JP2020097228A - Method for manufacturing plastic member and method for manufacturing composite container - Google Patents

Abstract

To provide a method for manufacturing a plastic member and a method for manufacturing a composite container that enable various functions and characteristics to be imparted to a container.SOLUTION: The method of manufacturing a plastic member 40 of the present invention is for manufacturing a composite container 10A having a preform and the plastic member 40 adhered to the outside of the preform by being mounted around the outside of the preform and heated together with the preform as an integral part, and the present invention is characterized in that the plastic member 40 is a heat-shrinkable tube, comprising: (1) heating and melting a resin material comprising a cross-linkable resin; (2) extruding the heat-melted resin material to obtain an extruded product; (3) expanding the extruded product; and (4) irradiating the expanded extruded product with an active light beam to cross-link the cross-linkable resin.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method for manufacturing a plastic member and a method for manufacturing a composite container.

In recent years, plastic bottles have become common as a container for storing a liquid content such as food and drink, and the liquid content is stored in such a plastic bottle.

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 containing a single-layer material such as PET or PP, a multi-layer material, a blend material, or the like is used to form a container shape. However, in the conventional biaxial stretch blow molding method, it is general that the preform is simply molded into a container shape. Therefore, when the container has various functions and characteristics (barrier property, heat retaining property, etc.), its means is limited, for example, by changing the material forming the preform. In particular, it is difficult to provide different functions and characteristics depending on the part of the container (for example, the body or the bottom).

JP, 2009-241526, A

The present invention has been made in view of the above points, and provides a method for manufacturing a plastic member and a method for manufacturing a composite container, which are capable of imparting various functions and characteristics to the container. With the goal.

The method for manufacturing a plastic member of the present invention is
A plastic member for manufacturing a composite container having a preform and a plastic member adhered to the outside of the preform by being mounted so as to surround the outside of the preform and being heated integrally with the preform. The manufacturing method of
(1) A step of heating and melting a resin material containing a crosslinkable resin,
(2) A step of extruding the resin material that is heated and melted to obtain an extruded product,
(3) A step of expanding the diameter of the extruded product,
(4) irradiating the extruded product having the expanded diameter with an actinic ray to crosslink the crosslinkable resin,
The plastic member is a heat-shrinkable tube.

In the aspect of the present invention, the resin material preferably comprises a crosslinking agent and/or a crosslinking aid.

In the aspect of the present invention, the actinic ray is preferably an electron beam.

In the aspect of the present invention, the electron beam dose is preferably 1 to 1000 kGy.

The method for manufacturing the composite container of the present invention is
A step of preparing a preform made of a plastic material,
On the outside of the preform, a step of providing a plastic member obtained by the above method,
Heating the preform and the plastic member and inserting them into a blow mold,
Blow-molding the preform and the plastic member in the blow molding die to expand the preform and the plastic member integrally.

According to the present invention, a plastic member capable of imparting various functions and characteristics to a composite container can be obtained by appropriately selecting the type and shape of the plastic member.
In addition, since the plastic member obtained by the method of the present invention is a heat-shrinkable tube, after blow molding, less air enters between the container body and the plastic member, and adhesion can be improved.
Furthermore, since the plastic member obtained by the method of the present invention contains a crosslinkable resin crosslinked by actinic rays, the scratch resistance and heat resistance of the composite container can be improved.
In addition, since the slip agent used during transportation on the production line is an alkaline chemical, a normal PET bottle or the like is decomposed, and there is a risk that the tint may change or be damaged. Since the plastic member included in the composite container obtained by the method according to the present invention has high chemical resistance, such a problem can be solved.

FIG. 1 is a partial vertical sectional view showing a composite container according to a first embodiment of the present invention. FIG. 2 is a horizontal sectional view showing a composite container according to the first embodiment of the present invention (a sectional view taken along line II-II in FIG. 1). FIG. 3 is a vertical sectional view showing a composite preform according to the first embodiment of the present invention. FIG. 4 is a perspective view showing a plastic member. FIGS. 5A to 5F are schematic views showing the blow molding method according to the first embodiment of the present invention. FIGS. 6A to 6F are schematic views showing a blow molding method according to a modified example of the first embodiment of the present invention. FIG. 7 is a partial vertical sectional view showing a composite container according to the second embodiment of the present invention. FIG. 8 is a horizontal cross-sectional view (cross-sectional view taken along line XIII-XIII in FIG. 7) showing the composite container according to the second embodiment of the present invention. FIG. 9 is a vertical sectional view showing a composite preform according to a second embodiment of the present invention. FIG. 10 is a perspective view showing the inner label member and the plastic member. 11A to 11F are schematic views showing the blow molding method according to the second embodiment of the present invention. 12A to 12G are schematic views showing a blow molding method according to a modified example of the second embodiment of the present invention.

First Embodiment Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. 1 to 6 are views showing a first embodiment of the present invention.

First, an outline of a composite container manufactured by the blow molding method according to the present embodiment will be described with reference to FIGS. 1 and 2. In addition, in this specification, "upper" and "lower" mean the upper side and the lower side in a state (FIG. 1) in which the composite container 10A is upright, respectively.

The composite container 10A shown in FIGS. 1 and 2 is biaxially stretched with respect to a composite preform 70 (see FIG. 3) including the preform 10a and the plastic member 40a using a blow molding die 50, as described later. It is obtained by expanding the preform 10a of the composite preform 70 and the plastic member 40a as one body by performing blow molding.

Such a composite container 10A includes a container body 10 made of a plastic material located inside, and a plastic member 40 provided in close contact with the outside of the container body 10.

Of 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, and a body portion 20 provided below the shoulder portion 12, And a bottom portion 30 provided below the body portion 20.

On the other hand, the plastic member 40 is closely attached to the outer surface of the container body 10 in a thinly extended state, and is attached to the container body 10 in a state where it does not easily move or rotate, or does not fall by its own weight. It is closely attached to the degree.

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 body portion 20, and the bottom portion 30.

Of these, the mouth portion 11 has a screw portion 14 screwed to 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 portion 12 is located between the neck portion 13 and the body portion 20, and has a shape in which the diameter gradually increases from the neck portion 13 side toward the body portion 20 side.

Further, the body portion 20 has a cylindrical shape having 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 tubular shape such as a quadrangular tubular shape or an octagonal tubular shape. Alternatively, the body portion 20 may have a tubular shape having a horizontal cross section that is not uniform from the upper side to the lower side. Further, in the present embodiment, the body portion 20 has no unevenness and has a substantially flat surface, but the present invention is not limited to this. For example, the body portion 20 may be formed with unevenness such as a panel or a groove.

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

The thickness of the container body 10 in the body portion 20 is not limited to this, but can be reduced to, for example, about 50 μm to 250 μm. Further, the weight of the container body 10 is not limited to this, but may be 10 g to 20 g when the content volume of the container body 10 is 500 ml, for example. By reducing the thickness of the container body 10 in this manner, the weight of the container body 10 can be reduced.

Such a container body 10 can be manufactured by subjecting a preform 10a (described later) manufactured by injection molding of a synthetic resin material to biaxial stretch blow molding. 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. Moreover, you may blend and use the above-mentioned various resins. The container body 10 may be colored in colors such as red, blue, yellow, green, brown, black, and white, but it is preferably colorless and transparent in consideration of ease of recycling. 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 multi-layer molded bottle having two or more layers. That is, by injection molding, for example, the intermediate layer has a gas barrier property such as MXD-6 (nylon), MXD-6+ fatty acid salt, PGA (polyglycolic acid), EVOH (ethylene vinyl alcohol copolymer) or PEN (polyethylene naphthalate). Also, a preform 10a having three or more layers as a resin (intermediate layer) having a light blocking property may be injection molded and then blow molded to form a multi-layer bottle having a gas barrier property and a light blocking property. A resin obtained by blending the various resins described above may be used as the intermediate layer.

Further, by mixing an inert gas (nitrogen gas, argon gas) with the melt of the thermoplastic resin, a foamed preform having a foamed cell diameter of 0.5 to 100 μm is molded, and this foamed preform is blow molded. By doing so, the container body 10 may be manufactured. Since such a container body 10 has foam cells built therein, it is possible to enhance the light-shielding property of the entire container body 10.

Such a container body 10 may be composed of, for example, a bottle having a full volume of 100 ml to 2000 ml. Alternatively, the container body 10 may be a large bottle having a full-filled volume of, for example, 10 L to 60 L.

Next, the plastic member 40 will be described. The plastic member 40 (40a) is provided so as to surround the outside of the preform 10a as described later, and is adhered to the outside of the preform 10a, and then obtained by being biaxially stretch blow-molded together with the preform 10a. To be This plastic member 40a contains a crosslinkable resin crosslinked by actinic rays, and is a heat-shrinkable tube produced by undergoing a step of imparting heatshrinkability and having a function of shrinking with respect to the preform 10a. Is. Since the plastic member 40a is the heat-shrinkable tube, it is possible to prevent the displacement of the preform 10a from occurring. Further, the followability to blow molding can be improved. Furthermore, since the plastic member 40a contains a crosslinkable resin crosslinked by actinic rays, the transparency of the plastic member and the scratch resistance and heat resistance of the composite container can be improved. The plastic member 40a may be contractible or elastic and can be contracted without any external action.

The plastic member 40a is provided on the outer side of the preform 10a, is integrally heated with the preform 10a, and is biaxially stretch blow molded. As a result, the plastic member 40 is obtained.

The plastic member 40 is attached to the outer surface of the container body 10 without adhering to the container body 10 and is in close contact with the container body 10 so as not to move or rotate, or so close as not to drop by its own weight. The plastic member 40 is thinly stretched on the outer surface of the container body 10 to cover the container body 10. Further, as shown in FIG. 2, the plastic member 40 is provided over the entire area in the circumferential direction so as to surround the container body 10, and has a substantially circular horizontal cross section.

In this case, the plastic member 40 is provided so as to cover the shoulder portion 12 and the body portion 20 of the container body 10 excluding the mouth portion 11 and the neck portion 13. As a result, desired functions and characteristics can be given to the shoulder portion 12 and the body portion 20 of the container body 10.

The plastic member 40 may be provided in the whole or a part of the container body 10 other than the mouth 11. For example, the plastic member 40 may be provided so as to cover the neck portion 13, the shoulder portion 12, and the body portion 20 of the container body 10 except the mouth portion 11 and the bottom portion 30. Alternatively, the plastic member 40 may be provided so as to cover a part of the bottom portion 30 in addition to this. Further, the number of plastic members 40 is not limited to one, and a plurality of members may be provided. For example, two plastic members 40 may be provided on the outer surface of the neck portion 13 and the outer surface of the body portion 20, respectively.

Further, since the plastic member 40 is not welded or adhered to the container body 10, it can be separated (peeled) from the container body 10 and removed.

Examples of the method of separating (peeling) the plastic member 40 from the container body 10 include hot water separation. Specifically, since the plastic member 40 (40a) has heat shrinkability, the composite container 10A including the plastic member 40 and the container body 10 is made into a small piece-shaped container body and a small piece-shaped plastic body. By crushing into a plurality of flakes including a member and immersing the plurality of flakes in hot water, the flakes can be separated into a small-piece-shaped container body and a small-piece-shaped plastic member, respectively. Separation of the small-piece-shaped container body and the small-piece-shaped plastic member occurs due to the heat shrinkage of the plastic member 40 and the difference in their specific gravities. Moreover, the separated small-piece-shaped container body and the separated small-piece-shaped plastic member are separately collected.

As another example of the separating method, for example, the plastic member 40 is cut off by using a knife or the like, or the plastic member 40 is provided with a cutting line in advance and the plastic member 40 is peeled along the cutting line. be able to. Since the plastic member 40 can be separated and removed from the container body 10 by the above method, the colorless and transparent container body 10 can be recycled as in the conventional case.

In one embodiment, a label such as a shrink label or a stretch label can be attached to the plastic member 40 via an adhesive (not shown). Since the label is adhered to the plastic member in this manner, the plastic member can be separated (peeled) from the container body at the same time when the label is removed. The adhesive used in this case is not particularly limited as long as the plastic member is attached to the label and can be separated from the container body, but is not particularly limited, but a cyanoacrylate-based adhesive, a silicone-based adhesive, an epoxy, etc. System adhesives and the like.

Further, the thickness of the plastic member 40 is not limited to this, but may be, for example, about 5 μm to 50 μm in a state of being attached to the container body 10.

Next, the configuration of the composite preform according to the present 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 bottomless cylindrical plastic member 40a provided outside the preform 10a.

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. Of these, the mouth portion 11a corresponds to the mouth portion 11 of the container body 10 described above, and has substantially the same shape as the mouth portion 11. The body portion 20a corresponds to the neck portion 13, the shoulder portion 12 and the body portion 20 of the container body 10 described above, and has a substantially cylindrical shape. The bottom portion 30a corresponds to the bottom portion 30 of the container body 10 described above, and has a substantially hemispherical shape.

The plastic member 40a is attached to the outer surface of the preform 10a without being adhered, and is in close contact with the preform 10a such that it does not move or rotate, or in such a degree that it does not fall by its own weight. .. The plastic member 40a is provided over the entire area in the circumferential direction so as to surround the preform 10a and has a circular horizontal cross section.

In this case, the plastic member 40a is provided so as to cover the entire body portion 20a except the portion 13a corresponding to the neck portion 13 of the container body 10.

The plastic member 40a may be provided in the whole area or a partial area other than the mouth portion 11a. For example, the plastic member 40a may be provided so as to cover the entire body portion 20a including the neck portion 13. Alternatively, the plastic member 40a may cover the entire region of the body portion 20a and a partial region of the bottom portion 30a. Further, the number of the plastic member 40a is not limited to one, and a plurality of members may be provided. For example, two plastic members 40a may be provided at two locations outside the body portion 20a.

The plastic member 40a (40) is a resin material containing a crosslinkable resin that crosslinks when irradiated with an actinic ray. Examples of the crosslinkable resin include resins such as PE, PP, polystyrene, polyvinylidene fluoride, polymethyl acrylate, polyvinyl chloride, polybutadiene, natural rubber, vinyl alcohol, polyamide resin, and ethylene vinyl acetate copolymer (EVA). Can comprise. Among these, PE and PP are preferable.
The content of the crosslinkable resin in the plastic member 40a is preferably 95 to 100% by mass, and more preferably 98 to 100% by mass.

In addition to the crosslinkable resin, the resin material may be, for example, polylactic acid, poly-4-methylpentene-1, polystyrene, AS resin, ABS resin, polyvinylidene chloride, or poly(vinylidene chloride), as long as its properties are not impaired. Vinyl acetate, polyvinyl acetal, polyvinyl butyral, diallyl phthalate resin, fluororesin, polymethyl methacrylate, polyacrylic acid, polyacrylonitrile, polyacrylamide, polybutene-1, nylon 6, nylon 6,6, nylon MXD6, aromatic Polyamide, polycarbonate, ethylene polyterephthalate, butylene polyterephthalate, ethylene polynaphthaleneate, U polymer, liquid crystal polymer, modified polyphenylene ether, polyether ketone, polyether ether ketone, unsaturated polyester, alkyd resin, polyimide, polysulfone, polyphenylene It may contain sulfide, polyether sulfone, silicone resin, polyurethane, phenol resin, urea resin, polyethylene oxide, polypropylene oxide, polyacetal, epoxy resin and the like.
Further, the resin material may include a copolymer obtained by polymerizing two or more monomer units constituting the above resin. Further, the resin material may include two or more kinds of the above resins. Further, a blended material thereof, a multi-layer structure, or a partially multi-layer structure may be used.

The resin material preferably contains a cross-linking agent, and examples of the cross-linking agent include hexamethylenediamine carbamate, diortotolyl guanidine, dicumyl peroxide, and 1,3-phenylene bisoxazoline.

The content of the crosslinking agent is preferably 0.1 to 5 parts by mass, more preferably 0.1 to 2 parts by mass, when the total amount of the resin material is 100 parts by mass.

Further, the resin material preferably contains a crosslinking aid, and as the crosslinking agent, for example, triallyl isocyanurate, triallyl cyanurate, diallyl fumarate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, Examples thereof include ethylene glycol dimethacrylate.

The content of the cross-linking aid is preferably 0.1 to 5 parts by mass, and more preferably 0.1 to 2 parts by mass, when the total amount of the resin material is 100 parts by mass.

Further, the resin material may contain various additives in addition to the resin material as the main component as long as the object of the present invention is not impaired. Examples of the additive include a plasticizer, an ultraviolet stabilizer, a coloring preventing agent, a matting agent, a deodorant, a flame retardant, a weatherproofing agent, an antistatic agent, a thread friction reducing agent, a slip agent, a release agent, and an antistatic agent. Examples thereof include an oxidizing agent, an ion exchange agent, and a coloring pigment.

Further, the plastic member 40a (40) may be made of a resin material containing the same material as the preform 10a (container body 10). In this case, in the composite container 10A, for example, the plastic member 40a (40) can be arranged in a concentrated manner in a portion where the strength is desired to be increased, and the strength in that portion can be selectively increased. For example, a plastic member 40 may be provided around the shoulder 12 of the container body 10 to increase the strength of this portion. Examples of such a material include polyolefin resins such as PE and PP, polystyrene resins such as PS, and the like.

Further, the plastic member 40a may be made of a resin material containing 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 enhanced, 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 prevent the decrease of the internal volume. For example, in the container body 10, a plastic member 40 may be provided on the entire area of the shoulder portion 12, the neck portion 13 and the body portion 20 and a part of the bottom portion 30 to enhance the gas barrier property of this portion. As such a material, it is possible to mix PE, PP, MXD-6, PGA, EVOH, PEN, or an oxygen absorbent such as a fatty acid salt with these materials.

Further, the plastic member 40a may be made of a resin material containing a material having a ray barrier property against ultraviolet rays and the like. In this case, without using a multi-layer preform or a preform containing a blend material as the preform 10a, it is possible to enhance the light barrier property of the composite container 10A and prevent the content liquid from being deteriorated by ultraviolet rays or the like. For example, in the container body 10, a plastic member 40a may be provided on the entire area of the shoulder portion 12, the neck portion 13, the body portion 20 and a part of the bottom portion to enhance the ultraviolet barrier property of this portion. As such a material, a resin material containing two or more kinds of the above-mentioned resins, or a material obtained by adding a light shielding resin to PET, PE or PP is considered. Further, a foam member having a foam cell diameter of 0.5 to 100 μm, which is produced by mixing an inert gas (nitrogen gas, argon gas) with a melt of a thermoplastic resin, may be used.

In addition, the plastic member 40a may be made of a resin material containing a material having a higher heat retention property or a lower heat retention property (a material having a lower thermal conductivity) than the plastic material forming the container body 10 (preform 10a). good. 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 heat retaining property or the cold retaining property of the composite container 10A is enhanced. For example, a plastic member 40 may be provided on all or part of the body portion 20 of the container body 10 to enhance the heat retaining property or the cold retaining property of the body portion 20. Further, when the user holds the composite container 10A, it is prevented that the composite container 10A becomes difficult to hold due to being too hot or too cold. As such a material, foamed polyurethane, polystyrene, PE, PP, phenol resin, polyvinyl chloride, urea resin, silicone, polyimide, melamine resin and the like can be considered. Hollow particles are preferably mixed with a resin material containing these resins. The average particle diameter of the hollow particles is preferably 1 to 200 μm, more preferably 5 to 80 μm. The "average particle size" means a volume average particle size, and is measured by a known method using a particle size distribution/particle size distribution measuring device (for example, Nanotrac 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 a glass or the like, but the organic particles are excellent because of excellent dispersibility. Hollow particles are preferred. Examples of the resin constituting the organic hollow particles include styrene resins such as crosslinked styrene-acrylic resins, (meth)acrylic resins such as acrylonitrile-acrylic resins, phenolic resins, fluorine resins, polyamide resins, polyimides. Examples of the resin include a resin, a polycarbonate resin, and a polyether resin. In addition, low pake HP-1055, low pake HP-91, low pake OP-84J, low pake ultra, low pake SE, low pake ST (manufactured by Rohm and Haas Co., Ltd.), nipol MH-5055 (manufactured by Nippon Zeon Co., Ltd.), SX8782. It is also possible to use commercially available hollow particles such as SX866 (manufactured by JSR Corporation).
When the plastic member 40a is composed of a single layer, the content of the hollow particles is preferably 0.01 to 50 parts by mass with respect to 100 parts by mass of the resin material contained in the plastic member 40a. It is more preferably about 20 to 20 parts by mass. When the plastic member 40a is composed of multiple layers, it is preferably 0.01 to 50 parts by mass with respect to 100 parts by mass of the resin material contained in the layer of the plastic member 40a containing hollow particles. It is more preferably about 20 to 20 parts by mass.

Further, the plastic member 40a may be made of a material that is less slippery than the plastic material forming the container body 10 (preform 10a). In this case, the user can easily hold the composite container 10A without changing the material of the container body 10.
For example, a plastic member 40 may be provided on all or part of the body 20 of the container body 10 to facilitate holding the body 20.

Further, the plastic member 40a may be designed or printed. In this case, it is possible to display an image or a character on the composite container 10A without adding a label or the like to the container body 10 after the blow molding. For example, a plastic member 40 may be provided on all or part of the body 20 of the container body 10 to display images and characters on the body 20. Printing can be performed by a printing method such as an inkjet method, a gravure printing method, an offset printing method, a flexographic printing method, or the like. For example, in the case of using the inkjet method, the printing layer can be formed by applying the UV curable ink to the plastic member 40a (40), irradiating it with UV, and curing it. This printing may be performed on the plastic member 40a before being attached to the preform 10a, or may be performed with the plastic member 40a provided on the outside of the preform 10a. Furthermore, the plastic member 40 of the composite container 10A after blow molding may be printed.

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

Next, the shape of the plastic member 40a will be described.

As shown in FIGS. 3 and 4, the plastic member 40a preferably has a bottomless cylindrical shape as a whole. By providing such a plastic member 40, various functions and characteristics can be given to the body portion 20 of the composite container 10A.

In the composite container 10A shown in FIG. 1, the plastic member 40 extends from the shoulder portion 12 of the container body 10 to a lower portion of the body portion 20. Further, in the composite preform 70 shown in FIG. 3, the plastic member 40a is adhered so as to cover only the body portion 20a of the preform 10a, and more specifically, the neck portion 13 of the container body 10 of the body portion 20a. Covers a region excluding a portion 13a corresponding to the above and a portion corresponding to a lower portion of the body portion 20a. The present invention is not limited to this, and the plastic member 40 may cover a part of the bottom portion of the container body 10. Similarly, the plastic member 40a is the bottom portion 30a of the preform 10a. It may cover a part of. The same applies to the following aspects.

Next, a method of manufacturing the plastic member 40a will be described.

The plastic member 40a is
(1) A step of heating and melting a resin material containing a crosslinkable resin,
(2) a step of extruding the heat-melted resin material to obtain an extruded product,
(3) a step of expanding the diameter of the extruded product,
(4) A step of irradiating the expanded product having an increased diameter with an actinic ray to cross-link the cross-linkable resin, thereby producing the product.
Hereinafter, each step will be described in detail.

(1): Heating and Melting Step In the heating and melting step, the resin material is preferably heated to a melting point temperature (Tm) to Tm+70° C., more preferably Tm to Tm+40° C.

(2): Extrusion molding step By extruding the heat-melted resin material into a tube shape, for example, an extrusion molded article can be obtained. The multi-layered plastic member 40a can be obtained by co-extruding two or more kinds of resin materials.

(3): Diameter Expansion Step The diameter of the extrusion molded article can be expanded by a conventionally known method. For example,
First, one end of a tubular extruded product is closed by welding or bonding it.
Next, the extruded product whose one end is closed is placed in a mold whose inner diameter is larger than the outer diameter of the extruded product.
Next, a blow device is placed (mounted) on the other end of the extrusion molded product. At this time, it is preferable that the blow device is in close contact with the extruded product so that air does not leak from between them.
Then, the extruded product, the mold and the blowing device are sent to the heating furnace in this arrangement and heated inside the heating furnace. 70-150 degreeC is preferable and, as for the heating temperature at this time, 80-125 degreeC is more preferable. Further, as the heating furnace, a hot air circulation type heating furnace can be used in order to make the inside thereof have a uniform temperature. Further, these may be heated by passing the extruded product, the mold, and the blowing device through the heated liquid.
Next, the extrusion-molded product, the mold and the blow device are taken out of the heating furnace, and air is blown into the extrusion-molded product from the blow device to press and stretch the inner surface of the extrusion-molded product. As a result, the extrusion-molded product is expanded and expanded in diameter along the inner surface shape of the mold. The diameter of the extruded product may be increased while heating it in a heating furnace. In one embodiment, after the diameter expansion, the extruded product may be cooled by impregnating it in cold water while the air is ejected from the blower.

(4): Crosslinking step In the present invention, the crosslinkable resin contained in the resin material can be crosslinked by irradiating the extruded product having the expanded diameter with an actinic ray.
In the present specification, the actinic ray means radiation that chemically acts on the resin material to promote the crosslinking reaction, and specifically, visible rays, ultraviolet rays, X-rays, electron rays, α rays, It means β rays, γ rays, etc. Among these, electron beams are preferable because they are easy to control, and γ rays are preferable because they have excellent penetrating power.
Here, the electron beam and gamma ray doses are preferably 1 to 1000 kGy, and more preferably 20 to 300 kGy. Further, the acceleration voltage of the electron beam is preferably 50 to 1000 kV, and more preferably 70 to 400 kV.

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

First, a preform 10a made of a plastic material is prepared (see FIG. 5(a)). In this case, the preform 10a may be manufactured by an injection molding method using, for example, an injection molding machine (not shown).

Next, the plastic member 40a is loosely inserted on the outer side of the preform 10a (see FIG. 5B). In this case, the plastic member 40a has a bottomless cylindrical shape as a whole and has a cylindrical body portion 41. The plastic member 40a covers the entire body portion 20a except the portion corresponding to the neck portion 13 of the container body 10.

Next, the preform 10a and the plastic member 40a are heated by the heating device 51 (see FIG. 5C). As a result, the composite preform 70 having the preform 10a and the plastic member 40a adhered to the outside of the preform 10a can be manufactured. At this time, the preform 10a and the plastic member 40a are uniformly heated in the circumferential direction by the heating device 51 while rotating with the mouth 11a facing downward. The heating temperature of the preform 10a and the plastic member 40a in this heating step may be, for example, 90°C to 130°C.

As described above, by heating the plastic member 40a, the plastic member 40a is thermally contracted and adheres to the outside of the preform 10a (see FIG. 5C).

Subsequently, the composite preform 70 heated by the heating device 51 is sent to the blow molding die 50 (see FIG. 5D).

The composite container 10A is molded using this blow molding die 50. In this case, the blow molding die 50 is composed of a pair of body portion dies 50a and 50b and a bottom portion die 50c which are divided from each other (see FIG. 5D). In FIG. 5D, the pair of body dies 50a and 50b are open from each other, and the bottom die 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. 5(e), after the bottom mold 50c is lowered, the pair of body molds 50a and 50b are closed, and the pair of body molds 50a and 50b and the bottom mold 50c are used. A closed blow molding die 50 is configured. Next, air is press-fitted into the preform 10a, and the composite preform 70 is biaxially stretch blow molded.

As a result, 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 to 80°C, and the bottom die 50c is cooled to 5 to 25°C. At this time, the preform 10a of the composite preform 70 and the plastic member 40a are integrally expanded in the blow molding die 50. As a result, the preform 10a and the plastic member 40a are integrally formed into a shape corresponding to the inner surface of the blow molding die 50.

In this way, a composite container 10A including the container body 10 and the plastic member 40 provided on the outer surface of the container body 10 is obtained.

Next, as shown in FIG. 5F, the pair of body dies 50a and 50b and the bottom die 50c are separated from each other, and the composite container 10A is taken out from the blow molding die 50.

Modification of manufacturing method of composite container 10A

Next, another modification of the blow molding method (method for manufacturing the composite container 10A) according to the present embodiment will be described with reference to FIGS. The modified example shown in FIGS. 6A to 6G is to heat the preform 10a and the plastic member 40a in two stages, and the other configurations are those shown in FIGS. 5A to 5F. Is almost the same as. 6A to 6G, the same parts as those in FIGS. 5A to 5F are designated by the same reference numerals and detailed description thereof will be omitted.

First, a preform 10a made of a plastic material is prepared (see FIG. 6A).

Next, the plastic member 40a is loosely inserted on the outer side of the preform 10a (see FIG. 6B). In this case, the plastic member 40a has a bottomless cylindrical shape as a whole and has a cylindrical body portion 41. The plastic member 40 is mounted so as to cover the entire body portion 20a except the portion corresponding to the neck portion 13 of the container body 10.

Next, the preform 10a and the plastic member 40a are heated by the first heating device 55 (see FIG. 6C). At this time, the heating temperature of the preform 10a and the plastic member 40a may be, for example, 50°C to 100°C.

By heating the plastic member 40a, the plastic member 40a is heat-shrinked and adheres to the outside of the preform 10a. As a result, a composite preform 70 having the preform 10a and the plastic member 40a adhered to the outside of the preform 10a is obtained (see FIG. 6C).

In this way, a series of steps for producing the composite preform 70 by preliminarily heating and closely adhering the plastic member 40a to the outside of the preform 10a using the first heating device 55 to produce the composite preform 70 Performing the steps (FIGS. 6(a) to 6(c)) and the series of steps (FIGS. 6(d) to 6(g)) for producing the composite container 10A by blow molding at different places (factory or the like). Will be possible.

Next, the composite preform 70 is heated by the second heating device 51 (see FIG. 6D). At this time, the composite preform 70 is uniformly heated in the circumferential direction by the second heating device 51 while rotating with the mouth portion 11a facing downward. The heating temperature of the preform 10a and the plastic member 40a in this heating step may be, for example, 90°C to 130°C.

Subsequently, the composite preform 70 heated by the second heating device 51 is sent to the blow molding die 50 (see FIG. 6E). In this case, heating for shrinking the plastic member 40a and heating for blow molding the preform 10a can be performed in the same step.

The composite preform 70 is molded using this blow molding die 50, and is provided on the container body 10 and the outer surface of the container body 10 in substantially the same manner as in the case of FIGS. 5A to 5F described above. The composite container 10A including the contracted tube 40 is obtained (see FIGS. 6E to 6G).

As described above, according to the present embodiment, by performing blow molding on the composite preform 70 in the blow molding die 50, the preform 10a of the composite preform 70 and the plastic member 40a are formed. The container is inflated as a unit to produce a composite container 10A including the container body 10 and the plastic member 40. As a result, the preform 10a (container body 10) and the plastic member 40a (plastic member 40) can be configured as separate members. Therefore, various functions and characteristics can be freely added to the composite container 10A by appropriately selecting the type and shape of the plastic member 40.

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

Second Embodiment Next, a second embodiment of the present invention will be described with reference to the drawings. 7 to 12 are views showing a second embodiment of the present invention. 7 to 12, the same parts as those in the first embodiment are designated by the same reference numerals and detailed description thereof will be omitted.

First, an outline of a composite container manufactured by the blow molding method according to the present embodiment will be described with reference to FIGS. 7 and 8.

As will be described later, the composite container 10A shown in FIGS. 7 and 8 is a composite preform 70 (see FIG. 9) including the preform 10a, the inner label member 60a, and the plastic member 40a using the blow molding die 50. By subjecting the composite preform 70 to the preform 10a of the composite preform 70, the inner label member 60a, and the plastic member 40a, they are integrally expanded by biaxial stretching blow molding.

Such a composite container 10A is provided inside a container body 10 made of a plastic material, an inside label member 60 closely attached to the outside of the container body 10, and an outside label of the inside label member 60. And a plastic member 40 that has been formed.

Of 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, and a body portion 20 provided below the shoulder portion 12, And a bottom portion 30 provided below the body portion 20.

On the other hand, the inner label member 60 is in close contact with the outer surface of the container body 10 in a thinly extended state, and is in close contact with the container body 10 so as not to easily move or rotate.

Further, the plastic member 40 is a heat-shrinkable tube, and is adhered to the outer surface of the container body 10 and the outer surface of the inner label member 60 in a thinly extended state, and is easily moved or rotated with respect to the container body 10. It is so close that it does not fall off, or that it does not fall under its own weight.

It is conceivable that at least a part of the plastic member 40 is translucent or transparent, and in this case, the inner label member 60 is visible from the outside through the translucent or transparent part. The plastic member 40 may be semitransparent or transparent as a whole, or may have an opaque portion and a semitransparent or transparent portion (for example, a window portion). In the present embodiment, the case where the entire plastic member 40 is transparent will be described as an example.

Next, the inner label member 60 will be described. The inner label member 60 (60a) is provided so as to surround the outside of the preform 10a as described later, and is obtained by integrally biaxially stretch-blow molding the preform 10a and the plastic member 40a. It is a thing.

The inner label member 60 is attached to the outer surface of the container body 10 without being adhered, and is in close contact with the container body 10 so as not to move or rotate, or in such a degree that it does not drop by its own weight. .. The inner label member 60 is thinly stretched on the outer surface of the container body 10 to cover the container body 10. As shown in FIG. 7, the inner label member 60 is provided over the entire area in the circumferential direction so as to surround the container body 10, and has a substantially circular horizontal cross section.

In this case, the inner label member 60 is provided so as to cover the shoulder portion 12 and the body portion 20 of the container body 10 except the mouth portion 11, the neck portion 13 and the bottom portion 30. As a result, desired characters, images, and the like can be given to the shoulder portion 12 and the body portion 20 of the container body 10 so that the composite container 10A can be decorated and information can be displayed.

The inner label member 60 may be provided in the whole or a part of the container body 10 other than the mouth portion 11. For example, the inner label member 60 may be provided so as to cover a part of the neck portion 13, the shoulder portion 12, the body portion 20, and the bottom portion 30 of the container body 10 excluding the mouth portion 11. Alternatively, the inner label member 60 may be provided so as to cover the entire area of the neck portion 13, the entire area of the shoulder portion 12, the entire area of the body portion 20, and a part of the bottom portion 30. Further, the number of the inner label member 60 is not limited to one, and a plurality of inner label members 60 may be provided. The inner label member 60 may be provided in the same region as the plastic member 40, or may be provided in a region narrower than the plastic member 40. In the latter case, the inner label member 60 is preferably completely covered by the plastic member 40.

The thickness of the inner label member 60 is not limited to this, but may be, for example, about 5 μm to 50 μm in a state of being attached to the container body 10.

Next, the plastic member 40 will be described. The plastic member 40 (40a) is provided so as to surround the outside of the inner label member 60a as described later, and is obtained by integrally biaxially stretch-blow molding the preform 10a and the inner label member 60a. It is a thing.

The plastic member 40 is attached to the outer surface of the inner label member 60 without being adhered, and is adhered so as not to move or rotate with respect to the container body 10, or so closely that it does not drop by its own weight. There is. The plastic member 40 covers the inner label member 60 by being thinly stretched on the outer surface of the inner label member 60. As shown in FIG. 8, the plastic member 40 is provided over the entire area in the circumferential direction so as to surround the container body 10, and has a substantially circular horizontal cross section.

In addition, the configurations of the container body 10 and the plastic member 40 are substantially the same as those in the case of the above-described first embodiment, and thus detailed description thereof will be omitted here.

Next, the configuration of the composite preform according to the present embodiment will be described with reference to FIG.

As shown in FIG. 9, the composite preform 70 includes a preform 10a made of a plastic material, a bottomless cylindrical inner label member 60a provided in close contact with the outside of the preform 10a, and an inner label member 60a. And a bottomless cylindrical plastic member 40a provided in close contact with the outside.

The inner label member 60a is in close contact with the outer surface of the preform 10a, and is in close contact with the preform 10a without being easily moved or rotated, or is in close contact with the preform 10a to the extent that it does not drop by its own weight. The inner label member 60a is provided over the entire area in the circumferential direction so as to surround the preform 10a and has a substantially circular horizontal cross section.

The inner label member 60a may be designed or printed in advance. For example, in addition to the design, the product name, etc., character information such as the name of the content liquid, the manufacturer, the raw material name, etc. may be described. In this case, it is possible to display an image or a character on the composite container 10A without adding a label or the like to the container body 10 after the blow molding. For example, the inner label member 60a may be provided on all or part of the body portion 20a of the preform 10a so that images and characters are displayed on the body portion 20 of the container body 10 after molding. This eliminates the need for a step of applying a label using a labeler after the container is sealed up, so that the manufacturing cost can be suppressed and the yield can be prevented from decreasing.

As such an inner label member 60a, a film made of a polyester resin, a polyamide resin, a polyaramid resin, a polypropylene resin, a polycarbonate resin, a polyacetal resin, a fluorine resin, a blended material thereof, or the like is used. You can The inner label member 60a may be made of the same material as the container body 10 (preform 10a) and/or the plastic member 40a, or may be made of a different material.

Further, various materials described below can be used as the inner label member 60a.

For example, the inner label member 60a 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 enhanced, 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 prevent the decrease of the internal volume. As such a material, it is possible to mix PE, PP, MXD-6, EVOH, PEN, or an oxygen absorbent such as a fatty acid salt with these materials.

Further, the inner label member 60a may be made of a material having a light barrier property against ultraviolet rays and the like. In this case, without using a multi-layer preform or a preform containing a blend material as the preform 10a, it is possible to enhance the light barrier property of the composite container 10A and prevent the content liquid from being deteriorated by ultraviolet rays or the like. 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.

The inner label member 60a may be made of a material having a higher heat retention property or a lower heat retention property (a material having a lower heat conductivity) than the plastic material forming 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 heat retaining property or the cold retaining property of the composite container 10A is enhanced. Examples of such a material include foamed polyurethane, polystyrene, PE, PP, phenol resin, polyvinyl chloride, urea resin, silicone, polyimide, melamine resin and the like. The inner label member 60a preferably further contains hollow particles. The average particle diameter of the hollow particles is preferably 1 to 200 μm, more preferably 5 to 80 μm. The hollow particles may be organic hollow particles composed of a resin or the like, or may be inorganic hollow particles composed of a glass or the like, but the organic particles are excellent because of excellent dispersibility. Hollow particles are preferred. As the resin constituting the organic hollow particles, the same resins as those mentioned above can be mentioned.
Further, the commercially available hollow particles can also be used. The content of the hollow particles is preferably 0.01 to 50 parts by mass, and more preferably 1 to 20 parts by mass with respect to 100 parts by mass of the resin contained in the inner label member 60a.

On the other hand, the plastic member 40a is attached to the outer surface of the inner label member 60a without being adhered, and is adhered to the preform 10a so as not to move or rotate, or to such an extent that it does not drop by its own weight. Has been done. The plastic member 40a is provided over the entire area in the circumferential direction so as to surround the preform 10a and has a substantially circular horizontal cross section.

In this case, the inner label member 60a and the plastic member 40a are provided so as to cover the entire body portion 20a except the portion 13a corresponding to the neck portion 13 of the container body 10.

The inner label member 60a and the plastic member 40a may be provided in the whole area or a partial area other than the mouth portion 11a. For example, the inner label member 60a and the plastic member 40a may be provided so as to cover the entire body portion 20a including the neck portion 13. Further, each of the inner label member 60a and the plastic member 40a is not limited to one, but a plurality of members may be provided. For example, the two inner label members 60a and the plastic member 40a may be provided at two positions outside the body portion 20a.

The plastic member 40a has a function of contracting with respect to the preform 10a, and contracts (for example, heat contracts) with respect to the preform 10a when heat is applied.

In addition, the configurations of the preform 10a and the plastic member 40a are substantially the same as those in the above-described first embodiment, and therefore detailed description thereof will be omitted here.

Next, the shapes of the plastic member 40a and/or the inner label member 60a will be described.

As shown in FIG. 10, it is preferable that the plastic member 40a (inner label member 60a) has a cylindrical body portion 41 (body portion 61) having a bottomless cylindrical shape as a whole.
In this case, various functions and characteristics can be given to the composite container 10A.

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

First, a preform 10a made of a plastic material is prepared (see FIG. 11(a)).

Next, the inner label member 60a is provided on the outer side of the preform 10a, and the plastic member 40a is provided on the outer side of the inner label member 60a (see FIG. 11B). The inner label member 60a and the plastic member 40a are attached so as to cover the entire body portion 20a except the portion corresponding to the neck portion 13 of the container body 10. At least a part of the plastic member 40a may be semitransparent or transparent.

In this case, a plastic member 40a may be provided in advance around the inner label member 60a, and the inner label member 60a and the plastic member 40a may be integrally attached to the outside of the preform 10a. Alternatively, the inner label member 60a may be provided on the outer side of the preform 10a, and then the plastic member 40a may be provided on the outer side of the inner label member 60a.

Next, the preform 10a, the inner label member 60a, and the plastic member 40a are heated by the heating device 51 (see FIG. 11C). At this time, the preform 10a, the inner label member 60a, and the plastic member 40a are uniformly 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, the inner label member 60a, and the plastic member 40a in this heating step may be, for example, 90°C to 130°C.

By heating the plastic member 40a in this manner, the plastic member 40a is thermally shrunk and adheres to the outside of the preform 10a (see FIG. 11C).

Then, the preform 10a, the inner label member 60a, and the plastic member 40a heated by the heating device 51 are sent to the blow molding die 50 (see FIG. 11D).

The preform 10a, the inner label member 60a, and the plastic member 40a are molded using this blow molding die 50, and are substantially the same as the container body 10 in the same manner as in the case of FIGS. 11(a) to 11(f) described above. A composite container 10A including an inner label member 60a provided on the outer surface of the container body 10 and a plastic member 40 provided on the outer side of the inner label member 60a is obtained (FIGS. 11D to 11F). reference).

Next, another modified example of the blow molding method (method for manufacturing the composite container 10A) according to the present embodiment will be described with reference to FIGS. The modified example shown in FIGS. 12(a) to 12(g) heats the preform 10a and the plastic member 40a in two stages, and other configurations are the forms shown in FIGS. 11(a) to 11(f). Is almost the same as. 12A to 12G, the same parts as those in FIGS. 11A to 11F are denoted by the same reference numerals and detailed description thereof will be omitted.

First, a preform 10a made of a plastic material is prepared (see FIG. 12(a)).

Next, the inner label member 60a is provided on the outer side of the preform 10a, and the plastic member 40a is provided on the outer side of the inner label member 60a (see FIG. 12B). The plastic member 40a is attached so as to cover the entire body portion 20a except the portion corresponding to the neck portion 13 of the container body 10. At least a part of the plastic member 40a may be semitransparent or transparent.

In this case, a plastic member 40a may be provided in advance around the inner label member 60a, and the inner label member 60a and the plastic member 40a may be integrally attached to the outside of the preform 10a. Alternatively, the inner label member 60a may be provided on the outer side of the preform 10a, and then the plastic member 40a may be provided on the outer side of the inner label member 60a.

Next, the preform 10a, the inner label member 60a, and the plastic member 40a are heated by the first heating device 55 (see FIG. 12(c)). At this time, the heating temperature of the preform 10a, the inner label member 60a, and the plastic member 40a may be, for example, 50°C to 100°C.

By heating the plastic member 40a, the plastic member 40a is heat-shrinked and adheres to the outside of the preform 10a. As a result, a composite preform 70 having the preform 10a, the inner label member 60a adhered to the outside of the preform 10a, and the plastic member 40a adhered to the outside of the inner label member 60a is obtained (FIG. 12). (See (c)).

As described above, the composite preform 70 is produced by heating and closely adhering the plastic member 40a to the outside of the preform 10a and the inner label member 60a using the first heating device 55 in advance. 12 (a) to (c)) and a series of steps (FIGS. 12 (d) to (g)) for making the composite container 10A by blow molding are provided at different places (factory etc.). ) Can be carried out.

Next, the composite preform 70 is heated by the second heating device 51 (see FIG. 12D). At this time, the composite preform 70 is uniformly heated in the circumferential direction by the second heating device 51 while rotating with the mouth portion 11a facing downward. The heating temperature of the preform 10a, the inner label member 60a, and the plastic member 40a in this heating step may be, for example, 90°C to 130°C.

Subsequently, the composite preform 70 heated by the second heating device 51 is sent to the blow molding die 50 (see FIG. 12(e)).

The composite preform 70 is molded by using this blow molding die 50, and is provided on the container body 10 and the outer surface of the container body 10 in substantially the same manner as in the case of FIGS. 11(a) to 11(f) described above. A composite container 10A including the inner label member 60 and the plastic member 40 provided outside the inner label member 60 is obtained (see FIGS. 12E to 12G).

As described above, according to the present embodiment, by performing blow molding on the composite preform 70 in the blow molding die 50, the preform 10a of the composite preform 70, the inner label member 60a, and The plastic member 40a is integrally expanded to produce a composite container 10A including the container body 10, the inner label member 60, and the plastic member 40. Therefore, at the stage of manufacturing the composite container 10A using the preform 10a, the inner label member 60 can be provided in advance in the composite container 10A. Therefore, it is not necessary to provide a step of applying a label by the labeler after filling the content liquid in the composite container 10A and sealing the container tightly. Thereby, the manufacturing cost for manufacturing the final product can be suppressed.
Further, it is possible to prevent the yield from being lowered when the final product is manufactured due to a problem of the labeler or the like.

Further, according to the present embodiment, the preform 10a (container body 10) and the plastic member 40a (plastic member 40) can be configured as separate members. Therefore, various functions and characteristics can be freely added to the composite container 10A by appropriately selecting the type and shape of the plastic member 40.

Further, according to the present embodiment, when manufacturing the composite container 10A, a general blow molding device can be used as it is, so that it is necessary to prepare a new molding facility for manufacturing the composite container 10A. Absent.

Claims (5)

For manufacturing a composite container having the preform and a plastic member adhered to the outside of the preform by being attached so as to surround the outside of the preform and being heated integrally with the preform. A method of manufacturing a plastic member, comprising:
(1) A step of heating and melting a resin material containing a crosslinkable resin,
(2) a step of extruding the heat-melted resin material to obtain an extruded product,
(3) a step of expanding the diameter of the extruded product,
(4) a step of irradiating the expanded product having an increased diameter with an actinic ray to crosslink the crosslinkable resin,
The method, wherein the plastic member is a heat-shrinkable tube and is printed. The method according to claim 1, wherein the resin material comprises a crosslinking agent and/or a crosslinking aid. The method according to claim 1, wherein the actinic ray is an electron beam. The method according to claim 3, wherein the dose of the electron beam is 1 to 1000 kGy. In the method of manufacturing a composite container,
A step of preparing a preform made of a plastic material,
Providing a plastic member obtained by the method according to any one of claims 1 to 4 on the outside of the preform,
Heating the preform and the plastic member and inserting them into a blow mold,
Blow-molding the preform and the plastic member in the blow mold to expand the preform and the plastic member as a unit.

Images