JPH0432674B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field of the Invention] The present invention relates to a cushion body used for vehicle seats, bedding, furniture, etc., and a manufacturing method thereof. [Prior Art] Conventionally, various materials have been used for cushion bodies. For example, synthetic resin foams such as palm locks and urethane foams using woven fibers have been used, and cushion bodies using natural fibers or organic synthetic fibers such as cotton have been proposed. In addition, as a type of cushion body made of synthetic fiber cotton, polyester fibers are mixed with low-melting binder fibers, packed in a mold, and then hot air with a temperature higher than the melting point of the binder fibers is blown to melt the binder fibers. Some products are then cooled to solidify the binder and bond the polyester fibers together. [Problems to be Solved by the Invention] However, all of these conventional products have drawbacks.
For example, urethane foam has poor breathability and tends to get stuffy, making it difficult to ride comfortably. Additionally, the use of toxic substances such as amine compounds and toluene diisocyanate creates a poor working environment during production. Moreover, some produce toxic gases when burned. Currently, high-modulus urethane foam (HR foam) is said to provide a good ride, but this has the disadvantage of being considerably denser than general urethane foam. Furthermore, bermlock has a large specific gravity, is easily set, and has problems with the stability of raw material supply. Cotton, which is made of organic synthetic fibers or natural fibers, has a large settiness and is expensive, and it takes time and effort to integrally mold embedded parts such as frame lines. Furthermore, cushion bodies made of synthetic fibers with a high melting point and binder fibers with a low melting point are expensive due to poor productivity, and have the disadvantage of being weak against high heat and prone to sagging. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a cushion body that has excellent air permeability, is resistant to collapse, has high hardness per specific gravity, and has no directionality in hardness, and a method for manufacturing the same. [Means for Solving the Problems] The cushion body of the present invention has a spherical fiber aggregate in which fibers are three-dimensionally intertwined, and the intertwining points of the fibers are bonded with a thermosetting urethane binder, and a large number of these It is characterized in that the spherical fiber aggregates are bonded to each other with the binder and molded into a predetermined shape, and the fibers are oriented in all directions. As a binder, NCO is used at the end.
Urethane binders having groups are preferred. The above-mentioned cushion body has excellent air permeability because the fibers of the spherical fiber aggregates intertwined in a cotton-like manner are oriented in all directions and bonded by a binder. Also, since it has greater hardness per specific gravity than palm lock or urethane foam, a lightweight cushion body can be obtained. Furthermore, the method of the present invention can be applied to a large number of spherical fiber aggregates made of 3-dimensionally entangled organic synthetic fibers or a large number of spherical fiber aggregates made of a 3-dimensionally entangled mixture of inorganic fibers and organic synthetic fibers. After excessive impregnation with a thermosetting urethane binder liquid and removing the excess liquid, the binder is attached to the intertwined points of the fibers, and these spherical fiber aggregates are introduced into the mold with a flow of air. , is characterized by blowing heated steam into a mold to harden the binder and mold it into a predetermined shape.
Polyester fibers, nylon fibers, polypropylene fibers, acrylic fibers, etc. are used as the organic synthetic fibers. Further, inorganic fibers such as metal and glass may be included in the organic synthetic fibers. According to the method of the present invention, almost no pressure is applied to the mold, so reinforcement of the mold is unnecessary or only slight.
A simple mold with ventilation such as wire mesh or perforated metal can also be used. Therefore, the mold is simple, lightweight, and inexpensive. Furthermore, in the method of the present invention, a binder is attached to spherical fiber aggregates and these spherical fiber aggregates are introduced into a mold together with a flow of air, so that molds with complex shapes can be easily packed. Therefore, cushion bodies with complicated shapes can be produced efficiently. Example 1 Polyester cotton (Toyobo, product name S-up)
6d x 64mm, hollow conduit type) is fully opened with a fiber opening machine, and the weight is approximately 0.02 to 1.0
Make it into a g sphere. Note that the hollow conjugate type is made by crimping two types of polyester with different heat shrinkage rates, and is hollow inside. However, solid type fibers may also be used. The above spherical fiber aggregate is impregnated with an excessive amount of urethane prepolymer (Mitsui Nisso Urethane, NCO%=5±0.2% synthesized from MN3050 and T-80)/triclene solution (prepolymer concentration 1
~70wt%). The solution is removed to a predetermined amount by centrifugal force.
The centrifugal force is about 50 to 1000 m/sec ² and the weight ratio of cotton to urethane is about 9:1 to 5:5. After that, as illustrated in FIG.
, the spherical fiber aggregate A is sucked and packed into a punching metal mold 2 with a flow of air.
Close lid 3. Then, 80
A cushion body is obtained by blowing steam of up to 130° C. in an amount equivalent to NCO or more, and curing with steam for 3 minutes, followed by demolding. FIG. 3 shows a flowchart of the above manufacturing process. Example 2 Using the same method as in Example 1, a spherical fiber aggregate to which urethane prepolymer was attached was packed into a punching metal mold with air flowing through suction, and as shown in Figure 2, a large number of small holes were formed. The opened pressure plate 5 compresses while applying vibration. Thereby, the voids in the mold 2 can be sufficiently filled with spherical fiber aggregates A, and the degree of entanglement of each fiber aggregate A can be increased. Thereafter, water vapor of 80 to 130° C. in an amount equal to or more than NCO is blown into the material, and after curing with water vapor for 3 minutes, the material is demolded to obtain a cushion body. Embodiment 3 Embedded members such as metal frame lines, suspension lines, and springs are set in the mold as necessary. Thereafter, in the same process as in Example 1, the spherical fiber aggregate to which the urethane prepolymer was attached was packed into a punching metal mold with a suction-induced air flow, and hardened with water vapor. According to this third embodiment, it is possible to easily obtain a cushion body in which embedded members such as a frame line and a suspension line are integrated. Note that polyester cotton with a fineness of 1 to 50 d (denier), a fiber length of 25 to 150 mm, and a number of crimps of 3 to 25/inch can be used. Furthermore, a spherical fiber aggregate may be formed by a mixture of inorganic fibers and organic synthetic fibers, or a spherical fiber aggregate consisting only of inorganic fibers and a spherical fiber aggregate consisting only of organic synthetic fibers may be mixed. It may also be used as The urethane prepolymer has a functional group number of 2.5 to 8,
Molecular weight (per OH) 200-2500, EO (ethylene/
oxide) addition amount 0 to 20wt%, terminal NCO = 2
~30% can be used. Further, the solvent is a halogenated hydrocarbon such as trichlene. Other solvents are flammable and difficult to use. As the curing agent, in addition to water, amine water, amine compounds, compounds containing active hydrogen such as hydroxyl groups, etc. can be used. Both the lower mold and the upper mold are breathable molds such as wire mesh or punched metal, and the curing time can be shortened by blowing steam from the outside of the mold. In each of the cushion bodies obtained in the above examples, the polyester fibers of the spherical fiber aggregate are three-dimensionally entangled with each other, and the surfaces of the fibers are coated with a urethane resin binder, and the intersections of the fibers are coated with a urethane resin binder. In the step, the fibers are connected to each other with a binder. Moreover, these many spherical fiber aggregates are also bonded to each other with a binder. Each fiber is oriented randomly in all directions. Urethane binders have strong adhesive strength and excellent heat resistance, and because they use water as a curing agent (crosslinking agent), they are easy to work with and are safe. Table 1 below shows the physical properties of Example 1 and Comparative Examples 1 to 3. Note that the details of Comparative Examples 1 to 3 will be described later. In addition, FIG. 4 shows Examples 1 and 2 and Comparative Examples 1 to 4.
3 shows the relationship between density and hardness.

【table】

[Table] Comparative Example 1 A polyether polyol with a molecular weight of 3000 and a functional group number of 3 and toluene diisocyanate (T-
80), water as a blowing agent, and other auxiliary agents are stirred with a mixing head, then poured into a temperature-controlled mold in a predetermined amount, and the mold is closed. Thereafter, the mold was heated at 170°C for 10 minutes (5 minutes for HR foam) to harden the urethane foam, and then removed from the mold. In addition, when adding a flame retardant, add 10 to 20 parts of the flame retardant. (Detailed prescription examples are shown in Table 2)

【table】

[Table] Comparative Example 2 Latex is sprayed onto loosened palm fibers, compressed to a predetermined thickness, and dried with hot air at 120°C. This is cut to a predetermined size, laminated and placed in a mold so as to have a predetermined density. Then spray the latex again. After closing the mold, it was dried with hot air at 120°C and removed from the mold to obtain a palm lock. Comparative example 3 Polyester cotton (6d, hollow conjugate)
In, low melting point binder fiber (4D, melting point 110℃)
The mixture was blended and opened at a weight ratio of 7:3 to form a sheet with a thickness of 20 mm. This is cut into a predetermined shape, laminated and placed in a mold so as to have a predetermined density. Thereafter, the low melting point binder fibers are melted with hot air at a temperature equal to or higher than the melting point of the binder fibers. After the low melting point binder fibers were solidified by cooling, they were removed from the mold to obtain a cushion body made of high melting point fibers and a low melting point binder. The cushion body of the present invention is suitable for vehicle seats, but can of course also be used for furniture, bedding, etc. [Effects of the Invention] According to the present invention, it is lighter than conventional products, has greater hardness per specific gravity, has greater load strength against loads in all directions, and is breathable, making it difficult to buckle and providing a comfortable ride. A cushion body is obtained. Furthermore, the manufacturing equipment, molds, and work processes are simple, and cushion bodies with complicated shapes can be manufactured efficiently.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an apparatus for carrying out the method of the present invention;
Fig. 2 is a schematic diagram of another apparatus for implementing the method of the present invention, Fig. 3 is a process explanatory diagram showing an example of the method of the present invention, and Fig. 4 is a diagram showing the relationship between density and hardness of a cushion body. be. A... Spherical fiber aggregate.

Claims (1)

[Scope of Claims] 1. The intertwining points of the fibers of a spherical fiber aggregate in which fibers are three-dimensionally intertwined are bonded with a thermosetting urethane binder, and a large number of these spherical fiber aggregates are bonded to each other with the binder. 1. A cushion body which is formed into a predetermined shape in a bonded state, and wherein the fibers are oriented in all directions. 2 A thermosetting type is applied to a large number of spherical fiber aggregates made of three-dimensionally entangled organic synthetic fibers, or a large number of spherical fiber aggregates made of a three-dimensionally entangled mixture of inorganic fibers and organic synthetic fibers. After excessive impregnation with urethane binder liquid, the binder was attached to the intertwined points of the fibers by removing the excess liquid, and these spherical fiber aggregates were introduced into a mold with a flow of air, and then heated. A method of manufacturing a cushion body, which comprises blowing water vapor into a mold to harden the binder and molding it into a predetermined shape. 3. A method for manufacturing a cushion body according to claim 2, characterized in that the spherical fiber aggregate is introduced into a mold together with a flow of air, and then the spherical fiber aggregate is compressed using a pressure plate. . 4. The method of manufacturing a cushion body according to claim 3, wherein the spherical fiber aggregate is compressed while applying vibration to the pressure plate.