JP2018202707A - Composite preform and production method thereof, composite container and production method thereof, and heat shrinkable plastic member - Google Patents

Abstract

To provide a composite preform and a production method thereof capable of achieving a more preferable appearance on a bottom part on a composite container, a composite container and a production method thereof, and a heat shrinkable plastic member.SOLUTION: A plastic material preform 10a comprising a mouth part 11a, a trunk 20a, and a bottom part 30a is prepared. A cylindrical heat shrinkable plastic member 40a comprising one end 41a and the other end 41b is prepared, in the heat shrinkable plastic member 40a, each of a first notch 49a and a second notch 49b is formed on each of facing positions of the one end 41a. Then, the heat shrinkable plastic member 40a is loosely inserted into the preform 10a from the other end 41b side, then the heat shrinkable plastic member 40a is subjected to heat shrinkage, thereby bringing the heat shrinkable plastic member 40a into tight contact with outside of the preform 10a.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a composite preform and a manufacturing method thereof, a composite container and a manufacturing method thereof, and a heat-shrinkable plastic member.

  Recently, plastic bottles for storing content liquids such as foods and drinks have become common, and such plastic bottles store content liquids.

  A plastic bottle containing such a content liquid is manufactured by inserting a preform into a mold and biaxially stretch-blow molding.

  By the way, in the conventional biaxial stretch blow molding method, for example, a preform including a single layer material such as PET or PP, a multilayer material, a blend material, or the like is used to form a container shape. However, in the conventional biaxial stretch blow molding method, the preform is generally simply formed into a container shape. For this reason, when various functions and characteristics (barrier property, heat retaining property, etc.) are given to the container, the means is limited, for example, by changing the material constituting the preform.

International Publication No. 2014/208746

  On the other hand, in order to solve the above problems, the present inventors have provided a composite container provided with various functions and characteristics such as light-shielding properties, a composite preform used when producing a composite container, and these A manufacturing method is proposed (see Patent Document 1). On the other hand, in producing such a composite container, a heat-shrinkable plastic member may be used as the plastic member. However, when using a heat-shrinkable plastic member, the appearance and There is a demand for better light shielding properties.

  The present invention has been made in consideration of such points, and among composite containers, in particular, a composite preform and a manufacturing method thereof, a composite container and a manufacturing method thereof capable of improving the appearance at the bottom, It is another object of the present invention to provide a heat shrinkable plastic member.

  The present invention relates to a method for producing a composite preform, a step of preparing a preform made of a plastic material having a mouth portion, a body portion, and a bottom portion, and a tubular heat-shrinkable plastic member having one end and the other end A step of preparing a heat-shrinkable plastic member in which a first cut portion and a second cut portion are formed at positions opposite to each other on the one end, and the heat-shrinkable plastic member, A step of loosely inserting the heat-shrinkable plastic member from the other end side, and a step of heat-shrinking the heat-shrinkable plastic member to bring the heat-shrinkable plastic member into close contact with the outside of the preform. A method for producing a composite preform, comprising:

  The present invention provides a method for manufacturing a composite preform, the step of preparing a preform made of a plastic material having a mouth portion, a body portion, and a bottom portion, the step of preparing a heat shrinkable plastic member, and the heat shrinkability Loosely inserting a plastic member into the preform, heat-shrinking the heat-shrinkable plastic member, and bringing the heat-shrinkable plastic member into close contact with the outside of the preform; A method for manufacturing a composite preform, comprising: a step of forming a first cut portion and a second cut portion at opposite positions of one end on the open side of a heat-shrinkable plastic member. .

  According to the present invention, a first piece and a second piece separated from each other by the first cut portion and the second cut portion are formed at the one end of the heat shrinkable plastic member. A method for manufacturing a composite preform, comprising a step of crimping a part of the first piece and a part of the second piece to each other after the step of thermally shrinking the member.

  The present invention relates to a method of manufacturing a composite container, the step of producing a composite preform by the method of manufacturing the composite preform, and blow molding the preform of the composite preform and the heat shrinkable plastic member. And a step of expanding the preform and the heat-shrinkable plastic member as a unit by applying the method.

  In the composite preform, the present invention includes a preform made of a plastic material having a mouth portion, a body portion, and a bottom portion, and a cylindrical heat-shrinkable plastic member provided so as to surround the outside of the preform. The heat-shrinkable plastic member has a cylindrical large-diameter portion that covers at least the body portion of the preform, and a reduced-diameter portion that extends outward from the bottom portion of the preform, The composite preform is characterized in that a first cut portion and a second cut portion are formed at positions of the reduced diameter portion facing each other.

  In the present invention, a first piece and a second piece separated from each other by the first cut portion and the second cut portion are formed in the reduced diameter portion, and a part of the first piece and the second piece are formed. It is a composite preform characterized in that a part of the piece is bonded to each other.

  The present invention is a composite container which is a blow-molded product of the composite preform, and is made of a heat-shrinkable plastic provided in close contact with the outside of the container main body, and a container main body having a mouth, a trunk and a bottom. The heat-shrinkable plastic member is crimped at a position covering the bottom of the container body.

  The present invention is a heat-shrinkable plastic member that is mounted so as to surround the outside of the preform, and includes a cylindrical main body portion having one end and the other end, and the one end is opposed to each other, respectively. The heat-shrinkable plastic member is characterized in that a first cut portion and a second cut portion are formed.

  According to the present invention, it is possible to improve the appearance of the composite container, particularly at the bottom.

FIG. 1 is a partial vertical sectional view showing a composite container according to an embodiment of the present invention. FIG. 2 is a horizontal sectional view (sectional view taken along the line II-II in FIG. 1) showing the composite container according to the embodiment of the present invention. FIG. 3 is a partial vertical sectional view showing a composite preform according to an embodiment of the present invention. FIG. 4 is a perspective view showing the periphery of the bottom of the composite preform according to the embodiment of the present invention. FIG. 5 is a perspective view showing a heat-shrinkable plastic member before heat shrinkage. FIGS. 6A to 6G are schematic views showing a method for producing a composite preform and a method for producing a composite container according to an embodiment of the present invention. FIG. 7 is a perspective view showing the periphery of the bottom of a composite preform according to a modification of the present invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 to 6 show an embodiment of the present invention.

(Composition of composite container)
First, an outline of the composite container according to the present embodiment will be described with reference to FIGS. 1 and 2. In the present specification, “upper” and “lower” refer to the upper side and the lower side in a state where the composite container 10A is erected (FIG. 1), respectively.

  The composite container 10A shown in FIG. 1 and FIG. 2 is compared with a composite preform 70 (see FIG. 3) including a preform 10a and a heat-shrinkable plastic member 40a using a blow molding die 50, as will be described later. By performing biaxial stretching blow molding, the preform 10a of the composite preform 70 and the heat-shrinkable plastic member 40a are integrally expanded.

  Such a composite container 10 </ b> A includes a container body 10 made of a plastic material positioned inside and a heat-shrinkable plastic member 40 provided in close contact with the outside of the container body 10.

  Among these, the container body 10 includes a mouth portion 11, a neck portion 13 provided below the mouth portion 11, a shoulder portion 12 provided below the neck portion 13, a trunk portion 20 provided below the shoulder portion 12, And a bottom portion 30 provided below the portion 20.

  On the other hand, the heat-shrinkable plastic member 40 is in close contact with the outer surface of the container body 10 in a thinly extended state, and is attached to the container body 10 without being easily moved or rotated.

  Next, the container body 10 will be described in detail. As described above, the container body 10 includes the mouth portion 11, the neck portion 13, the shoulder portion 12, the trunk portion 20, and the bottom portion 30.

  Of these, the mouth portion 11 includes a screw portion 14 screwed into a cap (not shown) and a flange portion 17 provided below the screw portion 14. The shape of the mouth portion 11 may be a conventionally known shape.

  The neck portion 13 is located between the flange portion 17 and the shoulder portion 12 and has a substantially cylindrical shape having a substantially uniform diameter. The shoulder 12 is located between the neck 13 and the trunk 20 and has a shape whose diameter gradually increases from the neck 13 toward the trunk 20.

  Furthermore, the trunk | drum 20 has a cylindrical shape with a substantially uniform diameter as a whole. However, the present invention is not limited to this, and the body portion 20 may have a polygonal cylindrical shape such as a rectangular cylindrical shape or an octagonal cylindrical shape. Or the trunk | drum 20 may have a cylinder shape with a horizontal cross section which is not uniform toward upper direction from the downward direction. Moreover, in this Embodiment, although the unevenness | corrugation is not formed in the trunk | drum 20, and has a substantially flat surface, it is not restricted to this. For example, unevenness such as a panel or a groove may be formed on the body portion 20.

  On the other hand, the bottom portion 30 has a concave portion 31 located in the center and a grounding portion 32 provided around the concave portion 31. The shape of the bottom 30 is not particularly limited, and may have a conventionally known bottom shape (for example, a petaloid bottom shape or a round bottom shape).

  Moreover, the thickness of the container main body 10 in the trunk | drum 20 is not limited to this, For example, it can be made thin about 50 micrometers or more and 250 micrometers or less. Furthermore, the weight of the container body 10 is not limited to this, but can be 10 g or more and 20 g or less. Thus, by reducing the thickness of the container main body 10, the weight of the container main body 10 can be reduced.

  Such a container main body 10 can be manufactured by biaxially stretching blow-molding a preform 10a (described later) manufactured by injection molding a synthetic resin material. As the material of the preform 10a, that is, the container body 10, a thermoplastic resin, particularly PE (polyethylene), PP (polypropylene), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), or PC (polycarbonate) may be used. preferable. 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. Moreover, you may blend and use the various resin mentioned above. Further, a vapor deposition film such as a diamond-like carbon film or a silicon oxide thin film may be formed on the inner surface of the container body 10 in order to enhance the barrier property of the container.

  The container body 10 can also be formed as a multilayer molded bottle having two or more layers. That is, by extrusion molding or injection molding, for example, the intermediate layer has gas barrier properties and light shielding properties such as MXD6, MXD6 + fatty acid salt, PGA (polyglycolic acid), EVOH (ethylene vinyl alcohol copolymer) or PEN (polyethylene naphthalate). You may form as a multilayer bottle which has gas barrier property and light-shielding property by shape | molding the preform 10a which consists of 3 or more layers as resin which has (intermediate layer), and carrying out blow molding. As the intermediate layer, a resin obtained by blending the above-described various resins may be used.

  In addition, by mixing an inert gas (nitrogen gas, argon gas) with the melt of thermoplastic resin, a foam preform having a foam cell diameter of 0.5 μm or more and 100 μm or less is formed, and this foam preform is blow-molded. By doing so, the container body 10 may be produced. Since such a container main body 10 contains the foam cell, the light shielding property of the container main body 10 whole can be improved.

  Such a container main body 10 may consist of bottles with a full capacity of 100 ml or more and 2000 ml or less, for example. Alternatively, the container body 10 may be a large bottle having a full capacity of, for example, 10L to 60L.

  Next, the heat shrinkable plastic member 40 will be described. As will be described later, the heat-shrinkable plastic member 40 (40a) is provided so as to surround the outside of the preform 10a, and after being in close contact with the outside of the preform 10a, it is biaxially stretch blow molded together with the preform 10a. Is obtained. As will be described later, the heat-shrinkable plastic member 40 is produced by stretching a cylindrical heat-shrinkable plastic member 40a together with the preform 10a.

  The heat-shrinkable plastic member 40 is attached to the outer surface of the container body 10 without being bonded, and is in close contact with the container body 10 so as not to move or rotate. The heat-shrinkable plastic member 40 is thinly stretched on the outer surface of the container body 10 to cover the container body 10. As shown in FIG. 2, the heat-shrinkable plastic member 40 is provided over the entire circumferential direction so as to surround the container body 10 and has a substantially circular horizontal cross section.

  In this case, the heat-shrinkable plastic member 40 is provided so as to cover the neck portion 13, the shoulder portion 12, the trunk portion 20, and the bottom portion 30 except for the mouth portion 11 in the container body 10. Thereby, desired functions and characteristics can be imparted to the neck portion 13, the shoulder portion 12, the trunk portion 20, and the bottom portion 30 of the container body 10. In FIG. 1, the heat-shrinkable plastic member 40 is crimped at a position covering the bottom 30 of the container body 10. Specifically, thermocompression bonding is performed so that the first piece 47a and the second piece 47b (FIG. 4) of the heat-shrinkable plastic member 40a of the composite preform 70 described later are overlapped. Thereby, the opening 48d (FIGS. 3 and 4) of the heat-shrinkable plastic member 40a is closed after blow molding, and the bottom portion 30 is completely covered by the heat-shrinkable plastic member 40.

  Since the heat-shrinkable plastic member 40 is not welded or bonded to the container body 10, it can be peeled off from the container body 10 and removed. Specifically, for example, the heat-shrinkable plastic member 40 is cut using a blade or the like, or a cutting line or notch (not shown) is provided in advance in the heat-shrinkable plastic member 40, and the cutting line or notch is used. The heat-shrinkable plastic member 40 can be peeled off. Thereby, the heat-shrinkable plastic member 40 can be separated and removed from the container body 10.

  The thickness of the heat-shrinkable plastic member 40 is not limited to this, but can be set to, for example, about 5 μm or more and 500 μm or less when attached to the container body 10.

  In the present embodiment, the heat-shrinkable plastic member 40 may be colored in a visible light color such as red, blue, yellow, green, brown, black, or white. The heat-shrinkable plastic member 40 may be (semi) transparent or opaque. In this case, for example, the heat-shrinkable plastic member 40 may be colored with visible light, and the container body 10 may be colorless and transparent. Alternatively, both the container body 10 and the heat-shrinkable plastic member 40 may be colored visible light. In the case where the heat-shrinkable plastic member 40 colored in the visible light color is produced, a visible-light color pigment is added to the molding material in the step of producing the heat-shrinkable plastic member 40a before blow molding by extrusion molding or the like. May be added.

(Composition of composite preform)
Next, the structure of the composite preform according to this embodiment will be described with reference to FIG.

  As shown in FIG. 3, the composite preform 70 includes a preform 10a made of a plastic material and a substantially cylindrical heat-shrinkable plastic member 40a provided so as to surround the outside of the preform 10a. .

  Among these, the preform 10a includes a mouth portion 11a, a body portion 20a connected to the mouth portion 11a, and a bottom portion 30a connected to the body portion 20a. The mouth part 11 a corresponds to the mouth part 11 of the container body 10 described above, and has substantially the same shape as the mouth part 11. Moreover, the trunk | drum 20a respond | corresponds to the neck part 13, the shoulder part 12, and the trunk | drum 20 of the container main body 10 mentioned above, and has a substantially cylindrical shape. The bottom 30a corresponds to the bottom 30 of the container body 10 described above, and has a substantially hemispherical shape.

  The heat-shrinkable plastic member 40a is attached to the outer surface of the preform 10a without being bonded, and is in close contact with the preform 10a so that it does not move or rotate, or does not fall off due to its own weight. Has been. The heat-shrinkable plastic member 40a is provided over the entire circumferential direction so as to surround the preform 10a, and has a circular horizontal cross section.

  In this case, the heat-shrinkable plastic member 40a is provided so as to cover the mouth portion 11a and the entire area excluding the lower surface 30b of the bottom portion 30a. Further, the heat-shrinkable plastic member 40a may be colored in a visible light color such as red, blue, yellow, green, brown, black, and white.

  The heat-shrinkable plastic member 40a has a large diameter part 48a and a reduced diameter part 48b having a smaller diameter than the large diameter part 48a. A transition portion 48c is interposed between the large diameter portion 48a and the reduced diameter portion 48b.

  The large diameter portion 48a is substantially cylindrical and covers the entire region of the body portion 20a of the preform 10a. However, the present invention is not limited thereto, and the large-diameter portion 48a may cover a part of the trunk portion 20a, for example, a region other than the region 13a corresponding to the neck portion 13.

  The reduced diameter portion 48b is substantially cylindrical as a whole, and extends from the bottom portion 30a of the preform 10a toward the outside (opposite side of the mouth portion 11a). An opening 48d is formed in a region surrounded by the reduced diameter portion 48b. From the opening 48d, the lower surface 30b of the bottom 30a is exposed outward. Further, the reduced diameter portion 48b is formed by contraction so that the diameter of the heat shrinkable plastic member 40a is smaller than that of the large diameter portion 48a by heat shrinking. The length L1 of the reduced diameter portion 48b may be, for example, 30% or more and 100% or less of the diameter D1 of the large diameter portion 48a. Further, the diameter D2 of the reduced diameter portion 48b may be, for example, 30% to 90% of the diameter D1 of the large diameter portion 48a.

  The transition part 48c is connected to the large diameter part 48a and the reduced diameter part 48b. The transition portion 48c is formed along the bottom portion 30a of the preform 10a. That is, the transition portion 48c corresponds to the shape of the bottom portion 30a, and in this case, constitutes a part of a spherical surface. Further, the horizontal cross section of the transition portion 48c is substantially circular, and its diameter gradually decreases from the large diameter portion 48a toward the reduced diameter portion 48b.

  FIG. 4 is a perspective view showing a portion around the bottom 30a of the heat-shrinkable plastic member 40a. As shown in FIG. 4, the reduced diameter portion 48b is formed with a first cut portion 49a and a second cut portion 49b, respectively. The first cut portion 49a and the second cut portion 49b are provided at positions facing each other in the radial direction of the reduced diameter portion 48b. The first cut portion 49a and the second cut portion 49b are each formed linearly in the longitudinal direction of the preform 10a along the wall surface of the reduced diameter portion 48b. The length L2 of the first cut portion 49a and the second cut portion 49b (the length along the longitudinal direction of the preform 10a) L2 is, for example, not less than 3 mm and not more than 20 mm, and does not reach the bottom portion 30a of the preform 10a. It has become.

  The reduced diameter portion 48b is formed with a first piece 47a and a second piece 47b separated from each other by the first cut portion 49a and the second cut portion 49b. The first piece 47a and the second piece 47b each have a substantially semicircular arc shape when viewed from the bottom surface direction, and face each other across the opening 48d.

  Thus, when the composite preform 70 is blow-molded by forming the first cut portion 49a and the second cut portion 49b at the mutually opposing positions of the reduced diameter portion 48b, the first piece 47a and the second piece 47a The pieces 47b fall in a direction approaching each other. As a result, there is no gap between the heat-shrinkable plastic member 40a and the bottom portion 30a of the preform 10a, so that the bottom portion 30 of the container body 10 and the heat-shrinkable plastic member 40 cover substantially uniformly after blow molding. Is called. For this reason, there is no possibility that the appearance, the light shielding property, and the gas barrier property of the heat-shrinkable plastic member 40 in the bottom portion 30 are deteriorated. Further, it prevents a problem that a gap is generated between the bottom 30 and the heat-shrinkable plastic member 40 due to air remaining between the bottom 30 of the container body 10 and the heat-shrinkable plastic member 40. The appearance can be prevented from deteriorating.

(Configuration of heat-shrinkable plastic member)
FIG. 5 is a perspective view showing the heat-shrinkable plastic member 40a before heat-shrinking (before being attached to the preform 10a).

  As shown in FIG. 5, the heat-shrinkable plastic member 40 a is substantially cylindrical as a whole, and has a body portion 41, and one end 41 a and the other end 41 b formed at both ends in the longitudinal direction of the body portion 41. doing. One end 41a of the body portion 41 is an end portion facing the mouth portion 11a side when the heat-shrinkable plastic member 40a is attached to the preform 10a, and the other end 41b of the body portion 41 is an end portion facing the bottom portion 30a. It is.

  In this case, a first cut portion 49a and a second cut portion 49b are formed at positions of the one end 41a of the heat-shrinkable plastic member 40a facing each other. The first cut portion 49a and the second cut portion 49b are each formed linearly in the longitudinal direction of the body portion 41, and each end from the one end 41a of the body portion 41 in the longitudinal direction of the body portion 41. . In addition, a first piece 47a and a second piece 47b separated from each other by the first cut portion 49a and the second cut portion 49b are formed at one end 41a of the heat shrinkable plastic member 40a. ing. In addition, the length L3 of the 1st cut part 49a and the 2nd cut part 49b before heat contraction is 5 mm or more and 20 mm or less, for example.

  As such a heat-shrinkable plastic member 40a, a member having an action of heat-shrinking the preform 10a is used. That is, as the heat-shrinkable plastic member (outer contraction member) 40a, for example, a member that contracts with respect to the preform 10a when heat is applied is used.

  Examples of the heat-shrinkable plastic member 40a include polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, poly-4-methylpentene-1, polystyrene, AS resin, ABS tree, polyvinyl chloride, polyvinylidene chloride, poly Vinyl acetate, polyvinyl alcohol, polyvinyl acetal, polyvinyl butyral, diallyl phthalate resin, fluororesin, polymethyl methacrylate, polyacrylic acid, polymethyl acrylate, polyacrylonitrile, polyacrylamide, polybutadiene, polybutene-1, polyisoprene, Polychloroprene, ethylene propylene rubber, butyl rubber, nitrile rubber, acrylic rubber, silicone rubber, fluorine rubber, nylon 6, nylon 6,6, nylon MXD6, aromatic Polyamide, polycarbonate, ethylene polyterephthalate, polybutylene terephthalate, ethylene polynaphthalate, U polymer, liquid crystal polymer, modified polyphenylene ether, polyether ketone, polyether ether ketone, unsaturated polyester, alkyd resin, polyimide, polysulfone, polyphenylene Examples thereof include sulfide, polyethersulfone, silicone resin, polyurethane, phenol resin, urea resin, polyethylene oxide, polypropylene oxide, polyacetal, and epoxy resin. Among these, it is preferable to use thermoplastic inelastic resins such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and polyethylene naphthalate (PEN). Moreover, those blend materials, multilayer structures, and partial multilayer structures may be used. Furthermore, various additives other than the main component resin may be added to the material of the heat-shrinkable plastic member 40a as long as the characteristics are not impaired. Examples of additives include plasticizers, UV stabilizers, anti-coloring agents, matting agents, deodorants, flame retardants, weathering agents, antistatic agents, yarn friction reducing agents, slip agents, mold release agents, An oxidizing agent, an ion exchange agent, a coloring pigment, and the like can be added. Moreover, by mixing an inert gas (nitrogen gas, argon gas) with a thermoplastic resin melt, a foam member having a foam cell diameter of 0.5 μm or more and 100 μm or less is used, and this foam preform is molded. Therefore, the light shielding property can be improved.

  The heat-shrinkable plastic member 40a may be made of the same material as the container body 10 (preform 10a). In this case, for example, the heat-shrinkable plastic member 40 can be arranged mainly in a portion of the composite container 10A where it is desired to increase the strength, and the strength of the portion can be selectively increased. Examples of such materials include thermoplastic resins, particularly PE (polyethylene), PP (polypropylene), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), and PC (polycarbonate).

  The heat-shrinkable plastic member 40a may be made of a material having a gas barrier property such as an oxygen barrier property or a water vapor barrier property. In this case, without using a multi-layer preform or a preform containing a blend material as the preform 10a, the gas barrier property of the composite container 10A is improved, oxygen is prevented from entering the container, and the content liquid is prevented from deteriorating. In addition, it is possible to prevent the evaporation of water vapor from the inside of the container to the outside and to prevent the internal volume from decreasing. Examples of such materials include PE (polyethylene), PP (polypropylene), MXD-6 (nylon), PGA (polyglycolic acid), EVOH (ethylene vinyl alcohol copolymer), and oxygen such as fatty acid salts in these materials. It is also possible to mix an absorbent material.

  The heat-shrinkable plastic member 40a may be made of a material having a light barrier property such as ultraviolet rays. In this case, the light barrier property of the composite container 10A can be improved and the content liquid can be prevented from being deteriorated by ultraviolet rays or the like without using a multilayer preform or a preform containing a blend material as the preform 10a. As such a material, a blend material or a material obtained by adding a light-shielding resin to PET, PE, or PP can be considered. Moreover, you may use the foaming member with the foam cell diameter of 0.5 micrometer or more and 100 micrometers or less produced by mixing inert gas (nitrogen gas, argon gas) with the melt of a thermoplastic resin.

  The heat-shrinkable plastic member 40a may be made of a material having a higher cold insulation property (a material having a 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. Thereby, the cool property of 10 A of composite containers is improved. Further, when the user grips the composite container 10A, it is prevented that the composite container 10A becomes difficult to hold due to being too cold. Examples of such materials include foamed polyurethane, polystyrene, PE (polyethylene), PP (polypropylene), phenol resin, polyvinyl chloride, urea resin, silicone, polyimide, melamine resin, and the like. It is preferable to mix hollow particles with a resin material containing these resins. The average particle diameter of the hollow particles is preferably 1 μm or more and 200 μm or less, and more preferably 5 μm or more and 80 μm or less. The “average particle size” means the volume average particle size and is measured by a known method using a particle size distribution / particle size distribution measuring device (for example, Nanotrack particle size distribution measuring device, manufactured by Nikkiso Co., Ltd.). can do. The hollow particles may be organic hollow particles composed of a resin or the like, or may be inorganic hollow particles composed of glass or the like. Hollow particles are preferred. Examples of the resin constituting the organic hollow particles include styrene resins such as cross-linked styrene-acrylic resins, (meth) acrylic resins such as acrylonitrile-acrylic resins, phenolic resins, fluorine resins, polyamide resins, and polyimides. Resin, polycarbonate resin, polyether resin and the like. Also, Ropeke HP-1055, Ropeke HP-91, Ropeke OP-84J, Ropeke Ultra, Ropeke SE, Ropeke ST (manufactured by Rohm and Haas), Nipol MH-5055 (manufactured by Nippon Zeon), SX8782 Commercially available hollow particles such as SX866 (manufactured by JSR Corporation) can also be used. The content of the hollow particles is preferably 0.01 parts by weight or more and 50 parts by weight or less, and preferably 1 part by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the resin material contained in the heat-shrinkable plastic member 40a. It is more preferable that the amount is not more than parts.

  The heat-shrinkable plastic member 40a may be made of a material that is less slippery than the plastic material that forms the container body 10 (preform 10a). In this case, the user can easily hold the composite container 10 </ b> A without changing the material of the container body 10.

  This heat-shrinkable plastic member 40a may be preliminarily printed with design or printing. In this case, the printing may be formed by designing or printing the plain heat-shrinkable plastic member 40a by a printing method such as an inkjet method or a gravure printing method. This printing may be performed on the heat-shrinkable plastic member 40a before being attached to the preform 10a, or may be performed with the heat-shrinkable plastic member 40a provided on the outside of the preform 10a. good. The heat-shrinkable plastic member 40a may be colored in colors such as red, blue, yellow, green, brown, black, white, and may be transparent or opaque.

(Production method of composite preform)
Next, a method for manufacturing the composite preform 70 according to this embodiment will be described with reference to FIGS.

  First, a preform 10a made of a plastic material is prepared (see FIG. 6A). In this case, for example, the preform 10a is produced by an injection molding method using an injection molding machine (not shown). The preform 10a has a mouth part 11a, a cylindrical body part 20a, and a substantially hemispherical bottom part 30a.

  Next, a substantially cylindrical heat-shrinkable plastic member 40a having one end 41a and the other end 41b is prepared (FIG. 5). A first cut portion 49a and a second cut portion 49b are formed at positions of the one end 41a of the heat-shrinkable plastic member 40a facing each other.

  Subsequently, a heat-shrinkable plastic member (outer contraction member) 40a is provided (loosely inserted) outside the preform 10a (see FIG. 6B). In this case, the heat-shrinkable plastic member 40a is loosely inserted into the preform 10a from the other end 41b side. After being loosely inserted into the preform 10a, the heat-shrinkable plastic member 40a is mounted so as to cover the entire region of the body portion 20a and the entire bottom portion 30a of the preform 10a when viewed from the side. Further, one end 41a of the heat-shrinkable plastic member 40a protrudes outside the bottom portion 30a of the preform 10a (opposite the mouth portion 11a).

  Next, the preform 10a and the heat-shrinkable plastic member 40a are heated by the heating device 55 (see FIG. 6C). At this time, the preform 10a and the heat-shrinkable plastic member 40a are uniformly heated in the circumferential direction by the heating device 55 while rotating with the mouth portion 11a facing downward. The heating temperature of the preform 10a and the heat-shrinkable plastic member 40a in this heating step may be, for example, 90 ° C. to 130 ° C.

  As described above, the heat-shrinkable plastic member 40a is heated, so that the heat-shrinkable plastic member 40a is thermally shrunk and is in close contact with the outside of the preform 10a (see FIG. 6C). At this time, the heat-shrinkable plastic member 40a is in close contact with the preform 10a so as to be along the trunk portion 20a and the bottom portion 30a, thereby forming a large diameter portion 48a and a transition portion 48c. On the other hand, the portion of the heat-shrinkable plastic member 40a that protrudes outside the bottom portion 30a of the preform 10a contracts radially inward to form a reduced diameter portion 48b. At this time, a first piece 47a and a second piece 47b separated from each other by the first cut portion 49a and the second cut portion 49b are formed in the reduced diameter portion 48b (see FIG. 4).

  Thus, by providing the heat-shrinkable plastic member 40a on the outside of the preform 10a, the composite preform having the preform 10a and the heat-shrinkable plastic member 40a in close contact with the outside of the preform 10a. 70 is obtained (see FIG. 6C).

  In this way, a series of steps for producing the composite preform 70 by previously bringing the heat-shrinkable plastic member 40a into close contact with the outside of the preform 10a and producing the composite preform 70 (FIG. 6A). To (c)) and a series of steps (FIGS. 6D to 6G) for producing a composite container 10A to be described later by blow molding can be carried out at different places (factories, etc.).

  In the above description, the case where the heat-shrinkable plastic member 40a in which the first cut portion 49a and the second cut portion 49b are formed in advance is attached to the preform 10a has been described as an example. However, the present invention is not limited thereto, and the first cut portion 49a and the second cut portion 49b may be formed after the heat-shrinkable plastic member 40a is attached to the preform 10a.

  In this case, first, the preform 10a is prepared in the same manner as described above. Next, a heat-shrinkable plastic member 40a in which the first cut portion 49a and the second cut portion 49b are not formed is prepared. Next, the heat-shrinkable plastic member 40a is loosely inserted into the preform 10a, and then the heat-shrinkable plastic member 40a is thermally shrunk so that the heat-shrinkable plastic member 40a is placed outside the preform 10a. Adhere closely. Then, the 1st notch part 49a and the 2nd notch part 49b are each formed in the position where the one end 41a of the open side of the heat-shrinkable plastic member 40a mutually opposes. Thereby, the composite preform 70 is obtained (see FIG. 3).

(Production method of composite container)
Next, a manufacturing method (blow molding method) of the composite container 10A according to the present embodiment will be described with reference to FIGS.

  For example, the composite preform 70 is produced by the above-described steps (see FIGS. 6A to 6C). Next, the composite preform 70 is heated by the heating device 51 (see FIG. 6D). At this time, the composite preform 70 is evenly heated 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 and the heat-shrinkable plastic member 40a in this heating step may be, for example, 90 ° C. to 130 ° C.

  Subsequently, the composite preform 70 heated by the heating device 51 is sent to the blow mold 50 (see FIG. 6E).

  The composite container 10 </ b> A is molded using this blow molding die 50. In this case, the blow mold 50 includes a pair of body molds 50a and 50b and a bottom mold 50c that are divided from each other (see FIG. 6E). In FIG. 6 (e), the pair of body molds 50a and 50b are open to each other, and the bottom mold 50c is raised upward. In this state, the composite preform 70 is inserted between the pair of body molds 50a and 50b.

  Next, as shown in FIG. 6 (f), after the bottom mold 50c is lowered, the pair of body molds 50a, 50b is closed and sealed by the pair of body molds 50a, 50b and the bottom mold 50c. A blow mold 50 is formed. Next, air is press-fitted into the preform 10 a and biaxial stretch blow molding is performed on the composite preform 70.

  As a result, the container body 10 is obtained from the preform 10 a in the blow molding die 50. During this time, the body molds 50a and 50b are heated to 30 ° C. to 80 ° C., and the bottom mold 50c is cooled to 5 ° C. to 25 ° C. At this time, in the blow mold 50, the preform 10a of the composite preform 70 and the heat-shrinkable plastic member 40a are expanded as a unit. Thus, the preform 10a and the heat-shrinkable plastic member 40a are integrally formed into a shape corresponding to the inner surface of the blow molding die 50.

  In this manner, a composite container 10A including the container body 10 and the heat-shrinkable plastic member 40 provided on the outer surface of the container body 10 is obtained. At this time, the first piece 47a and the second piece 47b (FIG. 4) formed in the reduced diameter portion 48b of the heat-shrinkable plastic member 40a fall down in a direction approaching each other. As a result, the heat-shrinkable plastic member 40 a is pressure-bonded at a position covering the bottom 30 of the container body 10. At this time, there is no gap between the heat-shrinkable plastic member 40a and the bottom portion 30a of the preform 10a, so that the bottom portion 30 of the container body 10 is substantially uniformly covered with the heat-shrinkable plastic member 40 and There is no possibility that the appearance of the heat-shrinkable plastic member 40 will deteriorate. Further, since air does not easily accumulate between the bottom 30 of the container body 10 and the heat-shrinkable plastic member 40, it is possible to prevent a gap from being generated between the heat-shrinkable plastic member 40 and the bottom 30. .

  Next, as shown in FIG. 6 (g), the pair of body molds 50 a and 50 b and the bottom mold 50 c are separated from each other, and the composite container 10 </ b> A is taken out from the blow molding mold 50.

  As described above, according to the present embodiment, the first cut portion 49a and the second cut portion 49b are formed at positions facing each other of the reduced diameter portion 48b of the heat-shrinkable plastic member 40a. Accordingly, when the composite preform 70 is blow-molded, the reduced diameter portion 48b is deformed so that the first piece 47a and the second piece 47b are narrowed. Therefore, the bottom portion 30 of the container body 10 and the heat-shrinkable plastic after the blow molding are performed. The product member 40 can be brought into close contact with each other, and the appearance, light-shielding property, and gas barrier property at the bottom 30 can be improved. Moreover, it can prevent that air remains between the bottom part 30 of the container main body 10, and the member 40 made from a heat-shrinkable plastic, and can prevent the malfunction which an external appearance deteriorates. As a result, the composite container 10A provided with various functions and characteristics such as light shielding properties and gas barrier properties can be manufactured with high quality.

  Furthermore, according to the present embodiment, when producing the composite container 10A, a general blow molding apparatus can be used as it is, so that it is necessary to prepare a new molding facility for producing the composite container 10A. Absent. Further, since the heat-shrinkable plastic member 40a is provided outside the preform 10a, it is not necessary to prepare a new molding equipment for molding the preform 10a.

(Modification)
Next, a modified example of the composite preform 70 according to the present embodiment will be described with reference to FIG. The modification shown in FIG. 7 is different in that a part of the first piece 47a and a part of the second piece 47b are crimped to each other, and other configurations are the same as those in FIGS. 1 to 6 described above. This is substantially the same as the embodiment shown. 7, the same parts as those in FIGS. 1 to 6 are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 7, in the composite preform 70, the reduced diameter portion 48b is formed with a first piece 47a and a second piece 47b separated from each other by the first cut portion 49a and the second cut portion 49b. Yes.

  In this case, a part of the first piece 47a and a part of the second piece 47b are pressure-bonded to each other. Specifically, in the first piece 47a, the first pressure-bonding portion 47c located approximately in the middle between the first cut portion 49a and the second cut portion 49b, and the first cut portion 49a and the second piece in the second piece 47b. The second pressure-bonding portion 47d located approximately in the middle of the notch 49b is thermocompression bonded to each other. As a result, the first pressure-bonding portion 47c and the second pressure-bonding portion 47d are connected to each other, and the first piece 47a and the second piece 47b are integrated. The first piece 47a and the second piece 47b are each formed in a w shape or a ω shape as viewed from the bottom surface direction.

  When producing such a composite preform 70, after the step of heat-shrinking the heat-shrinkable plastic member 40a (FIG. 6C), the step of heating the composite preform 70 by the heating device 51 (FIG. Before d)), a step of crimping a part of the first piece 47a and a part of the second piece 47b to each other is provided. Specifically, the heat-shrinkable plastic member 40a immediately after the heat-shrinking step (FIG. 6C) is in a high temperature state using a tool for thermocompression bonding (not shown) or the like. The first crimping portion 47c and the second crimping portion 47d are crimped by sandwiching the first crimping portion 47c of 47a and the second crimping portion 47d of the second piece 47b inward (see the arrow in FIG. 7). . Alternatively, after the heat-shrinkable plastic member 40a is cooled, it may be melt-bonded using a heated tool (not shown) or the like. Further, after the heat-shrinkable plastic member 40a has cooled, a tool (not shown) or the like may be ultrasonically vibrated and heat generated by vibration may be used for melt-compression bonding.

  As described above, when the composite preform 70 shown in FIG. 7 is used, when the composite preform 70 is blow-molded, the reduced diameter portion 48b is deformed so that the first piece 47a and the second piece 47b are narrowed. After the blow molding, the bottom 30 of the container body 10 and the heat-shrinkable plastic member 40 are in close contact with each other, and the appearance at the bottom 30 can be improved. At the same time, since air is discharged from the opening 48d in the blow molding process, it is more effectively prevented that air remains between the bottom 30 of the container body 10 and the heat-shrinkable plastic member 40. be able to. Further, since a part of the first piece 47a and a part of the second piece 47b are pressure-bonded to each other, the bottom portion 30 of the container body 10 and the heat-shrinkable plastic member 40 can be more reliably adhered. The composite container 10A having a good appearance and excellent light-shielding property can be manufactured with high quality.

DESCRIPTION OF SYMBOLS 10 Container main body 10A Composite container 10a Preform 11, 11a Mouth part 12 Shoulder part 13 Neck part 14 Screw part 17 Flange part 20, 20a Body part 30, 30a Bottom part 40a Heat-shrinkable plastic member 47a 1st piece 47b 2nd piece 48a Large diameter portion 48b Reduced diameter portion 48c Transition portion 48d Opening 49a First cut portion 49b Second cut portion 70 Composite preform

Claims (8)

In the method for producing a composite preform,
Preparing a preform made of a plastic material having a mouth portion, a trunk portion, and a bottom portion;
A cylindrical heat-shrinkable plastic member having one end and the other end, wherein a first cut portion and a second cut portion are formed at opposite positions of the one end, respectively. A step of preparing a manufacturing member;
Loosely inserting the heat-shrinkable plastic member into the preform from the other end side;
A method of manufacturing a composite preform, comprising: heat-shrinking the heat-shrinkable plastic member to bring the heat-shrinkable plastic member into close contact with the outside of the preform. In the method for producing a composite preform,
Preparing a preform made of a plastic material having a mouth portion, a trunk portion, and a bottom portion;
Preparing a heat-shrinkable plastic member;
Loosely inserting the heat-shrinkable plastic member into the preform;
Heat-shrinking the heat-shrinkable plastic member to closely adhere the heat-shrinkable plastic member to the outside of the preform;
A method for manufacturing a composite preform, comprising: forming a first cut portion and a second cut portion at positions opposite to each other at one end on the open side of the heat-shrinkable plastic member. A first piece and a second piece separated from each other by the first cut portion and the second cut portion are formed at the one end of the heat-shrinkable plastic member,
The step of crimping the part of the first piece and the part of the second piece to each other is provided after the step of heat-shrinking the heat-shrinkable plastic member. 3. A method for producing a composite preform according to 2. In the manufacturing method of the composite container,
A step of producing a composite preform by the method of manufacturing a composite preform according to any one of claims 1 to 3,
A step of blow-molding the preform and the heat-shrinkable plastic member of the composite preform to inflate the preform and the heat-shrinkable plastic member together. A method for producing a composite container. In composite preform,
A preform made of a plastic material having a mouth, a body, and a bottom;
A cylindrical heat-shrinkable plastic member provided so as to surround the outside of the preform,
The heat-shrinkable plastic member has a cylindrical large-diameter portion that covers at least the body portion of the preform, and a reduced-diameter portion that extends outward from the bottom portion of the preform,
A composite preform, wherein a first cut portion and a second cut portion are formed at positions of the reduced diameter portion facing each other.   The reduced diameter portion includes a first piece and a second piece separated from each other by the first cut portion and the second cut portion, and a part of the first piece and a part of the second piece. The composite preform according to claim 5, wherein and are pressure-bonded to each other. A composite container which is a blow molded product of the composite preform according to claim 5 or 6,
A container body having a mouth portion, a trunk portion, and a bottom portion;
A heat-shrinkable plastic member provided in close contact with the outside of the container body,
The composite container, wherein the heat-shrinkable plastic member is crimped at a position covering the bottom of the container body. A heat-shrinkable plastic member mounted so as to surround the outside of the preform,
A cylindrical main body having one end and the other end;
A heat-shrinkable plastic member, characterized in that a first cut portion and a second cut portion are formed at opposite positions of the one end.

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