JP2007160893A - Molding method and mold of container having taper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold which enables the molding of a tapered container with a uniform thickness of the side face and the thicknesses of the bottom face and the side face can be independently controlled and to provide the molding method. <P>SOLUTION: The molding method of a container having a taper comprises casting/molding a melting resin between a cavity (female mold) and a core (male mold), wherein the core includes a freely movable movement core and a fixed core to be fixed, wherein the movement core includes a plurality of secondary movement cores consisting of one or a plurality of secondary movement cores for molding the taper and one or a plurality of secondary movement cores for molding the bottom face, and wherein the plurality of secondary movement cores are moved respectively, thereby the thickness of the taper and the thickness of the bottom face are molded nearly uniformly. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a container molding method for casting a molten resin between a cavity (female mold) and a core (male mold), and a mold thereof.

2. Description of the Related Art Conventionally, there are known foamable resin containers that have no sink marks or burrs, have a very high foaming ratio, and are excellent in weight reduction. When molding this type of foamable container, there is a disadvantage that a sufficient foaming capacity cannot be ensured by a normal injection molding method. That is, in the injection molding, the gap between the molds becomes the thickness of the container as it is, and when the foamable resin is injection-molded, the resin is once filled into the mold gap and then foamed. There was a drawback that a space required for expansion could not be obtained, resulting in a low-foam molded product.
Therefore, a core back system is used for molding a foamable container, in which a foamable molten resin is poured into a fixed female mold (cavity) and the moving male mold (core) is moved backward to form. It is possible. For example, a container-shaped cavity corresponding to the injection resin volume is formed between molds composed of a fixed mold and a movable mold, and when the resin is filled into the cavity, the movable mold is 1 A container and a method of manufacturing the same are disclosed in which the volume of the cavity is increased and the foaming of the resin proceeds along with the retreat at a speed of ˜5 (mm / sec) (for example, Patent Document 1).
JP 2001-18943 A

  However, when the above-described core back method is applied when molding a container having a taper using an expandable resin, as shown in FIG. Accordingly, when the volume in the cavity is increased, the side surface thickness a is gradually increased a ′, and the bottom surface thickness b is rapidly increased b ′ as shown in FIG. 9B. is there. In particular, as the taper angle θ is smaller, there is a problem that when the side surface thickness a is slightly increased, the bottom surface thickness b is rapidly increased.

  Therefore, in the present invention, when forming a foamable container having a taper, the thickness of the bottom surface is not affected by the increase in the thickness of the taper portion, and it is possible to control to increase only the thickness of the taper portion uniformly. A method and a mold for forming a container having a taper are provided.

  For this reason, the invention according to claim 1 of the present invention is a method for forming a container having a taper in which a molten resin is poured between a cavity (female) and a core (male), and the core is The movable core further includes a movable core that is movable, and a fixed core that is fixed. The movable core further includes a plurality of movable secondary cores, and the taper is formed by moving the secondary movable core. It is the shaping | molding method of the container which has a taper characterized by shape | molding thickness of this.

  The invention according to claim 2 is the method for forming a container having a taper, wherein the plurality of moving cores have different moving amounts or moving speeds.

  The invention according to claim 3 is a method for forming a tapered container, wherein at least one secondary moving core of the plurality of secondary moving cores is a fixed secondary fixed core. .

  According to a fourth aspect of the present invention, there is provided a method for forming a container having a taper, wherein the molten resin is a foamable resin, and the foaming capacity of the foamable resin is varied by moving the moving core. It is.

  The invention according to claim 5 is a method for forming a container having a taper, wherein the taper is a curved surface.

  The invention according to claim 6 is the method for forming a container having a taper, wherein the taper angle is 3 degrees to 10 degrees.

（ただし、θはテーパーの角度、ａは二次移動コアの移動量、ｄは二次移動コアの移動に伴うテーパー部分の厚さの増加量） The invention according to claim 7 is a method for forming a container having a taper, wherein the amount of movement of the secondary moving core, the thickness of the tapered portion, and the angle of the taper are determined by the following equations. .

(Where θ is the taper angle, a is the amount of movement of the secondary moving core, and d is the amount of increase in the thickness of the tapered portion accompanying the movement of the secondary moving core)

  The invention according to claim 8 is a method for forming a container having a taper, which is an in-mold forming method in which a molten resin and a label are simultaneously formed.

  The invention according to claim 9 is a method for forming a container having a taper, wherein in the in-mold forming method, a film having a barrier property is simultaneously formed.

  The invention according to claim 10 is the method for forming a container having a taper, wherein the barrier film is a multilayer coating film.

  The invention according to claim 11 is a mold having a cavity (female mold) and a core (male mold), the mold comprising a movable core movable and a fixed core to be fixed. In the above, the moving core is a mold characterized by comprising a plurality of secondary moving cores that are further movable.

  The invention according to claim 12 is the mold characterized in that the plurality of secondary moving cores have different moving amounts or moving speeds.

  The invention according to claim 13 is the mold, wherein at least one secondary moving core of the plurality of secondary moving cores is a fixed secondary fixed core.

  The invention according to claim 14 is the method for forming a container having a taper and a mold, wherein the tip of the moving core has an acute angle.

  A fifteenth aspect of the present invention is a method and a mold for forming a container having a taper, wherein a part of a tip portion of the moving core is horizontal.

  A sixteenth aspect of the present invention is a container molded by a method or a mold for forming a tapered container according to the first to fifteenth aspects.

  The invention according to claim 17 is the method for forming a tapered container, wherein the container is a cup.

  According to the present invention, there is provided a method for forming a container having a taper for pouring and molding a molten resin between a cavity (female) and a core (male), wherein the core includes a movable core, A fixed core that is fixed, and the moving core further includes a plurality of movable secondary moving cores, and the thickness of the taper is uniformly formed by moving the secondary moving cores. Thus, the thickness of the side surface of the tapered container can be uniformly formed, and the thickness of the bottom surface and the side surface can be controlled independently.

  In addition, since the plurality of moving cores are different in moving amount or moving speed, they can be applied to a container having a complicated shape.

  Since the invention according to claim 3 is characterized in that at least one secondary moving core of the plurality of secondary moving cores is a fixed secondary fixed core, the thickness of the bottom surface (horizontal plane) of the container The foaming capacity of only the tapered portion can be varied while fixing the thickness. That is, the thickness of the bottom surface of the container and the tapered portion can be controlled independently.

  The invention according to claim 4 is characterized in that the molten resin is a foamable resin, and the foaming capacity of the foamable resin is varied by moving the moving core. The thickness of the container side wall can be varied by controlling with the moving core.

  The invention according to claim 5 is characterized in that the taper is a curved surface, so that a container having a curved surface and good design can be formed.

  The invention according to claim 6 is characterized in that the angle of the taper is 3 degrees to 10 degrees, and therefore can be applied to molding general-purpose products such as daily necessities.

（ただし、θはテーパーの角度、ａは二次移動コアの移動量、ｄは二次移動コアの移動に伴うテーパー部分の厚さの増加量） The invention according to claim 7 is characterized in that the amount of movement of the secondary moving core, the thickness of the tapered portion, and the angle of the taper are determined by the following equations. Thus, it is possible to easily calculate results such as the taper angle, the amount of movement of the secondary moving core, and the amount of increase in the thickness of the target tapered portion.

(Where θ is the taper angle, a is the amount of movement of the secondary moving core, and d is the amount of increase in the thickness of the tapered portion accompanying the movement of the secondary moving core)

  Since the invention according to claim 8 is an in-mold molding method in which a molten resin and a label are molded at the same time, there is no need to separately print the container.

  The invention according to claim 9 is characterized in that, in the in-mold molding method, a film having a barrier property is formed at the same time, so that a container having a barrier property (permeation resistance) can be formed.

  The invention according to claim 10 is characterized in that the film having barrier properties is a multilayer coating film, and therefore, a container having not only permeation resistance but also light resistance can be formed.

  The invention according to claim 11 is a mold having a cavity (female mold) and a core (male mold), the mold comprising a movable core movable and a fixed core to be fixed. The moving core is composed of a plurality of secondary moving cores that are further movable, so that the thickness of the side surface of the tapered container can be uniformly formed, and the bottom surface, the side surface, It is possible to provide a mold capable of independently controlling the thickness of the mold.

  The invention according to claim 12 is characterized in that each of the plurality of secondary moving cores has a different moving amount or moving speed. Therefore, even if the container has a complicated shape, the thickness of the side surface of the container having a taper is reduced. It is possible to provide a mold capable of uniformly forming the thickness.

  Since the invention according to claim 13 is characterized in that at least one secondary moving core of the plurality of secondary moving cores is a fixed secondary fixed core, the thickness of the bottom surface (horizontal plane) of the container The foaming capacity of only the tapered portion can be varied while fixing the thickness. That is, it is possible to provide a mold capable of independently controlling the thickness of the bottom surface of the container and the tapered portion.

  The invention according to claim 14 is characterized in that the tip of the moving core has an acute angle, so that the container can be finished without forming a step at the rising portion of the taper.

  The invention according to claim 15 is characterized in that a part of the tip portion of the moving core is horizontal, so that the foaming amount of the tip portion of the moving core can be increased.

  Since the invention described in claim 16 is a method for forming a container having a taper according to claims 1 to 15 or a container formed by a mold, the thickness of the side surface and the bottom surface of the container having a taper by the method and the mold is used. A uniform container can be provided.

  The invention described in claim 17 is applicable to a cup having a taper because the container is a cup.

  As described above, the method and the mold for forming a tapered container according to the present invention can uniformly mold the thickness of the side surface of the container having a taper, and the thickness of the bottom surface regardless of the thickness of the side surface. It can be controlled.

Hereinafter, the metal mold | die of this invention is demonstrated, referring drawings.
FIG. 1 is an example of a mold according to the present invention. The mold 10 includes a cavity 20 (fixed mold) which is a female mold and a core 30 (moving mold) which is a male mold. The core 30 is further connected to the moving core 7. And a fixed core 8. The moving core 7 further includes a plurality of secondary moving cores 7a for forming the side surface 3 (tapered portion) of the container and a secondary moving core 7b for forming the bottom surface 5 of the container. It consists of the next moving core (7a, 7b).
In particular, the tip portion of the secondary moving core 7a forming the taper 3 portion has an acute angle substantially the same as the taper angle θ, while the tip portion of the secondary moving core 7b forming the bottom surface 5 is the bottom surface. 5 is the same horizontal plane.

  And by using such a plurality of secondary moving cores (7a, 7b), the foaming ratio of each part of the container, which will be described later, is independently controlled, and in particular, the container in which the tapered portion and the bottom surface have a uniform foaming ratio. Can be molded. That is, while eliminating the conventional problem that the thickness of the bottom surface 5 is affected by the increase in the thickness a of the tapered portion 3, even if the container has a complicated shape, Each part can be molded with a desired expansion ratio.

A method for forming a tapered container with the mold 10 will be described. Hereinafter, the amount of movement of the secondary moving core 7a that forms the tapered portion is denoted by Δd, and the amount of movement of the secondary moving core 7b that forms the bottom surface is denoted by Δb.
First, foamable molten resin B is injected into a gap (inside the cavity) between the core 30 and the cavity 20 from an injection port (not shown). The inside of the cavity has a reference taper thickness and a bottom thickness in advance, and after injecting the molten resin B, the secondary moving core (7a, 7b) is moved vertically.
At this time, as the secondary moving cores 7a and 7b move in the vertical direction, the thickness of the taper portion and the bottom surface gradually increases. Different. That is, due to the movement of the secondary moving core, the rate of increase in the thickness of the tapered portion is low, while the thickness of the bottom surface is the amount of movement of the secondary moving core itself, and thus the rate of increase is high.
Specifically, the relationship between the amount of increase Δa of the taper portion relative to the amount of movement Δd of the secondary moving core 7a is given by the following equation 1.

That is, the amount of increase Δa in the taper portion accompanying the movement of the secondary moving core 7a in the taper portion depends on the taper angle θ. The smaller the taper angle, the smaller the amount of increase in the thickness of the taper portion. The amount of movement of the secondary moving core 7a is required.
Further, conventionally, when a container having a taper is formed, the taper portion and the bottom surface are simultaneously formed by one moving core. In this case, as described above, in the range where the taper angle is as small as 1 to 30 degrees, the value of sin θ is very small as sin θ = 0.01 to 0.5. Along with the slight increase Δa of the taper portion, the secondary moving core has a large movement amount Δd, so the thickness of the bottom surface suddenly increases from 2 times to 100 times the increase amount Δa of the taper portion. There is a problem.

For this reason, in this invention, while forming a taper part and a bottom face with a some secondary movement core, respectively, the movement amount of the secondary movement core (7a) which shape | molds a taper part, and a bottom face are shape | molded. By making the amount of movement of the secondary moving core (7b) different from each other, parts where the amount of increase in the capacity in the cavity in each part of the container, which occurs when the container is molded, are separately molded, and foaming at each part The magnification can be controlled.
Further, for various containers having different taper angles θ, the increase amount Δa of the taper portion thickness based on the value of sin θ of the taper portion and the movement amount Δd of the secondary moving core is shown in Table 1 below. Can be shown. Therefore, based on Table 1, the thickness of the target tapered portion can be controlled, and the thickness of the bottom surface can be separately controlled.
Furthermore, as shown in Table 2, a container having a desired taper portion thickness and a foaming ratio can be formed on the basis of the thickness of the initial taper portion in the cavity. In this manner, the tapered container 1 having the taper portion 3 and the bottom surface 5 having a substantially uniform thickness W as shown in FIG. 2 can be formed.

  Hereinafter, an example of a method for forming a container having a taper with various angles θ will be described with reference to examples. Here, the initial values of the thickness a of the tapered portion in the cavity and the thickness b of the bottom surface at the time of injection of the molten resin are respectively applied to the following examples with a = b = 1 mm.

Example 1
When the taper angle θ of the target container is 4 degrees, when the foaming ratio of the foamable resin in the tapered portion is 70%, and the thickness of the bottom surface of the container is also 70%, the target after foaming The taper portion has a thickness of 1.7 mm and a bottom surface thickness of 1.7 mm.
Therefore, since the respective increments are Δa = 0.7 mm and Δb = 0.7 mm, from Table 1 (Δa = 0.698 mm), the necessary moving amount of the secondary moving core 7a of the tapered portion is It can be seen that Δd = 10 mm.
Further, since the bottom surface of the container is horizontal, the distance that the secondary moving core 7b is moved vertically becomes the increment Δb of the thickness of the bottom surface as it is, so that the moving amount of the secondary moving core 7b is Δb = 0. By setting the thickness to 7 mm, it is possible to form a target container having a taper portion thickness a + Δa = 1.7 mm and a bottom surface thickness b + Δb = 1.7 mm as shown in FIG.

Example 2
When the taper angle θ of the container is 6 degrees, the expansion ratio of the foamable resin of the target tapered portion is 100 percent (2 times), and the bottom surface of the container is 200 percent (3 times). The thickness of the tapered portion after foaming is 2 mm, and the thickness of the bottom surface is 3 mm.
Therefore, since the respective increments are Δa = 1 mm and Δb = 2 mm, from Table 1, Δd = 10 mm when Δa = 1.445 (≈1 mm). Therefore, it can be seen that the required moving amount of the secondary moving core 7a at the tapered portion is Δd = 10 mm.
Further, the amount of movement of the secondary moving core 7b forming the bottom surface of the container is set to Δb = 2 mm, so that the desired thickness a + Δa = after the foaming as shown in FIG. A container having a thickness of 2 mm and a bottom surface thickness b + Δb = 3 mm can be formed.

Example 3
When the taper angle θ of the container is 13 degrees, the foaming ratio of the foamable resin of the target taper portion is 200 percent (3 times), and the bottom surface of the container is 100 percent (2 times). The thickness of the tapered portion after foaming is 3 mm, and the thickness of the bottom surface is 2 mm.
Therefore, since the respective increments are Δa = 2 mm and Δb = 1 mm, from Table 1, the taper angle θ is 13 degrees, and the movement amount of the secondary moving core 7a in the tapered portion is Δa = 2.525 (≈ 2 mm), Δd = 9 mm. Therefore, it can be seen that the necessary movement amount Δd of the secondary moving core 7a is 9 mm.
Further, by setting the amount of movement of the secondary moving core 7b for forming the bottom surface of the container to Δb = 1 mm, the thickness of the tapered portion after foaming, as shown in FIG. 5B, a + Δa = 3 mm A container having a bottom surface thickness b + Δb = 2 mm can be formed.

  In this way, it is possible to easily mold the container by independently controlling the thickness and the foaming ratio of the tapered portion and the bottom surface.

Further, the plurality of secondary moving cores may be secondary moving cores each having a different moving amount or moving speed, and particularly when the moving amount or moving speed is zero, it is called a secondary fixed core. is there. And a taper part is shape | molded by a secondary moving core, and a bottom face is shape | molded by a secondary fixed core, Therefore The container which makes only a taper part high foaming and a bottom face part low foaming can be shape | molded easily.
Further, in a container having a plurality of stages of taper angles and a container having a tapered surface having a complicated curved surface (curved surface) as shown in Example 4 and Example 5 below, a plurality of secondary moving cores are used. By forming each tapered portion, it is possible to easily vary the thickness and the foaming ratio for each taper.

Example 4
When the taper angle θ of the container has two steps of θ ₁ = 6 degrees and θ ₂ = 13 degrees, the foaming ratio of each tapered portion is 100 percent (2 times), and the thickness of the bottom surface of the container is also Similarly, when the expansion ratio is 100%, the thicknesses of the respective tapered portions and the bottom surface after the target foaming are 2 mm.
Therefore, the increments in each part are Δa (6 °) = 1 mm, Δa (13 °) = 1 mm, and Δb = 1 mm. From Table 1, the taper angle θ is 6 degrees, and the secondary moving core of the taper portion. The movement amount of 7a is Δd (6 °) = 10 mm when Δa (6 °) = 1.45 (≈1 mm), and the taper angle θ is 13 degrees, and the secondary moving core 7b in the tapered portion When Δa (13 °) = 0.900 (≈1 mm), Δd (13 °) = 4 mm. Therefore, it can be seen that the necessary movement amount Δd (6 °) of the secondary moving core 7a = 10 mm and the movement amount Δd (13 °) of the secondary moving core 7b = 4 mm.
Further, by setting the amount of movement of the secondary moving core that forms the bottom surface of the container to Δb = 1 mm, the thickness of each tapered portion after foaming as shown in FIG. A container having a thickness of 2 mm and a bottom surface thickness b + Δb = 2 mm can be formed.

Example 5
As shown in FIG. 7, when a container having a tapered surface having a curved surface and molding only a taper thickness with an expansion ratio of 20%, the curved surface is formed of a plurality of secondary moving cores (7a, 7b, 7c, 7d, and 7e) and the portion where the taper angle θ is large reduces the amount of movement of the secondary moving core (7b, 7d), and the portion where the taper angle θ is small is the secondary moving core (7a, 7c). By increasing the amount of movement, it is possible to form the curved surface smoothly and uniformly as shown in FIG.

  Also, as shown in FIG. 8, in order to strengthen the portion where the side surface (tapered portion) and the bottom surface are in contact with each other, when it is desired to form the portion thickly, the width Δm is set to a part of the tip portion of the secondary moving core 7a. By providing this, as shown in FIG. 8B, it is possible to obtain a further foaming capacity by multiplying the width Δm of the tip portion by the movement amount Δd of the secondary moving core. Therefore, it is possible to thicken relatively weak parts such as the part where the side and bottom face contact each other and the part where the taper part of multiple steps contacts, and the strength of the mold at the tip of the moving core is also increased and durable. The effect is also improved.

  Further, an in-mold molding method in which printing is performed simultaneously with injection molding may be applied to the present invention. In this case, it is possible to provide a container having a barrier property by imparting a barrier property to the label or by simultaneously performing in-mold molding of a printed label and a barrier film. Therefore, it is possible to improve not only the design property but also the permeation resistance.

  Examples of the container include beverage cups, instant food containers, and daily necessities. In particular, when used as a container for pouring hot water or the like, it is desirable to mold the side surface of the container with a high expansion ratio.

  In particular, the vertical heat insulating container has conventionally been difficult to form a container with a foamed bead molding cup or a finned injection cup combined with a shrink label. However, it is possible to mold a lightweight cup with high design and high heat insulation.

As the above-mentioned foaming resin, a foaming agent is blended in advance in a polypropylene resin or the like, or a foaming agent is injected from the middle of the cylinder. Thus, a polypropylene resin containing a foaming agent has a resin temperature of 170 to The pressure is adjusted to about 270 ° C., the injection pressure is 10 to 200 MPa, and the injection time is about 5 seconds. In particular, when the resin temperature, injection pressure, and injection time are within the above-mentioned conditions, a molded product having a high expansion ratio and good appearance can be obtained.
Moreover, it is desirable to move the secondary moving core at a speed of 1 to 10 (mm / sec) at the same time as the injection of the molten resin is completed. At this time, the foamed resin expands and is cooled and cooled while changing to the shape of the cavity.

The foaming agent may be either a solvent-type foaming agent or a decomposable foaming agent. The solvent-type foaming agent is injected from a cylinder portion of an injection molding gas and absorbed or dissolved in a molten polypropylene resin, and then injected. It is a substance that evaporates in the mold and functions as a foaming agent, and low-boiling point aliphatic hydrocarbons such as propane, butane, neopentane, isohexane, hexane, heptane, and low-boiling point fluorine-containing hydrocarbons are used. .
The decomposable foaming agent is pre-blended with polypropylene resin and supplied to an injection molding machine, and the foaming agent decomposes under the cylinder temperature conditions of the injection molding machine, generating expectations for carbon dioxide gas, nitrogen gas, etc. The compound may be an inorganic foaming agent or an organic foaming agent, and an organic acid that promotes gas generation may be added in combination. Specific examples of the decomposable foaming agent include the following compounds.
(A) Inorganic foaming agent: sodium bicarbonate, sodium carbonate, ammonium bicarbonate, ammonium carbonate, ammonium nitrite.
(B) Organic foaming agent: N-nitroso compounds such as N, N′-dinitrosoterephthalamide, N, N′-dinitrosopentamethylenetetramine; azodicarbonamide, azobisisobutyronitrile, azocyclohexylnitrile, Azo compounds such as azodiaminobenzene and barium azodicarboxylate; sulfonyl hydrazides such as benzenesulfonyl hydrazide, toluenesulfonyl hydrazide, p, p'-oxybis (benzenesulfenyl hydrazide), diphenylsulfon-3,3'-disulfonyl hydrazide Compound: Azide compounds such as calcium azide, 4,4′-diphenyldisulfonyl azide, p-toluenesulfonyl azide and the like.

  These foaming agents may be used alone or in combination of two or more. The addition amount of the foaming agent is determined in consideration of the amount of gas generated from the foaming agent, a desirable foaming ratio, etc. so as to match the physical properties of the container described above, but generally 0.1 to 6 weights with respect to 100 parts by weight of polypropylene. A range of parts is preferred. Within this range, a foam container having a uniform cell diameter can be obtained. As a specific example of the foamed material, there is a trade name “Selfon” whose main component is sodium hydrogen carbonate (bicarbonate), manufactured by Eiwa Kasei Co., Ltd., which is the same as FE-507, Selfbon SC-855, and Selfbon SC-P. In particular, when a container having various grades such as SC-K, SC-850, and SC-540 and having a high foaming rate is molded, it is desirable to use Cellbon SC-P.

Moreover, the film having the barrier property is not particularly limited as long as it does not transmit a gas such as oxygen. Examples of the material of the film include aluminum, carbon, silica, and a multilayer film such as EVOH. By using it, it is possible to improve not only the transmission resistance but also the light blocking resistance.

It is a cross-sectional top view which shows the metal mold | die of this invention. It is explanatory drawing which shows the shaping | molding method of the container which has a taper of this invention. It is explanatory drawing which shows an example of the shaping | molding method of the container which has a taper of this invention. It is explanatory drawing which shows an example of the shaping | molding method of the container which has a taper of this invention. It is explanatory drawing which shows an example of the shaping | molding method of the container which has a taper of this invention. It is explanatory drawing which shows an example of the shaping | molding method of the container which has a taper of this invention. It is explanatory drawing which shows an example of the shaping | molding method of the container which has a taper of this invention. It is explanatory drawing which shows an example of the shaping | molding method of the container which has a taper of this invention. It is explanatory drawing which shows an example of the shaping | molding method of the container which has the conventional taper.

Explanation of symbols

1 Container 3 Side (tapered part)
5 Bottom surface 7 Moving core 7a, 7b, 7c, 7d, 7e Secondary moving core 8 Fixed core 10 Mold 20 Cavity 30 Core

Claims (17)

A method for forming a container having a taper for pouring and molding molten resin between a cavity and a core, wherein the core includes a movable core that is movable and a fixed core that is fixed. And a plurality of secondary moving cores including one or more secondary moving cores for forming the taper and one or more secondary moving cores for forming the bottom surface. A method for forming a container having a taper, wherein the thickness of the taper and the thickness of the bottom surface are formed substantially uniformly by moving each of the moving cores. The method for forming a container having a taper according to claim 1, wherein the moving cores have different moving amounts or moving speeds. 3. The method for forming a container having a taper according to claim 1, wherein at least one secondary moving core of the plurality of secondary moving cores is a fixed secondary fixed core. 4. The method for forming a tapered container according to claim 1, wherein the molten resin is a foamable resin, and the foaming capacity of the foamable resin is varied by moving the moving core. 5. The method for forming a container having a taper according to claim 1, wherein the taper is a curved surface. 6. The method for forming a container having a taper according to claim 1, wherein an angle of the taper is 3 degrees to 10 degrees. The method for forming a container having a taper according to any one of claims 1 to 6, wherein the movement amount of the secondary moving core, the thickness of the taper portion, and the taper angle are determined by the following equations.

(Where θ is the taper angle, a is the amount of movement of the secondary moving core, and d is the amount of increase in the thickness of the tapered portion accompanying the movement of the secondary moving core) 8. The method for forming a container having a taper according to claim 1, wherein the method is an in-mold molding method in which a molten resin and a label are molded simultaneously. 9. The method for forming a container having a taper according to claim 8, wherein a film having a barrier property is simultaneously formed in the in-mold forming method. The method for forming a tapered container according to claim 9, wherein the film having a barrier property is a multilayer coating film. A mold having a cavity and a core, wherein the core is a mold including a movable core that is movable and a fixed core that is fixed, and the movable core is further movable in a plurality of secondary movements. A mold characterized by comprising a core. The mold according to claim 11, wherein the plurality of secondary moving cores have different moving amounts or moving speeds. The mold according to claim 11, wherein at least one secondary moving core of the plurality of secondary moving cores is a fixed secondary fixed core. 14. The method for forming a tapered container and a mold according to claim 1, wherein the tip of the moving core has an acute angle. The method for forming a container having a taper and a mold according to claim 1, wherein a part of a tip portion of the moving core is horizontal. 16. A method for forming a tapered container according to claim 1 or a container formed by a mold. The method for forming a tapered container according to claim 16, wherein the container is a cup.

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