JPH0432675B2 - - 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. In addition, palm lock has a large specific gravity and easily sag, and there are 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. Therefore, an object of the present invention is to obtain a cushion body that is lightweight, has excellent air permeability, has a good surface condition, is resistant to deterioration, and has high hardness per specific gravity, and to efficiently manufacture such a cushion body. The goal is to enable manufacturing. [Means for Solving the Problems] The cushion body of the present invention is made of a sheet-like material in which fibers are intertwined three-dimensionally and the intertwining points of the fibers are bonded with a thermosetting urethane binder. A cushion body is provided continuously over at least one surface and a side surface, and on the inside of this sheet-like material, fibers are intertwined three-dimensionally and the intertwining points of the fibers are bonded with a thermosetting urethane binder. It is packed with
The cushion main body and the sheet-like material are bonded to each other by the binder. As a binder, NCO is used at the end.
Urethane binders having groups are preferred. The above-mentioned cushion body is resistant to fading because the fibers of the cotton-like intertwined fiber aggregates that make up the sheet material and the cushion body are oriented in all directions and are bonded by a thermosetting urethane binder. Excellent breathability. Also, since it has greater hardness per specific gravity than palm lock or urethane foam, a lightweight cushion body can be obtained. The method of the present invention also includes a step in which a sheet-like material in which fibers are three-dimensionally entangled and impregnated with a thermosetting urethane binder liquid is placed on the inner surface of a mold by suction to give it a shape; A step of excessively impregnating cotton for the ivy cushion body with a thermosetting urethane binder liquid, a step of removing excess liquid from the impregnated cotton, and a step of stuffing the impregnated cotton inside the sheet-like material. The present invention is characterized by comprising the step of curing the binder by blowing heated steam into the mold, and integrally molding the cushion body made of the cotton and the binder with the sheet-like material. The above-mentioned fibers may be only organic synthetic fibers such as polyester, but may contain inorganic fibers such as metal or glass as necessary. 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. Moreover, in the method of the present invention, a sheet-like material made of a fiber aggregate to which a binder is attached is spread on the inner surface of a mold by suction to impart a shape, so that it can be efficiently set in a mold. Example 1 Polyester cotton (Toyobo, product name S-up)
6d x 64mm, hollow conjugate type) is thoroughly opened using a fiber opening machine, and then a sheet-like product with a thickness of about 10 to 40 mm is made. Also, a plurality of block-shaped fiber aggregates are made using similar fibers. 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. Urethane prepolymers (Mitsui Nisso Urethane,
NCO% synthesized from MN3050 and T-80 = 5±
0.2%)/triclene solution (prepolymer concentration 1-70 wt%). 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. Thereafter, as illustrated in FIG. 1, the sheet-like material 2 is placed on top of the mold 1, and as shown in FIG. The shape of mold 1 is given by laying it on the inner surface of the mold. In this case, the sheet-like material 2 is cut in advance to a size that is continuous across the front side (lower side in the drawing) and side surface of the cushion body. Next, as shown in FIG. 3, the plurality of block-shaped fiber aggregates 5 for the cushion body are placed on the inner surface side of the sheet-like material 2, and compressed by a pressure plate 7 from the upper part of the mold 1. Apply vibration to ensure that the voids in mold 1 are sufficiently filled with polyester cotton.
Then mold 1 is closed. The sheet-like material 2 and the fiber aggregate 5 for the cushion body packed in the mold 1 are heated at 80 to 130°C.
A cushion body is obtained by blowing in steam in an amount equal to or more than NCO, curing with steam for 3 minutes, and then demolding. FIG. 5 shows a flowchart of the above manufacturing process. Example 2 The same polyester cotton as in Example 1 is sufficiently opened using a fiber opening machine, and then a sheet-like product having a thickness of about 10 to 40 mm is produced. A large number of spherical fiber aggregates each weighing about 0.02 to 1.0 g are also made using similar fibers. The above sheet-like and spherical fiber aggregates are impregnated with an excessive amount of the same urethane prepolymer/triclene solution as in Example 1, and the solution is removed to a predetermined amount by centrifugal force. Thereafter, the sheet-like material 2 is placed on the mold 1 as shown in FIG. 4, and the shape of the mold 1 is given to the sheet-like material 2 by suction force. Then, the above-mentioned large number of spherical fiber aggregates 5' are packed inside the sheet-like material 2. In this case, the spherical fiber aggregates 5' may be packed into the mold 1 by air flow. Next, the pressure plate 7 applies compression and vibration to the mold 1.
Ensure that the voids inside are sufficiently filled with polyester cotton. By compressing while applying vibration in this manner, the degree of entanglement of each spherical fiber aggregate 5' can be increased. Then mold 1 is closed. The sheet-like material 2 and the fiber aggregate 5' for the cushion body packed in the mold 1 are heated at 80 to 130°C.
A cushion body was obtained by blowing in steam in an amount equal to or more than NCO, curing with steam for 3 minutes, and then demolding. FIG. 5 shows a flowchart of the above manufacturing process. Example 3 Using polyester cotton having the same material and shape as in Examples 1 and 2, a sheet-like material and a block-like or spherical fiber aggregate are made. These polyester cottons were coated with the same urethane prepolymer as in Examples 1 and 2.
Impregnate with trichlene solution and remove the solution by centrifugal force. An upper mold and a lower mold are prepared, and the sheet-like polyester cotton is placed on both the upper mold and the lower mold, respectively, and the shape of the mold is given by the suction force of a blower or a vacuum pump. These two sheet-like materials are cut to a size that can cover both the front and back surfaces and sides of the cushion body. Then, as in Examples 1 and 2, a block-shaped or small spherical fiber aggregate is stuffed inside the sheet-like material, the mold is closed, and the binder is cured to form the material. According to Example 3, a cushion body whose entire circumference is covered with two sheet-like materials can be obtained. Embodiment 4 Embedded members such as metal frame lines, suspension lines, and springs are set in the mold as necessary. Thereafter, in the same manner as in Example 1, a sheet of polyester cotton impregnated with urethane prepolymer was placed in a mold, and the shape of the mold was given by suction force.
A block-shaped or spherical fiber aggregate impregnated with urethane prepolymer is packed into a punched metal mold and cured with steam. In addition,
In the case of this embodiment, after the sheet-like material is placed in a mold and given a shape by suction, embedded members such as hanging wires may be set in the mold. According to this fourth 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 the cushion bodies obtained in each of the above examples, the polyester fibers of the fiber aggregate are intertwined with each other in a three-dimensional manner, and the surfaces of the fibers are coated with a urethane resin binder, and at the intersections of the fibers, The fibers are bonded together with a binder. Moreover, at least one of the front and back surfaces and side surfaces of the cushion body are covered with sheet-like polyester cotton, and the fibers of this sheet-like material 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 Examples 1 to 4 and Comparative Examples 1 to 3. In addition, the details of Comparative Examples 1 to 3 will be described later. In addition, FIG. 6 shows Example 1 and Comparative Examples 1-
3 shows the relationship between density and hardness.

[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)

〔Effect of the invention〕

According to the present invention, it is possible to obtain a cushion body that is lighter than the conventional cushion body, has breathability, is resistant to flattening, and has a comfortable ride. Moreover, a cushion body with good appearance, particularly good surface condition, can be obtained. In addition, the manufacturing equipment, molds, and work processes are simple, and the cushion body in which the embedded member is integrally molded can be efficiently manufactured.

[Brief explanation of drawings]

1 to 3 are schematic diagrams showing a part of the steps according to an embodiment of the present invention in the order of the steps, and FIG.
The figure is a schematic diagram showing a part of the process according to another embodiment of the present invention, Figure 5 is a process explanatory diagram showing an embodiment of the method of the present invention, and Figure 6 is a diagram showing the relationship between density and hardness of a cushion body. It is a diagram. 1... Mold, 2... Sheet-like material, 5... Block-shaped fiber aggregate, 5'... Spherical fiber aggregate, 7... Pressure plate.

Claims (1)

[Claims] 1. A sheet-like material in which fibers are three-dimensionally entangled and the intertwining points of the fibers are bonded with a thermosetting urethane binder is spread over at least one of the front and back surfaces and side surfaces of the cushion body. In addition to being provided continuously, the inside of this sheet-like material is filled with a cushion body in which fibers are intertwined three-dimensionally and the intertwining points of the fibers are bonded with a thermosetting urethane binder. and the sheet-like material are adhered to each other by the binder. 2. A process in which a sheet-like material in which fibers are intertwined in a three-dimensional manner and impregnated with a thermosetting urethane binder liquid is placed on the inner surface of a mold by suction to give it a shape, and a A process of excessively impregnating cotton with a thermosetting urethane binder liquid, a process of removing excess liquid from the impregnated cotton, a process of packing the impregnated cotton inside the sheet-like object, and a process of heating the cotton with heated steam. A method for manufacturing a cushion body, comprising the step of curing the binder by blowing the binder into a mold, and integrally molding the cushion body made of the cotton and the binder with the sheet-like material. 3. The method of manufacturing a cushion body according to claim 2, wherein the impregnated cotton of the cushion body is stuffed inside the sheet-like material, and then the impregnated cotton is compressed using a pressure plate. 4. The method of manufacturing a cushion body according to claim 3, wherein the impregnated cotton is compressed while applying vibration to the pressure plate.