JP2000168853A - Synthetic resin-made heat-insulated container, and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily manufacture a synthetic resin container which is high in both strength and heat insulation by providing a cavity which is formed upwardly from a bottom integrated with a side wall inside it. SOLUTION: A synthetic resin heat-insulated container has at least a bottom part and a side wall integrated with the bottom, and a cavity 10 with heat insulation function is formed inside the bottom and the side wall. The heat insulation effect is demonstrated by forming the cavity 10 inside the side wall so that the container can be held by hand. A plurality of stripes upwardly from the bottom are preferably provided for the cavity 10 formed inside the side wall. Since the cavity 10 is formed inside the side wall and the bottom of the container, high heat insulation can be demonstrated. The container is preferably manufactured using a so-called gas injection molding method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat insulating container and a method for producing the same.

[0002]

2. Description of the Related Art There are various types of heat-insulating containers for holding food and drink such as ramen and udon for keeping the contents warm and preventing burns when touching the containers. As such, synthetic resin insulation containers made of expanded polystyrene or the like are widely used.

[0003]

However, conventional containers made of simply expanded polystyrene have not always had sufficient heat insulating properties. Therefore, as a method of exhibiting higher heat insulating properties, it is conceivable to form a hollow portion in the side wall portion or the like with a double structure of the container, but molding a container having a hollow portion in the side wall portion using expanded polystyrene. Then, the strength is insufficient. For that reason,
For example, there have been problems such as deterioration in handling properties during use, breakage during transportation, and collapse of the container during printing on the side wall. Japanese Patent Application Laid-Open No. 10-35744 discloses an insulated container having improved heat insulating properties while maintaining strength and the like. However, the present invention merely provides an improved heat insulating property for only the bottom of the container. Absent. In addition, it is difficult at present to recycle expanded polystyrene, and used containers cause enormous generation of dust, which is not preferable in terms of environmental problems. In addition, there is a concern that unsanitary components may elute when hot water is contained in the container. Furthermore, a method for easily producing a container having a double structure by integral molding has not been found.

[0004] The present invention has been made to solve the above problems, and an object of the present invention is to provide a synthetic resin container exhibiting both high strength and heat insulation and a method for easily manufacturing the container. It is intended to provide a container excellent in environmental and sanitary aspects.

[0005]

In the heat insulating container made of synthetic resin according to the present invention, a cavity formed upward from a bottom integrated with the side wall is formed inside the side wall. Or a gap formed radially from the center of the bottom inside the bottom, or a gap formed radially extending from the center of the bottom inside the bottom, In the inside of the portion, there is formed a gap formed upwardly in communication with the gap in the bottom. Here, it is preferable that a thick region and a thin region are formed on the side wall and / or the bottom, and a void is formed inside the thick region. It is desirable that the void portion is constituted by a plurality of streaks. It is desirable that unevenness caused by the formation of the thick region and the thin region is formed on the inner wall surface, and the outer wall surface of the side wall is smooth. The synthetic resin heat insulating container of the present invention is desirably made of a non-foamed material,
Further, it is desirable to be made of an olefin resin. Further, the synthetic resin heat insulating container of the present invention is desirably integrally formed by a gas injection molding method.

The method of manufacturing a synthetic resin heat insulating container of the present invention is characterized in that a container having a cavity formed in a side wall and / or a bottom is formed by a gas injection molding method. At this time, it is desirable to form a thick region and a thin region on the side wall and / or the bottom. It is also desirable to increase the cavity volume during shaping. Furthermore, it is desirable to dispose a low thermal conductivity material in a mold portion corresponding to a void formed in a container to be molded.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The heat insulating container made of synthetic resin of the present invention comprises:
It has at least a bottom portion and a side wall portion integrated with the bottom portion, and a void portion having a heat insulating function is formed inside the bottom portion and / or the side wall portion.
In particular, in making it possible to hold the container by hand,
It is desirable to form a void inside the side wall to exhibit a heat insulating effect. As shown in FIGS. 1 and 2, for example, as shown in FIGS. 1 and 2, the gap formed inside the side wall is formed by forming a plurality of gaps 10 formed in the streak upward from the bottom. It is suitable. However, it is not always necessary to be clearly independent of a plurality of gaps. For example, as shown in FIGS. 3 and 4, an irregularly shaped gap 14 or an annular gap 16 as shown in FIG. It may be.
When such an annular space 16 is formed, the space is excellent in terms of heat insulation, but disadvantageous in terms of strength. It is desirable to form a portion having no void portion as appropriate.

The shape of the side wall does not need to be cylindrical. For example, as shown in FIG. 6, the inner wall 18 is formed in a polygonal shape, and as shown in FIG. A polygonal shape or a polygonal inner and outer wall surface may be used. 6 to 10, 12 to
As shown in FIG. 13, the width (wall thickness) of the side wall portion is not constant,
It is also preferable to have a thick region 22 having a relatively large thickness and a thin region 24 having a relatively small thickness. In this case, the void portion 26 may be formed in the thick region 22. desirable.
By forming the thick region 22, the thick region 22 functions as a rib, and exhibits an effect of improving strength. Further, since the thin region is filled with the resin, the strength can be maintained high. Further, even when the wall thickness is not uniform, the strength can be made uniform at a high level by forming a void in the thick wall area, for example, when printing on the outer wall surface of the side wall portion. In addition, problems such as collapse of the container can be avoided. In addition, as described above, the thick region 22
When the thin region 24 is formed, the thin region 24 is
Since it does not contribute to heat insulation, the area is preferably smaller. In addition, when the container is grasped by a person, there is a tendency to naturally grasp the thick region, and even if a partially thin region is formed, the effect of preventing a burn or the like is remarkably exhibited. Further, even when the thick region 22 and the thin region 24 are formed on the side wall portion, unevenness caused by the formation of the thick region and the thin region, as shown in FIGS. By forming so as to appear only on the inner wall surface side, the outer wall surface of the side wall portion can be made smooth, and printing processing on the outer wall surface of the side wall portion is not hindered.

Further, as shown in FIG. 10, it is preferable to form a void portion 34 inside the bottom portion 28 in order to exhibit heat insulation at the bottom portion 28. In that case, in addition to keeping the surface of the bottom portion 28 flat as shown in FIG. 10, a thick region 32 is formed in the bottom portion 30 as shown in FIG. It is preferable to form a part. Also, when forming a void at the bottom,
From the viewpoint of the strength balance and the like, it is desirable to form the gap so as to extend radially from the center of the bottom. Further, the void may be formed only at the bottom, but it is desirable to form the void at both the side wall and the bottom. In that case, as shown in FIGS. 10 to 12, the void is formed at the bottom. It is desirable that the gap be communicated with the gap formed in the side wall. The hollow ratio by forming the void portion is 1 to
In terms of enhancing heat insulation, a higher value is preferable, but it is set according to the required strength, application, and the like.

The container of the present invention has such a side wall and / or
Alternatively, since a void portion is formed inside the bottom portion, high heat insulating properties can be exhibited. In particular, by forming a thick region and a thin region on the side wall and / or the bottom and forming a void inside the thick region, the heat insulation can be improved while maintaining high strength. In addition, a container having such a structure exhibits sufficient heat insulating properties without using a foamed material, so that the strength is increased by using a non-foamed material, and handleability during use is deteriorated, Also,
Problems such as cracks during transportation and collapse of the container during printing on the side wall can be avoided.

The heat-insulating container of the present invention can be made of any synthetic resin applicable to injection molding. An olefin resin having excellent characteristics such as strength, light weight, low cost, hygiene, and recyclability can be used. Resins are preferred. Examples of such olefin-based resins include ethylene-based resins, for example, high-medium-low-density polyethylene, ethylene-vinyl acetate copolymer,
Ethylene / ethyl acrylate copolymer, ethylene / methyl acrylate copolymer, ethylene / α-olefin copolymer rubber, polybutene-1, poly-4-methylpentene-1 copolymer, polypropylene resin or a mixture thereof No. Among these, a polypropylene resin is the most preferable, but a polyethylene resin is also preferable. Among them, high-density polyethylene is particularly excellent in heat resistance and hygiene and is suitable for a heat insulating container for food.

Further, the polypropylene resin is excellent in various workability including a gas injection molding method to be described later, and has heat resistance,
It is particularly preferably used in the present invention because of its excellent rigidity, strength, hygiene, and recyclability. The polypropylene resin used in the present invention includes, for example, a transition metal compound such as a titanium compound or a transition metal compound supported on a carrier such as a magnesium compound, and a catalyst system obtained from an organometallic compound such as an organoaluminum (so-called Zigler-Natta). Propylene) or a random copolymer or a block copolymer of propylene and ethylene and / or an α-olefin having 4 to 12 carbon atoms in the presence of a metallocene-based catalyst which has recently been put into practical use. Is preferred. Specific examples of the α-olefin include 1-butene, 1-hexene, 1-octene, 3-methyl-1-butene, 3-methyl-1-pentene, 4-methyl-1-pentene, and 4-dimethyl-1. Pentene, vinylcyclopentane, vinylcyclohexane and the like are used. These α-olefins can be used alone or in combination of two or more. In addition, various thermoplastic resins such as olefin resins such as high-medium low-density polyethylene, polybutene-1, poly4-methylpentene-1, and ethylene / α-olefin copolymer rubber can be blended with the polypropylene resin.

As described above, in the heat insulating container of the present invention, since an olefin-based resin can be appropriately used instead of expanded polystyrene, recyclability can be improved, and it is desirable from the viewpoints of environment, hygiene and the like. It is what is done.
The resin material used to mold these heat-insulating containers includes talc for improving heat resistance, inorganic fillers such as charcoal, or, if necessary, various organic-inorganic fillers, nucleating agents, pigments, Stabilizers and the like can be added. Also,
The heat-insulating container of the present invention exhibits high heat-insulating properties due to its structure, and thus exhibits a high heat-insulating effect even by using a non-foaming material. However, a foaming agent is added as a resin material to be used. By applying the foamed material, a higher heat insulating effect can be exhibited, although the strength is disadvantageous. Furthermore, as described later, the heat insulating container made of synthetic resin of the present invention can be manufactured very easily by integral molding by applying a gas injection molding method.

The container of the present invention is desirably manufactured using a so-called gas injection molding method. The gas injection molding method is a molding method described in, for example, Japanese Patent Application Laid-Open No. Sho 54-111557, and after a sufficient amount of molten resin is injected into the cavity of a molding die to fill the cavity. And forming a hollow portion inside the molded article by further injecting gas into the molded article. As the gas, in addition to air, an inert gas such as a nitrogen gas, a carbon dioxide gas, and a helium gas is preferable.
A method for manufacturing the heat insulating container of the present invention will be described with reference to FIG. In the mold 40 used in the method of the illustrated example, a gate 44 for injecting resin is formed in a cavity 42 having a predetermined shape at a position corresponding to the outer center of the bottom of the container. Gas injection path 4 at 46
8 are connected. To mold, first, FIG.
As shown in (2), a predetermined resin material is injected from the gate 44 into the cavity 42. Then, when a predetermined amount of resin material that completely fills or slightly lacks the cavity 42 is injected into the cavity 42, gas is injected from the gas injection path 48 into the cavity 42, as shown in FIG. inject. Then, the gas supplies the resin material to the cavity 42.
To form a container having a cavity formed in the bottom and side walls.

The gas injection path does not have to be connected to the resin injection path from the lateral direction. Instead, the gas injection path is provided in parallel with the resin injection path, or as shown in FIG.
In the cavity corresponding to the center inside the bottom of the container,
The gas injection path 50 can be directly provided. Such a method for manufacturing a heat-insulating container by gas injection molding is particularly suitable for manufacturing a heat-insulating container having the above-described thin-walled region and a thick-walled region in which a void is formed. This is because, in the case where a radial thick region is provided at the bottom of the container, by providing a gate at the center of the bottom and providing a radial thick region therefrom, particularly in the gas injection molding method, cooling of the thick region is delayed. Because the resin maintains fluidity even at the time of gas injection, gas flows easily along the thick region, and voids are formed not only on the bottom surface but also on the side wall along the thick region. Because it is done. According to the method of the present invention, it is possible to produce a container exhibiting a heat insulating effect by simply and integrally forming a cavity in the side wall and / or the bottom of the container described above. Further, since the resin material is pressed against the cavity surface from the inside by injecting gas, the molding accuracy is high, the transferability from the cavity surface is excellent, and a pattern or the like is easily added to the outer surface of the container.

In this gas injection molding, it is desirable to increase the cavity volume during the shaping. As a method for increasing the cavity volume, for example, a mold enlarging method as shown in FIG. 16 is simple. This method utilizes a mold 56 in which a movable member 52 is provided in at least a part of a cavity 54. As shown in FIG. 16A, the shape of the cavity 54 is the shape of the original container to be molded. In this state, the resin material is injected in a state where the movable member 52 is disposed, and thereafter, as shown in FIG. 16B, gas is injected and the movable member 52 is moved backward (rightward in FIG. 16). )
The volume of the cavity 54 is increased. Thus, by increasing the volume of the cavity 54 during shaping,
It becomes easy to inject gas smoothly, and it becomes easy to form a larger void.

As a means for increasing the cavity volume during shaping, a resin discharging method is also simple. As shown in FIG.
Is formed using a mold 58 provided with a movable member 62. As shown in FIG. 17A, the movable member 62 allows the cavity 60 and the preliminary chamber 6 to be communicated with each other.
After the resin material is injected into the cavity 60 in a state in which the movable member 62 is separated, the movable member 62 is injected.
Is retracted to allow the cavity 60 and the preliminary chamber 64 to communicate with each other and to expel an amount of resin material corresponding to the gas injection into the preliminary chamber 64, thereby substantially increasing the volume of the cavity. According to this method as well, the gas can be smoothly injected into the cavity, so that a larger gap can be easily formed. Unnecessary resin members generated by the mold enlargement method or the resin discharge method may be separated from the molded container and discarded.

Furthermore, by partially disposing the low thermal conductivity material in the mold used for molding, the formation position of the void can be controlled. For example, as in a mold 66 shown in FIG. 18, a low thermal conductivity material 70 having a predetermined streak shape is buried in the cavity surface 68, and a mold in which a portion having low thermal conductivity is partially formed is used. When the above-described gas injection molding is performed, when the resin material is injection-molded, the resin is hardly cooled on the low thermal conductivity material 70, and the softened state is maintained as compared with other places. The gas injected into the resin flows in the resin along the soft material, that is, the low thermal conductivity material 70. As a result, the low thermal conductivity material 7
Since a void having a shape along 0 is formed,
By adjusting and arranging the low thermal conductivity material 70, it is possible to guide and control the formation position of the gap, and the gap can be stably formed as designed. The low thermal conductivity material refers to a member having a relatively lower thermal conductivity than the other part of the cavity surface of the mold used for molding, for example, a bake material, an epoxy resin, a polyimide resin, a silicone resin,
What consists of a tetrafluoroethylene resin, a ceramic, etc. can be applied.

[0019]

[Example 1] Fig. 6 shows the side wall of the container.
As shown in FIG. 11, a thick region 22 and a thin region 24 are provided, and the cross-sectional shape of the outer wall surface is circular. As shown in FIG.
A cavity having a shape for molding a container in which 32,... Are formed, and a mold as shown in FIG.
As a resin material, a block copolymer of polypropylene (MFR (230 ° C.): 30 g / 10 min, “J-Allomer PM970A” manufactured by Nippon Polyolefin Co., Ltd.) is used, which is heated to 230 ° C. and melted. Then, when a small amount was injected to fill the cavity, nitrogen gas was injected at 10 MPa to form an insulated container having a void. The thinnest part of the container was 1.5 mm, and the thickest part was 2.5 mm. In the obtained heat-insulating container, voids were formed in each thick-walled region, and the heat-insulating container could be held by hand with hot water contained therein, and exhibited sufficient heat-insulating properties when used. Further, in addition to the thick region 22 functioning as a rib, a thin region in which the resin is densely filled is also formed, so that it has sufficient strength.

Example 2 A mold having a cavity for forming a container in which the thickness of the side wall and the bottom was uniform was used, and the above-described mold as shown in FIG. 14 was used. Using the resin material of Example 1, in the same manner as in Example 1, a resin was injected into a mold, and nitrogen gas was injected to mold a heat-insulated container having a void. In this insulated container, FIGS.
As shown in the figure, since the void portion 14 is formed partially and widely inside the bottom portion and the inside of the side wall portion of the container,
Although it exhibited high heat insulation, the strength was somewhat reduced.

[Embodiment 3] As shown in FIGS. 9 and 10, there is a cavity for forming a container in which the side wall portion is composed of a thick region 22 and a thin region 24, and the surface of the bottom portion 28 of the container is flat. A mold as shown in FIG. 14 described above was used. Using the resin material of Example 1, in the same manner as in Example 1, a resin was injected into a mold, and nitrogen gas was injected to mold a heat-insulated container having a void. In this heat insulating container, a void is formed in the thick region 22, and inside the bottom 28,
Since the radially extending void portion 34 is formed,
The hot water could be held by hand with the hot water contained in the heat insulating container, and sufficient heat insulation was exhibited during use. Also,
In addition to the thick region 22 functioning as a rib, a thin region 24 that is densely filled with resin is also formed, and thus has sufficient strength.

Example 4 A container having the same cavity as that of Example 1 and a resin discharging mold as shown in FIG. 17 was molded. With the movable member 62 closing the preliminary chamber 64, the same resin material as in the first embodiment is injected into the cavity 60, and after the filling of the resin is completed, the movable member 62 is moved to make the preliminary chamber 64 communicate with the cavity 60. Then, nitrogen gas was injected at 10 MPa, and a part of the resin in the cavity 60 was extruded into the preliminary chamber 64 to form a container. In the obtained container, the gap was larger than in the container of Example 1, and the heat insulating property was further improved. Further, in addition to the thick region 22 functioning as a rib, a thin region in which the resin is densely filled is also formed, so that it has sufficient strength.

Example 5 A container having the same cavity as that of Example 2 and a mold of a mold enlarging system as shown in FIG. 16 was molded. The same resin material as that of the first embodiment is injected into the cavity 54, and after the filling of the resin is completed, the movable member 52 is moved to expand the volume of the cavity, and a part of the resin is injected by injecting nitrogen gas at 10 MPa. The container was extruded into the spread portion to form a container. In the obtained container, the gap was larger than in the containers of Examples 1 and 2, and the heat insulating property was further improved.
The strength was slightly lower than that of the container of Example 2.

Embodiment 6 As shown in FIGS.
A container having a cavity having a shape in which a thick region was formed on the side wall portion and the bottom portion was formed using a mold of a mold expanding system as shown in FIG. The same resin material as that of the first embodiment is injected into the cavity 54, and after the filling of the resin is completed, the movable member 52 is moved to expand the volume of the cavity, and a part of the resin is injected by injecting nitrogen gas at 10 MPa. The container was extruded into the spread portion to form a container. The injected gas mainly entered the thick region 22, and in the obtained container, a large void portion 26 was formed in the thick region 22, thereby exhibiting high heat insulation. Further, in addition to the thick region 22 functioning as a rib, a thin region in which the resin is densely filled is also formed, so that it has sufficient strength.

Example 7 Azodicarbonamide was added as a foaming agent to a resin material, and thick regions 22, 22,... Bulging inward were formed on the side wall as shown in FIG. Example 6 is the same as that of Example 6 except that the bottom has a container-shaped cavity in which thick regions 32, 32,... Extending radially from the center are formed as shown in FIG.
In the same manner as in the above, an insulated container was formed. The injected gas mainly entered the thick regions 32 and 22, and in the obtained container, large voids 26 were formed in the thick regions 32 and 22 and exhibited extremely high heat insulating properties. Also,
Since a thin region without voids was also formed in addition to the thick region 22 functioning as a rib, it also had high strength.

Embodiment 8 FIG. 16 is similar to Embodiment 5 except that a bake material is buried as a low thermal conductivity material and a mold provided with a low thermal conductivity material as shown in FIG. 18 is used.
A container was molded using a mold of a mold enlargement system as shown in FIG. The same resin material as in the first embodiment is injected into the cavity 54, and after filling of the resin is completed, the movable member 52 is moved to increase the volume of the cavity, and the nitrogen gas is supplied at 10MPa.
A container was formed by injecting the resin in a and extruding a part of the resin into the spread part. In the obtained container, the void portion of the streak is formed up to the vicinity of the upper portion of the side wall portion along the low thermal conductivity material formed in the cavity, and the heat insulating property is slightly improved as compared with the container in Example 2, Also, it had high strength.

Comparative Example 1 A container was molded in the same manner as in Example 1 except that normal injection molding was performed using the same mold as that in Example 1. If hot water was contained in the obtained container, it was hot and the side of the container could not be grasped by hand. Comparative Example 2 A container was formed in the same manner as in Comparative Example 1, except that azodicarbonamide was added as a foaming agent to the resin material. When hot water was contained in the obtained container, although it was somewhat improved over the container of Comparative Example 1, it was still hot and the side of the container could not be gripped by hand. Comparative Example 3 A container was formed in the same manner as in Example 2 except that normal injection molding was performed using the same mold as that in Example 2. If hot water was contained in the obtained container, it was hot and the side of the container could not be grasped by hand.

Table 1 summarizes the evaluation of heat insulation and rigidity of each container.
Shown inside. In Table 1, the evaluation of the heat insulating property is indicated by A for very good, B for good, C for insufficient heat insulating, and D for little heat insulating. Are indicated by a, those that do not cause any inconvenience are indicated by b, and those that are insufficient are indicated by c.

[0029]

[Table 1]

[0030]

According to the heat insulating container made of synthetic resin of the present invention, since a void is formed inside the bottom and / or the side wall, a high heat insulating function is exhibited without using a foam material. In particular, when the voids are formed in the streaks, high strength is exhibited together with heat insulation. Furthermore, if the thick region has a thick region and a thin region, and a void portion is formed in the thick region, the thick region functions as a rib and exhibits uniform and high strength. Also, since the thin region is filled with resin, the strength can be maintained high, for example,
At the time of printing on the outer wall surface of the side wall portion, problems such as collapse of the container can be avoided. Further, even when a thick region and a thin region are formed in the side wall portion, the unevenness caused by the formation of the thick region and the thin region is formed so as to appear only on the inner wall surface side. Accordingly, the outer wall surface of the side wall portion can be made smooth, and printing processing on the outer wall surface of the side wall portion is not hindered. Further, by using an olefin resin, it has excellent points such as strength, light weight, low cost, hygiene, and recyclability.

The container of the present invention can be manufactured very easily by integral molding by utilizing the gas injection molding method. At that time, by increasing the cavity volume during the shaping, the gas can be smoothly injected, and a larger void can be easily formed, and the heat insulating effect can be improved. Furthermore, by partially disposing the low thermal conductivity material in the mold used for molding, the formation position of the void can be controlled, and the void can be formed stably as designed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an example of the container of the present invention.

FIG. 2 is a perspective view of the container.

FIG. 3 is a perspective view showing an example of another container.

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3;

FIG. 5 is a cross-sectional view showing an example of another container.

FIG. 6 is a cross-sectional view showing an example of another container.

FIG. 7 is a cross-sectional view showing an example of another container.

FIG. 8 is a cross-sectional view showing an example of another container.

FIG. 9 is a cross-sectional view showing an example of another container.

FIG. 10 is a perspective view of the container.

FIG. 11 is a perspective view showing an example of the container of the present invention.

FIG. 12 is a perspective view showing an example of another container.

FIG. 13 is a sectional view taken along line XIII-XIII of FIG.

FIG. 14 is a process chart showing an example of the method for producing a container of the present invention.

FIG. 15 is a cross-sectional view illustrating an example of a mold used in the method for manufacturing a container of the present invention.

FIG. 16 is a process chart showing an example of the method for producing a container of the present invention.

FIG. 17 is a process chart showing an example of the method for producing a container of the present invention.

FIG. 18 is a perspective view showing an example of a mold used in the method for producing a container of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Gap part 12 Side wall part 14 Gap part 16 Gap part 22 Thick part 24 Thin part 26 Gap part 28 Bottom part 30 Bottom part 32 Thick part 34 Gap part 40 Die 42 Cavity 54 Cavity 58 Die 60 Cavity 66 Die 70 Low heat Conductivity material

Continuation of the front page (72) Inventor Satoshi Maruyama 2-3-2, Yakko, Kawasaki-ku, Kawasaki-shi, Kanagawa Japan Polyolefin Co., Ltd. Kawasaki Laboratory F-term (reference) 3E067 AA03 AB01 BA07A BB14A CA18 FA01 GA12 4F202 AA03 AE02 AG07 AH52 CA11 CB01 CK19 4F206 AA03 AA11 AE02 AG07 AH52 JA05 JN27 JQ81

Claims (13)

[Claims] 1. A heat insulating container made of synthetic resin, characterized in that a void portion formed upward from a bottom portion integrated with the side wall portion is formed inside the side wall portion. 2. A heat insulating container made of synthetic resin, characterized in that a void portion radially extending from the center of the bottom portion is formed inside the bottom portion. 3. A gap formed radially extending from the center of the bottom inside the bottom, and a gap formed upward in the side wall in communication with the gap inside the bottom. A synthetic resin heat-insulating container characterized in that a heat-insulating container is formed. 4. The method according to claim 1, wherein a thick region and a thin region are formed on a side wall and / or a bottom, and the gap is formed inside the thick region. A heat insulating container made of any one of the above-mentioned synthetic resins. 5. The heat insulating container made of synthetic resin according to claim 1, wherein the gap is formed by a plurality of streaks. 6. The synthetic resin according to claim 4, wherein irregularities caused by the formation of the thick region and the thin region are formed on the inner wall surface, and the outer wall surface of the side wall portion is smooth. Insulated container. 7. The synthetic resin heat insulating container according to claim 1, wherein the heat insulating container is made of a non-foamed material. 8. The synthetic resin heat insulating container according to claim 1, wherein the heat insulating container is made of an olefin resin. 9. The synthetic resin insulation container according to claim 1, wherein the container is formed integrally by gas injection molding. 10. A side wall portion and / or a gas injection molding method.
Alternatively, a method for producing a synthetic resin heat-insulating container, comprising forming a container having a void portion formed inside a bottom portion. 11. The method according to claim 10, wherein a thick region and a thin region are formed on the side wall and / or the bottom. 12. The method according to claim 10, wherein the cavity volume is increased during shaping. 13. The synthetic resin insulation container according to claim 10, wherein a low thermal conductivity material is provided in a portion of the mold corresponding to a void formed in the container to be molded. Method.