JP2010029276A - Seat pad and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a bending deformation noise from happening in a reinforcing cloth integrated type seat pad. <P>SOLUTION: A seat pad 1 includes a pad body 2 consists of a resin foaming body and a reinforcing cloth 3 which is integrated into the back face of the pad body 2. The reinforcing cloth 3 has a first layer 3a which includes a binder and a second layer 3b which either includes no binders or includes less amount of binders than the first layer, and the second layer 3b is arranged at the pad body 2 side. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a seat pad installed in a vehicle or the like, and more particularly to a seat pad in which a reinforcing cloth is integrated on the back surface of a pad body. The present invention also relates to a method for manufacturing the seat pad.

  As a vehicle seat pad, a pad body made of polyurethane foam and a cover material made of a skin material made of leather or cloth is used.

  Since the back surface of the seat pad rubs against the support member due to the swing of the vehicle or the movement of the body such as an occupant, the pad body alone is easily damaged. Therefore, a reinforcing cloth may be provided on the back surface of the seat pad.

  Since this reinforcing cloth protects the pad body from damage, it is formed integrally with the pad body so as not to be displaced or peeled from the pad body. That is, in the foam molding process for manufacturing the seat pad, a method is adopted in which resin is injected and foamed into the mold with the reinforcing cloth set in advance on the inner surface of the mold, and the pad body is molded and the reinforcing cloth is integrated at the same time Yes.

Since the back surface of the seat pad has a complicated shape, a cloth formed by sewing so as to match a large number of small pieces to the shape has been conventionally used as a reinforcing cloth. However, not only a great deal of labor and time is required for cutting and sewing, but also it is difficult to obtain a reinforcing fabric that accurately conforms to the shape of the inner surface of the mold. Therefore, there is a case where a shaped reinforcing cloth obtained by molding a nonwoven fabric into a shape of a mold cavity surface with a mold is used (Patent Document 1).
JP 2006-281768 A

  In order to shape the nonwoven fabric, a binder is contained in the nonwoven fabric, and the nonwoven fabric is heated along the shaping mold. Therefore, the shaped nonwoven fabric contains a binder, and the shaped nonwoven fabric itself has a certain degree of hardness and rigidity. When the reinforcing fabric made of this shaped nonwoven fabric is set on the cavity surface and urethane foam molding is performed, urethane is impregnated into the reinforcing fabric, and the hardness and rigidity of the reinforcing fabric are further increased. When an occupant sits on a seat pad with such a hard and rigid reinforcing cloth on the back and a large load is locally applied to the reinforcing cloth, the load-loading portion of the reinforcing cloth is deformed to be bent. , “Peko” may cause annoying bending deformation sound.

  An object of this invention is to prevent generation | occurrence | production of the bending deformation sound in the sheet | seat pad of reinforcement cloth integral type.

  The seat pad according to claim 1 is a seat pad having a pad main body made of a resin foam and a reinforcing cloth integrated on a back surface of the pad main body. The reinforcing cloth includes a first layer containing a binder and a binder. And a second layer having a binder content lower than that of the first layer, and the second layer is disposed on the pad body side.

  The seat pad of claim 2 is characterized in that, in claim 1, the second layer does not contain a binder.

  According to a third aspect of the present invention, the seat pad according to the first or second aspect is characterized in that the reinforcing cloth is composed of only the first layer and the second layer.

  According to a fourth aspect of the present invention, there is provided a seat pad according to any one of the first to third aspects, wherein the reinforcing fabric is made of a non-woven fabric.

  According to a fifth aspect of the present invention, the seat pad according to any one of the first to fourth aspects is characterized in that the pad main body is made of polyurethane foam.

  The seat pad of claim 6 is characterized in that, in claim 5, the polyurethane foam is impregnated only in the second layer.

  A method for manufacturing a seat pad according to claim 7 is a method for manufacturing a seat pad according to any one of claims 1 to 6, wherein the reinforcing cloth is formed so that the first layer is in contact with a mold. And a step of forming the pad main body in which the reinforcing cloth is integrated by foaming a stock solution for foamed resin in the mold. It is.

  In the seat pad of the present invention, the reinforcing cloth integral with the pad main body has a first layer containing a binder and a second layer containing no binder or a low binder content, and the second layer is on the pad main body side. It is arranged so that.

  The foamed resin forming the pad body impregnates the second layer, but does not impregnate or hardly impregnate the first layer. For this reason, the hardness and rigidity of the second layer are increased by the impregnation of the resin, but the hardness and rigidity of the first layer are not or hardly increased. As a result, when the reinforcing cloth is deformed together with the pad main body, it is deformed flexibly and no bending deformation sound is generated.

  By making the second layer a binder-free layer, the hardness and rigidity of the second layer after the resin impregnation are suppressed, and the occurrence of bending deformation sound is prevented.

  It is preferable that the reinforcing cloth is composed of only the first layer and the second layer because the configuration is simple.

  Nonwoven fabric is suitable as a constituent material of the reinforcing fabric. The pad body is preferably made of polyurethane foam. By impregnating only the second layer with this polyurethane foam and not impregnating the first layer, the hardness and rigidity of the first layer are suppressed, and the occurrence of bending deformation sound is prevented.

  Hereinafter, embodiments will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a vehicle seat pad 1 according to an embodiment.

  The vehicle seat pad 1 includes a pad main body 2 made of urethane foam or the like, and a reinforcing cloth 3 integrated on the back surface of the pad main body 2. The reinforcing cloth 3 is made of a non-woven fabric and includes a first layer 3a containing a binder and a second layer 3b containing no binder. The second layer 3b is disposed on the pad body 2 side. Urethane or the like is preferably impregnated only in the first layer 3a.

  The back surface of the vehicle seat pad 1 is fixed to a metal frame (not shown). At this time, since the reinforcing cloth 3 is interposed between the pad main body 2 and the metal frame, the pad main body is prevented from being damaged, and the pad main body 2 and the metal frame directly rub against each other. Generation of (rub sound) is prevented. Further, as will be described in detail later, the hardness and rigidity of the reinforcing cloth 3 are not excessive, and no bending deformation sound is generated.

  Next, a method for manufacturing the vehicle seat pad 1 will be described.

  FIG. 2 is a cross-sectional view for explaining an example of a method for manufacturing the vehicle pad 1. In FIG. 2, the mold 10 is composed of a lower mold 10a and an upper mold 10b. In the figure, reference numeral 11 denotes a cavity.

  The reinforcing cloth 3 is held on the inner surface of the upper mold 10b such that the first layer 3a is in contact with the mold and the second layer 3b side is the cavity side. The reinforcing cloth 3 is attached to the upper mold 10b using a double-sided tape, a magnet tape, or the like. Next, a raw material for flexible foam such as a urethane stock solution is supplied into the cavity 11, and the mold is closed and foamed. Thereafter, the sheet pad 1 in which the reinforcing cloth 3 and the pad main body 2 are integrated is obtained by removing the mold.

  In the foam molding, a foam material such as urethane impregnates the second layer 3b, but does not impregnate the first layer 3a at all or almost. As a result, the hardness and rigidity of the first layer 3a are not increased or hardly increased by foam molding. The second layer 3b is increased in hardness and rigidity by impregnation with the foam material, but since the second layer 3b does not contain a binder, even if the hardness and rigidity are increased, the hardness and rigidity are so high. It will not be.

  As described above, the reinforcing cloth 3 does not have such a high hardness and rigidity even after foam molding, so that no bending deformation sound is generated even when the occupant is seated.

  Next, suitable materials for the pad main body 2, the reinforcing cloth 3, and the binder will be described in detail.

<Pad body 2>
The pad body 2 is preferably made of polyurethane foam. The polyurethane foam stock solution is a polyurethane foam blend mainly composed of polyol and isocyanate.

  Examples of the polyol include dihydric to hexavalent polyhydric alcohols, polyoxyalkylene polyols (polyether polyols), polyester polyols, polymer polyols, and the like. Of these, polyether polyols and polyester polyols are preferably used, and polyether polyols are particularly preferably used. These polyols may be used alone or in combination of two or more.

  Known isocyanates can be used as the isocyanate. For example, tolylene diisocyanate, diphenylmethane diisocyanate, triphenyl diisocyanate, xylene diisocyanate, polymethylene polyphenylene polyisocyanate, hexamethylene diisocyanate, isophorone diisocyanate and the like can be mentioned, and these can be used alone or in combination of two or more. May be.

  From the viewpoint of adjusting (increasing) the hardness of the polyurethane foam molded article, a crosslinking agent can also be blended in the polyurethane foam blend. Examples of such cross-linking agents include trimethylolpropane, diethylene glycol, sucrose (sugar), pentaerythritol, 1,4-butanediol, dipropylene glycol, ethylenediamine, glycerin, etc., and PO or EO added thereto. And alkylene oxide homopolymers (EO homopolymers and PO homopolymers). In particular, when an EO homopolymer is used as a cross-linking agent, it is possible to moderately suppress the initial reaction when the polyurethane foam compound is foam-cured, and the liquid spreads and foams to every corner in the mold. As a result of the stock solution being easily spread, abnormalities in the outer shape of the molded product (such as “chips” at the corners) are less likely to occur.

  In the polyurethane foam formulation, a foaming agent, a catalyst, a foam stabilizer and the like can be blended as necessary in the same manner as in a normal polyurethane foam formulation.

  As the foaming agent, water is suitable, but low boiling point compounds such as methylene chloride and monofluorotrichloromethane can also be used.

  As the catalyst, for example, amine-based and tin-based catalysts are preferably used.

  Examples of the foam stabilizer include organopolysiloxanes, alkyl carboxylates, and alkylbenzene sulfonates.

As the nonwoven fabric constituting the reinforcing fabric, nonwoven fabrics of various synthetic fibers are suitable. The nonwoven fabric of the first layer 3a and the nonwoven fabric of the second layer 3b may be the same type or different types. The basis weight of the first layer 3a is preferably 50 to 80 g / m ^2, particularly about 60 to 80 g / m ² . The basis weight of the second layer 3b is preferably about 50 to 80 g / m ^2, particularly about 60 to 80 g / m ² .

  The first layer 3a contains a binder. The binder adhesion amount of the first layer is preferably 30 to 60% (% by weight, hereinafter the same), particularly about 30 to 40%.

  The second layer preferably does not contain a binder, but may contain a small amount of binder.

  The reinforcing cloth 3 is preferably composed only of the first layer and the second layer, but may have a third layer between the first layer and the second layer. As this 3rd layer, what has less binder content than the 1st layer 3a and more than the 2nd layer 3b is illustrated. The third layer may be provided not only in one layer but also in two or more layers.

  The first layer 3a, the second layer 3b, and the third layer interposed as necessary are integrated by a needle punch or the like.

  In order to shape the reinforcing cloth 3, the raw material sheet of the reinforcing cloth 3 may be placed along a shaping mold and heated.

  Examples of the binder contained in the first layer 3a and the like include granular thermoplastic resins and low melting point fibers. In addition, the nonwoven fabric containing a low melting point fiber as a binder further contains a high melting point fiber.

  As the granular thermoplastic resin, it is preferable to use a granular hot melt adhesive resin (adhesive). For example, there are polyamide resin, polyester resin, polyvinyl chloride resin, polyethylene resin, polyethylene vinyl acetate resin, polyurethane resin, polyvinyl alcohol resin, polybutyral resin, and the like, and a mixture thereof may be used. The melting point is preferably 70 to 100 ° C. The particle size of the granular hot melt adhesive is preferably 200 μm or less, and the particle size distribution may be changed as necessary.

  The following materials can be used as the nonwoven fabric composed of low-melting fibers and high-melting fibers.

  As the low melting point fiber, one having a melting point lower than that of the high melting point fiber and having a specific softening point and melt viscosity is used. Specifically, hot-melt adhesive fibers that can be mixed with high-melting fibers and heated to a temperature lower than the melting point of the high-melting fibers to melt and melt the high-melting fibers are used. The thickness of the fiber used is preferably about 1.5 to 10 d (denier).

  Examples of such low-melting fibers include thermoplastic fibers such as polyester, polyethylene, polypropylene, acrylic, nylon, polyvinyl alcohol, and polyvinyl chloride. These fibers may be used alone or in combination with a high melting point fiber such as a conjugate type or a core-sheath type structure. The fineness and fiber length of the low melting point fiber are not particularly limited. The melting point of the low melting point fiber is preferably about 100 to 160 ° C. (or the softening point is about 80 to 140 ° C.).

  Examples of the high melting point fiber include polyester, polypropylene, acrylic, and nylon. The fineness and fiber length of the high melting point fiber are not particularly limited. The melting point of the high melting point fiber may be 180 ° C. or higher (or the softening point is 160 ° C. or higher). Further, the difference in melting point (or difference in softening point) between the low melting point fiber and the high melting point fiber is preferably 50 ° C. or more.

  The mixing ratio of the low melting point fiber and the high melting point fiber is preferably 20 to 70% by weight of the low melting point fiber and 30 to 80% by weight of the high melting point fiber. When the mixing ratio of the low-melting fiber is less than 20% by weight, there are fears that the fused portion is reduced and desired rigidity cannot be obtained. Further, when the mixing ratio of the low melting point fiber is more than 70% by weight, the rigidity is remarkably increased, so that not only the mold release from the mold becomes difficult, but also the sheet surface after molding becomes plastic and the fiber does not remain. When used as a pad reinforcing cloth, rubbing noise is likely to occur.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples.

Example 1
The vehicle seat pad 1 was manufactured using the reinforcing cloth 3 containing the binder only in the first layer 3a. That is, as shown in FIGS. 1 and 2, the shaped reinforcing cloth 3 was arranged on the inner surface of the upper mold 10b so that the second layer 3b was on the cavity 11 side. Next, the lower mold 10 a and the upper mold 10 b were combined, and a urethane foam raw material was supplied into the cavity 11 to perform foam molding. Thereafter, the vehicle was removed from the mold to obtain a vehicle seat pad 1 in which the reinforcing cloth 3 and the pad main body 2 were integrated.

As the first layer 3a and the second layer 3b, Tafnel ESE323 (weight per unit area 80 g / m ² ) was used.

  The adhesion amount of the binder contained in the first layer 3a was 40%.

  As the raw material for the light foam, a mixture of 100 parts by mass of a polyol, a crosslinking agent, a catalyst, a foam stabilizer and water and 35 parts by mass of isocyanate was used.

  Further, in foam molding, the liquid temperature of this raw material was 25 ° C., and the temperature of the mold 10 was maintained at 60 ° C.

  When a person with a weight of 70 kg sat on the seat pad 1 formed as described above, no bending deformation sound was generated.

Example 2
A vehicle seat pad 1 was obtained in the same manner as in Example 1 except that the binder adhesion amount of the first layer 3a was 40%.

  When a person with a weight of 70 kg sat on the seat pad 1 formed as described above, no bending deformation sound was generated.

Comparative Example 1
A vehicle seat pad was manufactured in the same manner as in Example 1 except that the same amount of binder as that of the first layer 3a was adhered to the second layer 3b. When a person with a weight of 70 kg sat on the seat pad, a bending deformation sound was generated from the bottom of the buttocks.

  As is clear from the above, the vehicle seat pads of Examples 1 and 2 do not generate bending deformation sound even if the first layer of the reinforcing cloth contains a binder.

It is typical sectional drawing of the vehicle seat pad which concerns on embodiment. It is sectional drawing explaining an example of the manufacturing method of the vehicle seat pad of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle seat pad 2 Pad main body 3 Reinforcement cloth 3a 1st layer 3b 2nd layer

Claims (7)

In a seat pad having a pad body made of a resin foam and a reinforcing cloth integrated on the back surface of the pad body,
The reinforcing fabric has a first layer containing a binder and a second layer that does not contain a binder or has a lower binder content than the first layer,
The seat pad, wherein the second layer is disposed on the pad body side.   2. The seat pad according to claim 1, wherein the second layer does not contain a binder.   3. The seat pad according to claim 1, wherein the reinforcing cloth is composed of only the first layer and the second layer.   4. The seat pad according to claim 1, wherein the reinforcing fabric is made of a nonwoven fabric.   5. The seat pad according to claim 1, wherein the pad body is made of polyurethane foam.   The seat pad according to claim 5, wherein the polyurethane foam is impregnated only in the second layer. A method for manufacturing the seat pad according to any one of claims 1 to 6,
Disposing the reinforcing cloth on the cavity surface of the mold such that the first layer is in contact with the mold;
Forming a pad body in which the reinforcing cloth is integrated by foaming a foamed resin stock solution in the mold.

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