Preform, composite preform, container body and composite container

Abstract

To produce a container of a desired shape by stretching a heated preform.SOLUTION: The preform 10a comprises a mouth 11a and a trunk 20a connected to the mouth 11a. A rough surface 20c is formed on a part of a surface 20b of the trunk 20a, which is rougher than the other part of the surface 20b of the trunk 20a.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a preform, a composite preform, a container body, and a composite container. [Background technology]

[0002] Recently, containers for holding liquid contents such as food and drink have become common, such as those made of plastic as shown in Patent Document 1. Such plastic containers hold liquid contents.

[0003] Such a container for containing a liquid content is manufactured by inserting a preform into a mold and subjecting it to biaxial stretch blow molding. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2015-128858 A Summary of the Invention [Problem to be solved by the invention]

[0005] In biaxial stretch blow molding, a container is produced by stretching a heated preform using a heating device. In this case, it is required to stably produce a container of a desired shape by stretching the heated preform. In particular, it is required to stably produce a container of a desired shape even when the heating device has a low output.

[0006] The present invention has been made in consideration of these points, and has as its object to produce a container of a desired shape by stretching a heated preform. [Means for solving the problem]

[0007] A first aspect of the present disclosure is a preform comprising a mouth portion and a body portion connected to the mouth portion, wherein a portion of a surface of the body portion is formed with a rough surface that is rougher than other portions of the surface of the body portion.

[0008] A second aspect of the present disclosure is the preform according to the first aspect described above, wherein the rough surface has an arithmetic mean roughness Ra of 0.05 or more and 1.00 or less.

[0009] A third aspect of the present disclosure is a preform according to the first aspect or the second aspect described above, wherein the body portion has a neck portion connected to the mouth portion and a middle portion connected to the neck portion, and the rough surface may be formed on the neck portion.

[0010] A fourth aspect of the present disclosure is a preform according to each of the first aspect to the third aspect described above, wherein the preform further comprises a bottom portion connected to the body portion, and the arithmetic mean roughness Ra of the surface of the bottom portion may be less than 0.05.

[0011] A fifth aspect of the present disclosure is a composite preform comprising a preform according to any one of the first to fourth aspects described above and a plastic member provided on the outside of the preform.

[0012] A sixth aspect of the present disclosure is a container body comprising a mouth, a body connected to the mouth, and a bottom connected to the body, wherein the body has a neck connected to the mouth, a shoulder connected to the neck, and a middle body connected to the shoulder, and when a portion of the neck and shoulder that is 24.00 mm or more away from the boundary between the mouth and the neck is defined as a first portion, the thickness of the first portion is 1.2 times or less the thickness of the middle body.

[0013] A seventh aspect of the present disclosure is a container body according to the sixth aspect described above, wherein a part of the surface of the body portion is formed with a rough surface that is rougher than other parts of the surface of the body portion.

[0014] An eighth aspect of the present disclosure is a container body according to the sixth aspect or the seventh aspect described above, wherein the rough surface may be formed on at least one of the neck portion and the shoulder portion.

[0015] A ninth aspect of the present disclosure is that, in a container body according to each of the sixth to eighth aspects described above, when a portion of the neck and shoulder that is 15 mm or more and 25 mm or less away from the boundary is defined as a second portion, and a portion that is 25 mm or more and 35 mm or less away from the boundary is defined as a third portion, the mass of the second portion may be less than or equal to twice the mass of the third portion.

[0016] A tenth aspect of the present disclosure is a composite container comprising a container body according to any one of the sixth to ninth aspects described above, and a plastic member provided on the outside of the container body. Effect of the Invention

[0017] According to the present disclosure, a container of a desired shape can be produced by stretching a heated preform. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a partial vertical cross-sectional view showing a container body according to one embodiment. [Figure 2A] FIG. 2A is a horizontal cross-sectional view (a cross-sectional view taken along line IIA-IIA in FIG. 1) showing a container body according to one embodiment. [Figure 2B] FIG. 2B is a partial vertical cross-sectional view showing the vicinity of the shoulder and neck of the container body according to one embodiment. [Diagram 3] FIG. 3 is a partial vertical cross-sectional view showing a preform according to one embodiment. [Figure 4] FIG. 4 is a horizontal cross-sectional view (a cross-sectional view taken along line IV-IV in FIG. 3) showing a preform according to one embodiment. [Diagram 5] FIG. 5 is a partial vertical cross-sectional view showing the vicinity of a neck portion of a preform according to one embodiment. [Figure 6] 6(a) to (e) are schematic diagrams showing a method for manufacturing a container body according to one embodiment. [Figure 7] FIG. 7 is a partial vertical sectional view showing a container body according to the first modified example. [Figure 8] FIG. 8 is a partial vertical sectional view showing a preform according to a first modified example. [Figure 9] FIG. 9 is a partial vertical sectional view showing a composite container according to a second modified example. [Figure 10] FIG. 10 is a partial vertical sectional view showing a composite preform according to a second modified example. [Figure 11] 11(a) to 11(d) are perspective views showing various plastic members. [Figure 12] 12(a) and 12(b) are schematic diagrams showing a manufacturing method for a composite container according to Modification 2. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] An embodiment will be described below with reference to the drawings. FIGS. 1 to 6 are diagrams showing an embodiment. Each of the figures shown below is a schematic diagram. Therefore, the size and shape of each part are appropriately exaggerated to facilitate understanding. In addition, the present invention can be modified appropriately within the scope of the technical concept. In each of the figures shown below, the same parts are given the same reference numerals, and some detailed explanations may be omitted. In addition, the numerical values ​​such as the dimensions of each member and the material names described in this specification are examples of an embodiment, and are not limited to these, and can be selected and used appropriately. In this specification, terms that specify shapes and geometric conditions, such as parallel, orthogonal, and vertical, include substantially the same state in addition to their strict meanings.

[0020] Container body configuration First, an overview of the container body according to the present embodiment will be described with reference to Figures 1 to 2B. In this specification, "upper" and "lower" refer to the upper and lower sides of the container body when it is held upright (Figure 1). In this specification, "vertical direction" refers to the upper and lower sides of the container body when it is held upright (Figure 1).

[0021] The container body 10 shown in Figs. 1 to 2B is a container obtained by subjecting a preform 10a (see Figs. 3 and 4) to biaxial stretch blow molding, as will be described later.

[0022] The container body 10 includes a mouth 11, a body 20 connected to the mouth 11, and a bottom 30 connected to the body 20. The body 20 is provided below the mouth 11. The bottom 30 is provided below the body 20. The container body 10 is made of, for example, a plastic material.

[0023] The mouth portion 11 has a threaded portion 14 that is screwed onto a cap (not shown), and a flange portion 17 provided below the threaded portion 14. A neck portion 13 of the body portion 20, which will be described later, is connected to the flange portion 17 of the mouth portion 11. Therefore, a boundary 25 between the mouth portion 11 and the neck portion 13 is formed at the lower end portion in the vertical direction of the flange portion 17. The shape of the mouth portion 11 may be a conventionally known shape. The container body 10 is filled with contents such as a content liquid, and a cap (not shown) is screwed onto the mouth portion 11 to produce a container containing the contents.

[0024] The body portion 20 has a neck portion 13 connected to the mouth portion 11 , a shoulder portion 12 connected to the neck portion 13 , and a middle body portion 23 connected to the shoulder portion 12 .

[0025] The neck portion 13 is provided below the mouth portion 11. The neck portion 13 is located between the flange portion 17 and the shoulder portion 12. The neck portion 13 has a generally cylindrical shape with a generally uniform diameter.

[0026] The shoulder 12 is provided below the neck 13. The shoulder 12 is located between the neck 13 and a middle part 23 of the body 20, which will be described later. The shoulder 12 has a shape in which the diameter gradually increases from the neck 13 side toward the middle part 23 side (a shape in which the area gradually increases in a horizontal cross section). In this embodiment, the distance (vertical distance) w2 from the boundary 25 between the mouth 11 and the neck 13 of the container body 10 to the lower end of the shoulder 12 may be 35 mm or more. In other words, the distance w2 in the vertical direction between the boundary 25 between the mouth 11 and the neck 13 of the container body 10 and the boundary 28 between the shoulder 12 and the middle part 23 may be 35 mm or more.

[0027] The central trunk portion 23 is provided below the shoulder portion 12. The central trunk portion 23 has a cylindrical shape with a generally uniform diameter overall. However, the shape of the central trunk portion 23 is not limited to this. The central trunk portion 23 may have a polygonal cylindrical shape such as a rectangular cylindrical shape or an octagonal cylindrical shape. The central trunk portion 23 may have a cylindrical shape with a non-uniform horizontal cross section from top to bottom. The outer surface of the central trunk portion 23 may have unevenness such as a vacuum absorption panel or a groove.

[0028] In the container body 10, the angle that the surface 20d makes with respect to the up-down direction changes between the neck portion 13 and the shoulder portion 12, and between the shoulder portion 12 and the middle body portion .

[0029] In Fig. 1, the bottom 30 has a recess 31 located in the center and a grounding portion 32 provided around the recess 31. The shape of the bottom 30 is not limited to the shape shown in Fig. 1. The bottom 30 may have a conventionally known bottom shape (for example, a petaloid bottom shape, a rounded bottom shape, etc.).

[0030] Next, the body 20 of the container body 10 according to this embodiment will be described in detail with reference to Figs. 1 and 2B.

[0031] 1 and 2B, in the container body 10, a part of the surface 20d of the body 20 is formed with a rough surface 20e (shaded part in FIG. 1) that is rougher than the other parts of the surface 20d of the body 20. In the container body 10 shown in FIG. 1, the rough surface 20e is formed over the entire neck 13 and shoulder 12. The surface 20d of the bottom 30 does not have any part that is rougher than the part of the surface 20d of the body 20 where the rough surface 20e is not formed (see FIG. 1).

[0032] The degree of roughness of the surface 20d and the rough surface 20e is determined by the arithmetic mean roughness Ra. The arithmetic mean roughness Ra is measured using a surface roughness measuring instrument (product name "SURFCOM1400G", manufactured by Tokyo Seimitsu Co., Ltd.) in accordance with JIS B0601:2013.

[0033] As shown in Fig. 2B, in this embodiment, the portion of the neck portion 13 and shoulder portion 12 of the container body 10 that is 24.00 mm or more away from the boundary 25 between the mouth portion 11 and the neck portion 13 is defined as the first portion 24. In other words, the distance w1 between the upper end of the first portion 24 shown in Fig. 2B and the boundary 25 is 24.00 mm.

[0034] Of the neck 13 and shoulder 12 of the container body 10, the portion that is 15 mm or more and 25 mm or less away from the boundary 25 is defined as a second portion 26. Of the neck 13 and shoulder 12 of the container body 10, the portion that is 25 mm or more and 35 mm or less away from the boundary 25 is defined as a third portion 27 of the container body 10. Of the neck 13 and shoulder 12 of the container body 10, the portion that is 15 mm or less away from the boundary 25 is defined as a fourth portion 29.

[0035] In summary, the first portion 24, the second portion 26, the third portion 27, and the fourth portion 29 may be as shown in Table 1 below.

[0036] [Table 1]

[0037] In this embodiment, the thickness t3 of the first portion 24 is 1.2 times or less the thickness t1 of the middle trunk portion 23. In the container body 10 in which the thickness t3 of the first portion 24 is 1.2 times or less the thickness t1 of the middle trunk portion 23, it is considered that the size of the meat reservoir 19 described below is kept sufficiently small. The container body 10 having such characteristics can be manufactured from a preform 10a on which a rough surface 20c described below is formed.

[0038] The mass of the second portion 26 may be equal to or less than twice the mass of the third portion 27. In the container body 10 in which the mass of the second portion 26 is equal to or less than twice the mass of the third portion 27, the size of the meat reservoir 19 formed in the second portion 26, which will be described later, is considered to be sufficiently small.

[0039] 2B, in this embodiment, a portion having a thickness t2 larger than the thickness t1 of the middle body portion 23 is formed in the entire neck portion 13 of the container body 10 and in a part of the upper part of the shoulder portion 12. The portion thicker than the middle body portion 23 of the container body 10, which is formed in at least one of the shoulder portion 12 and the neck portion 13 of the container body 10, is called a meat reservoir 19. In this embodiment, the meat reservoir 19 is formed in the entire fourth portion 29 and a part of the second portion 26 of the neck portion 13 and the shoulder portion 12.

[0040] The meat reservoir 19 includes a thick region 18, which is a region whose thickness is greater than 1.2 times the thickness t1 of the middle body portion 23. In FIG. 2B, the thick region 18 is formed in the upper part of the meat reservoir 19. Specifically, the thick region 18 is formed in the entire neck portion 13 of the container body 10 and in a part of the upper part of the shoulder portion 12. The distance w5 from the boundary 25 to the lower end of the thick region 18 is less than 24.00 mm. Even when the thick region 18 is formed as in FIG. 2B, the thickness t3 of the first portion 24 can be made 1.2 times or less the thickness t1 of the middle body portion 23 as long as the distance w5 is less than 24.00 mm.

[0041] The thickness of the container body 10 is not particularly limited. The thickness of the container body 10 at the middle body portion 23 is, for example, 50 μm or more and 250 μm or less. The weight of the container body 10 is not particularly limited. The weight of the container body 10 is, for example, 10 g or more and 20 g or less. By reducing the thickness of the container body 10, the weight of the container body 10 can be reduced.

[0042] The container body 10 can be produced by biaxially stretching and blow molding a preform 10a (described later) produced by injection molding a synthetic resin material. The material of the container body 10 is preferably a thermoplastic resin, particularly PE (polyethylene), PP (polypropylene), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), or PC (polycarbonate). The container body 10 may be colored in colors such as red, blue, yellow, green, brown, black, and white, but is preferably colorless and transparent in consideration of ease of recycling. The above-mentioned various resins may be blended and used. A vapor deposition film may be formed on the inner surface of the container body 10 to improve the barrier properties of the container. The vapor deposition film is, for example, a vapor deposition film such as a diamond-like carbon film or a silicon oxide thin film.

[0043] The container body 10 may be formed as a multi-layered bottle having two or more layers. That is, the container body 10 may be formed by the following method. First, a preform 10a having three or more layers is molded by injection molding. The intermediate layer of the preform 10a having three or more layers is, for example, a layer of a resin having gas barrier properties. The resin having gas barrier properties is, for example, MXD6, MXD6 + fatty acid salt, PGA (polyglycolic acid), EVOH (ethylene vinyl alcohol copolymer), PEN (polyethylene naphthalate), or the like. Then, the preform 10a is blow molded. This forms a multi-layered bottle having gas barrier properties. The intermediate layer may be a resin obtained by blending the above-mentioned various resins.

[0044] The container body 10 may be produced by the following method. First, a foamed preform is molded by mixing an inert gas (nitrogen gas, argon gas) with a melt of a thermoplastic resin. The molded foamed preform has a foam cell diameter of 0.5 μm or more and 100 μm or less. The container body 10 is produced by blow molding this foamed preform. Since such a container body 10 has foam cells built in, the light blocking property of the entire container body 10 can be improved.

[0045] The container body 10 may be a bottle having a full capacity of, for example, 100 ml to 2000 ml, or a large bottle having a full capacity of, for example, 10 L to 60 L.

[0046] Preform Composition Next, the configuration of the preform 10a will be described with reference to FIGS.

[0047] The preform 10a includes a mouth portion 11a and a body portion 20a connected to the mouth portion 11a. The preform 10a further includes a bottom portion 30a connected to the body portion 20a. The mouth portion 11a of the preform 10a corresponds to the mouth portion 11 of the container body 10 described above. The mouth portion 11a has approximately the same shape as the mouth portion 11. The body portion 20a of the preform 10a corresponds to the body portion 20 of the container body 10 described above. The body portion 20a has an approximately cylindrical shape. The bottom portion 30a of the preform 10a corresponds to the bottom portion 30 of the container body 10 described above. The bottom portion 30a has an approximately hemispherical shape.

[0048] 3, the body 20a has a neck 21 connected to the mouth 11a and a middle body 22 connected to the neck 21. Of these, the neck 21 corresponds to the neck 13 and shoulder 12 of the body 20 of the container body 10 described above. The middle body 22 corresponds to the middle body 23 of the body 20 of the container body 10 described above.

[0049] As shown in Fig. 5, the neck portion 21 has a cylindrical portion 21a connected to the mouth portion 11a and a reduced diameter portion 21b connected to the cylindrical portion 21a. Fig. 5 shows the details of the shape of the neck portion 21 that were omitted in Fig. 3. Fig. 5 does not show a rough surface 20c, which will be described later.

[0050] The cylindrical portion 21a of the neck 21 has a cylindrical shape with a constant diameter w6. The reduced diameter portion 21b has a shape in which the diameter w7 gradually decreases from the mouth 11a side toward the bottom 30a side (a shape in which the area gradually decreases in horizontal cross section).

[0051] The central trunk portion 22 has a cylindrical shape with a generally uniform diameter as a whole. As shown in Fig. 5, the diameter w4 of the central trunk portion 22 is smaller than the diameter w6 of the cylindrical portion 21a and the diameter w7 of the reduced diameter portion 21b.

[0052] 3, a part of the surface 20b of the body 20a is formed with a rough surface 20c (shaded area in FIG. 3) that is rougher than the other part of the surface 20b of the body 20a. In FIG. 3, the rough surface 20c is formed in the neck 21. In particular, the rough surface 20c is formed over the entire neck 21. As an example, the rough surface 20c formed in the neck 21 is rougher than the surface 20b in the middle body portion 22.

[0053] The degree of roughness of the surface 20b and the rough surface 20c is determined by the arithmetic mean roughness Ra. The rough surface 20c is rougher than the other portions of the surface 20b of the body 20a where the rough surface 20c is not formed, meaning that the arithmetic mean roughness Ra of the rough surface 20c is larger than the arithmetic mean roughness Ra of the other portions where the rough surface 20c is not formed. The rough surface 20c formed in the neck 21 is rougher than the surface 20b in the middle body 22, meaning that the arithmetic mean roughness Ra of the rough surface 20c formed in the neck 21 is larger than the arithmetic mean roughness Ra of the surface 20b in the middle body 22.

[0054] As an example, the arithmetic mean roughness Ra of the rough surface 20c is not less than 0.05 and not more than 1.00.

[0055] In FIG. 3, the surface 20b of the bottom 30a of the preform 10a does not have a rougher portion than the portion of the surface 20b of the body 20a where the rough surface 20c is not formed. In this case, the arithmetic mean roughness Ra of the surface 20b of the bottom 30a is, for example, less than 0.05. This makes the portion of the surface 20b of the body 20a of the preform 10a where the rough surface 20c is formed more easily by heating. It is clear from the results of the examples described later that by not forming a rougher portion than the portion of the surface 20b of the body 20a where the rough surface 20c is not formed on the surface 20b of the bottom 30a of the preform 10a, the portion of the surface 20b of the body 20a where the rough surface 20c is formed is more easily stretched.

[0056] When the container body 10 is manufactured from the preform 10a on which the rough surface 20c is formed, a trace of the rough surface 20c of the preform 10a may remain on the container body 10. In this case, the above-mentioned rough surface 20e is formed on a part of the surface 20d of the body 20 of the manufactured container body 10. The rough surface 20e of the container body 10 is formed on at least a part of a portion corresponding to the portion where the rough surface 20c was formed in the preform 10a. In the preform 10a shown in FIG. 3, the rough surface 20c is formed on the neck portion 21. The neck portion 21 of the body portion 20a of the preform 10a corresponds to the neck portion 13 and shoulder portion 12 of the body portion 20 of the container body 10 described above. Therefore, in the container body 10 manufactured from the preform 10a shown in FIG. 3, the rough surface 20e can be formed on at least one of the neck portion 13 or the shoulder portion 12.

[0057] Method for manufacturing preform and container body Next, a manufacturing method (blow molding method) for the container body 10 according to this embodiment will be described with reference to Figs. 6(a) to (e).

[0058] First, a preform 10a is prepared in which a rough surface 20c is formed on a part of a surface 20b of a body portion 20a (see FIG. 6(a)). In this case, the preform 10a may be produced by an injection molding method using an injection molding machine (not shown). A preform that is generally used in the past may be used as the preform 10a.

[0059] The method of forming the rough surface 20c on a part of the surface 20b of the body 20a is not particularly limited. When the preform 10a is produced using an injection molding machine, a surface having a shape corresponding to the rough surface 20c may be formed at a position of the mold of the injection molding machine corresponding to a part of the surface 20b of the body 20a. By using an injection molding machine having a mold on which a surface having a shape corresponding to the rough surface 20c is formed, the preform 10a on which the rough surface 20c is formed can be produced by an injection molding method. In this case, a surface having a shape corresponding to the rough surface 20c can be formed by performing a blasting process at a position of the mold of the injection molding machine corresponding to a part of the surface 20b of the body 20a. After preparing a preform that is generally used in the past and does not have the rough surface 20c formed on the surface 20b, the rough surface 20c may be formed on a part of the surface 20b of the body 20a of the preform. In this case, the rough surface 20c may be formed by sanding a part of the surface 20b of the body 20a of the preform with sandpaper or the like.

[0060] Next, the preform 10a is heated by the heating device 51 (see FIG. 6(b)). At this time, the preform 10a is heated uniformly in the circumferential direction by the heating device 51 while rotating with the mouth portion 11a facing downward. The heating temperature of the preform 10a in this heating step is, for example, 90°C to 130°C.

[0061] Separately, a blow molding die 50 is prepared. Then, the preform 10a heated by a heating device 51 is sent to the blow molding die 50 for producing the container body 10 (see FIG. 6(c)).

[0062] The container body 10 is molded using this blow molding die 50. In this embodiment, the blow molding die 50 has a die body 52 which is a metal die or a resin die. The die body 52 is composed of a pair of body dies 50a, 50b and a bottom die 50c which are separated from each other (see FIG. 6(c)). The inner surface of the die body 52 has a shape corresponding to the body 20 and the bottom 30 of the container body 10. In FIG. 6(c), the pair of body dies 50a, 50b are open from each other, and the bottom die 50c is raised upward. In this state, the preform 10a is inserted between the pair of body dies 50a, 50b of the die body 52.

[0063] Next, as shown in Fig. 6(d), the bottom mold 50c is lowered. After this, the pair of body molds 50a, 50b are closed. As a result, a blow molding mold 50 is formed that is sealed by the pair of body molds 50a, 50b and the bottom mold 50c of the mold body 52. ​​Next, air is forced into the preform 10a, and the preform 10a is subjected to biaxial stretch blow molding.

[0064] As a result, the preform 10a is shaped into a shape corresponding to the inner surface of the blow molding die 50, and the container body 10 is obtained from the preform 10a in the blow molding die 50. During this time, the body dies 50a and 50b are heated to 30°C to 80°C, and the bottom die 50c is cooled to 5°C to 25°C. In this manner, the container body 10 is obtained.

[0065] Thereafter, as shown in Fig. 6(e), the pair of body dies 50a, 50b and the bottom die 50c of the die body 52 are separated from each other, and the container body 10 is removed from the blow molding die 50. In this manner, the container body 10 shown in Figs. 1 and 2A is obtained.

[0066] As described above, the container body 10 of this embodiment is manufactured by blow molding the preform 10a heated by the heating device 51. At this time, the preform 10a is softened and easily stretched by being heated by the heating device 51. The preform 10a softened by heating is blow molded using the blow molding die 50, so that the preform 10a is shaped into a shape corresponding to the inner surface of the blow molding die 50. This allows the container body 10 to be manufactured in a desired shape.

[0067] However, if the preform 10a is not sufficiently heated by the heating device 51, the preform 10a may not be stretched so as to contact the entire inner surface of the blow molding die 50. In this case, it may not be possible to produce a container body 10 having a desired shape. In particular, when blow molding the preform 10a heated by the heating device 51 while keeping the output of the heating device 51 low, it is difficult to heat the preform 10a sufficiently. For this reason, when the output of the heating device 51 is kept low, the preform 10a may not be stretched so as to contact the entire inner surface of the blow molding die 50, and there is an increased risk that the container body 10 having the desired shape may not be produced.

[0068] In particular, the container body 10 of this embodiment has a shoulder portion 12. When manufacturing a container body 10 having such a shape, it is necessary to significantly stretch the neck portion 21 of the preform 10a, which corresponds to the shoulder portion 12 and the neck portion 13 of the container body 10. If the preform 10a is not sufficiently stretched at the neck portion 21 in manufacturing the container body 10 having the shoulder portion 12, there is a concern that the preform 10a will not come into contact with the inner surface of the blow molding die 50.

[0069] If the preform 10a is not sufficiently stretched at the neck 21 and a portion of the neck 21 does not contact the inner surface of the blow molding die 50, the shape around the shoulder 12 of the container body 10 may not be formed into the desired shape. For example, the angle between the neck 13 and the shoulder 12 of the container body 10 and between the shoulder 12 and the middle body 23 of the container body 10 with respect to the vertical direction of the surface 20d may not be formed into the desired shape. Furthermore, if the preform 10a is not sufficiently stretched at the neck 21, the above-mentioned meat pool 19 is formed at least in the shoulder 12 and the neck 13 of the container body 10. The meat pool 19 is formed by a thick portion remaining at the upper part of the neck 21 as a result of the preform 10a not being sufficiently stretched at the neck 21.

[0070] In particular, in order to sufficiently heat the preform 10a while keeping the output of the heating device 51 small, it is also assumed that the thickness of the preform 10a is made small. In this case, it is particularly difficult to manufacture the container body 10 having the desired thickness and shape. For example, if the thickness of the preform 10a is small, it is particularly difficult to control the thickness of the preform 10a to be uniform when stretching the preform 10a. Therefore, the area in which the meat pool 19, which is a part thicker than the middle part 23 of the container body 10, is formed in the container body 10 tends to become large. Furthermore, in the case of producing the container body 10 having the shoulder part 12, if the thickness of the preform 10a is small, it is particularly difficult to stretch the preform 10a so that the shape of the shoulder part 12 is formed such that the diameter gradually increases while controlling the thickness of the preform 10a to be uniform. Therefore, it is particularly difficult to form the shape around the shoulder part 12 of the container body 10 into the desired shape.

[0071] In contrast, in the preform 10a of this embodiment, a rough surface 20c is formed on a part of the surface 20b of the body portion 20a. When the rough surface 20c is formed on a part of the preform 10a, the surface area of ​​the preform 10a in that part increases. Therefore, the preform 10a is easily heated on the rough surface 20c. As a result, when the preform 10a is heated by the heating device 51, the part of the preform 10a where the rough surface 20c is formed can be heated so that the preform 10a is sufficiently softened. Therefore, during blow molding, the preform 10a can be stretched so as to contact the entire inner surface of the blow molding die 50, and the container body 10 of the desired shape can be produced.

[0072] The preform 10a may be easily heated at the rough surface 20c for the following reasons. It is also assumed that a device such as a heater may be used as the heating device 51. In this case, when the rough surface 20c is formed on a part of the preform 10a, light is easily diffused and reflected at the rough surface 20c. Therefore, the part of the preform 10a on which the rough surface 20c is formed exhibits a color closer to white than the part of the preform 10a on which the rough surface 20c is not formed. In such a preform 10a, the part on which the rough surface 20c is formed is more easily heated by thermal radiation than the part on which the rough surface 20c is not formed. This is also thought to be the reason why the preform 10a is easily heated at the rough surface 20c. As an example, the preform 10a transmits light. In this case, the preform 10a is less likely to transmit light at the part on which the rough surface 20c is formed than the part on which the rough surface 20c is not formed.

[0073] As an example, the L of the rough surface 20c * a * b * Lightness L in color system * The value of L is 80 or more. * a * b * Lightness L in color system *The value is measured in accordance with JIS Z8781-4:2013 using a spectrophotometer (CMS-35SP, manufactured by Murakami Color Research Laboratory Co., Ltd.). The measurement conditions are SCE (specular reflection excluded), 10° field of view, and D65 light source.

[0074] In particular, in this embodiment, the rough surface 20c is formed on the neck 21 of the preform 10a. This allows the neck 21 of the preform 10a, which corresponds to the shoulder 12 and neck 13 of the container body 10, to be sufficiently stretched during blow molding. This allows the container body 10 to be produced in a desired shape having the shoulder 12. Furthermore, the size of the filler pocket 19 formed on at least one of the shoulder 12 and neck 13 of the container body 10 can be kept small.

[0075] As described above, in the container body 10, the mass of the second portion 26 is not more than twice the mass of the third portion 27. In a plastic container body 10 of a general shape and size, the meat reservoir 19 is easily formed in the second portion 26. When the meat reservoir 19 is formed in the second portion 26, the mass of the second portion 26 increases. Therefore, the ratio of the mass of the second portion 26 to the mass of the third portion 27 increases. On the other hand, if the meat reservoir 19 is not formed in the second portion 26 or the meat reservoir 19 formed in the second portion 26 is small, the ratio of the mass of the second portion 26 to the mass of the third portion 27 decreases. In the container body 10 in which the mass of the second portion 26 is not more than twice the mass of the third portion 27, the size of the meat reservoir 19 formed in the second portion 26 is considered to be sufficiently small. Therefore, in the container body 10 in which the mass of the second portion 26 is less than twice the mass of the third portion 27, the size of the meat reservoir 19 is kept sufficiently small and it is considered to be manufactured in the desired shape.

[0076] As described above, the preform 10a of this embodiment includes the mouth portion 11a and the body portion 20a connected to the mouth portion 11a. A rough surface 20c that is rougher than the other parts of the surface 20b of the body portion 20a is formed in a part of the surface 20b of the body portion 20a. This makes it easier for the preform 10a to warm up at the rough surface 20c. This allows the preform 10a to be sufficiently softened by heating the part of the preform 10a where the rough surface 20c is formed. Therefore, during blow molding, the heated preform 10a can be stretched to produce a container body 10 of a desired shape.

[0077] According to the present embodiment, the arithmetic mean roughness Ra of the rough surface 20c is equal to or greater than 0.05 and equal to or less than 1.00, which makes it possible to more stably achieve the effect that the preform 10a is easily heated at the rough surface 20c.

[0078] According to this embodiment, the body 20a has a neck 21 connected to the mouth 11a, and a middle body 22 connected to the neck 21. The rough surface 20c is formed on the neck 21. This allows the neck 21 of the preform 10a, which corresponds to the shoulder 12 and neck 13 of the container body 10, to be sufficiently stretched when the container body 10 having the shoulder 12 is produced by blow molding. This allows the container body 10 to be produced in a desired shape having the shoulder 12.

[0079] According to this embodiment, the preform 10a further includes a bottom portion 30a connected to the body portion 20a. The arithmetic mean roughness Ra of the surface 20b of the bottom portion 30a is less than 0.05. This makes it easier for the portion of the surface 20b of the body portion 20a of the preform 10a, where the rough surface 20c is formed, to be stretched by heating.

[0080] The container body 10 of this embodiment includes a mouth 11, a body 20 connected to the mouth 11, and a bottom 30 connected to the body 20. The body 20 has a neck 13 connected to the mouth 11, a shoulder 12 connected to the neck 13, and a middle body 23 connected to the shoulder 12. When a portion of the neck 13 and the shoulder 12 that is 24.00 mm or more away from the boundary 25 between the mouth 11 and the neck 13 is defined as a first portion 24, the thickness of the first portion 24 is 1.2 times or less the thickness of the middle body 23. In such a container body 10, the size of the meat reservoir 19 is kept sufficiently small, and it is considered to be a container body 10 manufactured in a desired shape.

[0081] According to this embodiment, a rough surface 20e that is rougher than other parts of the surface 20d of the body 20 is formed in a part of the surface 20d of the body 20 of the container body 10. Such a container body 10 can be manufactured from a preform 10a in which a rough surface 20c is formed in a part of the surface 20b of the body 20a.

[0082] According to this embodiment, the rough surface 20e of the container body 10 is formed on at least one of the neck portion 13 and the shoulder portion 12. Such a container body 10 can be manufactured from a preform 10a in which the rough surface 20c is formed on the neck portion 21.

[0083] According to this embodiment, the mass of the portion (second portion 26) of the neck portion 13 and shoulder portion 12 of the container body 10 that is 15 mm or more and 25 mm or less away from the boundary 25 is not more than twice the mass of the portion (third portion 27) of the neck portion 13 and shoulder portion 12 of the container body 10 that is 25 mm or more and 35 mm or less away from the boundary 25. In such a container body 10, the size of the meat reservoir 19 is kept sufficiently small, and it is considered that the container body 10 is manufactured in the desired shape.

[0084] Next, various modified examples of this embodiment will be described with reference to Figures 7 to 12. In Figures 7 to 12, the same parts as those in the embodiment shown in Figures 1 to 6 are given the same reference numerals and detailed description thereof will be omitted.

[0085] (Variation 1) In the above-mentioned embodiment, the container body 10 in which the surface 20d of the bottom 30 does not have a rougher portion than the portion of the surface 20d of the body 20 in which the rough surface 20e is not formed has been described. In the above-mentioned embodiment, the preform 10a in which the surface 20b of the bottom 30a does not have a rougher portion than the portion of the surface 20b of the body 20a in which the rough surface 20c is not formed has been described. However, the configuration of the container body 10 and the preform 10a is not limited thereto. FIG. 7 is a vertical cross-sectional view showing the container body 10 according to the first modification. FIG. 8 is a vertical cross-sectional view showing the preform 10a used to manufacture the container body 10 shown in FIG. 7.

[0086] 7, a rough surface 20g is formed on the surface 20d of the bottom 30 of the container body 10, the rough surface 20g being rougher than a portion of the surface 20d of the trunk 20 where the rough surface 20e is not formed. The degree of roughness of the rough surface 20g is determined by the arithmetic mean roughness Ra.

[0087] In the preform 10a according to this modification, as shown in FIG. 8, the surface 20b of the bottom 30a may have a rough surface 20f formed thereon that is rougher than the portion of the surface 20b of the body 20a where the rough surface 20c is not formed. The degree of roughness of the rough surface 20f is determined by the arithmetic mean roughness Ra. The numerical range of the arithmetic mean roughness Ra of the rough surface 20f is, for example, the same as the numerical range of the arithmetic mean roughness Ra of the rough surface 20c. In the example shown in FIG. 8, the rough surface 20f is formed on the entire surface 20b of the bottom 30a. In this case, as shown in FIG. 7, a rough surface 20g may be formed on the surface 20d of the bottom 30 of the container body 10 produced from the preform 10a. In FIG. 7, the rough surface 20g is formed on the entire surface 20d of the bottom 30 of the container body 10. The method of forming the rough surface 20f is, for example, the same as the method of forming the rough surface 20c.

[0088] The rough surface 20f formed on the surface 20b of the bottom 30a provides the following effects. The bottom 30 of the container body 10 may have a complex shape. In order to manufacture the container body 10 having the bottom 30 of such a complex shape, it may be necessary to greatly stretch the bottom 30a of the preform 10a. The bottom 30 of the container body 10 shown in FIG. 7 has a recess 31 located at the center and a ground portion 32 provided around the recess 31. When forming the bottom 30 having the recess 31 and the ground portion 32, it is necessary to greatly stretch the bottom 30a of the preform 10a compared to the case of forming a flat bottom 30. The rough surface 20f formed on the surface 20b of the bottom 30a makes it easier for the preform 10a to warm up at the bottom 30a. This allows the bottom 30a to be stretched after being sufficiently softened by heating. As a result, the bottom portion 30a of the preform 10a can be stretched sufficiently widely.

[0089] On the other hand, according to the preform 10a in which the rough surface 20f is not formed on the surface 20b of the bottom portion 30a as shown in FIG. 3, as described above, the portion of the surface 20b of the body portion 20a in which the rough surface 20f is formed is more easily stretched.

[0090] (Variation 2) Modification 2 relates to a composite container 10A including the container body 10 described above in the embodiment and a plastic member 40 provided on the outside of the container body 10. Furthermore, modification 2 relates to a composite preform 70 including the preform 10a described above in the embodiment and a plastic member 40a provided on the outside of the preform 10a. Fig. 9 is a vertical cross-sectional view showing the composite container 10A according to modification 2. Fig. 10 is a vertical cross-sectional view showing a composite preform 70 used to produce the composite container 10A shown in Fig. 9.

[0091] The composite container 10A shown in FIG. 9 includes a container body 10 made of a plastic material located on the inside, and a plastic member 40 provided in close contact with the outside of the container body 10. The composite preform 70 shown in FIG. 10 includes a preform 10a and a plastic member 40a. The composite container 10A shown in FIG. 9 is obtained by the following method. The composite preform 70 including the preform 10a and the plastic member 40a shown in FIG. 10 is subjected to biaxial stretch blow molding using a blow molding die 50. This causes the preform 10a and the plastic member 40a to expand as a unit. This forms the plastic member 40 from the plastic member 40a, and the composite container 10A shown in FIG. 9 is obtained.

[0092] The plastic member 40 of the composite container 10A will be described. The plastic member 40 is formed by closely adhering a plastic member 40a (described later) to the outside of the preform 10a, and then stretching the plastic member 40a together with the preform 10a. This results in a composite container 10A comprising the container body 10 and the plastic member 40. The plastic member 40 is adhered to the outer surface of the container body 10 in a thinly stretched state, and is attached in a state in which it does not easily move or rotate relative to the container body 10.

[0093] In the composite container 10A, the plastic member 40 is attached to the outer surface of the container body 10 without being bonded. The plastic member 40 is in close contact with the container body 10 so that it does not move or rotate relative to the container body 10. This plastic member 40 is stretched thinly on the outer surface of the container body 10 to cover the container body 10. The plastic member 40 is provided over the entire circumferential direction so as to surround the container body 10, and has a horizontal cross section that is approximately circular.

[0094] 9, the plastic member 40 covers the container body 10 except for the mouth portion 11 and a part of the body portion 20. The plastic member 40 covers a part of the body portion 20 and the bottom portion 30 of the container body 10. This makes it possible to impart a desired function or characteristic to the part of the body portion 20 and the bottom portion 30 of the container body 10.

[0095] In the composite container 10A, the plastic member 40 is not welded or bonded to the container body 10, and can therefore be peeled off and removed from the container body 10. Specifically, the plastic member 40 can be cut off using, for example, a blade or the like. It is also possible to provide a cutting line (not shown) in advance on the plastic member 40, and peel off the plastic member 40 along this cutting line. This allows the plastic member 40 to be separated and removed from the container body 10.

[0096] In the composite container 10A, there is no particular limitation on the thickness of the plastic member 40. The thickness of the plastic member 40 when attached to the container body 10 is, for example, 5 μm or more and 500 μm or less.

[0097] An explanation will be given of the plastic member 40a of the composite preform 70. The plastic member 40a of the composite preform 70 does not have to have a shrinking action relative to the preform 10a, or it may have a shrinking action.

[0098] When the plastic member 40a has a shrinking effect relative to the preform 10a, the plastic member (outer shrink member) 40a is provided on the outside of the preform 10a. In this case, the plastic member 40a is heated together with the preform 10a and biaxially stretched and blow molded.

[0099] In the composite preform 70 shown in Fig. 10, the plastic member 40a is attached to the outer surface of the preform 10a without being bonded. The plastic member 40a is in close contact with the preform 10a so that it does not move or rotate, or so that it does not fall under its own weight. The plastic member 40a is provided over the entire circumferential area of ​​the preform 10a so as to surround it. The plastic member 40a has a circular horizontal cross section.

[0100] In FIG. 10, the plastic member 40a is provided on a part of the body portion 20a and the entire area of ​​the bottom portion 30a of the preform 10a.

[0101] When the plastic member 40a has a shrinking action, the plastic member (outer shrinking member) 40a may be one that shrinks (e.g., thermally shrinks) relative to the preform 10a when an external action (e.g., heat) is applied to it. The plastic member (outer shrinking member) 40a may itself have shrinkability or elasticity and may be capable of shrinking without the application of an external action.

[0102] If the plastic member 40a has a thermal shrinkage function, after the cylindrical plastic member 40a is fitted into the preform 10a, the margin formed at the lower end portion (the end portion opposite the mouth portion 11a) of the plastic member 40a may be thermally compressed.

[0103] Examples of the plastic member 40a that can be used include a direct blow tube produced by direct blow molding, a sheet molded tube produced by sheet molding, an extrusion tube produced by extrusion molding, an injection molded tube produced by injection molding, and an inflation molded tube produced by inflation molding, but the plastic member 40a is not limited to these and molding methods other than those mentioned above may also be used.

[0104] The shape of the plastic member 40a in the composite preform 70 is not particularly limited as long as it can be attached to the outer surface of the preform 10a. The plastic member 40a may be formed into a cylindrical shape with a bottom as a whole, as shown in FIG. 11(a). In this case, the plastic member 40a may have a cylindrical body 41 and a bottom 42 connected to the body 41. In this case, the bottom 30a of the preform 10a can be covered with the bottom 42 of the plastic member 40a. This allows various functions and characteristics such as barrier properties to be imparted to the bottom 30 in addition to the body 20 of the container body 10. Such a plastic member 40a is, for example, the above-mentioned direct blow tube, sheet molding tube, or injection molding tube.

[0105] 11(b), in the composite preform 70, the plastic member 40a may be formed in a circular tubular shape (bottomless cylindrical shape) as a whole, and may have a cylindrical body portion 41. In this case, the plastic member 40a may be, for example, the above-mentioned blow tube, extrusion tube, inflation molding tube, or sheet molding tube.

[0106] In the composite preform 70, the plastic member 40a may be produced by forming a film into a cylindrical shape and bonding the ends together, as shown in Figures 11(c) and 11(d). In this case, the plastic member 40a may be configured in a tubular shape (bottomless cylindrical shape) having a body 41, as shown in Figure 11(c). The plastic member 40a may be configured in a bottomed cylindrical shape by bonding a bottom 42 together, as shown in Figure 11(d).

[0107] Examples of the plastic member 40 (plastic member 40a) include polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, poly-4-methylpentene-1, polystyrene, AS resin, ABS resin, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyvinyl alcohol, polyvinyl acetal, polyvinyl butyral, diallyl phthalate resin, fluorine-based resin, polymethyl methacrylate, polyacrylic acid, polymethyl acrylate, polyacrylonitrile, polyacrylamide, polybutadiene, polybutene-1, polyisoprene, polychloroprene, ethylene propylene rubber, butyric acid, polyvinyl chloride ... chloride, polyvinyl chloride, polyvinyl chloride, polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polyvinyl acetal, polyvinyl butyral, diallyl phthalate resin, fluorine-based resin, polymethyl methacrylate, polyacrylic acid, polymethyl acrylate, polyacrylonitrile, polyacrylamide, polybutadiene, polybutene-1, polyisoprene, polychloroprene, ethylene propylene rubber, butyric acid, polyvinyl chloride Examples of the resin include ethylene rubber, nitrile rubber, acrylic rubber, silicone rubber, fluororubber, nylon 6, nylon 6,6, aromatic polyamide, polycarbonate, polyethylene terephthalate, butylene polyethylene terephthalate, ethylene polynaphthalate, U polymer, liquid crystal polymer, modified polyphenylene ether, polyether ketone, polyether ether ketone, unsaturated polyester, alkyd resin, polyimide, polysulfone, polyphenylene sulfide, polyether sulfone, silicone resin, polyurethane, phenolic resin, urea resin, polyethylene oxide, polypropylene oxide, polyacetal, and epoxy resin. Among these, it is preferable to use thermoplastic non-elastic resins such as polyethylene (PE) such as low-density polyethylene (LDPE), polypropylene (PP), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN). The plastic member 40 (plastic member 40a) may be a blend of the above-mentioned resins, or a combination of the above-mentioned resins in a multi-layer structure or a partially multi-layer structure. Furthermore, various additives other than the main resin may be added to the material of the plastic member 40 (plastic member 40a) to the extent that the characteristics are not impaired. Examples of additives that can be added include plasticizers, UV stabilizers, color inhibitors, matting agents, deodorants, flame retardants, weather resistance agents, antistatic agents, thread friction reducers, slip agents, mold release agents, antioxidants, ion exchange agents, and color pigments.By mixing inert gas (nitrogen gas, argon gas) into the molten thermoplastic resin, it is possible to use a foamed material with a foam cell diameter of 0.5 μm to 100 μm. By molding this foamed preform, it is possible to improve the light blocking properties.

[0108] The plastic member 40 (plastic member 40a) may be made of a material having a light barrier property that blocks invisible light such as ultraviolet light. In this case, the light barrier property of the composite container 10A can be improved without using a multi-layer preform or a preform containing a blended material as the preform 10a. This makes it possible to prevent the content liquid from being deteriorated by ultraviolet light or the like. Such a material is, for example, a blended material, or a material in which a light-shielding resin is added to PET, PE, or PP. A foamed member having a foam cell diameter of 0.5 μm or more and 100 μm or less, which is produced by mixing an inert gas (nitrogen gas, argon gas) with a melt of a thermoplastic resin, may also be used.

[0109] The plastic member 40 (plastic member 40a) may be made of a material with higher cold insulation or heat insulation (material with lower thermal conductivity) than the plastic material constituting the container body 10 (preform 10a). In this case, it is possible to make it difficult for the temperature of the content liquid to be transmitted to the surface of the composite container 10A without increasing the thickness of the container body 10 itself. This improves the cold insulation or heat insulation of the composite container 10A. Furthermore, when a user grasps the composite container 10A, it is prevented that the composite container 10A becomes difficult to hold due to being too cold or too hot. Such materials include, for example, foamed polyurethane, polystyrene, PE (polyethylene), PP (polypropylene), phenolic resin, polyvinyl chloride, urea resin, silicone, polyimide, melamine resin, etc. It is preferable to mix hollow particles with a resin material containing these resins to form the plastic member 40 (plastic member 40a). The hollow particles may be organic hollow particles composed of resin, etc. The hollow particles may be inorganic hollow particles composed of glass, etc. The hollow particles are preferably organic hollow particles because of their excellent dispersibility. Examples of the resins constituting the organic hollow particles include styrene resins such as crosslinked styrene-acrylic resins, (meth)acrylic resins such as acrylonitrile-acrylic resins, phenol resins, fluorine resins, polyamide resins, polyimide resins, polycarbonate resins, and polyether resins. As the hollow particles, commercially available hollow particles such as Ropeake HP-1055, Ropeake HP-91, Ropeake OP-84J, Ropeake Ultra, Ropeake SE, and Ropeake ST (manufactured by Rohm and Haas Co., Ltd.), Nipol MH-5055 (manufactured by Zeon Corporation), SX8782, and SX866 (manufactured by JSR Corporation) can also be used. The content of the hollow particles is preferably 0.01 parts by mass or more and 50 parts by mass or less, and more preferably 1 part by mass or more and 20 parts by mass or less, relative to 100 parts by mass of the resin material contained in the plastic member 40.

[0110] The plastic member 40 (plastic member 40a) may be made of a material that is less slippery than the plastic material that constitutes the container body 10 (preform 10a). In this case, the user can easily grip the composite container 10A without changing the material of the container body 10.

[0111] The plastic member 40 (plastic member 40a) may be colored in a color such as red, blue, yellow, green, brown, black, or white, and may be transparent or opaque.

[0112] Method for manufacturing preforms and containers Next, a manufacturing method (blow molding method) for the composite container 10A according to Modification 2 will be described with reference to FIGS. 12(a) and 12(b).

[0113] First, a preform 10a made of a plastic material is prepared (see FIG. 12(a)). The method for preparing the preform 10a is the same as the method for preparing the composite preform 70 made of the preform 10a in the above-mentioned embodiment, for example.

[0114] Next, a plastic member 40a is provided on the outside of the preform 10a to produce a composite preform 70 having the preform 10a and the plastic member 40a attached to the outside of the preform 10a (see FIG. 12(b)). In this case, the plastic member 40a has a bottomed cylindrical shape as a whole, and has a cylindrical body 41 and a bottom 42 connected to the body 41.

[0115] At this time, a plastic member 40a having an inner diameter equal to or slightly smaller than the outer diameter of the preform 10a may be pressed into the preform 10a to be brought into close contact with the outer surface of the preform 10a. As described below, a heat-shrinkable plastic member 40a may be provided on the outer surface of the preform 10a, and the plastic member 40a may be heated to 50°C to 100°C to cause heat shrinkage and bring the plastic member 40a into close contact with the outer surface of the preform 10a.

[0116] In the manufacturing method of the second modified example, as described above, the plastic member 40a is first attached to the outside of the preform 10a to produce the composite preform 70. This allows a series of steps for producing the composite preform 70 and a series of steps for producing the composite container 10A by blow molding to be carried out in separate locations (such as factories).

[0117] Next, the composite preform 70 is heated by the heating device 51, and the heated composite preform 70 is blow molded. The method of heating the composite preform 70 is, for example, the same as the method of heating the preform 10a in the above-mentioned embodiment. The method of blow molding the composite preform 70 is, for example, the same as the method of blow molding the preform 10a in the above-mentioned embodiment. The composite container 10A is manufactured by blow molding the composite preform 70 heated by the heating device 51.

[0118] Next, a specific example of the above embodiment will be described.

[0119] Example 1 First, the container body 10 shown in Figures 1 and 2A was produced. The container body 10 was manufactured by the manufacturing method shown in Figures 6(a) to (e).

[0120] That is, first, the preform 10a shown in FIG. 6(a) was prepared. A rough surface 20c was formed on a part of the surface of this preform 10a. In Example 1, the rough surface 20c was formed on the entire surface of the part constituting the neck part 21 of the preform 10a. The rough surface 20f was not formed on the part constituting the bottom part 30a of the preform 10a. The rough surface 20c was formed by rubbing sandpaper on the surface of the preform 10a. The rough surface 20c was formed so that the arithmetic mean roughness Ra was 0.9 μm. The arithmetic mean roughness Ra was measured using a surface roughness measuring instrument (product name "SURFCOM1400G", manufactured by Tokyo Seimitsu Co., Ltd.) in accordance with JIS B0601:2013. In this way, the preform 10a having the rough surface 20c formed on a part of the surface was produced. The arithmetic mean roughness Ra of the produced container body 10 in the portion of the surface 20b where the rough surface 20c was not formed was 0.02 μm.

[0121] Next, as shown in FIG. 6(b), the preform 10a was heated by a heating device 51. Furthermore, a mold body 52 as shown in FIG. 6(c) was prepared. Next, as shown in FIG. 6(c), the preform 10a was inserted between the pair of body dies 50a, 50b of the mold body 52. ​​Next, as shown in FIG. 6(d), a blow molding mold 50 was constructed, which was sealed by the pair of body dies 50a, 50b and the bottom die 50c of the mold body 52. ​​Then, air was forced into the preform 10a, and the preform 10a was subjected to biaxial stretch blow molding. This allowed the preform 10a to be shaped into a shape corresponding to the inner surface of the blow molding mold 50. After that, as shown in FIG. 6(e), the pair of body dies 50a, 50b and the bottom die 50c of the mold body 52 were separated from each other, and the container body 10 was taken out of the blow molding mold 50. This allowed the container body 10 to be produced. In the produced container body 10, the distance w2 in the up-down direction between the boundary 25 between the mouth portion 11 and the neck portion 13 and the boundary 28 between the shoulder portion 12 and the central body portion 23 was 35 mm or more.

[0122] (1) Evaluation test of meat pool Next, an evaluation test of the meat pool 19 was carried out on the obtained container body 10.

[0123] At this time, the thicknesses of the shoulder portion 12, the neck portion 13, and the middle body portion 23 were measured by a vernier caliper. As a result of the measurement by the vernier caliper, it was found that the thick-walled region 18, which is a region whose thickness is 1.2 times or more than the thickness of the middle body portion 23, was formed in the shoulder portion 12 and the neck portion 13. Then, the distance w5 from the boundary 25 to the lower end of the thick-walled region 18 was measured. In this case, it can be evaluated that the smaller the distance w5, the smaller the size of the meat pool 19 is. In particular, if the distance w5 is less than 24.00 mm, it can be evaluated that the thickness t3 of the first portion 24 described above is 1.2 times or less the thickness t1 of the middle body portion 23, and the size of the meat pool 19 is sufficiently small. The measurement of the distance w5 was performed for each of the container bodies 10 produced after producing 20 container bodies 10.

[0124] (2) Weight distribution evaluation test Furthermore, an evaluation test of the weight distribution was carried out on the obtained container body 10.

[0125] At this time, the mass of the portion (second portion 26) of the neck portion 13 and shoulder portion 12 of the container body 10 that is 15 mm or more and 25 mm or less from the boundary 25 between the mouth portion 11 and the neck portion 13 was measured. Furthermore, the mass of the portion (third portion 27) of the neck portion 13 and shoulder portion 12 of the container body 10 that is 25 mm or more and 35 mm or less from the boundary 25 between the mouth portion 11 and the neck portion 13 was measured. Furthermore, the mass of the portion (third portion 27) of the neck portion 13 and shoulder portion 12 of the container body 10 that is 0 mm or more and 15 mm or less from the boundary 25 between the mouth portion 11 and the neck portion 13 was measured. The portion (fourth portion 29) of the neck portion 13 and shoulder portion 12 of the container body 10 that is 0 mm or more and 15 mm or less from the boundary 25 between the mouth portion 11 and the neck portion 13 is also referred to as the fourth portion 29. In measuring the masses of the second portion 26, the third portion 27, and the fourth portion 29, the second portion 26, the third portion 27, and the fourth portion 29 were separated from the other portions of the container body 10, and the masses were measured using a scale. In this case, it can be evaluated that the smaller the ratio of the mass of the second portion 26 to the mass of the third portion 27, the smaller the size of the meat reservoir 19 is. The masses of the second portion 26, the third portion 27, and the fourth portion 29 were measured for each of the container bodies 10 produced after producing 20 container bodies 10.

[0126] Example 2 A rough surface 20c was formed on the entire surface of the portion of the preform 10a that constitutes the neck portion 21. A rough surface 20f was formed on the entire surface of the portion of the preform 10a that constitutes the bottom portion 30a. A container body 10 was manufactured by the same method as in Example 1 except for this point. For this container body 10, an evaluation test of the meat pool 19 and an evaluation test of the weight distribution were performed in the same manner as in Example 1.

[0127] Comparative Example 1 A preform 10a having no rough surface 20c and no rough surface 20f formed on the surface was used. Except for this, the container body 10 was manufactured in the same manner as in Example 1. For this container body 10, an evaluation test of the meat pool 19 and an evaluation test of the weight distribution were performed in the same manner as in Example 1.

[0128] Comparative Example 2 A rough surface 20f was formed on the entire surface of the portion of the preform 10a that constitutes the bottom portion 30a. A rough surface 20c was not formed on the portion of the preform 10a that constitutes the neck portion 21. A container body 10 was manufactured by the same method as in Example 1 except for this point. For this container body 10, an evaluation test of the meat pool 19 and an evaluation test of the weight distribution were performed in the same manner as in Example 1.

[0129] (Test Results) The results of the evaluation test of the meat puddle 19 are shown in Table 2. The "Average" column in Table 2 shows the average value of the results of measuring the distance w5 for multiple container bodies 10. The "Maximum" column in Table 2 shows the maximum value of the results of measuring the distance w5 for multiple container bodies 10. The "Minimum" column in Table 2 shows the minimum value of the results of measuring the distance w5 for multiple container bodies 10.

[0130] [Table 2]

[0131] As a result, as shown in Table 2, in Examples 1 and 2, the distance w5 was smaller than in Comparative Examples 1 and 2. In particular, in Examples 1 and 2, the distance w5 was 24.00 mm or less. On the other hand, in Comparative Examples 1 and 2, the distance w5 was greater than 24.00 mm. From this, it was found that the size of the meat pool 19 was kept smaller in Examples 1 and 2 than in Comparative Examples 1 and 2. In particular, in Examples 1 and 2, the thickness t3 of the first portion 24 described above was 1.2 times or less the thickness t1 of the middle trunk portion 23, and it was found that the size of the meat pool 19 was kept sufficiently small.

[0132] Furthermore, as shown in Table 2, the distance w5 was smaller in Example 1 than in Example 2. From this, it was found that in Example 1, the portion where the rough surface 20c of the surface 20b of the body 20a is formed is more easily stretched than in Example 2, and the size of the meat pool 19 is suppressed to be small. As described above, in the preform 10a of Example 1, the rough surface 20f is not formed on the surface 20b of the bottom 30a. In the preform 10a of Example 2, the rough surface 20f is formed on the surface 20b of the bottom 30a. From the above, it was found that when the rough surface 20f is not formed on the surface 20b of the bottom 30a, the portion where the rough surface 20c of the surface 20b of the body 20a is formed is more easily stretched than when the rough surface 20f is formed on the surface 20b of the bottom 30a.

[0133] The results of the weight distribution evaluation test are shown in Table 3. The "Average" column in Table 3 shows the average value of the results of measuring the masses of second portion 26, third portion 27, and fourth portion 29. The "Maximum" column in Table 3 shows the maximum value of the results of measuring the masses of second portion 26, third portion 27, and fourth portion 29. The "Minimum" column in Table 3 shows the minimum value of the results of measuring the masses of second portion 26, third portion 27, and fourth portion 29.

[0134] [Table 3]

[0135] As a result, as shown in Table 3, the mass of second portion 26 was smaller in Examples 1 and 2 than in Comparative Examples 1 and 2. In particular, the mass of second portion 26 was 1.00 g or less in Examples 1 and 2. On the other hand, the mass of second portion 26 was greater than 1.00 g in Comparative Examples 1 and 2. In contrast, regarding the masses of third portion 27 and fourth portion 29, the difference in mass was small between Examples 1 and 2 and Comparative Examples 1 and 2.

[0136] In Examples 1 and 2, the ratio of the mass of the second portion 26 to the mass of the third portion 27 was smaller than in Comparative Examples 1 and 2. In particular, in Examples 1 and 2, even when comparing the maximum value of the mass of the second portion 26 with the minimum value of the mass of the third portion 27, the mass of the second portion 26 was less than twice the mass of the third portion 27. On the other hand, in Comparative Examples 1 and 2, even when comparing the minimum value of the mass of the second portion 26 with the maximum value of the mass of the third portion 27, the mass of the second portion 26 was more than twice the mass of the third portion 27. From this, it was found that the size of the meat reservoir 19 was smaller in Examples 1 and 2 than in Comparative Examples 1 and 2.

[0137] It is also possible to combine the multiple components disclosed in the above embodiments as necessary, or to delete some of the components disclosed in the above embodiments. [Explanation of symbols]

[0138] 10 Container body 10A composite container 10a Preform 11 Mouth 11a Mouth 12 Shoulder 13 Neck 20 Torso 20a Torso 20b surface 20c Rough surface 20d surface 20e Rough surface 21 Neck 22 Middle torso 23 Middle torso 30 bottom 30a bottom 70 Composite preform

Claims

1. The mouth part, a body portion connected to the mouth portion, A preform, wherein a part of the surface of the body portion is formed with a rough surface that is rougher than other parts of the surface of the body portion.

2. The preform according to claim 1 , wherein the rough surface has an arithmetic mean roughness Ra of 0.05 or more and 1.00 or less.

3. The body portion has a neck portion connected to the mouth portion and a middle portion connected to the neck portion, The preform of claim 1 , wherein the roughened surface is formed on the neck portion.

4. Further comprising a bottom portion connected to the body portion, The preform according to claim 1 , wherein the arithmetic mean roughness Ra of the surface of the bottom portion is less than 0.

05.

5. A preform according to any one of claims 1 to 4; and a plastic member provided on the exterior of the preform.

6. A container body including a mouth portion, a body portion connected to the mouth portion, and a bottom portion connected to the body portion, The body portion has a neck portion connected to the mouth portion, a shoulder portion connected to the neck portion, and a middle portion connected to the shoulder portion, A container body, wherein when the portion of the neck and shoulder that is 24.00 mm or more away from the boundary between the mouth and the neck is defined as a first portion, the thickness of the first portion is 1.2 times or less the thickness of the middle body portion.

7. The container body according to claim 6 , wherein a part of the surface of the body portion is formed with a rough surface that is rougher than other parts of the surface of the body portion.

8. The container body according to claim 7 , wherein the rough surface is formed on at least one of the neck portion and the shoulder portion.

9. The container body of claim 6, wherein when the portion of the neck and shoulder that is 15 mm or more and 25 mm or less away from the boundary is defined as a second portion, and the portion of the neck and shoulder that is 25 mm or more and 35 mm or less away from the boundary is defined as a third portion, the mass of the second portion is less than twice the mass of the third portion.

10. A container body according to any one of claims 6 to 9, A composite container comprising a plastic member provided on the outside of the container body.

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