JP2004090368A - Mold for molding foaming resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold for molding a foaming resin capable of reducing steam required for molding. <P>SOLUTION: The mold 1 for molding the foaming resin is provided with a first mold 2 and a second mold 3 both provided with a plurality of steam holes, and particles of the foaming resin are filled into a cavity 4 formed by mating these first and second molds 2 and 3. The particles of the foaming resin are brought into contact with steam through a plurality of the steam holes to prepare a molded article of the foaming resin. In addition, between a support 5 and a back plate 6 of the first and second molds 2 and 3, a protective material 7 consisting of a moisture-proof rigid material and a thermal insulating material 8 consisting of a compression-resistant thermal insulating material are laminated. <P>COPYRIGHT: (C)2004,JPO

Description

【００２２】
表１から、本発明に係る実施例の発泡樹脂成形型は、比較例１〜２の発泡樹脂成形型に比べて優れた断熱効果が得られ、使用蒸気量が削減できることが確認された。
【００２３】
（断熱材圧縮試験）
汎用のポリスチレン製発泡樹脂成形品の製造に使用している通常の発泡樹脂成形機において、サポートの本数は２０から３０本程度であり、またφ２５のサポートであれば、一本当たり２５５ｋｇ／ｃｍ^２〜１７０ｋｇ／ｃｍ^２程度の圧縮力を受けることになる。荷重を受けているのは、１サイクル１２０秒のうち、約８０秒程度であり、残る４０秒は開放状態となる。本発明の発泡樹脂成形型のように、バックプレートとサポートの間に断熱材と保護材を積層して設けた構造では、断熱材に耐圧縮性が無いと、サポートに当たる部分の断熱材が容易に変形してしまい、サポートによる第１，第２の成形型の位置調整ができなくなり、成形型が歪んで目的の形状や寸法の成形品が得られなくなる。したがって、本発明では耐圧縮性を有する断熱材を用いる必要がある。
本発明において断熱材として用いるアスベストと、比較のために従来技術において断熱材として用いられるゴム板との圧縮応力と歪み量の測定を行った。測定にはオリエンテック社製テンシロンＵＣＴ−５Ｔを用い、ロードセルはオリエンテック社製ＴＹＰＥ　ＵＦ−５　Ｃａｐ．５ｔｆ　ＳＥＲ．ＮＯ．０４９５３９を用いた。試験環境は温度２５℃、湿度５０ＲＨ％である。
【００２４】
▲１▼アスベスト製のジョイントシート、板厚１ｍｍ（日本バルカー社製の商品Ｎｏ．＃１５００）（表２中「アスベストシート」と記す）：板厚１２ｍｍ、２０ｃｍ角のアルミニウム板（バックプレートに使用するものと同じ材質Ａ５０５２）に上記アスベストシートを載せ、サポート材に使用する直径２５ｍｍ、長さ３７ｍｍのアルミニウム製丸棒（材質Ａ５０５２）をロードセルとシートの間に挟み、圧縮試験を行った。
【００２５】
▲２▼ゴム板、板厚４ｍｍ：
上記▲１▼と同じアルミニウム板に、成形型のバックプレートに施すゴムライニング（ゴムの板厚４ｍｍ）と同じ施工を施したものを、上記▲１▼と同じ要領で圧縮試験を行った。
上記▲１▼、▲２▼について、応力２５５ｋｇｆ／ｃｍ^２における断熱材の歪み量（ｍｍ）を測定し、その結果を次の表２に記す。また、▲１▼、▲２▼の断熱材の熱伝導率λ（Ｗ／ｍ・ｋ）も表２に記す。
【００２６】
【表２】

【００２７】
表２の結果より、アスベストシートは従来のゴムライニングと比べて圧縮時の歪みが小さく、本発明の断熱材として好適であることが判る。一方、ゴム板は歪み量が大きく、本発明のようにバックプレートとサポートとの間に断熱材と保護材を積層して設ける構造では、圧縮付加時に変形量が大きく、成形品の変形や寸法変化を生じる可能性があることから、本発明に用いる断熱材として不適であった。
【００２８】
【発明の効果】
本発明の発泡樹脂成形型は、サポートとバックプレートとの間に保護材と断熱材とを積層して配置したものなので、バックプレートを断熱でき、さらにサポートが直接バックプレートに当たらないため、サポートからバックプレートへの伝熱が遮断され、蒸気室の断熱性が高くなり、成形時の使用蒸気量を削減できる。また、保護材の表面は平滑であり、蒸気ドレンおよび冷却水が該表面から落ち易く、真空放冷時に付着水の蒸発潜熱が小さくなり無駄な冷却が抑えられる。
さらに、保護材がサポート当接時に断熱材を破れ、傷付きなどから保護するので、断熱材の長寿命化を図ることができる。
また、バックプレートの表面に断熱材と保護材を積層し、該保護材に直接サポートを当てることができるため、これらを一度取り付ければ、第１、第２の成形型を交換する際に、この断熱材と保護材を取り付けたバックプレートは共通使用でき、無駄な交換作業が不要となる。また従来技術において用いているような遮蔽板は不要となり、第１、第２の成形型交換時に遮蔽板をつけ替える余分な操作が不要となる。
さらに、サポートとバックプレートとの間に保護材と断熱材とを挟み込んで取り付ける場合、保護材と断熱材との周囲のみ密着固定するため、これらの中央部分では、バックプレートと断熱材の間および断熱材と保護材との間に若干の空気層が形成されるため、断熱材のみの断熱効果を上回る断熱効果が得られる。
【図面の簡単な説明】
【図１】本発明の発泡樹脂成形型の一実施形態を示す要部断面図である。
【図２】実施例において比較のために用いた比較例１の発泡樹脂成形型の構造を示す要部断面図である。
【図３】実施例において比較のために用いた比較例２の発泡樹脂成形型の構造を示す要部断面図である。
【符号の説明】
１　　発泡樹脂成形型
２　　第１の成形型
３　　第２の成形型
４　　キャビティ
５　　サポート
６　　バックプレート
７　　保護材
８　　断熱材
９　　蒸気室
１２，１３　　フレーム
１４　　固定用ボルト[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a foamed resin mold for producing foamed resin molded articles by bringing foamable resin particles into contact with steam in a pair of molds, and more particularly to an improvement in a foamed resin mold capable of reducing the amount of steam used.
[0002]
[Prior art]
In the molding step of the in-mold molding method using the expandable resin particles (also referred to as expanded beads, beads, or the like), a molding process is performed by combining a first molding die and a second molding die together with a space portion ( Cavity) is filled with foamable resin particles as a raw material, and steam is supplied to the foamed particles through a steam chamber (a space surrounded by a frame, a back plate, and a mold) and steam holes provided in the mold to be heated. After that, cooling water is supplied to the steam chamber to cool the mold, and then the steam chamber is depressurized to evaporate steam drain water and cooling water adhering to the mold, frame, and back plate, and vaporize the steam. The method further comprises the steps of further cooling the mold with heat and then removing the molded product from the mold. 80-90% of the steam used during the molding is consumed for heating the mold, frame, back plate and other parts. Therefore, techniques for reducing the steam consumed for heating the mold and the like have been conventionally studied, and some proposals have been made.
The mold used for in-mold molding of the expandable resin particles is roughly divided into two structurally. One is a mold for forming the shape of a product, and the other is a frame and a back plate that fix the mold and constitute a steam chamber. Heating load = Specific heat of material × Weight of material × Maximum and minimum temperature difference. Therefore, the method for reducing the heating steam is as follows: (1) Reduce the weight of the mold, frame, and back plate to reduce the heating load (2) Insulate the frame and back plate on the steam chamber side to minimize the maximum and minimum temperature difference between them. (3) It is conceivable to raise the minimum temperature of the mold, that is, the temperature at which the product is taken out of the mold as much as possible.
[0003]
As a conventional technique for reducing the amount of steam used in a foamed resin mold, for example, there is the following proposal.
(1) Japanese Utility Model Publication No. Sho 61-7073 discloses a foam having a structure in which a shielding plate made of a stainless steel thin plate is provided at an interval in front of a back plate to separate a space (steam chamber) between the back plate and a molding die. A steam chamber in a molding machine is disclosed. The publication discloses that the back plate is not cooled by the cooling water due to the structure, and the amount of steam during heating can be saved.
(2) JP-A-57-68322 discloses that a heat insulating shielding plate is fixed in close contact with a mold member on the upper side, a gap is provided between the mold member on the lower side, and water that has entered the gap is lowered. There is disclosed a foaming mold that is provided so as to flow out. An FRP plate, a rubber plate, a fluororesin plate, or the like is used as the heat insulation shielding plate.
(3) JP-A-58-15024 discloses a foamed resin molding machine in which a shielding plate is provided in a steam chamber with a slight gap left between the inner surface of a back plate and the steam chamber.
(4) JP-A-5-212810 discloses an in-mold foam molding in which a heat-insulating connecting plate is inserted into a surface where a molding die and a frame are attached to prevent heat transfer from the frame and promote cooling and heating of the molding die. A mold insulation structure for a machine is disclosed. Paragraph No. 0033 of the publication discloses that it is a known technique to heat-insulate the inside of a mold with a rubber lining or the like.
{Circle around (5)} Japanese Patent Application Laid-Open No. 8-142091 discloses a foaming mold for synthetic resin in which a scattering prevention plate is provided in front of a back plate at an interval in the same manner as in the above <1>.
[0004]
[Problems to be solved by the invention]
However, the above-described prior art has the following problems.
In the prior art (1), since there is a space between the back plate and the shielding plate, the back plate is not insulated. In addition, it is necessary to apply a support from the mold to the back plate in order to prevent the mold from expanding toward the back plate because the foamable resin particles of the raw material further expand on the back plate during heating. That is, the shielding plate placed so as to shield the space between the back plate and the mold always needs a through hole for the support to pass through. However, the shapes to be molded vary widely, and the positions and quantities of the supports vary widely. As a result, a shielding plate is required for each molding die, leading to an increase in cost. In addition, the man-hour for the work of changing the mold is increased. The frame and the core-side back plate are commonly used.
The prior art (2) is the same as (1) in that a gap is provided on the lower side of the frame. The upper side is closely attached to the back plate, but since the heat insulating shielding plate is a soft material such as an FRP plate, a rubber plate or a fluororesin plate, the above support cannot be directly applied to these, and an opening process is required. The points are the same as (1).
In the conventional technology of (3), as in (1), there is a space between the back plate and the shielding plate, so that a sufficient heat insulating effect cannot be obtained, and a shielding plate is required for each molding die, thereby increasing costs. In addition, there is a problem that the number of work steps increases.
The prior art of (4) is a measure for preventing the heat of the frame or the like from being transferred to the mold, and the amount of steam reduced by this is small. Also, (4) describes that it is a known technique to heat-insulate the inside of the mold with rubber lining or the like. However, as described in Comparative Example 2 in Examples described later, rubber lining is applied to the inner surface of the mold. Does not provide a sufficient effect of reducing the amount of steam.
In the conventional technology of (5), as in (1), there is a space between the back plate and the shielding plate, so that a sufficient heat insulating effect cannot be obtained, and a shielding plate is required for each molding die, thereby increasing costs. In addition, there is a problem that the number of work steps increases.
Further, as a problem common to the above-described prior arts (1) to (5), the molding die is fixed to the back plate via a plurality of supports serving as support members, and heat is transferred to the back plate through the supports. As a result, there is a problem that the heat insulation effect of each of the shielding plates and the like is reduced.
[0005]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a foamed resin mold capable of reducing steam required for molding.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention includes a first mold and a second mold provided with a plurality of steam holes, and is formed by combining the first and second molds. Filling the cavity with expandable resin particles, contacting the expandable resin particles with steam through the plurality of steam holes, and forming a foamed resin molded product in a foamed resin mold, a support for the mold and a back plate. The present invention provides a foamed resin mold characterized by laminating a protective material made of a moisture-resistant hard material and a heat-insulating material made of a compression-resistant heat-insulating material.
In the foamed resin molding die of the present invention, the heat insulating material is represented by t ′ / T, where t ′ (mm) is the amount of compressive strain of the heat insulating material, and T (mm) is the thickness of the bottom portion of the foamed resin molded product. Those satisfying the relationship of ≦ 0.05 are preferred.
Further, it is preferable that the protective material and the heat insulating material are fixed in a state in which the periphery thereof is tightly fixed to the back plate, and is attached with the support abutting portion sandwiched between the support and the back plate.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an embodiment of a foamed resin mold according to the present invention. In the figure, reference numeral 1 denotes a foamed resin mold.
This foamed resin molding die 1 includes a first molding die 2 and a second molding die 3 provided with a plurality of steam holes (not shown), and these first and second molding dies 2 and 3 are provided. The cavity 4 formed together is filled with foamable resin particles, and steam is brought into contact with the foamable resin particles through the plurality of steam holes to produce a foamed resin molded product. A protective member 7 made of a moisture-resistant hard material and a heat insulating material 8 are laminated between the support 5 of the second molds 2 and 3 and the back plate 6.
[0008]
The first molding die 2 and the second molding die 3 are joined by fastening fixing bolts 14 to the respective ends of the frames 12 and 13. The other ends of the frames 12 and 13 are joined to the ends of the back plate 6 that covers the outer surfaces of the first mold 2 and the second mold 3 by fastening fixing bolts 14. ing. A plurality of supports 5 are provided between the first mold 2 and the back plate 6 outside the first mold 2 and between the second mold 3 and the back plate 6 outside the first mold 2. And the second mold 3.
[0009]
The second molding die 3 is connected to a supply path of a feeder 10 that penetrates the back plate 6 and the second molding die 3 and supplies the expandable resin particles into the cavity 4. An eject pin 11 is joined to the second mold 3.
The space between the first mold 2 and the back plate 6 and the space between the second mold 3 and the back plate 6 are steam chambers 9 to which steam is supplied at the time of molding.
[0010]
Among the protective material 7 and the heat insulating material 8 laminated between the back plate 6 and the support 5, the protective material 7 is a hard material having water resistance and no water absorption, preferably a plate material having water repellency. For example, a heat-resistant hard plastic film such as a metal plate, a ceramic plate, and a polyimide film is preferably used, and a metal plate such as a stainless steel plate, an aluminum plate or an aluminum alloy, a copper plate or a copper alloy plate is particularly preferable. The thickness of the protective material 7 to be used is set to such an extent that a strength that does not cause deformation at a portion in contact with the support 5 is obtained.
[0011]
The heat insulating material 8 is made of a compression-resistant heat insulating material. When the amount of compressive strain of the heat insulating material is t ′ (mm) and the thickness of the bottom portion of the foamed resin molded product is T (mm), t ′ / T Those satisfying the relationship of ≦ 0.05 are preferred, and specific examples include asbestos sheets, glass fiber reinforced plastics, and rock wool. A commercially available product suitable for the heat insulating material 8 is exemplified by Product No. # 1500, a joint sheet made of asbestos (plate thickness 1 mm) and the like. Further, t ′ is the amount of distortion (mm) of the heat insulating material at a stress of 255 kgf / cm 2. When t '/ T exceeds 0.05, it is difficult to adjust the positions of the first and second molding dies 2 and 3 by the support 5, and the molding dies are distorted and the molded products having the desired shape and dimensions are obtained. May not be obtained. More preferably, t ′ / T ≦ 0.025.
[0012]
The protective member 7 and the heat insulating member 8 are desirably attached so as to be sandwiched between the frames 12, 13 and the back plate 6 using fixing bolts 14 originally used for joining the frames. By attaching the protection member 7 and the heat insulating material 8 using the existing fixing bolts 14 in this manner, a special mounting structure and a fixing member are not required, and the mounting member can be easily attached to the existing foamed resin molding die.
[0013]
In the foamed resin molding die 1 of the present embodiment, a cavity 4 formed by combining the first molding die 2 and the second molding die 3 is filled with foamable resin particles as a raw material, and steam is supplied into the steam chamber 9. And heating the foamable resin particles through steam holes provided in the first and second molding dies 2 and 3, and then supplying cooling water to the steam chamber 9 to supply the first and second molding dies 2 to each other. , 3 are cooled, and then the steam chamber 9 is depressurized to evaporate steam drain water and cooling water adhering to the first and second molds 2, 3, the frames 12, 13 and the back plate 6. Then, the first and second molding dies 2 and 3 are further cooled by the heat of vaporization, and thereafter, the molded product can be manufactured through the respective steps of taking out the molded product.
[0014]
Expandable resin particles are obtained by pre-expanding synthetic resin particles containing a foaming agent.The synthetic resin constituting the synthetic resin particles has been conventionally used for the production of foamed resin molded products. It can be appropriately selected from among the resin materials that are used, is not particularly limited, for example, polystyrene resins such as polystyrene, high impact polystyrene, styrene-maleic anhydride copolymer, styrene-acrylonitrile copolymer, Examples thereof include polyolefin resins such as polyethylene, polypropylene, and ethylene-vinyl acetate copolymer, and polyester resins such as polyethylene terephthalate. Polystyrene resins are preferable from the viewpoint of strength and moldability.
[0015]
Further, as the foaming agent, a gaseous or liquid organic compound having a boiling point equal to or lower than the softening point of the synthetic resin at normal pressure is suitable, for example, propane, butane, pentane, cyclopentane, cyclopentadiene, and hexane. For example, hydrocarbons such as petroleum ether, low-boiling ether compounds such as dimethyl ether, diethyl ether, dipropyl ether and methyl ethyl ether, and inorganic gases such as carbon dioxide and nitrogen are used. These foaming agents may be used alone or in combination of two or more.
The content of the foaming agent is 1 to 20% by weight, preferably 2 to 10% by weight, based on the weight of the synthetic resin particles. When the content of the foaming agent is less than the above range, the foaming ratio of the foamed molded product is insufficient and a lightweight foam cannot be obtained. On the other hand, if the content of the foaming agent exceeds the above range, further increase in the foaming ratio cannot be substantially expected, and foaming becomes unstable, which is not preferable.
[0016]
In the foamed resin mold of the present embodiment, the protective material 7 and the heat insulating material 8 are stacked and arranged between the support 5 and the back plate 6, so that the back plate 6 can be insulated and the support 5 can be directly backed. Since it does not hit the plate 6, the heat transfer from the support 5 to the back plate 6 is cut off, the heat insulation of the steam chamber 9 is increased, and the amount of steam used during molding can be reduced.
Further, the surface of the protective material 7 is smooth, so that the steam drain and the cooling water easily fall from the surface, and the latent heat of evaporation of the adhering water during cooling in a vacuum is reduced, so that unnecessary cooling is suppressed. Further, since the protective material 7 protects the heat insulating material 8 from being broken when the support 5 comes into contact with the support 5, the life of the heat insulating material 8 can be extended.
In addition, since the heat insulating material 8 and the protective material 7 can be laminated on the surface of the back plate 6 and the support can be directly applied to the protective material 7, once they are attached, the first and second molding dies 2, 3 When exchanging, the back plate 6 to which the heat insulating material 8 and the protective material 7 are attached can be used in common, and unnecessary exchange work is not required. Further, the shielding plate used in the prior art is not required, and an extra operation of replacing the shielding plate when replacing the first and second molds 2 and 3 is not required.
Furthermore, when the protective member 7 and the heat insulating material 8 are sandwiched between the support 5 and the back plate 6 and attached, only the periphery of the protective material 7 and the heat insulating material 8 are tightly fixed. Since a small air layer is formed between the heat insulating material 6 and the heat insulating material 8 and between the heat insulating material 8 and the protective material 7, a heat insulating effect exceeding the heat insulating effect of only the heat insulating material 8 can be obtained.
Hereinafter, the effects of the present invention will be demonstrated by examples.
[0017]
【Example】
(Example)
As an embodiment of the foamed resin mold according to the present invention, as shown in FIG. 1, a protective plate 7 made of a stainless steel plate having a thickness of 1 mm is provided between each of the frames 12 and 13 and the back plates 6 and 6. A laminate of the heat insulating material 8 composed of a 1 mm-thick asbestos joint plate (product No. # 1500 manufactured by Nippon Valqua Co., Ltd.) is sandwiched, and the frames 12, 13 and the back plates 6, 6 are fixed with fixing bolts 14. The foamed resin mold 1 attached by fixing was used. The support 5 was attached directly to the protective material.
[0018]
(Comparative Example 1)
As shown in FIG. 2, a foamed resin molding die A (conventional back plate) in which the support 5 was directly attached to the back plates 6 and 6 was used without using a protective material and a heat insulating material.
[0019]
(Comparative Example 2)
As shown in FIG. 3, a foamed resin molding die B provided with a rubber lining 15 having a thickness of 4 mm on the inner surfaces of the back plates 6 and 6 was used. However, the rubber lining 15 was not provided in the portion where the support 5 abuts, and the support 5 was directly applied to the back plates 6 and 6 for mounting.
[0020]
Using each of the foamed resin molds of these Examples and Comparative Examples 1 and 2, a foamed resin molded product made of a polystyrene resin was produced, and the temperature of the back plate 6 (° C.), the amount of steam used (kg / shot), The distortion amount t '(mm) of the heat insulating material and the thickness T (mm) of the bottom part of the molded product were measured and comparatively evaluated. The results are summarized in Table 1.
[0021]
[Table 1]

[0022]
From Table 1, it was confirmed that the foamed resin molds of the examples according to the present invention had better heat insulation effects than the foamed resin molds of Comparative Examples 1 and 2, and the amount of steam used could be reduced.
[0023]
(Insulation material compression test)
In a general foamed resin molding machine used for the production of a general-purpose polystyrene foamed resin molded product, the number of supports is about 20 to 30. For a φ25 support, 255 kg / cm ² per support is used. It receives a compressive force of about 170 kg / cm ² . The load is applied for about 80 seconds in one cycle of 120 seconds, and the remaining 40 seconds are open. In a structure in which a heat insulating material and a protective material are laminated between a back plate and a support as in the foamed resin mold of the present invention, if the heat insulating material does not have compression resistance, the heat insulating material in a portion corresponding to the support can be easily formed. As a result, the positions of the first and second molds cannot be adjusted by the support, and the molds are distorted, so that a molded article having a desired shape and dimensions cannot be obtained. Therefore, in the present invention, it is necessary to use a heat insulating material having compression resistance.
The compressive stress and strain of the asbestos used as the heat insulating material in the present invention and the rubber plate used as the heat insulating material in the prior art were measured for comparison. For the measurement, Tensilon UCT-5T manufactured by Orientec Co., Ltd. was used, and the load cell was TYPE UF-5 Cap. 5tf SER. NO. 049539 was used. The test environment was a temperature of 25 ° C. and a humidity of 50 RH%.
[0024]
{Circle around (1)} Asbestos-made joint sheet, plate thickness 1 mm (product No. # 1500, manufactured by Valqua Japan) (referred to as "asbestos sheet" in Table 2): 12 mm thick, 20 cm square aluminum plate (used for back plate) The asbestos sheet was placed on the same material (A5052), and an aluminum round bar (material A5052) having a diameter of 25 mm and a length of 37 mm used as a support material was sandwiched between the load cell and the sheet, and a compression test was performed.
[0025]
(2) Rubber plate, plate thickness 4 mm:
A compression test was performed on the same aluminum plate as in the above (1), which had been subjected to the same construction as the rubber lining (rubber plate thickness: 4 mm) applied to the back plate of the molding die, in the same manner as in the above (1).
With respect to the above (1) and ( ² ), the amount of distortion (mm) of the heat insulating material at a stress of 255 kgf / cm ² was measured, and the results are shown in Table 2 below. Table 2 also shows the thermal conductivity λ (W / m · k) of the heat insulating materials of (1) and (2).
[0026]
[Table 2]

[0027]
From the results in Table 2, it can be seen that the asbestos sheet has less distortion when compressed than the conventional rubber lining, and is suitable as the heat insulating material of the present invention. On the other hand, the rubber plate has a large amount of distortion, and in the structure in which the heat insulating material and the protective material are provided between the back plate and the support as in the present invention, the deformation amount is large when compression is applied, and the deformation and size of the molded product are large. Because of the possibility of change, it was not suitable as a heat insulating material used in the present invention.
[0028]
【The invention's effect】
Since the foamed resin mold of the present invention has a protective material and a heat insulating material laminated and arranged between the support and the back plate, the back plate can be insulated, and the support does not directly hit the back plate. The heat transfer to the back plate is blocked, the heat insulation of the steam chamber is increased, and the amount of steam used during molding can be reduced. In addition, the surface of the protective material is smooth, so that the steam drain and the cooling water easily fall off the surface, and the latent heat of evaporation of the adhering water during cooling in a vacuum is reduced, thereby suppressing unnecessary cooling.
Further, since the protective material protects the heat insulating material from being broken at the time of contact with the support and from being damaged, the life of the heat insulating material can be extended.
In addition, since the heat insulating material and the protective material can be laminated on the surface of the back plate and the support can be directly applied to the protective material, once these are attached, when replacing the first and second molding dies, this is used. The back plate to which the heat insulating material and the protective material are attached can be used in common, and unnecessary replacement work is not required. Further, the shield plate used in the prior art is not required, and an extra operation of replacing the shield plate at the time of replacing the first and second molds is not required.
Furthermore, when the protective material and the heat insulating material are sandwiched between the support and the back plate and attached, only the periphery of the protective material and the heat insulating material are tightly fixed. Since a slight air layer is formed between the heat insulating material and the protective material, a heat insulating effect exceeding the heat insulating effect of only the heat insulating material can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a main part showing an embodiment of a foamed resin mold of the present invention.
FIG. 2 is a cross-sectional view of a main part showing a structure of a foamed resin mold of Comparative Example 1 used for comparison in Examples.
FIG. 3 is a sectional view of a main part showing a structure of a foamed resin molding die of Comparative Example 2 used for comparison in Examples.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Foam resin mold 2 First mold 3 Second mold 4 Cavity 5 Support 6 Back plate 7 Protective material 8 Insulation material 9 Steam chamber 12, 13 Frame 14 Fixing bolt

Claims (3)

A first mold and a second mold provided with a plurality of steam holes, and a cavity formed by combining the first and second molds is filled with expandable resin particles; In the foamed resin mold for producing a foamed resin molded product, the steam is brought into contact with the foamable resin particles through the steam hole of
A foamed resin mold comprising a protective member made of a moisture-resistant hard material and a heat insulator made of a compression-resistant heat-insulating material laminated between a support of the mold and a back plate. The heat insulating material satisfies the relationship of t ′ / T ≦ 0.05, where t ′ (mm) is the amount of compressive strain of the heat insulating material, and T (mm) is the thickness of the bottom portion of the foamed resin molded product. The foamed resin mold according to claim 1, which is: The foamed resin mold according to claim 1, wherein the protective material and the heat insulating material are attached in a state in which the periphery thereof is tightly fixed to a back plate, and is sandwiched between the support and the back plate at a support contact portion. .

Images