JP2000296530A - Molded product expanded in mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a quality molded product expanded in a mold in which a packing density in each part of the molded product is secured properly. SOLUTION: Materialization can be performed in a molded product having a complex shape or a thin-wall part such as a foamed polyolefin resin molded product which is molded by an in-mold expansion forming method and in which the density of each part of the molded product is set up to be within ±5% of the average density, a molded product in which the degree of complex shape is set up at 1.1 or above, a molded product in which the thickness of a thin-wall part is set up at 3-10 mm, and a molded product in which the number of beads to be arranged in the thickness direction of a thin-wall part is set up to be three or below.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an in-mold foam molded article of a polyolefin-based synthetic resin obtained by an in-mold foam molding method.

[0002]

2. Description of the Related Art In an in-mold foam molding apparatus for producing a foam molded article by heating, foaming and fusing raw material beads made of a thermoplastic synthetic resin in a mold, a mold formed by a core mold and a cavity mold is used. The filling of the raw material beads into the space is basically carried out by flowing air into the molding space, and typical examples include a cracking filling method, a pressure filling method, and a compression filling method.

[0003] The cracking filling method is a method employed when air used for filling cannot be sufficiently exhausted only from vents such as a core vent and a core vent hole arranged in a core mold and a cavity mold. Do not completely close the core mold and cavity mold (cracking), for example, open only 10% of the bottom thickness of the molded product,
This is a method of discharging air used at the time of filling from the gap between the core mold and the cavity mold. In this filling method, since the core mold and the cavity mold are closed after filling the raw material beads, the density of the bottom of the molded product is higher than the other parts by the cracking gap. Further, when the shape of the molded article becomes complicated, the flow of air, which serves as a driving force for filling the raw material beads, fluctuates in each part in the cavity, and as a result, the packing density of the raw material beads also fluctuates in each part.

In the pressure filling method, the raw material beads to be filled are stored in a raw material tank pressurized in advance with air, the molding space is opened to the atmosphere while the mold is closed, and the differential pressure is used in the molding space. This is a method in which raw material beads are filled. The air flowing into the molding space at the time of filling is exhausted from core vents or core vent holes arranged in the core mold and the cavity mold. In this filling method, when the shape of the molded product becomes complicated, the filling density varies in each part of the molding space as in the cracking filling method described above. In the compression filling method, the raw material beads to be filled are stored in advance in a raw material tank pressurized with air, and in a state where the mold is closed, the inside of the molding space is pressurized to the same pressure as the raw material tank or to a lower pressure. The raw material beads are filled in the molding space. The raw material tank and the inside of the molding space are controlled to a set value during filling. In this filling method as well, if the shape of the molded product becomes complicated, the filling density fluctuates in each part of the molding space similarly to the cracking filling and the pressure filling described above.

[0005]

Generally, as a method of reducing the variation of the packing density in each part of the molding space, the number of used filling devices is increased. But,
There is a limit in increasing the number of fillers to be used. In addition, there may be a case where the packing density fluctuates, such as an instantaneous decrease in air pressure or insufficient exhaustion of air from the molding space. For this reason, the number of fillers used and the arrangement of the fillers are a source of concern for the mold designer, and there are many trial and error factors, making standardization extremely difficult. In particular, the packing density of the raw material beads in the part far from the filling device or in the narrow bottomed part tends to be low. Density needs to be high,
The weight of the molded article becomes heavier than when the density is uniform.

Considering the molding surface, it is necessary to foam the raw material beads in order to obtain a sufficient fusion of a portion having a low filling density by heating, so that the heating vapor pressure is increased. There is a need. Furthermore, in cooling, since the heating vapor pressure is increased in accordance with the portion having a low filling density, the portion having a high filling density is excessively heated, and the foaming pressure is higher than that in normal molding. It takes a long time to reduce the high foaming pressure to the foaming pressure at which the mold can be released, and the molding cycle is lengthened and productivity is reduced. Furthermore, since the foaming pressure of each part of the molded article at the time of heating and cooling becomes non-uniform, the releasability is poor, and since the filling property is poor, productivity and yield are reduced.

An object of the present invention is to provide a high-quality in-mold foam molded article in which the filling density in each part of the molded article is appropriately secured by the method for in-mold foam molding of a polyolefin-based synthetic resin.

[0008]

The in-mold foam molded article of the present invention is an in-mold foam molded article obtained by a method of in-mold foam molding of a polyolefin-based synthetic resin, and has an average density in each part of the molded article. It is set within ± 5% of the density. Conventionally, such a molded product was considered to be difficult to mold, but, for example, while adjusting the supply amount per unit time by adjusting means, raw material beads made of a polyolefin-based synthetic resin were converted into a core mold and a cavity mold. In the molding space formed by the above, at least 3 which communicates with the molding space while being supplied along with the flow of air for filling the molding space.
The air supplied to the molding space is discharged to the outside of the molding space via the air pressure regulating unit while controlling the internal pressures of the two air pressure adjusting units independently or in any combination by the control means, so that the inside of the molding space is It can be realized by a method of filling raw material beads. With this configuration, the cycle time of heating and cooling during molding can be shortened, and the strength and rigidity of the thin portion and the like can be sufficiently ensured while the molded product is made lightweight.

The density of each part of the molded article is defined as ±
As a specific configuration of a molded article that is preferably set within 5%, a numerical value obtained by dividing the surface area of the molded article by the volume is defined as a complex shape degree. The thickness of the thin portion of the molded product is set to 10 mm to 3 mm, or the thickness of the thin portion of the molded product is set to 10 mm to 3 mm. In addition, a molded article having a complicated shape or having a thin-walled portion such as one in which the number of beads arranged in the thickness direction of the thin-walled portion of the molded product is set to three or less is applied.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2, an in-mold foam molding apparatus 1 includes raw material beads in a molding space 4 formed by a core mold 2 and a cavity mold 3 arranged opposite to each other, and a core mold 2 and a cavity mold 3. And a steam supply means for heating, foaming and fusing the raw material beads 5 filled in the molding space 4 with steam, and a cooling means for cooling the molded product. I have.
Since the steam supply means and the cooling means have a well-known configuration,
A detailed description thereof will be omitted.

The core mold 2 and the cavity mold 3 are attached to a housing 12 having a frame-shaped frame 10 and a back plate 11, respectively. At the time of filling 5, air pressure adjusting sections 30 and 31 for discharging air supplied with the raw material beads 5 while adjusting the pressure are formed.
The air pressure adjusting units 30 and 31 heat the raw material beads 5,
It functions as a steam chamber for supplying steam to the molding space 4 at the time of foaming and fusion, and at the time of cooling the molded product, it is a cooling chamber for spraying cooling water from the back side to the core mold 2 and the cavity mold 3. Function as

The core mold 2 and the cavity mold 3 have the structure shown in FIG.
As shown in FIG. 3, a ventilation hole 15 including a core vent 13 and a core vent hole 14 is formed, and the molding space 4 and the air pressure adjusting units 30 and 31 are communicated through the ventilation hole 15. As shown in FIGS. 3 and 4, the core vent 13 is a member attached to the mounting hole 16 formed in the core mold 2 and the cavity mold 3, and has a through hole 17a having a diameter smaller than the diameter of the raw material beads 5 on the bottom surface. Alternatively, it is a bottomed cylindrical body formed with a plurality of thin slots 17b, and the core vent hole 13 is
As shown in FIG. 3, it is a through hole formed in the core mold 2 and the cavity mold 3 and having a diameter smaller than the diameter of the raw material beads 5.

[0013] Flanges 2a, 3a are formed at the outer edges of the core mold 2 and the cavity mold 3, and the flanges 2a, 3a are formed.
An air pressure adjusting portion 32 is formed between the a and a, which communicates with the molding space 4 via the clearance 18 between the core mold 2 and the cavity mold 3 in a closed state. The clearance 18 between the core mold 2 and the cavity mold 3 is set to be smaller than the diameter of the raw material beads 5, and when the raw material beads 5 are filled, only the air supplied to the molding space 4 together with the raw material beads 5 passes, The beads 5 are configured to remain in the molding space 4. The clearance 18 may be formed over the entire circumference of the core mold 2 and the cavity mold 3, or may be provided only locally at a necessary portion. Further, as shown in FIG. 5, a plurality of clearances 18 and air pressure adjustment units 32 (two in the illustrated example).
One).

The core mold 2 has a narrow bottomed hard filling portion 1.
9 are formed. However, as long as the portion where the raw material beads 5 are difficult to be filled is a portion formed on the cavity mold 3 side or a portion other than the portion shown in FIG.
It can be handled in the same manner as the difficult filling portion 19. For example, a remote portion separated from the filling device 21 such as the vicinity of the clearance 18 shown in FIG. The present invention can be similarly applied to a mold having no difficult-to-fill portion.

The bead filling means includes a raw material bead supply means for supplying raw material beads 5 by flowing air into the molding space 4, and an air supplied into the molding space 4 together with the raw material beads 5 to the outside of the molding space 4. There are four systems of air discharging means for discharging, and control means for controlling these four air discharging means independently. The raw material bead supply means will be described. As shown in FIG. 1, a raw material tank 20 for storing raw material beads 5 is provided.
An intake pipe P1 is connected to the middle of the intake pipe P1, and an intake valve V1 is interposed in the middle of the intake pipe P1, and the internal pressure of the raw material tank 20 is adjusted by controlling the intake valve V1.

A filler 21 opening to the molding space 4 is attached to the back plate 11 on the cavity mold 3 side. The filler 21 is connected to a raw material tank 20 via a filling tube 22 and is filled in the raw material tank 20. The raw material beads 5 are configured to be supplied from the filling device 21 into the molding space 4 along with the flow of air. The filling device 21 is connected to a filling air supply pipe P2, and is configured so that filling air at an appropriate pressure is supplied by a filling air valve V2 interposed in the middle of the filling air supply pipe P2.

An adjusting air supply pipe P7 is connected between a shutter 23 attached to the raw material tank 20 and the filling pipe 22, and the filling pipe is controlled by an adjusting air valve V7 provided at an intermediate portion of the adjusting air supply pipe P7. The configuration is such that the adjustment air of an appropriate pressure is supplied to 22. An adjusting means is constituted by the adjusting air supply pipe P7 and the adjusting air valve V7. The adjusting means supplies the raw material beads 5 from the raw material tank 20 to the filling pipe 22 while being diluted with the adjusting air. Further, by changing the supply amount of the conditioning air, the supply amount of the raw material beads 5 supplied to the filling tube 22 per unit time,
That is, the final dilution degree described later is adjusted. However, it is also possible to supply the raw material beads 5 from the raw material tank 20 to the filling tube 22 by a supply means such as a screw conveyor. In this case, the adjusting air valve V7 and the adjusting air supply tube P7 are omitted, By changing the rotation speed of the screw conveyor, the supply amount of the raw material beads 5 to the molding space 4 per unit time is adjusted.

The air discharging means will be described. The air pressure adjusting section 30 on the back of the core mold 2, the air pressure adjusting section 31 on the back of the cavity mold 3, and the flanges 2a, 3a of the core mold 2 and the cavity mold 3 are formed. Exhaust pipes P3 to P5 are connected to the air pressure adjusting unit 32, respectively.
Exhaust valves V3 to V5 are interposed in the middle of the process. An exhaust pipe P6 is connected to the inner part of the difficult filling portion 19, and an exhaust valve V6 is interposed in the middle of the exhaust pipe P6. With respect to the difficult filling portion 19, an air pressure adjusting portion 33 is formed in the exhaust pipe P6 upstream of the exhaust valve V6.

The air pressure adjusting section 30, the exhaust pipe P3 and the exhaust valve V3, the air pressure adjusting section 31, the exhaust pipe P4 and the exhaust valve V
4. The air pressure adjusting unit 32, the exhaust pipe P5 and the exhaust valve V5, and the air pressure adjusting unit 33, the exhaust pipe P6 and the exhaust valve V6 constitute four systems of air exhaust means. However, the air pressure adjustment unit 3
One of the air discharging means provided with the air pressure adjusting unit 33 and the air discharging means provided with the air pressure adjusting unit 33 may be omitted. Further, at least one of the air pressure adjusting units 30 to 32 may be divided into a plurality of spaces, and a plurality of systems of air discharging means may be provided, each of the plurality of spaces being an air pressure adjusting unit. Further, when there are a plurality of difficult filling portions 19, a plurality of systems of air discharging means may be provided in which exhaust pipes are respectively connected to the plurality of difficult filling portions.

A control means (not shown) for independently controlling the exhaust valves V3 to V6 is provided. When the raw material beads 5 are charged, the exhaust valves V3 to V6 are automatically controlled by the control means, and the air pressure adjusting unit 30 is controlled. To 33 are adjusted independently or in any combination. In this bead filling means, the filling air valve V2 is operated to supply the filling air from the filling air supply pipe P2 to the filling device 21, so that the flow of air from the raw material tank 20 to the molding space 4 in the filling pipe 22 is achieved. And the raw material beads 5 are filled along the flow. For this reason,
The internal pressure of the raw material tank 20 and the air pressure adjusting units 30 to 33 is
As long as the internal pressure of the raw material tank 20 is set to be equal to or higher than the internal pressures of the air pressure adjusting units 30 to 33, any of the open air state, the reduced pressure state, and the pressurized state may be set.

The material of the raw material beads 5 may be selected from polyolefin-based synthetic resin materials such as polyethylene and polypropylene, and copolymers containing these as main components, depending on the use conditions of the molded article to be produced. Resin materials and copolymers of these synthetic resin materials can also be employed. The expansion ratio of the raw material beads 5 is
Although it depends on the material of the raw material beads 5, it is preferably in the range of 3 to 150 times. Specifically, the raw material beads made of a polystyrene-based synthetic resin material are 3 to 100 times, preferably 3 to 80 times, and the raw material beads made of a polyolefin-based synthetic resin material are 3 to 90 times, preferably 3 to 6 times.
A 0-times one can be suitably used. The particle size is 1 to 10
Those having a range of mm can be suitably used. The polyolefin-based synthetic resin is softer and more flexible than the polystyrene-based synthetic resin, and has a higher gas permeability, so that the molding method as described above shows a good filling property. In addition, the shape of the raw material beads (pre-expanded particles) is more variable in the polyolefin-based synthetic resin, and is generally inferior to the raw material beads made of the polystyrene-based synthetic resin in the mold filling property. In view of this, the raw material beads made of the polyolefin-based synthetic resin show better filling properties by the molding method described above or below, and the in-mold foam molded article of the present invention can be obtained. .

Next, an example of a method for filling the raw material beads 5 using the in-mold foam molding apparatus 1 will be described. In addition,
As PP material beads, those obtained by foaming Sumika Noblen (trade name) having a melting point of about 142 ° C., an MFR of about 8.5, and a particle weight of about 1.3 mg 45 times on average were used.
First, the core mold 2 and the cavity mold 3 are closed, and the inside of the raw material tank 20 is pressurized in advance with air.
Air pressure is applied to the molding space 0 to 33 and the molding space 4 in advance. The degree of the pressure in the air pressure adjusting units 30 to 33 and the molding space 4 at this time should be adjusted according to the difficulty of filling.

Next, the filler of the filling device 21 and the shutter 2
3. Open the filling air valve V2 and the regulating air valve V7 to start filling the raw material beads 5. The filling air pressure at the filling air valve V2 is at least 2 kg /
cm ² or more, and set to 4 kg / cm ² or more in absolute value.

During filling, the raw material beads 5 are stored in the raw material tank 2
0, and the compressed air from the regulating air valve V7,
In addition, it flows into the molding space 4 while being diluted with the compressed air from the filling air valve V2. At this time, the volume ratio between the air flowing into the molding space 4 and the raw material beads 5 is defined as a value obtained by dividing the volume of the air supplied to the molding space 4 by the volume of the raw material beads 5 as the final dilution degree. The final dilution degree is set to be 5 or more, preferably 10 to 50. If the final dilution degree of the raw material beads 5 is larger than 50, the amount of the raw material beads 5 to be filled per unit time decreases, so that the charging takes time, the molding cycle time increases, and the air consumption increases. Problem. On the other hand, if the final dilution degree is less than 10, the raw material beads 5 in the filling tube 22, the filling device 21 or the molding space 4.
Since the number of times of contact or collision between each other increases, there is a problem that the resistance that hinders the filling of the raw material beads 5 increases, and there is a problem that the raw material beads 5 impede the flow of air and thus cannot be filled well. Therefore, it is preferable to set 10 to 50. However, when the raw material beads 5 are supplied by a supply means such as a screw conveyor, the rotation speed of the screw conveyor is controlled so that the final dilution degree becomes a desired value, and the raw material beads 5 with respect to the molding space 4 are formed.
Is set for the supply amount per unit time.

Thus, the compressed air flowing into the molding space 4 passes through the ventilation holes 15 and the clearances 18 to increase the pressure of the air pressure adjusting units 30 to 33. At this time, by controlling the pressures of the air pressure adjusting units 30 to 33 individually or by combining any of them using the exhaust valves V3 to V6,
The raw material beads 5 are first filled in the portion where the raw material beads 5 are difficult to be filled, so that the variation in the density in each part of the molded product can be suppressed, and the filling density can be appropriately secured.

For example, the configuration is such that the exhaust valves V3 to V6 are opened when the internal pressure of the air pressure adjusting units 30 to 33 becomes higher than the set pressure, and the set pressure is adjusted to the air pressure adjusting unit 30>
Air pressure adjusting unit 31> Air pressure adjusting unit 32> Air pressure adjusting unit 3
3, the exhaust valve V6 is first opened and the difficult filling portion 19 is opened.
Are filled with the raw material beads 5, and the filling of the raw material beads 5 into the difficult filling portion 19 is substantially completed.
When the internal pressure of 2 increases, the exhaust valve V5 is opened, and the outer edge of the molding space is filled with the raw material beads 5. In this way, the exhaust valves are opened in order from the one with the smaller set pressure, and the molding space 4 is filled with the raw material beads 5. Also,
As another control method, the filling step is divided into four steps. In the first step, only the exhaust valve V6 is used to control the air pressure of the air pressure adjusting unit 33, and in the second step, the exhaust valves V5 and V6 are controlled. To control the air pressure of the air pressure adjusting units 32 and 33, and in a third step, the air pressure adjusting unit 3 is controlled by using the exhaust valves V4 to V6.
In the fourth step, the exhaust valve V is controlled.
The raw material beads 5 are sequentially filled into the molding space 4 while controlling the air pressure of the air pressure adjusting units 30 to 33 using 3 to V6.

After filling the raw material beads 5 in this manner, the filler of the filling device 21 is closed and the adjusting air valve V7 is closed, and the raw material beads 5 remaining in the filling device 21 and the filling tube 22 are filled with the raw material beads using the filling air. The charging cycle is completed by returning the tank to the tank 20 and then closing the charging air valve V2 and the shutter 23, and a series of normal forming steps of heating, cooling and release are sequentially performed to obtain a predetermined molded product.

The molded article molded in this way has, for example, a complex shape degree obtained by dividing the surface area of the molded article by the volume of 1.1 or more, preferably 1.2 or more, more preferably 1.3 or more. Complex shape or 10m thick
Conventional packing such as those having a thin portion of m to 3 mm, preferably 8 to 3 mm, more preferably 6 to 3 mm, or those having three or less beads arranged in the thickness direction of the thin portion of the molded product. Even in the case of a molded article considered to be difficult, the density in each part is set within ± 5% of the average density, preferably within ± 4%, more preferably within ± 3%. It is a good quality molded product with little quality. As described above, the molded article of the present invention exerts its original effect in a molded article having a complicated shape in which a thick portion and a thin portion are shared, and is often industrially useful.

Next, a description will be given of a quality evaluation test of a molded article molded by filling the raw material beads 5 by the above-mentioned filling method. In manufacturing the molded article 40 having the shape as shown in FIGS. 6 and 7, the method of filling the raw material beads 5 by the cracking filling method, the pressure filling method, the compression filling method, and Raw material beads 5 by the filling method of the invention
Four filling method when filled with the raw material bead 5 is filled to prepare a four moldings 40, as shown in FIG. 7, the distal end portion 42 of the partition wall 41 of the molded product 40 middle section 43
And the density at the base end 44 were measured, and the results shown in Table 1 were obtained.

[0030]

[Table 1]

As shown in Table 1, in the molded article manufactured by filling the raw material beads 5 by the conventional filling method, the partition wall 41 was used.
The density decreases from the base end portion 44 to the tip end portion 42 side, whereas the molded product manufactured by filling the raw material beads 5 by the filling method of the present invention has a substantially uniform density. It turns out that there is. That is, in the filling method of the present invention,
It can be seen that a high-quality molded product with little variation in density can be manufactured. Further, in the conventional molded product, it is necessary to design the molded product based on the low density portion so that sufficient strength can be obtained even in the low density portion, and there is a problem that the molded product becomes heavy. In the molded article of the present invention, the density in each part of the molded article is substantially uniform, so that the molded article can be made lightweight while ensuring the strength of the molded article, and the amount of the raw material beads 5 used can be reduced. As a result, the production cost of the molded product can be reduced.

In this embodiment, the internal pressures of the air pressure adjusting units 30 to 33 are adjusted so that the density of each part of the molded article becomes uniform. It is also possible to increase the packing density. Further, the present invention can of course be applied to a case where a molded article having various shapes other than the molded article 40 is molded.

[0033]

According to the in-mold foam molded product according to the first aspect, since the density of each part of the molded product is set within ± 5% of the average density, the cycle time of heating and cooling during molding can be reduced. It is possible to reduce the length and to secure sufficient strength and rigidity in a thin-walled portion while making the molded product lightweight.

More specifically, the numerical value obtained by dividing the surface area of the molded product by the volume is defined as a complex shape degree, and the complex shape degree is set to 1.1 or more. According to the third aspect, the thickness of the thin portion of the molded product is set to 10 mm to 3 mm, and as in the fourth aspect, the beads are arranged in the thickness direction of the thin portion of the molded product. In the case where the number is set to three or less, the shape is complicated or has a thin portion, and conventionally it was considered that molding was difficult.
It can be set within 5%.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an in-mold foam molding apparatus.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a longitudinal sectional view showing the vicinity of an air hole.

FIG. 4 is a front view of a core vent.

FIG. 5 is a diagram corresponding to FIG. 2 of another in-mold foam molding apparatus.

FIG. 6 is a perspective view of a molded product.

FIG. 7 is a longitudinal sectional view of a molded product.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 In-mold foam molding apparatus 2 Core mold 2a Flange part 3 Cavity mold 3a Flange part 4 Molding space 5 Raw material beads 10 Frame-shaped frame 11 Back plate 12 Housing 13 Core vent 14 Core vent hole 15 Vent hole 16 Mounting hole 17a Through hole 17b Groove holes 18 clearance 19 flame filling unit 20 feed tank 21 filling 22 filling tube 23 shut <br/> te 30 air pressure adjusting unit 31 pneumatic adjusting unit 32 air pressure adjusting unit 33 air pressure adjustment unit P1 intake pipe V1 intake valve P2 filling the air supply Pipe V2 Filling air valve P3 Exhaust pipe V3 Exhaust valve P4 Exhaust pipe V4 Exhaust valve P5 Exhaust pipe V5 Exhaust valve P6 Exhaust pipe V6 Exhaust valve P7 Adjustment air supply pipe V7 Adjustment air valve 40 Molded product 41 Partition wall 42 Tip section 43 Middle section 44 Base end

Continuing from the front page (72) Inventor Tomio Nakajima 2-25 Komabacho, Nakatsugawa City, Gifu Prefecture Daisen Industry Co., Ltd. (72) Inventor Kiyotaka 2-25 Komabacho Nakatsugawa City, Gifu Prefecture Daisen Industry Co., Ltd. (72 Inventor Masahiko Samejima 5-3-31-104 Torikai Nishi, Settsu-shi, Osaka (72) Inventor Yoshiyuki Kobayashi 1-11-1-1, Fujii, Oji-cho, Kitatsukatsuragi-gun, Nara (72) Inventor Kenji Yamaguchi Shimahonmachi, Mishima-gun, Osaka 2-3-3 Wakayamadai 202 F term (reference) 4F212 AA03 AG20 UA01 UB01 UC06 UF01 UF30 UF31 UF34 UF49 UK09

Claims (4)

[Claims] 1. An in-mold foam molded article obtained by an in-mold foam molding method of a polyolefin-based synthetic resin, wherein the density of each part of the molded article is set within ± 5% of the average density. In-mold foam molded product. 2. The complex shape degree is defined as a value obtained by dividing the surface area of the molded product by the volume, and the complex shape degree of the in-mold foam molded product is set to 1.1 or more. 2. The in-mold foam molded article according to 1. 3. The thickness of the thin part of the molded product is from 10 mm to
3. The in-mold foam molded product according to claim 1, wherein the product is set to 3 mm. 4. The in-mold foam molded product according to claim 1, wherein the number of beads arranged in the thickness direction of the thin portion of the molded product is set to three or less.