JP2014217995A - Cushion material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cushion material excellent in use feeling and having high flame resistance.SOLUTION: The cushion material is produced by laminating a fiber sheet having a basis weight equal to or more than 300g/mon at least one surface of a fiber structure including a heat adhesive short fiber and a main body fiber. The main body fiber includes one selected from a group consisting of an aramid fiber, a polytetrafluoroethylene fiber, a polyphenylene sulfide fiber, a flame-resisting rayon fiber, a flame-resisting acrylic fiber, a phenol-based fiber, a carbon-preoxide fiber, a carbon fiber, and a glass fiber, and a weight ratio of the heat adhesive short fiber and the main body fiber (heat adhesive short fiber: main body fiber) is in a range of 15:85-40:60. The fiber sheet includes one selected from a group consisting of the aramid fiber, the polytetrafluoroethylene fiber, the polyphenylene sulfide fiber, the flame-resisting rayon fiber, the flame-resisting acrylic fiber, the phenol-based fiber, the carbon-preoxide fiber, the carbon fiber, the glass fiber in an amount equal to or more than 90 wt.% with respect to a weight of the fiber sheet.

Description

  The present invention relates to a cushioning material having excellent usability and high flame retardancy.

Conventionally, as a cushion material for vehicle seats, a material made of polyurethane farm has been widely used (see, for example, Patent Document 1 and Patent Document 2).
However, the seat cushion material using polyurethane foam is not sufficient in terms of air permeability and further has problems such as yellowing.

Also, in order to improve recyclability, breathability, cushioning, and molding followability, elastic fibers containing non-elastic polyester crimped short fibers as the main fiber and elastic composite fibers with thermoplastic elastomer exposed on the fiber surface are dispersed and mixed A composite fiber structure in which a fabric is bonded to a structure has been proposed (see, for example, Patent Document 3 and Patent Document 4).
However, in any of the cushion materials, for example, when used as a cushion material for a vehicle seat, it has not been sufficient in terms of flame retardancy.

Japanese Patent Laid-Open No. 2002-3713 JP 2005-186499 A JP-A-8-230084 Japanese Patent Laid-Open No. 9-201481

  An object of the present invention is to provide a cushioning material having excellent usability and high flame retardancy.

  The present inventor constituted a fiber structure using a heat-adhesive short fiber and a main fiber composed of a flame-retardant fiber in a specific weight ratio, and laminated the flame-retardant fiber sheet on the fiber structure. The present inventors have found that a cushion material having excellent usability and high flame retardancy can be obtained, and further intensive studies have been made to complete the present invention.

Thus, according to the present invention, “a cushion material obtained by laminating a fiber sheet having a basis weight of 300 g / m ² or more on at least one surface of a fiber structure including a heat-adhesive short fiber and a main fiber, the main fiber As any fiber selected from the group consisting of aramid fiber, polytetrafluoroethylene fiber, polyphenylene sulfide fiber, flame retardant rayon fiber, flame retardant acrylic fiber, phenolic fiber, carbon precursor fiber, carbon fiber and glass fiber And the weight ratio of the heat-adhesive short fibers to the main fibers is in the range of (heat-adhesive short fibers: main fibers) 15:85 to 40:60, and the fiber sheet is aramid Fiber, polytetrafluoroethylene fiber, polyphenylene sulfide fiber, flame retardant rayon fiber, flame retardant acrylic fiber, fiber There is provided a cushioning material comprising 90% by weight or more of any fiber selected from the group consisting of enol fiber, carbon oxide fiber, carbon fiber, and glass fiber with respect to the fiber sheet weight.

In that case, it is preferable that the said heat bondable short fiber consists of a thermoplastic elastomer and nonelastic polyester, and the thermoplastic elastomer is a fiber exposed to the fiber surface. Further, the fiber structure is a mixture of a heat-bondable short fiber and a main fiber, and a heat-bonded fixing point and / or the heat-bondable short fiber in a state where the heat-bondable short fibers cross each other. It is preferable that the fiber structure is formed by interspersed with fixing points thermally fused in a state where the main fibers intersect. Moreover, it is preferable that the main fibers and the heat-adhesive short fibers are arranged in the thickness direction of the fiber structure. Moreover, it is preferable that the density of the said fiber structure exists in the range of 20-50 kg / m < ³ >. Moreover, it is preferable that the density of the said fiber sheet exists in the range of 0.05-0.20 g / cm < ³ >. Moreover, it is preferable to have a non-combustible sheet having a basis weight of 50 g / m ² or more between the fiber structure and the fiber sheet. Moreover, it is preferable that the said fiber structure and the said fiber sheet are integrally molded. Moreover, it is preferable that the thickness of a cushion material exists in the range of 40-120 mm. Moreover, it is preferable that a cushion material is for vehicle seats.

  ADVANTAGE OF THE INVENTION According to this invention, the cushion material which is excellent in a usability | use_condition and has high flame retardance is obtained.

It is a figure for demonstrating the direction of the arrangement | sequence of a heat bondable composite staple fiber or a main fiber in a fiber structure. It is a figure which shows typically an example of the molding method of the cushioning material of this invention.

In the cushioning material of the present invention, a fiber sheet having a basis weight of 300 g / m ² or more is laminated on at least one surface of a fiber structure including the heat-adhesive short fibers and the main fibers.
Here, in order to obtain high flame retardancy, as the main fiber, aramid fiber, polytetrafluoroethylene fiber, polyphenylene sulfide fiber, flame retardant rayon fiber, flame retardant acrylic fiber, phenol fiber, carbon oxide fiber, carbon It is important to include any fiber selected from the group consisting of fiber and glass fiber. When such a fiber is not included as the main fiber, the flame retardancy of the cushion material may be lowered, which is not preferable. It is most preferable that the main fiber is composed only of such fibers, but other fibers such as polyester fibers and nylon fibers may be included. At that time, the content of the other fibers is preferably less than 50% by weight with respect to the total weight of the main fibers.

  The aramid fibers include meta-type aramid fibers and para-type aramid fibers. The para-type aramid fiber may be poly-p-phenylene terephthalamide (PPTA) or copolymer type copolyparaphenylene-3,4'oxydiphenylene terephthalamide (PPODPA).

The main fiber may be not only a fiber made of a single polymer but also a composite fiber such as a side-by-side type or a core-sheath type. Moreover, the fiber which added the flame retardant and the atypical cross section fiber may be sufficient. The main fiber may be one type or a combination of a plurality of types.
In the main fiber, the single fiber fineness is preferably 1 dtex or more (more preferably 1 to 30 dtex, particularly preferably 6 to 10 dtex) in order to obtain excellent cushioning properties. If the single fiber fineness is smaller than 1 dtex, the cushioning property may be lowered.

  Moreover, it is preferable that the main fiber is crimped. At that time, the number of crimps is preferably 2 to 30 / 2.54 cm, and the degree of crimp is preferably 5 to 40%. If the number of crimps or the degree of crimp is smaller than the above range, the web may be difficult to be bulked or web formation may be difficult. On the other hand, if the number of crimps or the degree of crimp is too larger than the above range, the entanglement of the fibers becomes strong during web formation, which may cause defects such as streaky irregularities.

  In the main fiber, the fiber length is preferably 5 mm or more, more preferably 30 to 100 mm. If the fiber length is less than 5 mm, sufficient cushioning properties may not be obtained. Conversely, if the fiber length is greater than 100 mm, the process stability may be impaired.

  On the other hand, as the heat-adhesive short fibers, a low-melting-point heat-fusion component having a melting point 40 ° C. or more lower than the melting point of the main fiber is disposed on at least a part of the fiber surface, Are preferably short fibers that can be melted and fused with the main fibers or the heat-adhesive composite short fibers. If this difference in melting point is less than 40 ° C., the processing temperature will be close to the melting point of the main fiber, and the physical properties of the main fiber may be lowered, or the shrinkage during molding may be increased.

  Here, as a polymer arranged as a heat-fusion component, polyurethane elastomer, polyester elastomer, inelastic polyester polymer and copolymer thereof, polyolefin polymer and copolymer thereof, polyvinyl alcohol polymer, etc. Can be mentioned. Of these, thermoplastic elastomers are preferred.

  Examples of polyurethane elastomers include low-melting-point polyols having a molecular weight of about 500 to 6000, such as dihydroxy polyether, dihydroxy polyester, dihydroxy polycarbonate, dihydroxy polyester amide, and the like, and organic diisocyanates having a molecular weight of 500 or less, such as p, p′-diphenylmethane. Diisocyanate, tolylene diisocyanate, isophorone diisocyanate hydrogenated diphenyl methane isocyanate, xylylene isocyanate, 2,6-diisocyanate methyl caproate, hexamethylene diisocyanate and the like, and a chain extender having a molecular weight of 500 or less, such as glycol amino alcohol or triol It is a polymer obtained by the reaction.

  Among these polymers, particularly preferred is a polyurethane using polytetramethylene glycol, poly-ε-caprolactam or polybutylene adipate as a polyol. Examples of the organic diisocyanate in this case include p, p'-bishydroxyethoxybenzene and 1,4-butanediol.

  In addition, as a polyester-based elastomer, a polyetherester copolymer obtained by copolymerizing thermoplastic polyester as a hard segment and poly (alkylene oxide) glycol as a soft segment, more specifically, terephthalic acid, isophthalic acid, phthalic acid Alicyclic dicarboxylic acids such as naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, diphenyl-4,4′-dicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, succinic acid, oxalic acid, At least one dicarboxylic acid selected from aliphatic dicarboxylic acids such as adipic acid, sebacic acid, dodecanedioic acid, dimer acid, or ester-forming derivatives thereof, 1,4-butanediol, ethylene glycol trimethylene glycol, Tetramethylene glycol, Aliphatic diols such as tamethylene glycol, hexamethylene glycol neopentyl glycol, decamethylene glycol, or alicyclic diols such as 1,1-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, tricyclodecane methanol, or the like At least one diol component selected from ester-forming derivatives and the like, and polyethylene glycol, poly (1,2- and 1,3-polypropylene oxide) glycol, poly (tetramethylene oxide) having an average molecular weight of about 400 to 5000 ) Consists of at least one of poly (alkylene oxide) glycols such as glycols, copolymers of ethylene oxide and propylene oxide, copolymers of ethylene oxide and tetrahydrofuran, etc. It can be mentioned terpolymer.

  In particular, from the viewpoint of adhesiveness, temperature characteristics, and strength, a block copolymer polyether ester having polybutylene terephthalate as a hard component and polyoxybutylene glycol as a soft segment is preferable. In this case, the polyester portion constituting the hard segment is polybutylene terephthalate in which the main acid component is terephthalic acid and the main diol component is a butylene glycol component. Of course, part of this acid component (usually 30 mol% or less) may be substituted with another dicarboxylic acid component or oxycarboxylic acid component, and part of the glycol component (usually 30 mol% or less) is also butylene. It may be substituted with a dioxy component other than the glycol component. Further, the polyether portion constituting the soft segment may be a polyether substituted with a dioxy component other than butylene glycol.

  Copolyester polymers include aliphatic dicarboxylic acids such as adipic acid and sebacic acid, aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and naphthalenedicarboxylic acid and / or fats such as hexahydroterephthalic acid and hexahydroisophthalic acid. A co-polymer containing a predetermined number of cyclic dicarboxylic acids and aliphatic or alicyclic diols such as diethylene glycol, polyethylene glycol, propylene glycol, and paraxylene glycol, with addition of oxyacids such as parahydroxybenzoic acid as desired. Polymerized esters and the like can be mentioned. For example, polyesters obtained by adding and copolymerizing isophthalic acid and 1,6-hexanediol in terephthalic acid and ethylene glycol can be used.

Examples of the polyolefin polymer include low density polyethylene, high density polyethylene, and polypropylene.
In addition, various stabilizers, ultraviolet absorbers, thickening branching agents, matting agents, coloring agents, other various improving agents, and the like may be blended in the above-described polymer as necessary.

  In the heat-bondable composite short fiber, non-elastic polyester is preferably exemplified as the counterpart component of the heat-sealing component. In that case, it is preferable that the heat fusion component occupies at least a half of the surface area. The weight ratio is preferably in the range of 30/70 to 70/30 in terms of the composite ratio of the heat fusion component and the non-elastic polyester. Although it does not specifically limit as a form of a heat bondable composite staple fiber, It is preferable that a heat-fusion component and the other party component are a side-by-side and a core-sheath type, More preferably, it is a core-sheath type. In this core-sheath type heat-adhesive composite short fiber, the non-elastic polyester is the core and the heat-sealing component is the sheath, but the core may be concentric or eccentric.

In such a heat-adhesive composite short fiber, the single fiber fineness is preferably 0.5 to 10 dtex (more preferably 5 to 10 dtex).
Moreover, in the said heat bondable composite staple fiber, fiber length is preferable 5 mm or more, More preferably, it is 30-100 mm. If the fiber length is less than 5 mm, sufficient cushioning properties may not be obtained. Conversely, if the fiber length is greater than 100 mm, the process stability may be impaired.
Further, it is preferable that the heat-adhesive composite short fiber is provided with the same crimp as the main fiber.

  In the fiber structure, it is important that the weight ratio of the heat-adhesive short fibers and the main fibers is in the range of (heat-adhesive short fibers: main fibers) 15:85 to 40:60. When the weight ratio of the heat-adhesive short fibers is smaller than the above range, the heat fixing points described later are decreased, and as a result, the fiber structure becomes soft (no stiffness), and the cushioning property may be lowered. Absent. On the contrary, if the weight ratio of the heat-adhesive short fibers is larger than the above range, the flame retardancy may be lowered, which is not preferable.

In addition, as the fiber structure, the main fiber and the heat-adhesive short fibers are mixed and subjected to heat treatment so that the heat-adhesive short fibers are heat-sealed in a crossed state and / or Or it is preferable that it is a fiber structure in which the fixing points thermally fused in a state where the heat-adhesive short fibers intersect with the main fibers are scattered.
In the fiber structure, it is preferable that the main fibers and the heat-bonding composite short fibers are arranged in the thickness direction of the fiber structure because cushioning properties are improved. Here, “arranged in the thickness direction” means that the total number of fibers arranged in parallel to the thickness direction of the fiber structure is (T) and the thickness direction of the fiber structure is On the other hand, when the total number of fibers arranged vertically is (H), T / H is 1.5 or more.

  The method for producing such a fiber structure is not particularly limited, and a conventionally known method may be arbitrarily adopted. For example, after spinning as a uniform web with a roller card, the main fiber and the heat-bonding composite short fiber are arranged in the thickness direction of the fiber structure by mixing the main fiber and the heat-bonding composite short fiber. Then, after spinning as a uniform web with a roller card, using a heat treatment machine as shown in FIG. The method of forming is preferably exemplified. For example, a device disclosed in Japanese Translation of PCT International Publication No. 2002-516932 (for example, commercially available Strut equipment manufactured by Struto Corporation) may be used. When the main fibers and the heat-bonded composite short fibers are not arranged in the thickness direction of the fiber structure, it is preferable to heat-treat after laminating the web containing the main fibers and the heat-bonded composite short fibers by a conventional method.

The density of the fiber structure is preferably in the range of 20 to 50 kg / m ³ . If the density is less than 20 kg / m ³ , cushioning properties may be reduced. On the contrary, if the density is higher than 50 kg / m ³ , not only the lightness may be impaired, but also when the cushion material of the present invention is used as, for example, a vehicle seat, There is a risk of great stress on the part.

  The thickness of the fiber structure is preferably in the range of 2 to 200 mm (more preferably 30 to 150 mm). If the thickness is less than 2 mm, the cushioning property may be lowered. On the other hand, if the thickness is greater than 200 mm, the lightness may be impaired or a space problem may occur.

In the cushioning material of the present invention, at least one surface of the fiber structure includes an aramid fiber (including a meta-type aramid fiber and a para-type aramid fiber), a polytetrafluoroethylene fiber, a polyphenylene sulfide fiber, a flame retardant rayon fiber, Weight per unit area including 90% by weight or more (most preferably 100% by weight) of any fiber selected from the group consisting of flame retardant acrylic fiber, phenolic fiber, carbon oxide fiber, carbon fiber and glass fiber with respect to the fiber sheet weight 300 g / ^{m 2} or more (preferably 400~1000g / ^{m 2)} fiber sheet are laminated. When such a fiber sheet is not laminated | stacked, the flame retardance of a cushion material falls and it is unpreferable.

In the fiber sheet, when the basis weight is less than 300 g / m ² , the melt of the fiber structure arranged in the inner layer may elute to the outer surface of the fiber sheet, which may cause a flame to propagate and increase the combustion. Absent. On the other hand, when the basis weight is larger than 1000 g / m ² , the lightweight property of the cushion material may be impaired. Moreover, in the said fiber sheet, when content of the said fiber is less than 90 weight%, there exists a possibility that a flame retardance may fall and it is unpreferable.

  In the fiber sheet, the fabric structure is not limited, and any of a nonwoven fabric, a woven fabric, and a knitted fabric may be used. However, a nonwoven fabric is preferable because the melt of the fiber structure disposed in the inner layer does not elute to the outer surface of the fiber sheet. In that case, as a manufacturing method of a nonwoven fabric, a needle punch method, a water needle method, an airlaid method, a wet method, etc. are illustrated.

In the fiber sheet, the density is preferably in the range of 0.05 to 0.20 g / cm ³ . When the density of a fiber sheet is smaller than this range, there exists a possibility that the melt of the fiber structure arrange | positioned at the inner layer may elute even to the outer surface of a fiber sheet. On the contrary, when the density of the fiber sheet is larger than the above range, the lightweight property of the cushion material may be impaired.

When laminating the fiber sheet on the fiber structure, it is preferable that the fiber structure is sandwiched between two fiber sheets because flame retardancy is improved. In particular, it is preferable that the fiber sheet is laminated on all the upper, lower, front, rear, and right and left sides of the fiber structure so as to wrap the fiber structure.
The fiber structure may be used as a single layer, or a plurality of the fiber structures may be stacked. Further, different density fiber structures may be laminated and used. For example, the fiber structure having a good cushioning property is placed in the middle layer and the surface layer with a high-hardness fiber structure, or a high-density fiber structure is arranged on the side portion for strength reinforcement, which makes the seat comfortable. A seat cushion material can be obtained.

  In addition, the fiber structure may be sliced by a slicer facility or the like approximately perpendicularly to the thickness direction or slightly obliquely as necessary, and a sheet-like material may be bonded to the sliced cut surface. By sticking the sheet-like material to the cut surface of the fiber structure in this manner, the cut surface of the fiber structure is flat, so that the surface of the sheet-like material after bonding is also flat. Furthermore, when the fibers are arranged in the thickness direction, the friction with the fibers contained in the fiber structure also increases, and bonding becomes easy.

In addition, when a non-combustible sheet having a basis weight of 50 g / m ² or more (more preferably 200 to 500 g / m ² ) is interposed between the fiber structure and the fiber sheet, the melt of the fiber structure is removed from the fiber sheet. It is preferable because it can prevent elution to the surface.
Such non-combustible sheets include commercially available heat-insulating glass cloth, carbon fiber, glass wool, rock wool and other surface-coated cloth, and those with soft aluminum affixed to their surfaces, and metal sheets such as iron, aluminum, copper , Stainless steel, titanium, aluminum / zinc alloy plated steel plate, enameled steel plate, clad steel plate, laminated steel plate (PVC steel plate, etc.), sandwich steel plate (damping steel plate, etc.) (including color metal plates coated with various colors) One of these is formed into a sheet by roll molding, press molding, extrusion molding, or the like.

  As a method of laminating a fiber sheet on the fiber structure, after manufacturing the fiber structure, the fiber sheet is superimposed on the upper surface and / or the lower surface of the fiber structure, and further, if necessary, an incombustible sheet is interposed, A method of thermocompression bonding with a mold, a roll, a belt or the like is preferable. At that time, the fiber structure and the incombustible sheet are bonded by remelting the heat-adhesive short fibers contained in the fiber structure, but in order to further improve the adhesive strength, an adhesive such as powder, hot melt nonwoven fabric, hot melt film, etc. It is also possible to use together.

  Here, integral molding is preferred as a method of laminating a fiber sheet on the fiber structure. When a cushion material is obtained by joining a plurality of sheets, a flame propagates easily from the joining point and burns easily, and further, an adhesive resin for joining promotes combustion, so the cushion material is integrally molded. It is preferable. In addition, the molding method is vacuum moist heat molding for obtaining uniform hardness and excellent cushioning characteristics, that is, the fiber structure is placed in a molding die in which steam holes are formed on the mold surface, and steam is formed in a pressed state. Therefore, a method of obtaining a cushioning material is preferable.

At this time, the amount of steam sprayed onto the fiber structure during molding can be varied by changing the aperture ratio of the steam holes on the mold surface. For example, it can be finished in a soft state at a portion where the opening ratio of the steam holes is small, and can be finished in a hard state at a portion where the opening ratio of the steam holes is large.
Furthermore, known functional processing such as normal dyeing processing, raising processing, water repellent processing, flameproof processing, flame retardant processing, and negative ion generation processing may be added. As long as the object of the present invention is not impaired, other additives such as other sheet-like materials may be added as appropriate.

The cushion material thus obtained preferably has a thickness in the range of 40 to 120 mm. If the thickness is smaller than this range, the cushioning property may be impaired. On the other hand, if the thickness is larger than this range, the lightness may be impaired.
Since this cushion material contains the above-mentioned fiber structure and fiber sheet, it has good cushioning properties and excellent usability, and also has high flame retardancy.
Such a cushioning material is suitably used as a cushioning material for vehicle seats (chairs) for Shinkansen, high-speed railways, trains, trains, automobiles, airplanes, ships, and other various transport aircraft. Of course, it may be used for furniture, office chairs, sofas, bedding, and the like.

  Next, although the Example and comparative example of this invention are explained in full detail, this invention is not limited by these. In addition, each measurement item in an Example was measured with the following method.

(1) Melting point Using a differential thermal analyzer 990 manufactured by Du Pont, measured at a temperature increase of 20 ° C./min, and obtained a melting peak. When the melting temperature was not clearly observed, the melting point was defined as the temperature at which the polymer softened and started to flow (softening point) using a micro melting point measuring device (manufactured by Yanagimoto Seisakusho).

(2) Number of crimps The number of crimps was measured by the method described in JIS L 1015 7.12. In addition, the average value was calculated | required by n number 5.

(3) Thickness It was measured according to JIS L1085.

(4) Weight per unit area Measured according to JIS L1085.

(5) Density and hardness Measured according to JIS K-6401. In addition, the average value was calculated | required by n number 5.

(6) T / H
The fiber structure is cut in the thickness direction, and the cross section of the heat-adhesive composite short fibers and the main fibers (0 ° ≦ θ ≦ 45 ° in FIG. 1) arranged in parallel to the thickness direction. The total number is T, and the total number of heat-adhesive composite short fibers and main fibers (45 ° <θ ≦ 90 ° in FIG. 1) arranged perpendicular to the thickness direction of the fiber structure is H. / H was calculated. In addition, the measurement of the number was carried out by observing 30 fibers for each of 10 arbitrary positions with a transmission optical microscope, and counting the number. When T / H was 1.5 or more, it was determined that “fibers are arranged in the thickness direction”.

(7) Flame retardance In accordance with ASTM-E162, the sample is inclined 30 ° C so that it is 121 mm at the top and 367 mm at the bottom with respect to the radiant panel (radiant plate) heated to 670 ° C installed vertically. The flame propagation index was measured by determining the rate at which the flame propagated through the surface of the sample (propagation rate) and the temperature rise in the exhaust pipe at the top of the apparatus. The lower the index value, the harder it is to burn.

(8) Molding followability Three-step judgment of ○, Δ, and × was made by visual judgment in terms of ease of molding at the time of molding and a finished state after molding. (○: Easy to mold, good finish. △: Easy to mold, but slightly poor finish, wrinkles and size fluctuations. ×: Wrinkles and size fluctuations are large, and molding is very difficult. Difficult.)

[Example 1]
A single-fiber fineness of 6.6 dtex, a fiber length of 51 mm, a crimp length of 12.5 pieces / 2.2 using a thermoplastic polyetherester type elastomer having a melting point of 154 ° C. as the sheath component and a melting point of 230 ° C. polybutylene terephthalate as the core component. 54cm core / sheath type thermal adhesive composite short fiber (core / sheath weight ratio = 60/40), single fiber fineness 6.6dtex, fiber length 51mm, difficulty of 25 crimps / 2.54cm Combustion rayon fiber (product name: Corona, manufactured by Daiwabo Rayon) at a weight ratio of 70:30, and then heat-bonding the fibers in a heat treatment furnace at a temperature of 200 ° C through a roller card, a cross ray, and a roller card in this order. A fiber structure having a thickness of 3 cm and a density of 20 kg / m ³ was obtained.
The fiber structure formed in this manner has a fixing point where heat-bonding composite staple fibers are cross-bonded to each other and a heat-bonding point where heat-adhesive composite staple fibers and main fibers cross each other. The attached fixing points were scattered.
On the other hand, as a fiber sheet, a predetermined fiber sheet A was obtained by blending with the configuration shown in Table 1 in the order of roller card, crosslay, and needle punching.

Next, the obtained fiber structure was cut into a predetermined shape and laminated in the thickness direction as shown in FIG. In this example, the fiber sheet A covering the outer periphery and the fiber structure B for reinforcing the strength of the peripheral edge are disposed, and the fiber structure C is disposed in the inner layer. Moreover, the hot-melt nonwoven fabric was arrange | positioned in the part which fiber structure AC contact | abuts mutually.
The fiber structures A to C laminated in this way are arranged in a molding die as shown in FIG. The mold 40 of this example is composed of a first mold (upper mold) and a second mold (lower mold) having steam holes. After the vacuum is applied, the steam is heated to 150 to 180 ° C. in a vacuum steam molding machine. After spraying, the mold was removed to obtain an uneven cushion material. In this example, the steam molding machine was heated under the condition that the temperature inside the steam forming machine reached 160 ° C. and maintained for 10 minutes. The heat-adhesive composite short fibers contained in the fiber structures A to C and the arranged hot melt nonwoven fabric were melted by steam heat, and the fiber structures A to C were fixed to obtain a cushion material having a predetermined shape. . The evaluation results are shown in Table 2.
Subsequently, when the cushion material was used as a cushion material for a vehicle seat, the feeling of use was excellent.

[Example 2]
A cushioning material was obtained in the same manner as in Example 1 except that meta-aramid fiber (trade name: Cornex, manufactured by Teijin Ltd.) was used as the main fiber in Example 1. The evaluation results are shown in Table 2. Although the flame retardancy was slightly lowered, a cushioning material having good cushioning properties was obtained.

[Example 3]
The web of the sheet-like fiber structure obtained in Example 1 was subjected to a hot air suction heat treatment machine (heat treatment zone length 5 m, moving speed) with a struto machine manufactured by Struto Corporation using a roller surface speed of 2.5 m / min. 1m / min), the web is folded and the majority of the fibers are arranged in the thickness direction (T / H = 4.7) and pushed into the accordion type. A fiber structure arranged in the thickness direction was obtained. Next, the fiber structure obtained in the same manner as in Example 1 was cut into a predetermined shape, laminated with a flame retardant fiber structure and the like, and molded to obtain a cushion material. The evaluation results are shown in Table 2. The cushion characteristics were good.

[Example 4]
In Example 1, between the fiber sheet A and the fiber structure C, a non-combustible sheet was woven (twill weave structure) with a density of 42 pieces / 25 mm and a width of 30 pieces / 25 mm, a basis weight of 288 g / m ² , A glass cloth fabric having a thickness of 0.2 mm was inserted, and a cushion material was produced in the same manner as in Example 1. The evaluation results are shown in Table 2. Extremely high flame retardant properties were obtained.

[Comparative Example 1]
In Example 1, except for using hollow polyethylene terephthalate having a single yarn fineness of 13.3 dtex having a three-dimensional crimp by anisotropic cooling, a fiber length of 64 mm, and a crimp number of 12 / 2.54 cm as the main fiber of the fiber structure B. A cushioning material was obtained in the same manner as in Example 1. The evaluation results are shown in Table 2. Although the cushioning properties were good, the flame retardant properties were poor.

[Comparative Examples 2 and 3]
In Example 1, a cushion material was obtained in the same manner as in Example 1 except that a fiber sheet as shown in Table 1 was used. The evaluation results are shown in Table 2. The flame retardant properties were significantly inferior, and in this test, the flame was propagated throughout the sample.

[Comparative Examples 4 and 5]
In Example 1, a cushioning material was obtained in the same manner as in Example 1 except that the blending ratio of the main fiber of the fiber structure and the heat-adhesive composite short fiber was as shown in Table 2. The evaluation results are also shown in Table 2, and the balance between flame retardancy and cushioning properties was poor.

  According to the present invention, a cushion material having excellent usability and high flame retardancy can be obtained, and its industrial value is extremely large.

A: Fiber sheet A
B: Fiber structure B
C: Fiber structure C

Claims (10)

A cushion material obtained by laminating a fiber sheet having a basis weight of 300 g / m ² or more on at least one surface of a fiber structure including a heat-adhesive short fiber and a main fiber,
The main fiber is any selected from the group consisting of aramid fiber, polytetrafluoroethylene fiber, polyphenylene sulfide fiber, flame retardant rayon fiber, flame retardant acrylic fiber, phenolic fiber, carbon oxide fiber, carbon fiber, and glass fiber. Including some fibers,
And the weight ratio of the said heat bondable short fiber and the said main fiber is in the range of (thermal bondable short fiber: main fiber) 15: 85-40: 60,
The fiber sheet is selected from the group consisting of aramid fibers, polytetrafluoroethylene fibers, polyphenylene sulfide fibers, flame retardant rayon fibers, flame retardant acrylic fibers, phenolic fibers, carbon oxide fibers, carbon fibers, and glass fibers. A cushioning material comprising 90% by weight or more of any fiber relative to the weight of the fiber sheet.   The cushion material according to claim 1, wherein the heat-adhesive short fibers are made of a thermoplastic elastomer and an inelastic polyester, and the thermoplastic elastomer is a fiber exposed on the fiber surface.   In the fiber structure, a heat-bonding short fiber and a main fiber are mixed, and the heat-bonding short fiber and the main body are bonded together and / or the heat-bonding short fiber and the main body are bonded together. The cushion material according to claim 1 or 2, wherein the cushion material is a fiber structure formed by interspersed with fixing points thermally fused in a state where the fibers intersect.   The cushion material in any one of Claims 1-3 in which the said main fiber and the said heat bondable short fiber are arranged in the thickness direction of a fiber structure. The cushion material in any one of Claims 1-4 whose density of the said fiber structure exists in the range of 20-50 kg / m < ³ >. The cushion material in any one of Claims 1-5 whose density of the said fiber sheet exists in the range of 0.05-0.20 g / cm < ³ >. The cushion material in any one of Claims 1-6 which has a non-combustible sheet | seat with a fabric weight of 50 g / m < ² > or more between the said fiber structure and the said fiber sheet.   The cushion material according to any one of claims 1 to 7, wherein the fiber structure and the fiber sheet are integrally molded.   The cushion material in any one of Claims 1-8 which exists in the range whose thickness of a cushion material is 40-120 mm.   The cushion material according to any one of claims 1 to 9, wherein the cushion material is for a vehicle seat.