Abstract:
A mold that: makes it possible to manufacture a molded foam body wherein a reinforcing member extends to a portion of the outer face of the molded body main body that corresponds to a parting line in the inner face of the cavity of the mold; and prevents molding problems stemming from the reinforcing member getting into the aforementioned parting line. Also: a method for manufacturing a molded foam body using the aforementioned mold; and a molded foam body manufactured thereby. The aforementioned mold ( 1 ) is provided with a seal member ( 7 ) that seals the space between mating faces ( 2   a,    3   a ) of mold parts ( 2, 3 ) when the mold is fastened, and said seal member ( 7 ) is designed so as to be able to seal the space between the mating faces ( 2   a,    3   a ) even if the reinforcing member ( 22 ) gets in between the mating faces ( 2   a,    3   a ) on the cavity ( 4 ) side of the seal member ( 7 ).

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a mold for manufacturing a molded foam body in which a reinforcement member is disposed across at least a portion of an outer face of a molded body main body formed from a foamable synthetic resin, and the reinforcement member is integrated with the molded body main body, and relates in particular to a mold in which the molded body main body is molded, and the reinforcement member and the molded body main body are integrated together by foaming the foamable synthetic resin raw material inside a cavity, in a state in which the reinforcement member is disposed across an inner face of the cavity. The present invention also relates to a manufacturing method for a molded foam body using the mold, and a molded foam body manufactured by the manufacturing method. 
       BACKGROUND ART 
       [0002]    Seats, such as vehicle seats or household sofas, are configured using a seat pad formed from a foamable synthetic resin, such as a flexible polyurethane foam or a semi-rigid polyurethane foam. 
         [0003]    A reinforcement member is sometimes provided to an outer face of the seat pad in order to reinforce the seat pad (Patent Document 1).  FIG. 10  is a cross-section view illustrating a conventional example of a seat pad with a reinforcement member, and  FIG. 11  is a cross-section view illustrating a conventional example of a mold for manufacturing the seat pad with a reinforcement member. Note that  FIGS. 10 ,  11  respectively illustrate substantially the same content as FIGS. 1, 2 of Patent Document 1. 
         [0004]    A seat pad  120  as illustrated in  FIG. 10  includes a seat pad main body  121  formed from a foamable synthetic resin such as a polyurethane foam, and a reinforcement member  122  disposed across an opposite side face to a seating face of the seat pad main body  121  (hereafter referred to as the back face), and integrated with the seat pad main body  121 . The reinforcement member  122  is formed from a non-woven fabric or the like. 
         [0005]    A mold  101  as illustrated in  FIG. 11  includes an upper mold  102  and a lower mold  103 . The upper mold  102  and the lower mold  103  mate at respective peripheral edge portions. The symbol P in  FIG. 11  indicates a parting line formed by joining together the respective mating faces of the peripheral edge portions of the upper mold  102  and the lower mold  103 . The seat pad  120  (the seat pad main body  121 ) is molded with the seating face in a downward facing state inside a cavity  104  that is surrounded by the upper mold  102  and the lower mold  103 . Namely, the back face of the seat pad  120  is molded by the cavity inner face of the upper mold  102 , and the seating face and side peripheral faces of the seat pad  120  are molded by the cavity inner face of the lower mold  103 . 
         [0006]    When foam molding the seat pad  120 , the reinforcement member  122  is disposed across the cavity inner face of the upper mold  102 , and the reinforcement member  122  is fixed to the upper mold  102  by a fixing (not illustrated in the drawings) such as a pin or a magnet. Next, foamable synthetic resin raw material is supplied into the lower mold  103 , the mold is closed, and the raw material is foamed. The seat pad main body  121  is molded, and the seat pad main body  121  and the reinforcement member  122  are integrated together, by foamed synthetic resin formed by foaming raw material filling the inside of the cavity  104 . The seat pad  120 , with the reinforcement member  122  integrally provided to the back face, is obtained by opening and removing from the mold, after the foamed synthetic resin has cured. 
         [0007]    Patent Document 2 describes providing a seal member, such as packing, between the mating faces of each molding mold. 
       BACKGROUND ART 
       [0008]    Patent Document 1: Japanese Patent Application Laid-Open (JP-A) No. 2010-29276 Patent Document 2: JP-A No. 2009-285943 
       SUMMARY OF INVENTION 
     Technical Problem 
       [0009]    It is desirable that the reinforcement member  122  is disposed up to a terminal end of the outer peripheral side of the back face of the seat pad main body  121 , in order to evenly and sufficiently reinforce the seat pad  120  up to the terminal end side of the seating face thereof, and to make the outer edge portion of the reinforcement member  122  less liable to come away from the seat pad main body  121  due to deflection of the seat pad  120  when sat on, or the like. 
         [0010]    However, the parting line P is present on the inner face of the cavity  104  of the mold  101 , at a position corresponding to the terminal end of the outer peripheral side of the seat pad main body  121  back face. As a result, in cases in which the reinforcement member  122  is disposed up to the terminal end of the outer peripheral side of the seat pad main body  121  back face, a high level of attachment precision is required when attaching the reinforcement member  122  to the cavity inner face of the upper mold  102 , making manufacturing operations of the seat pad  120  burdensome. Namely, in such cases, the outer peripheral edge of the reinforcement member  122  needs to be aligned with the parting line P when attaching the reinforcement member  122  to the cavity inner face of the upper mold  102 . Suppose the attachment position of the reinforcement member  122  is misaligned, then there is a possibility of the reinforcement member  122  becoming trapped between the mating faces of the upper mold  102  and the lower mold  103  during mold fastening. In such cases, sealing at the parting line P after mold fastening becomes insufficient, with a possibility of molding defects occurring. 
         [0011]    Sometimes, as in Patent Document 2, a seal member, such as packing, is also provided between the respective mating faces of each molding mold. However, such a seal member is not conventionally configured to be capable of sealing between the mating faces even in a state in which the reinforcement member becomes trapped between the mating faces during mold fastening. 
         [0012]    As a result, as illustrated in  FIGS. 10 ,  11 , the reinforcement member  122  is conventionally designed to be somewhat smaller than the back face of the seat pad main body  121 , and the reinforcement member  122  is disposed such that the outer peripheral edge of the reinforcement member  122  is somewhat distanced from the parting line P, toward the center side of the cavity inner face, when attaching the reinforcement member  122  to the cavity inner face of the upper mold  102 . The attachment precision required when attaching the reinforcement member  122  to the cavity inner face of the upper mold  102  is accordingly reduced, enabling the manufacturing operation of the seat pad  120  to be made relatively simple, and also enabling relatively simple prevention of the reinforcement member  122  from becoming trapped between the respective mating faces of the upper mold  102  and the lower mold  103  during mold fastening. However, it is not possible to dispose the reinforcement member  122  up to the terminal end of the outer peripheral side of the seat pad main body  121  back face using this method. 
         [0013]    Note that there is also a possibility of molding defects caused by the reinforcement member  122  becoming trapped in the parting line P occurring in cases in which the reinforcement member  122  is disposed so as to straddle positions corresponding to the parting line P on the outer face of the molded body main body  121 . 
         [0014]    An object of the present invention is to provide a mold that enables manufacture of a molded foam body in which a reinforcement member is disposed up to a position on an outer face of a molded body main body corresponding to a parting line of a cavity inner face of the mold, and that enables prevention of molding defects caused by the reinforcement member becoming trapped in the parting line. A further object of the invention is to provide a manufacturing method of a molded foam body using the mold, and a molded foam body manufactured by the manufacturing method. 
       Solution to Problem 
       [0015]    A mold of a first aspect is a mold for manufacturing a molded foam body including a molded body main body comprising a foamable synthetic resin, and a reinforcement member disposed across at least a portion of an outer face of the molded body main body and integrated with the molded body main body, wherein: the mold includes at least two molding molds, a cavity surrounded by the molding molds is formed by fastening the molding molds together, and a parting line is formed by joining mating faces of each of the molding molds together at an inner face of the cavity; the mold includes a seal member that seals between the mating faces during mold fastening; when manufacturing the molded foam body, the reinforcement member is configured to be disposed across a cavity inner face of at least one of the molding molds prior to fastening the mold, and due to such placement, to be disposed inside the cavity so as to be adjacent to at least a portion of the parting line, the mold is then fastened, and the foamable synthetic resin raw material is foamed inside the cavity; the seal member is configured to be capable of sealing between the mating faces, even in a state in which the reinforcement member becomes trapped between the mating faces more to the cavity side than the seal member during mold fastening. 
         [0016]    A mold of a second aspect is the first aspect, wherein the seal member is provided around an entire periphery of the parting line. 
         [0017]    A mold of a third aspect is the first or second aspect, wherein a distance from the inner face of the cavity to the seal member is from 1 mm to 10 mm at at least a portion of the parting line that is disposed adjacent to the reinforcement member. 
         [0018]    A mold of a fourth aspect is any one of the first to the third aspects, wherein: the seal member comprises an elastic material; the seal member is configured attached to one mating face of the mating faces and protruding from the one mating face to another mating face side prior to mold fastening, such that a seal is made between the mating faces by the seal member pressing against the other mating face during mold fastening; the reinforcement member comprises a non-woven fabric with a basis weight of from 0.05 kg/m 2  to 0.2 kg/m 2 ; and a protrusion height of the seal member from the one mating face is from 0.2 mm to 1.5 mm prior to mold fastening. 
         [0019]    A mold of a fifth aspect is any one of the first to the fourth aspects, wherein a recessed step portion facing inside the cavity is provided at at least one of the mating faces, at at least a portion of the parting line that is disposed adjacent to the reinforcement member; the recessed step portion is configured such that the reinforcement member is able to escape inside the recessed step portion in a case in which the reinforcement member enters between the mating faces during mold fastening; and the seal member is disposed more to an opposite side from the cavity side than the recessed step portion. 
         [0020]    A manufacturing method of a molded foam body of a sixth aspect is a manufacturing method for manufacturing a molded foam body including a molded body main body formed from a foamable synthetic resin, and a reinforcement member disposed across at least a portion of an outer face of the molded body main body and integrated with the molded body main body, using the mold of any one of the first to the fifth aspects, the manufacturing method including: a reinforcement member placement process, in which the reinforcement member is disposed across the cavity inner face of at least one of the molding molds prior to fastening the mold, and when this placement is performed, the reinforcement member is disposed so as to be adjacent to at least a portion of the parting line inside the cavity; and a foam molding process, in which the mold is fastened after the reinforcement member placement process, and the foamable synthetic resin raw material is foamed inside the cavity. 
         [0021]    A manufacturing method for a molded foam body of a seventh aspect is the sixth aspect, wherein in the reinforcement member placement process, the reinforcement member is disposed such that an outer peripheral edge of the reinforcement member contacts the parting line, or such that a spacing between the outer peripheral edge of the reinforcement member and the parting line is 5 mm or less. 
         [0022]    A molded foam body of a eighth aspect is a molded foam body including a molded body main body formed from a foamable synthetic resin, and a reinforcement member disposed across at least a portion of an outer face of the molded body main body and integrated with the molded body main body, wherein the molded foam body is manufactured by the manufacturing method for a molded foam body of the sixth or the seventh aspect. 
         [0023]    A molded foam body of an ninth aspect is the eighth aspect, wherein the molded foam body is a seat pad. 
       ADVANTAGEOUS EFFECTS OF INVENTION 
       [0024]    When manufacturing the molded foam body with reinforcement member using the mold of the first aspect, the reinforcement member is disposed across a cavity inner face of at least one of the molding molds prior to fastening, and the reinforcement member is disposed so as to be adjacent to at least a portion of the parting line inside the cavity when this placement is performed. The mold is then fastened, and the foamable synthetic resin raw material is foamed inside the cavity. The a seal is made between the mating faces of each of the molding molds by the seal member during mold fastening. 
         [0025]    In the mold of the present invention, the seal member is configured so as to be capable of sealing between the mating faces, even suppose the reinforcement member becomes trapped between the mating faces more to the cavity side than the seal member during mold fastening. This enables molding defects of the molded body main body caused by the reinforcement member becoming trapped in the parting line to be reliably prevented. As a result, this enables manufacture of the molded foam body disposed with the reinforcement member up to a position on the molded body main body outer face corresponding to the parting line of the cavity inner face of the mold, without occurrence of molding defects of the molded body main body. 
         [0026]    As in the second aspect, the seal member is preferably provided around the entire periphery of the parting line. Such a configuration enables sufficient sealing by the seal member between the mating faces around the entire periphery of the parting line. 
         [0027]    In a seat pad employed as an general vehicle seat, for example, an acceptable range of attachment error of the reinforcement member is approximately 0 mm to 5 mm. In such cases, as in the third aspect, the distance from the inner face of the cavity to the seal member is preferably from 1 mm to 10 mm at at least the portion of the parting line that is disposed adjacent to the reinforcement member. Such a configuration enables molding defects of the molded body main body caused by the reinforcement member becoming trapped in the parting line to be more reliably prevented, even when attachment error of the reinforcement member occurs within the acceptable range. 
         [0028]    A configuration, as in the fourth aspect, in which a seal member comprising an elastic material is used, the seal member is configured attached to one mating face of the mating faces and protruding from the one mating face to another mating face side prior to mold fastening, such that a seal is made between the mating faces by the seal member pressing against the other mating face during mold fastening, is a relatively simple and preferable configuration. 
         [0029]    The protrusion height of the seal member from the one mating face of the molding mold prior to mold fastening (hereafter sometimes simply referred to as the protrusion height of the seal member) is suitably set according to the thickness of the reinforcement member used in the molded foam body. Note that, since it is generally difficult to unambiguously derive the thickness of the reinforcement member by actual measurement when a fabric material, such as a non-woven fabric, is used as the configuration material for the reinforcement member, it is preferable to set the protrusion height of the seal member according to the basis weight of the fabric material. Specifically, as in the fourth aspect, for example, in cases in which the reinforcement member is configured by a non-woven fabric with a basis weight of from 0.05 kg/m 2  to 0.2 kg/m 2 , the protrusion height of the seal member is preferably from 0.2 mm to 1.5 mm. Such a configuration enables sufficient sealing between the mating faces by the seal member, even when the reinforcement member enters between the mating faces of each of the molding molds at the parting line during mold fastening. 
         [0030]    In the fifth aspect, the recessed step portion facing inside the cavity is provided at the mating face of at least one of the molding molds, to at least the portion of the parting line adjacently disposed with the reinforcement member. The recessed step portion is configured such that the reinforcement member is able to escape inside the recessed step portion in a case in which the reinforcement member enters between the mating faces of the parting line during mold fastening. The seal member is disposed more to the opposite side from the cavity side than the recessed step portion. As a result, in cases in which the reinforcement member enters between the mating faces of the parting line during mold fastening, not only does the seal member seal between the mating faces of the parting line, but also at least a portion of the actual reinforcement member escapes inside the recessed step portion, such that the sealing abilities of the parting line are further enhanced, and such that molding defects of the molded body main body caused by the reinforcement member becoming trapped in the parting line can be more reliably prevented. 
         [0031]    The manufacturing method of a molded foam body of a sixth aspect is for manufacturing a molded foam body with reinforcement member, using the mold of the present invention. As previously described, the manufacturing method of the molded foam body of the present invention accordingly enables manufacture of the molded foam body disposed with the reinforcement member up to the position on the outer face of the molded body main body corresponding to the parting line of the cavity inner face of the mold, without causing molding defects to occur on the molded body main body. 
         [0032]    In the manufacturing method of a molded foam body of the present invention, as in the seventh aspect, the reinforcement member is preferably disposed such that the spacing between the outer peripheral edge of the reinforcement member and the parting line is 5 mm or less. Disposing the reinforcement member in this way enables manufacture of the molded foam body disposed with the reinforcement member substantially up to the position on the outer face of the molded body main body corresponding to the parting line of the cavity inner face of the mold, while more reliably not inducing the occurrence of molding defects on the molded body main body. 
         [0033]    In the molded foam body of the eighth aspect manufactured by the manufacturing method of a molded foam body of the present invention, occurrence of molding defects caused by the reinforcement member becoming trapped in the parting line of the molded body main body is prevented, and the reinforcement member is disposed up to the position on the outer face of the molded body main body corresponding to the parting line of the cavity inner face of the mold. 
         [0034]    As in the ninth aspect, the present invention is suitable for application to a seat pad. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0035]      FIG. 1  is a cross-section view of a mold according to a first exemplary embodiment. 
           [0036]      FIG. 2  is an enlarged cross-section view of portion II in  FIG. 1 . 
           [0037]      FIG. 3  is a plan view of a lower mold of the mold in  FIG. 1 . 
           [0038]      FIG. 4   a  is a back face view and  FIG. 4   b  is a cross-section view of a seat pad as a molded foam body manufactured using the mold in  FIG. 1 . 
           [0039]      FIGS. 5   a ,  5   b  are enlarged cross-section views of the same portion as in  FIG. 2  in a case in which a reinforcement member has entered a parting line of the mold in  FIG. 1 . 
           [0040]      FIG. 6   a  is a back face view and  FIG. 6   b  is a plan view of a lower mold illustrated in a second exemplary embodiment. 
           [0041]      FIGS. 7   a ,  7   b  are enlarged cross-section views of the same portion as in  FIG. 2  of a mold according to a third exemplary embodiment. 
           [0042]      FIG. 8  is a plan view of a lower mold of the mold in  FIGS. 7   a ,  7   b.    
           [0043]      FIG. 9  is a rear face view of a seat pad and a plan view of a lower mold illustrating a fourth exemplary embodiment. 
           [0044]      FIG. 10  is a cross-section view of a seat pad according to a conventional example. 
           [0045]      FIG. 11  is a cross-section view of a seat pad manufacturing mold according to a conventional example. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0046]    Explanation follows regarding exemplary embodiments, with reference to the drawings. Note that, although the following exemplary embodiments illustrate examples of application of the present invention to a mold for manufacturing a seat pad, and to a manufacturing method of a seat pad using the mold, the present invention is also applicable to a mold for manufacturing a molded foam body other than a seat pad, and to a manufacturing method for a molded foam body using the mold. 
       First Exemplary Embodiment 
       [0047]      FIG. 1  is a cross-section view of a mold according to a first exemplary embodiment.  FIG. 2  is an enlarged cross-section view of section II in  FIG. 1 .  FIG. 3  is a plan view of a lower mold of the mold.  FIG. 4   a  is a back face view of a seat pad as a molded foam body manufactured using the mold, and  FIG. 4   b  is a cross-section view taken along line IVB-IVB in  FIG. 4   a .  FIG. 5   a  and  FIG. 5   b  are enlarged cross-section views of the same portion as illustrated in  FIG. 2 , in a case in which a reinforcement member has entered a parting line of the mold.  FIG. 5   a  illustrates a state before mold fastening, and  FIG. 5   b  illustrates a state after mold fastening. 
         [0048]    In the present exemplary embodiment, a mold  1  serves to manufacture a seat pad  20  configuring a vehicle seat. Note that, although in the exemplary embodiment the seat pad  20  is a cushion pad configuring a seat section of a vehicle seat, the present invention is also applicable to a back pad configuring a backrest section of a vehicle seat.  FIG. 1  illustrates a vertical cross-section along the left-right direction of the seat pad (cushion pad)  20  during use. 
         [0049]    The seat pad  20  includes a seat pad main body  21  as a molded body main body comprising a foamable synthetic resin, such as polyurethane foam, and a reinforcement member  22  that is disposed across a back face of the seat pad main body  21  (the lower face of the seat pad main body  21  during use, since the seat pad  20  is a cushion pad in the exemplary embodiment) and integrated with the seat pad main body  21 . 
         [0050]    The reinforcement member  22  is disposed up to substantially the terminal end of the outer peripheral side of the back face of the seat pad main body  21 . In the exemplary embodiment, as illustrated in  FIGS. 4   a ,  4   b , the reinforcement member  22  is configured in a shape covering substantially the entire back face of the seat pad main body  21 , and the outer peripheral edge of the reinforcement member  22  is disposed so as to be aligned with the terminal end of the outer peripheral side of the back face of the seat pad main body  21  around the entire periphery. In the exemplary embodiment, a parting line P is present on the inner face of a cavity  4  of the mold  1 , described below, at a position corresponding to the terminal end of the outer peripheral side of the back face of the seat pad main body  21 . In the exemplary embodiment, the reinforcement member  22  is formed from an air permeable material. A non-woven fabric or the like is suitably applied as the air permeable material. 
         [0051]    Note that the shape, disposition, configuration material, and the like of the reinforcement member  22  are not limited thereto. For example, the reinforcement member  22  may be configured in a shape so as to cover a portion of the back face of the seat pad main body  21 , and a portion of the outer peripheral edge of the reinforcement member  22  may be disposed so as to be aligned with an portion of the outer peripheral side terminal end of the back face of the seat pad main body  21 . The reinforcement member  22  may be disposed at a region of the outer face of the seat pad main body  21  other than the back face of the seat pad main body  21 . The reinforcement member  22  may be disposed straddled across two or more faces out of the back face, side peripheral faces, and a seating face of the seat pad main body  21 . The reinforcement member  22  may be configured of a material other than a non-woven fabric. An air permeable member may be disposed to the reinforcement member  22  at a region overlapping with exhaust holes  5  of the mold  1 , described later. 
         [0052]    In the present invention, “the reinforcement member  22  is disposed up to substantially the terminal end (=the position on the seat pad main body  21  outer face corresponding to the parting line P of the inner face of the cavity  4  of the mold  1 , described later) of the outer peripheral side of the back face of the seat pad main body  21 ” indicates that, within a pre-set acceptable range of attachment error, the outer peripheral edge of the reinforcement member  22  may be positioned further to the center side of the back face than the outer peripheral side terminal end of the back face of the seat pad main body  21 , or may protrude out from the outer peripheral side terminal end of the back face toward the sides of the seat pad main body  21 . 
         [0053]    In the exemplary embodiment, as illustrated in  FIG. 1 , the mold  1  includes an upper mold  2  and a lower mold  3 , and exhaust holes  5  for discharging gas inside the cavity  4  surrounded by the upper mold  2  and the lower mold  3 , to outside the cavity  4 . Note that the mold  1  may also include a mold core (not illustrated in the drawings). In the exemplary embodiment, the upper mold  2  and the lower mold  3  are both equivalent to the molding molds of the first aspect. The upper mold  2  and the lower mold  3  mate together at respective peripheral edge portions. The symbol P indicates the parting line formed by joining together mating faces  2   a,    3   a  ( FIGS. 2 ,  3 ,  5   a ,  5   b ) of the peripheral edge portions of the upper mold  2  and the lower mold  3 . 
         [0054]    In the exemplary embodiment, the exhaust holes  5  are provided further to the center side of a cavity inner face  2   b  of the upper mold  2  than the parting line P. The exhaust holes  5  are disposed at portions of the cavity inner face  2   b  of the upper mold  2  where it is difficult to remove gas from the parting line P alone during foam molding, such as a portion at a higher position than the parting line P, or a portion where a location lower than the parting line P exists between the portion and the parting line P.  FIG. 1  illustrates two exhaust holes  5  disposed at a spacing in the seat pad left-right direction; however the quantity and placement of the exhaust holes  5  are not limited thereto. Note that the exhaust holes  5  may also be disposed to the lower mold  3 , or the like, if required. 
         [0055]    The seat pad  20  (the seat pad main body  21 ) is molded in the cavity  4  of the mold  1  with the seating face facing downward. Namely, the seating face and side peripheral faces of the seat pad  20  are molded by a cavity inner face  3   b  of the lower mold  3 , and the back face of the seat pad  20  is molded by the cavity inner face  2   b  of the upper mold  2 . The parting line P is positioned at a boundary portion of the back face and the side peripheral faces of the seat pad  20 , namely, at the outer peripheral side terminal end of the back face of the seat pad  20 . Note that placement of the parting line P is not limited thereto, and may be disposed at a position corresponding to a location other than the outer peripheral side terminal end of the back face of the seat pad main body  21 . Prior to the foam molding process of the seat pad  20 , the reinforcement member  22  is disposed across the cavity inner face  2   b  of the upper mold  2 , and the reinforcement member  22  is fixed to the upper mold  2  by a fixing (not illustrated in the drawings) such as pins or magnets. The outer peripheral edge of the reinforcement member  22  is disposed so as to be substantially aligned with the parting line P around the entire periphery when this placement is performed 
         [0056]    In the present invention, “the outer peripheral edge of the reinforcement member  22  is disposed so as to be substantially aligned with the parting line P around the entire periphery” indicates that, when attaching the reinforcement member  22  to the cavity inner face  2   b  of the upper mold  2 , within the pre-set acceptable range of attachment error, the outer peripheral edge of the reinforcement member  22  may be positioned further to the center side of the cavity inner face  2   b  than a boundary portion Bd 1  between the cavity inner face  2   b  and the mating face  2   a  of the upper mold  2 , or may protrude out from the boundary portion Bd 1  to the mating face  2   a  side (or, with the mold  1  in a fastened state, the peripheral edge portion of the reinforcement member  22  may cross the parting line P and overlap with the cavity inner face  3   b  of the lower mold  3 ). 
         [0057]    As illustrated in  FIG. 2  and  FIG. 5   b , when the mold  1  has been fastened, a boundary portion Bd 2  between the mating face  3   a  and the cavity inner face  3   b  of the lower mold  3 , overlaps on the extension direction of the mating faces  2   a,    3   a  with the boundary portion Bd 1  between the mating face  2   a  and the cavity inner face  2   b  of the upper mold  2 . Note that the respective boundary portions Bd 1 , Bd 2  may be offset in the extension direction of the mating faces  2   a,    3   a  when the mold  1  is in a fastened state. 
         [0058]    A seal member  7  is provided to the mold  1  in order to seal between the mating faces  2   a,    3   a  of the upper mold  2  and the lower mold  3 . The seal member  7  is configured by an elastic material such as rubber. Silicon rubber, fluorine rubber, nitrile rubber, or the like is suitable as the seal member  7 ; however configuration is not limited thereto. 
         [0059]    In the exemplary embodiment, a seal member attachment groove  2   c  is provided to the mating face  2   a  of the upper mold  2 , and a base end side (the upper end side in  FIGS. 2 ,  5   a ,  5   b ) of the seal member  7  is fixed to the upper mold  2  by fitting into the seal member attachment groove  2   c.  In the exemplary embodiment, the seal member  7  is provided around the entire periphery of the mating face  2   a  of the upper mold  2 . As illustrated in  FIG. 5   a , when the upper mold  2  and the lower mold  3  are in an opened state, a leading end side (the lower end side in  FIG. 2 , and  FIGS. 5   a ,  5   b ) of the seal member  7  is in a state protruding from the mating face  2   a  of the upper mold  2  toward the lower mold  3  side. During mold fastening, the leading end side of the seal member  7  is pressed against the mating face  3   a  of the lower mold  3 , and elastic close contact of the seal member  7  seals between the mating face  2   a  (the inner face of the seal member attachment groove  2   c ) of the upper mold  2  and the mating face  3   a  of the lower mold  3 . 
         [0060]    As illustrated in  FIG. 5   b , the seal member  7  is configured so as to be capable of sufficiently sealing between the mating faces  2   a,    3   a,  even suppose the reinforcement member  22  enters the parting line P during mold fastening and becomes trapped between the mating faces  2   a,    3   a  more to the cavity  4  side than the seal member  7 . Namely, a region of the mold  1  between the mating faces  2   a,    3   a  from the cavity  4  inner face (boundary portions Bd 1 , Bd 2 ) to the seal member  7  forms an acceptable region for trapping the reinforcement member, that allows the reinforcement member  22  to become trapped between the mating faces  2   a,    3   a  during mold fastening, and is capable of sufficiently sealing between the mating faces  2   a,    3   a , even with the reinforcement member  22  trapped in between. 
         [0061]    A distance W 1  ( FIG. 2 ) from the inner face of the cavity  4  to the seal member  7  (namely, the width of the acceptable region for trapping the reinforcement member) is suitably set corresponding to the acceptable range of attachment error of the reinforcement member  22 , pre-set for the seat pad  20  manufactured using the mold  1 . For example, in order to configure the seat pad  20  as a common, ordinary vehicle seat, the acceptable range of attachment error of the reinforcement member  22  is approximately from 0 mm to 5 mm. In such cases, the distance W 1  from the inner face of the cavity  4  to the seal member  7  is preferably from 1 mm to 10 mm, and particularly preferably from 5 mm to 10 mm. 
         [0062]    An projection height T of the seal member  7  from the mating face  2   a  with the mold in an opened state ( FIG. 5   a ; hereafter simply referred to as projection height T) is suitably set according to the thickness of the reinforcement member  22  used in the seat pad  20 . Note that, since it is generally difficult to unambiguously derive the thickness of the reinforcement member  22  by actual measurement when a fabric material, such as a non-woven fabric, is used as the configuration material for the reinforcement member  22 , the projection height T is preferably set according to the basis weight of the fabric material. Specifically, in cases in which the reinforcement member  22  is configured by a non-woven fabric, for example, when the basis weight of the non-woven fabric is from 0.05 kg/m 2  to 0.1 kg/m 2 , the projection height T is preferably from 0.2 mm to 1.5 mm and particularly preferably from 0.5 mm to 0.8 mm, and when the basis weight of the non-woven fabric is from 0.1 kg/m 2  to 0.2 kg/m 2 , the projection height T is preferably from 0.5 mm to 1.5 mm and particularly preferably from 0.8 mm to 1.2 mm. 
         [0063]    Note that, although in the exemplary embodiment the seal member  7  is provided to the mating face  2   a  of the upper mold  2 , the seal member  7  may be provided to the mating face  3   a  of the lower mold  3 , or may be provided to both the mating faces  2   a,    3   a  of the upper mold  2  and the lower mold  3 , respectively. 
         [0064]    Explanation follows regarding a procedure for manufacturing the seat pad  20  using the mold  1 . 
         [0065]    First, the upper mold  2  and the lower mold  3  are opened, the reinforcement member  22  is disposed across the cavity inner face  2   b  of the upper mold  2 , and the reinforcement member  22  is fixed to the upper mold  2  by the fixing (a reinforcement placement process). In the exemplary embodiment, the reinforcement member  22  is disposed so as to cover the entire cavity inner face  2   b  of the upper mold  2 , and the outer peripheral edge of the reinforcement member  22  is aligned around the entire periphery with the parting line P (the boundary portion Bd 1  between the cavity inner face  2   b  and the mating face  2   a  of the upper mold  2 ). 
         [0066]    Next, foamable synthetic resin raw material is poured into the lower mold  3 , the lower mold  3  and the upper mold  2  are fastened, and the raw material is foamed (a foam molding process). A foamed synthetic resin formed from the foamable raw material fills inside the cavity  4 . When this placement is performed, gas inside the cavity  4  permeates through the reinforcement member  22  formed from an air permeable material, and is discharged from the cavity  4  through the exhaust holes  5 . The seat pad main body  21  is formed, and the seat pad main body  21  and the reinforcement member  22  are integrated together by the foamable synthetic resin filling inside the cavity  4 . After the foamed synthetic resin has cured, the mold is opened and removed. The seat pad  20  is then completed by surface finishing treatment of the seat pad  20 , if required. 
         [0067]    In the mold  1 , the seal member  7  seals between the mating faces  2   a,    3   a  during mold fastening. Suppose the reinforcement member  22  becomes trapped between the mating faces  2   a,    3   a  more to the cavity  4  side than the seal member  7  during mold fastening, configuration is such that the seal member  7  is able to seal between the mating faces  2   a,    3   a . This enables molding defects of the seat pad main body  21  caused by the reinforcement member becoming trapped in the parting line P to be reliably prevented. This accordingly enables manufacture of the seat pad  20  disposed with the reinforcement member  22  up to a position on the seat pad main body  21  outer face corresponding to the parting line P of the cavity  4  inner face of the mold  1 , without occurrence of molding defects of the seat pad main body  21 . 
         [0068]    In the exemplary embodiment, the seal member  7  is provided around the entire periphery of the parting line P, thereby enabling sufficient sealing between the mating faces  2   a ,  3   a  by the seal member  7  around the entire periphery of the parting line P during mold fastening. 
         [0069]    As previously described, since the acceptable range of attachment error of the reinforcement member  22  is approximately from 0 mm to 5 mm for a seat pad  20  used in an ordinary vehicle seat, by setting the distance W 1  from the inner face of the cavity  4  to the seal member  7  from 1 mm to 10 mm, and preferably from 5 mm to 10 mm, as in the exemplary embodiment, molding defects of the seat pad main body  21  caused by the reinforcement member  22  becoming trapped in the parting line P can be more reliably prevented, even when there is attachment error of the reinforcement member  22  within the acceptable range. 
         [0070]    In the exemplary embodiment, the reinforcement member  22  is configured from a non-woven fabric, and the projection height T of the seal member  7  from the mating face  2   a  with the mold is an opened state is suitably set according to the basis weight of the non-woven fabric. Namely, when the basis weight of the non-woven fabric is from 0.05 kg/m 2  to 0.1 kg/m 2 , the projection height T is preferably from 0.2 mm to 0.8 mm, and when the basis weight of the non-woven fabric is from 0.1 kg/m 2  to 0.2 kg/m 2 , the projection height T is preferably from 0.8 mm to 1.5 mm. With such a configuration, the seal member  7  is firmly pressed against the mating face  3   a  of the lower mold  3  even when the reinforcement member  22  enters between the mating faces  2   a,    3   a,  enabling sufficient sealing between the mating faces  2   a,    3   a  by the seal member  7 . 
       Second Exemplary Embodiment 
       [0071]      FIG. 6   a  is a back face view of a seat pad manufactured using a mold according to a second exemplary embodiment, and  FIG. 6   b  is a plan view of a lower mold of the mold. 
         [0072]    In the seat pad  20  of the first exemplary embodiment described above, the reinforcement member  22  is configured so as to cover substantially the entire back face of the seat pad main body  21 , and when the reinforcement member  22  has been disposed across the cavity inner face  2   a  of the upper mold  2 , the outer peripheral edge of the reinforcement member  22  is adjacent to the parting line P of the mold  1  around the entire periphery of the parting line P. As a result, in the first exemplary embodiment, the seal member  7  is separated from the inner face of the cavity  4  around the entire periphery of the parting line P by the distance W 1 , and the acceptable region for trapping the reinforcement member is formed therebetween. However, in the present invention, the reinforcement member  22  may also be configured so as to cover only a portion of the back face of a seat pad main body  21 . In such a case, the acceptable region for trapping the reinforcement member between the seal member  7  and the inner face of the cavity  4  may be formed only to portions of the parting line P adjacent to the outer peripheral edge of the reinforcement member  22 . 
         [0073]    For example, in a seat pad  20 A of the second exemplary embodiment, as illustrated in  FIG. 6   a , the shape of a reinforcement member  22  is configured so as to cover only a front-rear direction rear half side (hereafter simply referred to as the rear half side) of a back face of a seat pad main body  21  during use of the seat pad  20 A, and the reinforcement member  22  is disposed up to the outer peripheral edge of the rear half side of the back face of the seat pad main body  21 . As a result, when the reinforcement member  22  is disposed across a cavity inner face  2   a  of an upper mold  2  (not illustrated in  FIG. 6   b ), the outer peripheral edge of the reinforcement member  22  is only adjacent to substantially the half-peripheral portion of the parting line P corresponding to the outer peripheral edge of the back face rear half side of the seat pad main body  21 . Accordingly, in the exemplary embodiment, as illustrated in  FIG. 6   b , it is sufficient to separate the seal member  7  from the inner face of the cavity  4  by the distance W 1  to the parting line P only at substantially the half-peripheral portion rear half side, adjacent to the outer peripheral edge of the reinforcement member  22 , and to form the acceptable region for trapping the reinforcement member therebetween. 
         [0074]    It is preferable to make the distance from the cavity  4  to the seal member  7  as small as possible at the remaining portion of the parting line P that is not adjacent to the outer peripheral edge of the reinforcement member  22 . This thereby prevents unnecessary burring of the seat pad main body  21 , or the like, from occurring. 
         [0075]    Note that although, as illustrated in  FIG. 6   b , the seal member  7  is provided to the mating face  2   a  of the upper mold  2  in the present exemplary embodiment, the seal member  7  may be provided to the mating face  3   a  of the lower mold  3 , or provided to both the mating faces  2   a,    3   a  of the upper mold  2  and the lower mold  3 , respectively. 
         [0076]    Other configuration of the second exemplary embodiment is similar to the first exemplary embodiment. 
       Third Exemplary Embodiment 
       [0077]      FIGS. 7   a ,  7   b  are enlarged cross-section views of the vicinity of a parting line of a mold according to a third exemplary embodiment (a similar portion to that illustrated in  FIG. 2 ).  FIG. 7   a  illustrates a state before mold fastening, and  FIG. 7   b  illustrates a state after mold fastening. Note that  FIGS. 7   a ,  7   b  illustrate a case in which a reinforcement member has entered the parting line of the mold.  FIG. 8  is a plan view of a lower mold of the mold. 
         [0078]    In a mold  1 A of the exemplary embodiment, a recessed step portion  6  facing inside the cavity  4  is provided to the mating face  3   a  of the lower mold  3 , and a seal member  7  is provided at an opposite side from the cavity  4  than the recessed step portion  6 . The recessed step portion  6  is configured such that the reinforcement member  22  can escape inside the recessed step portion  6  in cases in which the reinforcement member  22  enters the parting line P (between the respective mating faces  2   a,    3   a ). Similarly to the first exemplary embodiment, in the present exemplary embodiment, the outer peripheral edge of the reinforcement member  22  is disposed so as to be as adjacent to the parting line P around the entire periphery of the parting line P. As a result, the recessed step portion  6  is also formed around the entire periphery of the mating face  3   a,  as illustrated in  FIG. 8 . 
         [0079]    As illustrated in  FIG. 7   b , when the mold  1 A has been fastened, a boundary portion Bd 2 ′ between a bottom face of the recessed step portion  6  and the cavity inner face  3   b  of the lower mold  3 , overlaps on the extension direction of the mating faces  2   a,    3   a  with the previously described boundary portion Bd 1  between the mating face  2   a  and the cavity inner face  2   b  of the upper mold  2 . Note that the respective boundary portions Bd 1 , Bd 2 ′ may be offset in the extension direction of the mating faces  2   a,    3   a  when the mold  1 A is in a fastened state. 
         [0080]    Similarly to the distance W 2  from the inner face of the cavity  4  to the seal member  7 , a width W 2  of the recessed step portion  6  from a boundary portion Bd 2 ′ in the mating faces  2   a ,  3   a  extension direction and the direction towards and away from the cavity  4  ( FIG. 7   a ; hereafter simply referred to as width W 1 ), is suitably set corresponding to the acceptable range of attachment error of the reinforcement member  22 , pre-set for a seat pad  20  manufactured using the mold  1 A. For example, in order to configure the seat pad  20  as a common ordinary vehicle seat, the acceptable range of attachment error of the reinforcement member  22  is approximately from 0 mm to 5 mm. In such cases, the width W 2  of the recessed step portion  6  is preferably from 1 mm to 10 mm, and particularly preferably from 3 mm to 5 mm. 
         [0081]    Similarly to the projection height T of the seal member  7 , a depth D from the mating face  3   a  to the bottom face of the recessed step portion  6  ( FIG. 7   a ; hereafter simply referred to as depth D), is suitably set according to the thickness of the reinforcement member  22  used for the seat pad  20 . It is preferable to set the depth D of the recessed step portion  6  according to the fabric basis weight in cases in which a fabric material, such as a non-woven fabric, is used as the configuration material of the reinforcement member  22 . Specifically, in cases in which the reinforcement member  22  is configured by a non-woven fabric, for example, when the basis weight of the non-woven fabric is from 0.05 kg/m 2  to 0.1 kg/m 2 , the depth D is preferably from 0.2 mm to 0.5 mm and particularly preferably from 0.3 mm to 0.4 mm, and when the basis weight of the non-woven fabric is from 0.1 kg/m 2  to 0.2 kg/m 2 , the depth D is preferably from 0.3 mm to 0.6 mm and particularly preferably from 0.4 mm to 0.5 mm. 
         [0082]    Note that the seal member  7  may be disposed with a spacing toward the cavity  4  outside from the recessed step portion  6 , or may be disposed adjacent to the recessed step portion  6 . The spacing between the seal member  7  and the recessed step portion  6  is preferably from 1 mm to 10 mm, and particularly preferably from 3 mm to 5 mm. 
         [0083]    Other configuration of the mold  1 A is similar to the mold  1  of the first exemplary embodiment, and in  FIGS. 7   a ,  7   b ,  8 , the same reference numerals as  FIGS. 1 to 5   b  indicate the same portions. Moreover, the method of manufacturing the seat pad  20  using the mold  1 A is similar to when the mold  1  is used. 
         [0084]    The mold  1 A also exhibits similar advantageous effects to the mold  1  of the first exemplary embodiment. 
         [0085]    A recessed step portion  6  facing inside the cavity  4  is provided to the mating face  3   a  of the lower mold  3  of the mold  1 A. The recessed step portion  6  is configured such that the reinforcement member  22  can escape inside the recessed step portion  6  in cases in which the reinforcement member  22  enters the parting line P between the respective mating faces  2   a,    3   a  during mold fastening. The seal member  7  is disposed at the opposite side from the cavity  4  than the recessed step portion  6 . As a result, in cases in which the reinforcement member  22  enters between the respective mating faces  2   a,    3   a  when the mold is fastened, not only does the seal member  7  seal between the respective mating faces  2   a,    3   a,  but also at least a portion of the actual reinforcement member  22  escapes inside the recessed step portion  6 , such that the sealing abilities of the parting line P are enhanced, and such that molding defects of the seat pad main body  21  caused by the reinforcement member  22  becoming trapped in the parting line P can be more reliably prevented. 
         [0086]    Note that, although the recessed step portion  6  is provided to the mating face  3   a  of lower mold  3  in the present exemplary embodiment, the recessed step portion  6  may be provided to the mating face  2   a  of the upper mold  2 , or provided to both the mating faces  2   a ,  3   a  of the upper mold  2  and the lower mold  3 , respectively. 
       Fourth Exemplary Embodiment 
       [0087]      FIG. 9  is a plan view of a lower mold of a mold according to a fourth exemplary embodiment. 
         [0088]    As in the second exemplary embodiment previously described, in cases in which a reinforcement member  22  is only adjacent to a portion of a parting line P, it is sufficient to only provide a recessed step portion  6  to the portion of the parting line P to which the reinforcement member  22  is adjacent. 
         [0089]    It is preferable not to provide the recessed step portion  6  to the remaining portion of the parting line P that is not adjacent to the outer peripheral edge of the reinforcement member  22 . This prevents unnecessary burring of the seat pad main body  21 , or the like, from occurring. 
         [0090]    Other configuration of the fourth exemplary embodiment is similar to that of the second and the third exemplary embodiment. 
         [0091]    Each of the exemplary embodiments described above is merely an example of the present invention, and the present invention may be configured differently to the configurations illustrated. 
         [0092]    For example, in each of the exemplary embodiments described above, an example is given of the present invention applied to a seat pad; however the present invention is also applicable to a molded foam body other than a seat pad. 
         [0093]    The present invention is not limited to the mating faces of an upper mold and a lower mold, and may be applied to all mating locations of a mold, such as between an upper mold and a mold core, or a lower mold and a mold core. 
         [0094]    The present invention is explained in detail herein using specific embodiments; however it is obvious to a person skilled in the art than various modifications are possible without departing from the spirit and scope of the invention. Note that the present application is based on Japanese Patent Application (Patent Application No. 2012-028461) filed on Feb. 13, 2012, the entirety of which is incorporated by reference herein.