of the above range, the texture is particularly excellent without being hardened. In order to set the penetration depth of the resin layer or the adhesive layer in the fiber base material layer within the above range, the molecular weight of the substance described in the "resin layer" or the "adhesive layer" and the concentration diluted with the solvent may be appropriately adjusted, the temperature and speed of drying the solvent may be appropriately adjusted in the case of the dry method, the temperature of the coagulation bath and the concentration of the poor solvent may be appropriately adjusted in the case of the wet method, and the temperature and pressure at the time of lamination may be appropriately adjusted in the case of the lamination method.

Use of synthetic leather

The synthetic leather of the present invention thus obtained has excellent flame retardancy and also has excellent physical properties such as texture and peel strength, and its flame retardancy exerts an effect on the whole of a coated article when the synthetic leather alone is coated on an article such as cushion foam. Therefore, the sheet can be used as a surface finishing material for covering a seat cushion material or the like, in addition to direct use such as ceiling or wall surface decoration. Among them, the surface finishing material is particularly preferably used for coating a seat cushion material which is required to have high flame retardancy and is mounted on automobiles, railways, and ships; surface decorative materials such as chairs and sofas in high-rise buildings and public facilities.

Examples

Next, the present invention will be specifically described based on examples. However, the present invention is not limited to these examples. Various modifications and corrections can be made within the scope not exceeding the technical scope of the present invention. The measurement methods of various characteristics used in the present example are as follows.

[ weight per unit area of fiber base Material layer ]

The mass of a 30cm square sample was measured at 1m intervals²Mass (g/m) of²) And (4) showing. In the case where the measurement sample is a synthetic leather, when it is difficult to perform measurement using the fiber base layer alone, the following values may be used: the basis weight of the fiber base material layer was calculated by using a synthetic leather sample having an arbitrary area, peeling off the resin layer, and dividing the mass of the fiber base material portion by the area of the sample.

[ weight per unit area of synthetic leather ]

The mass of a 30cm square sample was measured at 1m intervals²Mass (g/m) of²) And (4) showing. When the measurement sample is less than 30cm square, a value calculated by dividing the mass of the sample by the area of the sample can be used.

[ weight per unit area of resin layer/adhesive layer ]

The above-mentioned [ weight per unit area of synthetic leather ]]And [ weight per unit area of fibrous substrate layer]Mass difference (g/m)²)。

[ Mass ratio of the fibrous base material layer to the entire synthetic leather ]

The ratio (%) is obtained by dividing the [ weight per unit area of the fibrous base material layer ] by the [ weight per unit area of the synthetic leather ].

[ thickness of fiber base Material layer ]

The thickness of the fibrous base material layer was measured in accordance with JIS L-1913 (2010). In the case where the measurement sample is a synthetic leather, when it is difficult to perform measurement using the fiber base layer alone, the following setting may be made: in a cross section of the sample, the entire synthetic leather in the thickness direction thereof is imaged at a magnification of about 50 to 90% (specifically, about 30 to 200 times) of an imaging range of a Scanning Electron Microscope (SEM), and the thickness of the fiber base layer portion is read in a scale at arbitrary 5 places in a cross-sectional photograph, and the average value thereof is taken as the thickness of the fiber base layer.

[ thickness of synthetic leather ]

The thickness of the synthetic leather was measured according to JIS L-1913 (2010).

[ penetration depth of the resin layer or adhesive layer into the fibrous base material layer in the thickness direction of the synthetic leather ]

In the cross section of the synthetic leather, the image is taken with a magnification (specifically, about 30 to 100 times) that the whole of the thickness direction reaches 50 to 90% of the image pickup range of the SEM and that the interface between the resin layer and the fiber base material layer can be clearly observed, and the depth of penetration of the resin layer or the adhesive layer into the fiber base material layer is read at 20 points at a constant interval in the width direction of the cross-sectional photograph by scale, and the average value thereof is the penetration depth of the resin layer or the adhesive layer into the fiber base material layer in the thickness direction of the synthetic leather. When the thickness of the synthetic leather is too small and the observation magnification is too large, the same measurement is performed by moving the observation field, and the measurement is performed by at least 1mm continuously in the longitudinal direction of the sample, and the average value of the penetration depth at all the sites is used. Fig. 2 is a photograph showing a cross section of the synthetic leather, wherein 8 in the drawing indicates an interface of the fiber base material layer in a state where the resin layer is laminated, 9 in the drawing indicates an interface of the penetrated resin layer, and a penetration depth of the resin layer or the adhesive layer in the fiber base material layer in a thickness direction of the synthetic leather indicates a distance between 8 and 9 in the drawing.

[ tensile Strength of synthetic leather ]

Based on ASTM D-751(2011), a sample (obtained by cutting a sample into a width of 25.4mm (1 inch)) was stretched at a chuck-to-chuck distance of 152mm and a stretching speed of 152 mm/min, and the maximum load until the sample broke was divided by the sample width, and the breaking load per 25.4mm (1 inch) was defined as the tensile strength (N/25.4 mm). The measurement was performed with N ═ 3, and the average value thereof is shown.

[ tensile elongation of synthetic leather ]

The following elongations were set: the tensile elongation of the synthetic leather was determined by dividing the elongation of the sample at the time point of breaking when the sample (obtained by cutting the sample into 100mm width) was stretched at a distance between chucks of 152mm and a stretching speed of 152 mm/min by the ratio (%) obtained by dividing the elongation of the sample by the test length of the sample of 152mm, based on ASTM D-751 (2011). The measurement was performed with N ═ 3, and the average value thereof is shown.

[ tear Strength of synthetic leather ]

Tear strength (N) was determined by the gradient (trapezoid) method based on ASTM D-5733(1999), shown as the average of N-3.

[ peeling Strength of synthetic leather ]

The resin layer at one end of a sample having a width of 25.4mm (1 inch) was peeled from the fiber base material layer and set in a chuck in accordance with ASTM D-903 (2017). In this state, the resin layer and the fiber base material layer were peeled at a speed of 300 mm/min in the direction of 180 degrees. The average value of the peel load of 127mm (5 inches) from the position 25.4mm (1 inch) from the start of peeling to the position 152.4mm (6 inches) was divided by the sample width, and the peel load (N/25.4mm) per 25.4mm (1 inch) was defined as the peel strength. The measurement was performed with N ═ 3, and the average value thereof is shown.

[ abrasion durability of synthetic leather ]

A westernberber (Wyzenbeek) abrasion test was performed based on ASTM D-4157(2017) under conditions of a load of 1361gf (3Lb) (13.3N) and a tension of 1814gf (4Lb) (17.8N) using a No. 10 canvas as a rubbing cloth and N ═ 3. After 3000 cycles of abrasion, the surface of the synthetic leather was not damaged and the resin layer was peeled off, and the result was regarded as a pass (a). The case where damage or peeling of the resin layer was observed was regarded as a failure (denoted by F).

[ seam Strength of synthetic leather ]

2 synthetic leathers were sewn on the basis of the seam strength mapping method of ASTM D-751(2011), and the breaking strength of the seam portion when the seam was stretched in the direction of 180 degrees was divided by the sample width and expressed as N/25.4 mm. The test was carried out with N ═ 3, and the average value thereof is shown.

[ flame retardancy test for synthetic leather for automobile interior Material ]

Based on a horizontal combustion test fmvssno.302 for an automobile interior material specified in JIS D1201 (1998), a combustion speed of 4 inches (102 mm)/minute or less is defined as a pass, a combustion speed of 4 inches (102 mm)/minute or less is defined as B, a combustion speed of 3 inches (76 mm)/minute or less is defined as a, and a fail is defined as F.

[ flame-retardant test of synthetic leather for interior Material of aircraft ]

In the 12-second vertical burning test specified in 14CFR Part25 section25.853(a) and Appendix Fto Part25, Part i, a pass (a) was set to a burn duration of 15 seconds or less, a dripping burning time of 5 seconds or less, and a burn length of 203mm (8 inches), and a fail (F) was set to the other.

[ flame-retardant test of cushioning Material for aircraft seat ]

The combustion test was performed based on the gasoline burner (gasoline burner) test specified in 14CFR Part25 section25.853(c) Appendix F Part25, Part II. Fig. 1 is an explanatory view for explaining a method of assembling a coated article for evaluating flame retardancy of the coated article used in a combustion test of an aircraft seat cushion material, and the combustion test. A soft urethane foam commercially available from Fuji rubber industries, Inc. was cut into a size of 450 mm. times.500 mm for a seat surface and 450 mm. times.630 mm for a back surface, and the size was set as a urethane foam (seat surface) 1 and a urethane foam (back surface) 2, respectively. The following skin material (seat surface) 4 and skin material (back surface) 5 were prepared: the synthetic leather of the present invention is attached with a "Velcro (registered trademark)" fastening tape 3 made of polyphenylene sulfide by sewing meta-aramid yarn. The cover material (seat surface) 4 and the cover material (back surface) 5 are respectively covered with a urethane foam (seat surface) 1 and a urethane foam (back surface) 2, and are fixed to an L-shaped frame (not shown), and a covered article 7 is assembled. The mass of the sample before the test was measured in advance. The sample was heated for 2 minutes by a burner 6 from the side of the sample, and the temperature of the burner was set in the range of 1000. + -. 20 ℃ from the lowest temperature and the highest temperature measured at 5 points in the width direction at the root of the burner port. After heating, the burner was removed from the sample and left for 5 minutes. The sample mass was measured after 5 minutes of standing. The test piece was evaluated as passed when the flame of the sample after leaving for 5 minutes had completely extinguished, the burning lengths of the front and rear sides of the back cushion material and the bottom and upper portions of the seat cushion material were all 432mm (17 inches) or less, and the reduction rate of the sample mass after the test was 10.0% or less; wherein A represents a mass reduction rate of 5.0% or less, and B represents a mass reduction rate of more than 5.0% and 10.0% or less. The test piece was evaluated as "failed", i.e., F, which was a test piece that had ignited after being left for 5 minutes and had not extinguished the flame, but had a burning length of more than 432mm (17 inches), or had a mass reduction rate of more than 10.0%.

[ sensory evaluation of the texture of a cushion Material coated with synthetic leather ]

In the same manner as the above-mentioned sample of [ flame retardant test for aircraft seat cushion ], a surface-decorated sample was prepared by coating the synthetic leather of the present invention with a urethane cushion. Please 5 people evaluated the hand feel and seat comfort of the samples on a 5-level scale (1: hard, poor seat comfort-5: soft, good seat comfort), showing their average scores.

[ fibers constituting the fiber base Material layer ]

< non-melting fiber A >

1.7dtex flame-retardant fiber "PYRON" (U.S. registered trademark) manufactured by Zoltek corporation, length 51mm, high-temperature shrinkage rate 1.6%, and thermal conductivity 0.033W/m.K (manufactured to 200g/m²Needle felt with a thickness of 2mm and measured). The number of crimps was 12 (pieces/25 mm) and the crimp ratio was 12%.

The number of crimps and the crimp ratio are values measured according to JIS L1015 (2000).

< thermoplastic fiber B-1 >

A drawn PPS fiber having a single fiber fineness of 2.2dtex (diameter: 14 μm) and a cut length of 51mm was prepared in accordance with Torcon (registered trademark) model S371, manufactured by Toray corporation, having an LOI value of 34, a melting point of 284 ℃, a glass transition temperature of 90 ℃, a crimp number of 14 (piece/25 mm), and a crimp rate of 18%. The ratio of sulfur atoms in the fiber was 26.2 mass%.

< thermoplastic fiber B-2 >

As an undrawn PPS fiber having a single fiber fineness of 6.0dtex (diameter: 23 μm) and a cut length of 51mm, Torcon (registered trademark) model S311, manufactured by Toray corporation, LOI value: 34, melting point: 280 ℃, glass transition temperature: 90 ℃, crimp number: 16 (piece/25 mm), and crimp ratio: 22%. The ratio of sulfur atoms in the fiber was 26.1 mass%.

< other fibers C-1 >

A polyethylene terephthalate (PET) fiber having a single fiber fineness of 2.2dtex (diameter: 14 μm) and a cut length of 51mm, which was "Tetoron" (registered trademark) model T9615 manufactured by Toray corporation, had an LOI value of 22, a melting point of 256 ℃, a crimp number of 16 (pieces/25 mm), and a crimp ratio of 17%.

< other fibers C-2 >

"Arauin (Japanese: アラウィン)" (registered trademark) manufactured by Toray Chemical Korea Inc., having a single fiber fineness of 1.7dtex (diameter: 13 μm) and a cut length of 51mm, a LOI value of 26, a melting point of 428 ℃, a high-temperature shrinkage of 6.7%, a crimp number of 11 (piece/25 mm), and a crimp rate of 9%.

< other fibers C-3 >

A common commercially available rayon having a single fiber fineness of 2.2dtex (diameter: 14 μm) and a cut length of 51mm (flame retardant was not incorporated), an LOI value of 17, no melting point, a high-temperature shrinkage of 25.3%, a crimp number of 13 (piece/25 mm), and a crimp rate of 13%.

[ synthetic resin constituting the resin layer ]

< polyurethane resin D-1 >

A generally commercially available non-yellowing polycarbonate polyurethane having a 100% modulus of 2 to 10MPa is used.

< polyurethane resin D-2 >

A generally commercially available silicone-modified non-yellowing polycarbonate polyurethane having a 100% modulus of 5 to 10MPa is used.

[ adhesive agent constituting adhesive layer ]

A generally commercially available polycarbonate type polyurethane adhesive was used.

[ flame retardant ]

ペコフレーム STC (main component: aluminum diethylphosphinate) manufactured by Archroma Japan was used.

[ example 1]

(production of fibrous substrate layer)

The drawn PPS fibers and the flame-resistant fibers are mixed by a spreader, followed by further mixing by a mixer, and then passed from a carding machine to make a web. The obtained nets were laminated by a cross lapper, and then felted by a needle punch to obtain a nonwoven fabric formed of drawn yarns of PPS fibers and flame-resistant fibers. The mass mixing ratio of the drawn PPS fiber and the flame-retardant fiber of the non-woven fabric was 60:40, and the basis weight was 181g/m²The thickness was 1.51 mm.

(production of synthetic leather)

The nonwoven fabric obtained by the above method was used as a fiber base material layer, and was immersed in a polyvinyl alcohol aqueous solution having a polymerization degree of 500 and a saponification degree of 92%. The polyvinyl alcohol solid content was 12 parts by mass per 100 parts by mass of the fiber base material layer. Next, a solution containing 15 parts by mass of the flame retardant per 100 parts by mass of the polyurethane resin D-1 was prepared, and this was applied to the fiber base material layer with a knife coater. Washing the coated fiber substrate layer with 60 deg.C warm water, and replacing with the previously coated polyvinyl alcoholThereafter, the resultant was dried in an oven at 120 ℃ to obtain wet synthetic leather. The amount of adhesion of the polyurethane resin calculated from the mass of the sample after drying was 188g/m². Further, a comma coater was used so as to be 30g/m²The polyurethane resin D-2 dissolved in a solvent was applied to a release paper, and dried to prepare a film. About 20g/m of a mixture of 100 parts by mass of an adhesive and 15 parts by mass of a flame retardant²Coating on film, adhering to the wet synthetic leather, and aging. The synthetic leather laminated with the film had a weight per unit area of 415g/m²And the thickness is 1.32 mm. The penetration depth of the resin layer and the adhesive layer into the fibrous base layer was 0.29mm as calculated from the SEM photograph of the cross section of the obtained synthetic leather.

(evaluation of various physical Properties)

The mechanical properties and abrasion durability are shown in table 1, and the sufficient properties as synthetic leather are satisfied. Further, the flame retardant test for the automobile interior material showed good results of self-extinguishing within a 38mm mark, no after-burning nor dripping-burning in the flame retardant test for the aircraft interior material, and a burning length of 61mm in the longitudinal direction and 69mm in the lateral direction. The obtained synthetic leather was coated on a urethane cushion material, and a flame retardant test was performed on the seat cushion material, and as a result, the combustion length was also within the acceptable range, and the mass reduction rate was excellent and was 4.9%. The resulting cushioning material had soft and good texture.

[ example 2]

(production of fibrous substrate layer)

The unit area weight was changed to 231g/m²A nonwoven fabric was produced in the same manner as in example 1, except that the thickness was changed to 1.57 mm.

(production of synthetic leather)

The weight per unit area of the polyurethane resin D-1 and the flame retardant constituting the wet synthetic leather after drying was changed to 131g/m²The nonwoven fabric obtained by the above method was used as a fibrous base layer, and the synthetic leather laminated with the film had its weight per unit area changed to 413g/m²Synthetic leather was produced in the same manner as in example 1, except that the thickness was changed to 1.39mm. The penetration depth of the resin layer and the adhesive layer into the fibrous base layer was 0.21mm as calculated from the SEM photograph of the cross section of the obtained synthetic leather.

(evaluation of various physical Properties)

The mechanical properties and abrasion durability are shown in table 1, and the sufficient properties as synthetic leather are satisfied. Further, the flame retardant test for the automobile interior material showed good results of self-extinguishing within a 38mm mark, no after-burning nor dripping-burning in the flame retardant test for the aircraft interior material, and a burning length of 58mm in the longitudinal direction and 60mm in the transverse direction. The obtained synthetic leather was coated on a urethane cushion material, and a flame retardant test was performed on the seat cushion material, and as a result, the combustion length was also within the acceptable range, and the mass reduction rate was excellent and was 3.9%. The resulting cushioning material had soft and good texture.

[ example 3]

(production of fibrous substrate layer)

The mass ratio of the drawn PPS fiber to the flame-resistant fiber was changed to 90:10, and the unit area weight was 178g/m²A nonwoven fabric was produced in the same manner as in example 1, except that the thickness was 1.42 mm.

(production of synthetic leather)

The weight per unit area of the polyurethane resin D-1 and the flame retardant constituting the wet synthetic leather after drying was changed to 186g/m²The nonwoven fabric obtained by the above method was used as a fibrous base layer, and the synthetic leather laminated with the film had a weight per unit area changed to 409g/m²A synthetic leather was produced in the same manner as in example 1, except that the thickness was changed to 1.34 mm. The penetration depth of the resin layer and the adhesive layer into the fiber base layer was 0.19mm as calculated from the SEM photograph of the cross section of the obtained synthetic leather.

(evaluation of various physical Properties)

The mechanical properties and abrasion durability are shown in table 1, and the sufficient properties as synthetic leather are satisfied. Further, the flame-retardant test for the interior material of an automobile showed self-extinguishing within a 38mm mark, and the flame-retardant test for the interior material of an airplane showed neither afterflame nor dripping flame, and showed good results with a burning length of 120mm in the longitudinal direction and 110mm in the transverse direction. The obtained synthetic leather was coated on a urethane cushion material and subjected to a flame retardant test on a seat cushion material, and as a result, the combustion length was within a satisfactory range and the mass reduction rate was 9.5% within a satisfactory range. The resulting cushioning material had soft and good texture.

[ example 4]

(production of fibrous substrate layer)

The mass ratio of the drawn PPS fiber to the flame-resistant fiber was changed to 20:80, and the unit area weight was set to 171g/m²A nonwoven fabric was produced in the same manner as in example 1, except that the thickness was 1.59 mm.

(production of synthetic leather)

The weight per unit area after drying of the polyurethane resin D-1 and the flame retardant constituting the wet synthetic leather was changed to 178g/m²The nonwoven fabric obtained by the above method was used as a fibrous base layer, and the synthetic leather laminated with the film had its weight per unit area changed to 394g/m²A synthetic leather was produced in the same manner as in example 1, except that the thickness was changed to 1.43 mm. The penetration depth of the resin layer and the adhesive layer into the fiber base layer was 0.31mm as calculated from the SEM photograph of the cross section of the obtained synthetic leather.

(evaluation of various physical Properties)

The mechanical properties and abrasion durability are shown in table 1, and the sufficient properties as synthetic leather are satisfied. Further, the flame-retardant test for the interior material of an automobile showed self-extinguishing within a 38mm mark, and the flame-retardant test for the interior material of an airplane showed no afterflame nor dripping flame, and the flame length was 65mm in the longitudinal direction and 70mm in the transverse direction, which are good results. The obtained synthetic leather was coated on a urethane cushion material, and a flame retardant test was performed on the seat cushion material, and as a result, the combustion length was also within a qualified range, and the mass reduction rate was 8.1% within a qualified range. The resulting cushioning material had soft and good texture.

[ example 5]

(production of fibrous substrate layer)

Except for drawing PPS fiber and resistingUsing PET fibers in addition to the flame-retardant fibers, the mass ratios of the drawn PPS fibers to the flame-retardant fibers and to the PET fibers were changed to 30:40:40, respectively, and the basis weight was 179g/m²A nonwoven fabric was produced in the same manner as in example 1, except that the thickness was 1.49 mm.

(production of synthetic leather)

The weight per unit area of the polyurethane resin D-1 and the flame retardant constituting the wet synthetic leather after drying was changed to 176g/m²The nonwoven fabric obtained by the above method was used as a fibrous base layer, and the weight per unit area of the synthetic leather laminated with the film was changed to 401g/m²A synthetic leather was produced in the same manner as in example 1, except that the thickness was changed to 1.35 mm. The penetration depth of the resin layer and the adhesive layer into the fiber base layer was 0.35mm as calculated from the SEM photograph of the cross section of the obtained synthetic leather.

(evaluation of various physical Properties)

The mechanical properties and abrasion durability were as shown in table 2, and the physical properties sufficient as synthetic leather were satisfied. In addition, although the flame-retardant test for the automobile interior material burned beyond the 38mm mark, the combustion rate was 78 mm/min, which was within the acceptable range. In the flame retardant test facing the aircraft interior material, the afterflame is 1.2 seconds in the longitudinal direction and 1.5 seconds in the transverse direction, the dripping combustion is 0.5 second in the longitudinal direction and 1.0 second in the transverse direction, the combustion length is 109mm in the longitudinal direction and 119mm in the transverse direction, and the afterflame is in a qualified range. The obtained synthetic leather was coated on a urethane cushion material and subjected to a flame retardant test on a seat cushion material, and as a result, the combustion length was also within a satisfactory range, and the mass reduction rate was 9.9% within a satisfactory range. The resulting cushioning material had soft and good texture.

[ example 6]

(production of fibrous substrate layer)

The unit area weight was 82g/m²A nonwoven fabric was produced in the same manner as in example 1, except that the thickness was 0.83 mm.

(production of synthetic leather)

The polyurethane resin D-1 constituting the wet synthetic leather and the flame retardantThe weight per unit area after drying was changed to 299g/m²The nonwoven fabric obtained by the above method was used as a fibrous base layer, and the weight per unit area of the synthetic leather laminated with the film was changed to 430g/m²A synthetic leather was produced in the same manner as in example 1, except that the thickness was changed to 1.51 mm. The penetration depth of the resin layer and the adhesive layer into the fiber base layer was 0.33mm as calculated from the SEM photograph of the cross section of the obtained synthetic leather.

(evaluation of various physical Properties)

The mechanical properties and abrasion durability were as shown in table 2, and the physical properties sufficient as synthetic leather were satisfied. Further, although the flame-retardant test for the automobile interior material burned within a mark line of more than 38mm, the combustion rate was 26 mm/min, which is a good result. In the flame retardant test for the interior material of an aircraft, no afterflame nor dripping flame was observed, and good results were obtained with a flame length of 89mm in the longitudinal direction and 83mm in the transverse direction. The obtained synthetic leather was coated on a urethane cushion material and subjected to a flame retardant test on a seat cushion material, and as a result, the combustion length was also within a satisfactory range, and the mass reduction rate was 9.7% within a satisfactory range. The resulting cushioning material had soft and good texture.

[ example 7]

(production of fibrous substrate layer)

The PPS fiber was changed from a drawn PPS fiber to an undrawn PPS fiber, and the basis weight was 193g/m by the same procedure as in example 1²The nonwoven fabric of (3) was brought into contact with 2S-shaped iron rolls heated at 190 ℃ to densely form films of undrawn PPS fibers, thereby obtaining a fibrous substrate layer having a thickness of 1.01 mm.

(production of synthetic leather)

The weight per unit area after drying of the polyurethane resin D-1 and the flame retardant constituting the wet synthetic leather was changed to 190g/m²The synthetic leather laminated with the film using the nonwoven fabric obtained by the above method as a fibrous base layer was altered in the unit area weight to 429g/m²A synthetic leather was produced in the same manner as in example 1, except that the thickness was changed to 1.65 mm. Using the obtained section of synthetic leatherThe penetration depth of the resin layer and the adhesive layer into the fiber base material layer calculated from the surface SEM photograph was 0.04 mm.

(evaluation of various physical Properties)

As shown in Table 2, the peel strength was 1.3kgf (12.7N)/25.4mm in the machine direction and 1.5kgf (14.7N)/25.4mm in the transverse direction, but the mechanical properties and abrasion durability were satisfactory as synthetic leathers. Further, the flame-retardant test for the interior material of an automobile showed self-extinguishing within a 38mm mark, and the flame-retardant test for the interior material of an airplane showed neither afterflame nor dripping flame, and showed good results with a flame length of 69mm in the longitudinal direction and 64mm in the transverse direction. The obtained synthetic leather was coated on a urethane cushion material and subjected to a flame retardant test on a seat cushion material, and as a result, the combustion length was also within a satisfactory range, and the mass reduction rate was 5.1% within a satisfactory range. The resulting cushioning material had soft and good texture.

[ example 8]

(production of fibrous substrate layer)

The weight per unit area was 181g/m²A nonwoven fabric was produced in the same manner as in example 1, except that the thickness was 1.51 mm.

(production of synthetic leather)

The weight per unit area after drying of the polyurethane resin D-1 and the flame retardant constituting the wet synthetic leather was changed to 162g/m²The nonwoven fabric obtained by the above method was used as a fibrous base layer, and the weight per unit area of the synthetic leather laminated with the film was changed to 391g/m²A synthetic leather was produced in the same manner as in example 1, except that the thickness was changed to 1.29 mm. The penetration depth of the resin layer and the adhesive layer into the fibrous base material layer was calculated from the SEM photograph of the cross section of the obtained synthetic leather to be 0.72 mm.

(evaluation of various physical Properties)

The mechanical properties and abrasion durability were as shown in table 2, and the physical properties sufficient as synthetic leather were satisfied. Further, the flame-retardant test for the interior material of an automobile showed self-extinguishing within a 38mm mark, and the flame-retardant test for the interior material of an airplane showed no afterflame nor dripping flame, and the flame length was 50mm in the longitudinal direction and 54mm in the transverse direction, which are good results. The obtained synthetic leather was coated on a urethane cushion material and subjected to a flame retardant test on a seat cushion material, and as a result, the combustion length was also within a satisfactory range, and the mass reduction rate was 5.4% within a satisfactory range. The resulting cushioning material had a slightly hard texture, and the average score of sensory evaluation was 3.2.

Comparative example 1

(production of fibrous substrate layer)

The fibers used were only meta-aramid fibers, and the basis weight was 178g/m²A nonwoven fabric was produced in the same manner as in example 1, except that the thickness was 1.49 mm.

(production of synthetic leather)

The weight per unit area of the polyurethane resin D-1 and the flame retardant constituting the wet synthetic leather after drying was changed to 204g/m²The nonwoven fabric obtained by the above method was used as a fibrous base layer, and the synthetic leather laminated with the film had a weight per unit area changed to 432g/m²A synthetic leather was produced in the same manner as in example 1, except that the thickness was changed to 1.31 mm. The penetration depth of the resin layer and the adhesive layer into the fibrous base layer was 0.39mm as calculated from the SEM photograph of the cross section of the obtained synthetic leather.

(evaluation of various physical Properties)

The mechanical properties and abrasion durability were as shown in table 3, and the physical properties sufficient as synthetic leather were satisfied. Further, the flame-retardant test for the interior material of an automobile showed self-extinguishing within a 38mm mark, and the flame-retardant test for the interior material of an airplane showed neither afterflame nor dripping flame, and showed good results with a flame length of 52mm in the longitudinal direction and 54mm in the transverse direction. The resulting synthetic leather was coated on a urethane cushion material and subjected to a flame retardant test for a seat cushion material, and as a result, the combustion length was within the acceptable range, but the mass reduction rate was not satisfactory, and was 10.6%. The resulting cushioning material had soft and good texture.

Comparative example 2

(production of fibrous substrate layer)

The used fiber was PET fiberA fiber and a rayon fiber, wherein the mass ratio of the PET fiber to the rayon fiber is 65:35, and the unit area weight is 179g/m²A nonwoven fabric was produced in the same manner as in example 1, except that the thickness was 1.34 mm.

(production of synthetic leather)

The dried basis weights of the polyurethane resin D-1 and the flame retardant constituting the wet synthetic leather were changed to 195g/m²The nonwoven fabric obtained by the above method was used as a fibrous base layer, and the synthetic leather laminated with the film had its basis weight changed to 422g/m²A synthetic leather was produced in the same manner as in example 1, except that the thickness was changed to 1.42 mm. The penetration depth of the resin layer and the adhesive layer into the fiber base layer was 0.45mm as calculated from the SEM photograph of the cross section of the obtained synthetic leather.

(evaluation of various physical Properties)

The mechanical properties and abrasion durability were as shown in table 3, and the physical properties sufficient as synthetic leather were satisfied. In addition, although the flame-retardant test for the automobile interior material burned beyond the 38mm mark, the combustion rate was 98 mm/min, which was within the acceptable range. In the flame retardant test facing the airplane interior material, the continuous combustion is carried out for 3.4 seconds in the longitudinal direction and 3.2 seconds in the transverse direction; the dripping combustion time is 1.2 seconds in the longitudinal direction and 1.9 seconds in the transverse direction; the burning length was 167mm in the longitudinal direction and 169mm in the transverse direction, within the acceptable range. The obtained synthetic leather was coated on a urethane cushion material, and a flame retardant test of a seat cushion material was carried out, with the result that the combustion length was not satisfactory, the mass reduction rate was 24.7%, and neither was satisfactory. The resulting cushioning material had soft and good texture. Has the characteristics.

[ Table 1]

[ TABLE 1]

[ Table 2]

[ TABLE 2]

[ Table 3]

[ TABLE 3]

Industrial applicability

The flame retardant composition of the present invention has excellent flame retardancy, exhibits an excellent flame retardant effect when coated with a combustible material, and has excellent physical properties such as texture and peel strength, and therefore can be suitably used for interiors of automobiles, railways, ships and the like (seats, headrests, canopy, sunvisors, ceilings and the like), interior materials of high-rise buildings and public facilities, skin materials of furniture (chairs, sofas and the like), and the like, and is particularly suitable for seat interiors of airplanes which require high flame retardancy.

Description of the reference numerals

1 urethane foam (seat surface)

2 urethane foam (Back)

3 "Velcro (registered trademark)" adhesive tape

4 skin material (seat surface)

5 skin material (Back)

6 burner

7 coated article

8 interface of fiber base material layer in the state of laminating resin layer

9 interface of the penetrated resin layer