JPH09137350A - Cushioning structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cushioning structure improved in elastic recovery, resilience, stress dispersibility and durability. SOLUTION: This cushioning structure with a density of 0.005-0.2g/cm<3> and thickness of >=5mm comprises inelastic polyester crimped short fiber assembly as matrix and is so designed that elastic conjugate fibers composed of a thermoplastic elastomer with a melting point >=40 deg.C lower than that of the polyester polymer constructing the short fibers and an inelastic polyester with the former component exposed onto the fiber surface are dispersed in and mixed with the fiber assembly, there are in a scattered way (A) flexible heat-adhesion spots produced by mutual thermofusing of the elastic conjugate fibers in mutually crossed state and (B) another kind of flexible heat-adhesion spots produced by thermofusing the elastic conjugate fibers and inelastic polyester short fibers in mutually crossed state, and a smoothing lubricant lie adhered to the surface of the fibers on at least one side surface layer of this structure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a soft texture when worn by being put in a side material or a skin material, has a good breathability and does not easily get damp, and has a good handleability such as folding storage ability and easiness of bending. Easy to put in and take out from the side material and skin material, shape retention, good wear resistance of cushioning material and good durability, stuffed fiber used not only alone but also laminated with other cushioning material or fiber web And a cushion structure comprising the same. More particularly, it relates to a cushion structure having further improved elasticity, stress dispersion and durability.

[0002]

2. Description of the Related Art Conventionally, a fiber cushion material in which fibers are fused by using low melting point fibers is disclosed in Japanese Examined Patent Publication (Kokoku) No. 1-18183, Japanese Unexamined Patent Publication (Kokai) No. 4-126856, and Japanese Unexamined Patent Publication (Kokai) No. 3-220.
No. 354, Republication No. 3-819082, etc. In addition, an integrally molded cushion material in which the skin material is heated and pressed with the same low melting point heat-adhesive fiber as the fiber cushion material to bond and integrate it and the skin material is used as it is on the surface (JP-A-60-
No. 40239), a vehicle seat in which the side is integrated with a polyester elastomer (JP-A-5-337258), and the like are proposed.

Further, in Japanese Patent Publication No. 34435/1992, a crimped synthetic fiber staple and a high melting point polymer are used as cores,
A crimped synthetic fiber staple in which a core-sheath type crimped synthetic fiber staple having a low melting point polymer as a sheath is alternately bonded, and a crimped synthetic fiber staple provided with a silicone resin is A stuffing body has been proposed which is blended without substantially binding to the fibers.

However, in order to maintain the shape of the conventional fiber-molded cushion material by molding, the density of the bonding points between the fibers is required to some extent, so that the compression hardness of the fiber cushion material becomes hard. However, when it is used alone, the problem that it is hard is likely to occur, and it is often necessary to laminate it with a soft web layer, which increases the cost and the process.

Further, in the above-mentioned filled object, the fiber to which the silicone resin is applied does not bond with the core-sheath type fiber, and the bonding points are reduced as a whole, and it has a unique texture, but the hardness and the repulsion are high. The strength is slightly insufficient, and further improvement in shape retention and durability is desired. An object of the present invention is to provide a cushion structure having flexibility in a fixed state at a bonding point of short fibers, and thus improved in cushioning property, compression repulsion property, compression durability and compression recovery property. Another object is to provide a cushion structure having further improved elasticity, stress dispersion and durability.

[0006]

According to the present invention, the object of the present invention is to use a non-elastic polyester crimped short fiber aggregate as a matrix and to have a density of 0.005 to 0.2 g / cm.
^{3. In} the cushion structure having a thickness of 5 mm or more, in the short fiber aggregate, a thermoplastic elastomer having a melting point of 40 ° C. or more lower than the melting point of the polyester polymer forming the short fibers and an inelastic polyester are used. In the former, at least the elastic composite fibers exposed on the surface of the fibers are dispersed and mixed, and at that time, in the cushion structure, (A) the elastic composite fibers are formed by heat fusion with each other in an intersecting state. Flexible heat fixing point, and (B)
Flexible elastic fixing points formed by heat fusion in a state where the elastic composite fibers and the non-elastic polyester short fibers are interspersed, and the fibers in at least one surface layer of the cushion structure are It has been found to be achieved by a cushion structure characterized in that a smooth oil is attached to the fiber surface.

That is, the cushion structure of the present invention is
As described above, the non-elastic polyester crimped short fibers in the matrix are heat-sealed by the elastic composite fibers, and the flexible heat fixing points of (A) and (B) are scattered, and the structure thereof is The fibers in at least one surface layer of the body or the whole of the body have a smooth oil agent attached to the fiber surface. Therefore, the fibers are slippery against pressure deformation,
The internal stress is reduced, and the repulsive force, elastic recovery and durability are greatly improved.

The present invention will be described in more detail below. The non-elastic polyester short fibers forming the matrix in the cushion structure in the present invention are ordinary polyethylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, polytetramethylene terephthalate, poly-1,4-dimethylcyclohexane terephthalate, A short fiber made of polypivalolactone or a copolymer ester thereof or a mixed fiber of these fibers, or a composite fiber made of two or more kinds of the above polymers. The cross-sectional shape of the short fibers may be circular, flat, irregular or hollow. In particular, short fibers made of polyethylene terephthalate or its copolymer are preferable.

Since the polyester short fibers are fused by the elastic composite fibers to form a matrix which is a framework of the cushioning material, the polyester short fibers alone are required to be bulky and exhibit repulsion. . The bulkiness alone (JIS L-1097) is preferably 50 cm ³ / g or more under a load of 0.5 g / cm ² , and 20 cm ³ / g or more under a load of 10 g / cm ² , and more preferably It is desirable that they are 60 cm ³ or more and 25 cm ³ / g or more, respectively. When the sublimation property is low, problems such as low elasticity and compression repulsion of the obtained fiber-molded cushion material become remarkable.

The short fibers may have a fineness of 4 denier or more, preferably 4 to 500 denier, and more preferably 8 to 200 denier. When the fineness is less than 4 denier, the bulkiness is not exhibited, and the cushioning property and the repulsion force become poor. On the other hand, when it is more than 500 denier, it is difficult to make the fibers into a web, and the number of constituent fibers of the obtained fiber-formed cushioning material becomes too small, resulting in coarse hardness and poor cushioning properties.

On the other hand, the number of crimps of the polyester short fiber is
It is preferable that the number of crimps is 4 to 25 pieces / inch and the crimping degree is 10 to 40%. If the number of crimps or the degree of crimping is too small, it is not preferable because it makes it difficult for the feb to be bulky and makes it difficult to form a web. The resulting cushioning material also has poor resilience and only low durability. On the other hand, if the number of crimps or the degree of crimping is too large, the bulkiness of the web does not increase and only a high-density cushioning material can be obtained. It is not possible to do it. Fiber length of the polyester short fibers is 5 m
m or more, preferably 10 to 100 mm, particularly preferably 15 mm to 90 mm is advantageous.

On the other hand, in the cushion structure of the present invention, the elastic composite fiber for fusing the short fiber aggregate as the matrix has a low melting point having a melting point of 40 ° C. or more lower than the melting point of the non-elastic polyester short fiber as the matrix. Of the thermoplastic elastomer of the present invention is an elastic composite fiber having at least a part thereof, especially on the surface of the fiber, and at least a part of the surface thereof is melted by heating and is a polyester-based short fiber or a short fiber capable of being fused with each other. . When the difference in melting point is 40 ° C. or less, the processing temperature becomes close to the melting point of the polyester short fibers, and the physical properties and crimping properties of the polyester short fibers are deteriorated, and the cushioning performance is deteriorated, or during molding. Contraction will increase.
From this point of view, the melting point of the low-melting thermoplastic elastomer is preferably 40 ° C. or more, particularly 60 ° C. or more lower than the melting point of the polymer constituting the short fiber. The melting point of such a thermoplastic elastomer can be, for example, a temperature in the range of 130 to 220 ° C.

In the cushion structure of the present invention, the elastic composite fiber used for forming the flexible heat fixing point that plays an important role is formed of a thermoplastic elastomer and a non-elastic polyester. In this case, the former preferably occupies at least half of the fiber surface. In terms of weight ratio, the former and the latter have a combined ratio of 30/70 to 70/3.
A value in the range of 0 is suitable. The form of the elastic conjugate fiber may be either side-by-side or sheath-core, but the latter is preferred. In this sheath-core type, of course, the core is inelastic polyester, but the core may be concentric or eccentric. In particular, an eccentric type is more preferable because a coiled elastic crimp is developed.

Thus, the cushion structure of the present invention is
During use, it is repeatedly compressed and deformed after heat fusion molding,
Moreover, in a cushioning application in which the amount of compression, that is, the amount of deformation is large (for example, 50% of the thickness), the heat fixing point is easily deformed when a deformation stress is applied, and when the deformation stress disappears, no distortion is left and the original It is necessary to easily return to the position. The fact that a large amount of deformation is applied to the fiber molded cushion means that the entanglement points of the low melting point polymer of the fibers forming the fiber structure are further changed in angle, stretched or twisted. And so on. Therefore, this heat-fixing polymer is required to have a property of being largely deformed and recovered, and therefore it is preferable to be composed of a thermoplastic elastomer having a large fracture elongation and a good elongation recovery property. A polyester elastomer is particularly preferable because the matrix fiber to be heat-fixed is a polyester fiber.

As the polyester elastomer, a polyether ester block 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, Aromatic dicarboxylic acids such as phthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene 2,7-dicarboxylic acid, diphenyl-4,4-dicarboxylic acid, diphenoxyethanedicarboxylic acid and sodium 3-sulfoisophthalate, 1 , 4
An alicyclic dicarboxylic acid such as cyclohexanedicarboxylic acid, succinic acid, oxalic acid, adipic acid, sebacic acid, dodecanedioic acid, an aliphatic dicarboxylic acid such as dimer acid, or a dicarboxylic acid selected from these ester-forming derivatives, etc. At least one and an aliphatic diol such as 1,4-butanediol, ethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, neopentylene glycol, decamethylene glycol, or 1,
At least one diol component selected from alicyclic diols such as 1-cyclohexadimethanol, 1,4-cyclohexanedimethanol, and tricyclodecanedimethanol, or ester-forming derivatives thereof, and an average molecular weight of about 400 to About 5000 polyethylene glycol, poly (1,2- and 1,3-propylene oxide) glycol, poly (tetramethylene oxide) glycol, copolymer of ethylene oxide and propylene oxide, copolymer of ethylene oxide and tetrahydrofuran, etc. Is a terpolymer composed of at least one of the poly (alkylene oxide) glycols.

However, a block copolymerized polyether polyester having polybutylene terephthalate as a hard segment and polyoxytetramethylene glycol as a soft segment from the viewpoints of adhesiveness with polyester short fibers, temperature characteristics, strength, physical properties, etc. 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, a part (usually 30 mol% or less) of this acid component may be substituted with another dicarboxylic acid component or an oxycarboxylic acid component, and likewise, a part of the glycol component may be a dioxycarboxylic acid component other than the butylene glycol derivative. It may be replaced with a component. Further, the polyether component constituting the soft segment may be a polyether substituted with a dioxy component other than tetramethylene glycol. It should be noted that various stabilizers, ultraviolet absorbers, thickening and branching agents, matting agents, coloring agents, and various other improving agents may be added to the polymer, if necessary.

On the other hand, in the elastic composite fiber of the present invention, the non-elastic polyester used as the counterpart component of the elastomer is selected from the polyesters constituting the crimped short fibers forming the matrix. Among them, polybutylene is particularly preferable. Terephthalate is more preferably used.

Since the elastic composite fibers are mixed with each other during the production of the fiber-molded cushioning material and are an adhesive component for forming the fiber structure, the denier is 2-1.
It is preferably 00 denier, and particularly preferably 4 to 100 denier. If the denier is small, the number of bonding points is too large, and it is difficult to provide cushioning. On the other hand, if it is too thick, the number of bonding points is too small and the resilience is too low, or it tends to come loose during use. Cut length 38-255 mm, crimp number 4-50
The number of pieces / inch is preferable. If it deviates from this range, it becomes difficult to mix and it becomes difficult to make a web.
In addition, the cushioning performance and compression durability of the molded product are also reduced.

The blending ratio of this low melting point elastic composite fiber is 1
Suitably 0 to 70% by weight. If the proportion of the low melting point composite fiber is less than 10% by weight, the number of adhesion points of the fiber structure will be too small, resulting in too low compression rebound and too low compression durability. On the other hand, the ratio is 70% by weight
If it becomes higher, the number of bonding points of the fiber structure is too large and only a hard cushioning property is obtained, or the low melting point fiber shrinks (generally, the low melting point fiber is Due to the heat-sealing property, it is difficult to heat-fix during production and the shrinkage is high), and it becomes difficult to obtain the shape of a predesigned molded product.

Particularly, as the cushion structure of the present invention,
A thermoplastic polyester having a polyester-crimped short fiber aggregate described in Japanese Patent Publication No. 3-819082 as a matrix and having a melting point of 40 ° C. or more lower than the melting point of the polyester constituting the short fibers in the short-fiber aggregate. An elastic composite fiber composed of an elastomer and a polyester, the former of which is at least exposed on the surface of the fiber, is dispersed and mixed therein, and in the cushion structure, (A) the elastic composite fibers are crossed with each other. A flexible heat fixing point formed by heat fusion, and (B) a flexible heat fixing point formed by heat fusion in a state where the elastic composite fiber and the non-elastic polyester short fiber cross each other. It is preferable that the cushion structures are scattered. The specific contents and manufacturing method are described in the above publication.

The structure of the cushion structure is such that the density at which the cushioning property is exhibited is 0.015 g / cm ^{3 to} 0.150 g.
/ Cm ³ is preferable, and the thickness of the cushion structure is preferably 2 cm or more. If the density is lower than this range, the fiber density will be too low and the resilience and compression durability will fall below the practical range. On the other hand, if the density is too high, the fiber density and the density of the bonding points will be too high and will be too hard.

The fiber-formed cushion structure of the present invention can be manufactured by various methods. Next, some of them will be described. That is, the cushion structure of the present invention is formed by mixing polyester short fibers and elastic composite fibers having a low melting point and opening with a card or the like to form a web, and then laminating a web or those webs, and placing the web in a mold having a predetermined shape. It is obtained by packing a fixed amount of web, compression and heat molding. In addition, sandwiching laminated webs, etc. in a conveyer consisting of a flat plate composed of a patching plate or caterpillar type upper and lower punching plates, pressurizing and heating at a temperature higher than the melting point of the elastic composite fiber and lower than the melting point of the polyester staple fiber. During heating or immediately after heating, it is compressed vertically or horizontally to press or heat at least part of the entanglement points between the elastic composite fibers and the polyester short fibers or the entanglement points between the elastic composite fibers. There is a method of obtaining a fiber-formed cushion structure having a predetermined shape while treating and heat-sealing.

The cushion structure of the present invention has a density of 0.
005 to 0.15 g / cm ³ , preferably 0.01 to 0.0
It is in the range of 8 g / cm ³ , and although it is lightweight, it has suitable compression resilience and compression durability as a cushioning material. Moreover, since it has excellent breathability, it can be used as various cushioning materials. The thickness may be 5 mm or more, and practically 10 mm or more.
The upper limit of the thickness is not particularly limited, but is generally 100 mm or less, particularly 50 mm or less.

Another feature of the cushion structure of the present invention
One is that it can be formed into various shapes as well as a flat plate shape, so that the shape and thickness may be changed according to the application, and it may be long such as a long chair.

In the cushion structure of the present invention, a smooth oil agent (hereinafter sometimes simply referred to as "oil agent") is attached to the surface of at least one surface layer of fibers. Oil may be attached to the entire fibers of the cushion structure,
The oil agent may be attached to the fibers of the surface layer on one side or both sides. Further, the cushion structure may be formed of two layers, a layer to which the oil agent is attached and a layer to which the oil agent is not attached. By attaching the fibers to the oil agent, the repulsion property, the stress dispersibility, the elastic recovery property and the durability are further improved, and the cushion structure is practically excellent. This effect is considered to be due to the fact that when the cushion structure is compressed and deformed due to the adhesion of the oil agent, the slipperiness of the fibers improves and the internal stress decreases.

The smoothing oil agent used is an oil agent for fibers which can impart smoothness to the fibers, and silicon-containing oils, particularly silicone oils, silicone modified oils, and fluorine modified oils are generally recommended. Specific examples thereof include non-reactive silicone oils such as dimethyl polysiloxane and diphenyl polysiloxane. Other than this, methylhydrogen polysiloxane, epoxy group-containing polysiloxane, etc. may be used,
These are preferably used after heat treatment after the adhesion treatment.

As a method for adhering the oil agent to the fibers of the cushion structure, a method of immersing the cushion structure in an emulsion containing the oil agent in an amount of about 0.05 to 1% by weight or spraying the emulsion on the cushion structure is used. The method of spraying on the surface layer is adopted.

[0028]

EFFECTS OF THE INVENTION The cushion structure of the present invention has improved resilience, stress dispersibility, elastic recovery and durability by adhering a smoothing oil agent to the fiber, and is a practical cushioning material. Become. Therefore, the cushion material can be used for various widening cushion materials.

[0029]

Hereinafter, the present invention will be described in detail with reference to examples. Example Polyethylene terephthalate hollow fiber short fibers (14de,
Eccentric elastic composite fiber (9 de, fiber length 64 mm) having a core component of polybutylene terephthalate and a polyester ester elastomer as a sheath component,
70% by weight of the former and 30% by weight of the latter were mixed with the core component: the sheath component = 50: 50). The obtained blended cotton is made into a web and 2
Dry heat treatment at 00 ℃ for 7 minutes, thickness 5cm and density 0.0
A cushion structure of 4 g / cm ³ was obtained. This structure was impregnated with an emulsion containing 5% of a reactive silicone oil agent by spraying 4% of the weight of the fiber, and then at 120 ° C. for 5 minutes.
Heat treated for minutes. The obtained cushion structure had improved elastic recovery, durability, and stress dispersibility as compared with those not treated with silicone oil. Table 1 shows the results
Shown in

[0030]

[Table 1]

Claims (5)

[Claims] 1. A non-elastic polyester crimped short fiber aggregate is used as a matrix and has a density of 0.005 to 0.2 g / cm.
^{3. In} the cushion structure having a thickness of 5 mm or more, in the short fiber aggregate, a thermoplastic elastomer having a melting point of 40 ° C. or more lower than the melting point of the polyester polymer forming the short fibers and an inelastic polyester are used. In the former, at least the elastic composite fibers exposed on the surface of the fibers are dispersed and mixed, and at that time, in the cushion structure, (A) the elastic composite fibers are formed by heat fusion with each other in an intersecting state. Flexible heat fixing point, and (B)
Flexible elastic fixing points formed by heat fusion in a state where the elastic composite fibers and the non-elastic polyester short fibers are interspersed, and the fibers in at least one surface layer of the cushion structure are A cushion structure characterized in that a smooth oil agent is attached to the surface of the fiber. 2. The cushion structure according to claim 1, wherein the thermoplastic elastomer is a thermoplastic polyester elastomer. 3. The cushion structure according to claim 1, wherein the smoothing oil agent is a silicone oil agent. 4. The cushion structure according to claim 1, wherein a smooth oil agent is adhered to the surface of the fiber throughout. 5. A layer in which a smooth oil agent is attached to the fiber surface,
Different from the layer where the smooth oil is not attached to the fiber surface 2
The cushion structure according to claim 1, which is formed of layers.