JP2019188646A - Production method of blow molding container, blow molding mold, blow molding transfer sheet, and blow molding container - Google Patents

Abstract

To provide a production method of a blow molding container, a blow molding mold, a blow molding transfer sheet, and a blow molding container, which can readily change an irregular shape of a surface of a blow molding container.SOLUTION: A production method of a blow molding container includes: a step of preparing a parison 10a; a step of preparing a blow molding mold 50 having a mold body 52 and a transfer sheet 60 adhered to an inner surface of the mold body 52; and a step of preparing a blow molding container 10A by blow molding the parison 10a in the blow molding mold 50. On an exterior surface of the blow molding container 10A, a surface shape of the transfer sheet 60 adhered to the inside of the blow molding mold 50 is transferred.SELECTED DRAWING: Figure 2

Description

  The present disclosure relates to a method for manufacturing a blow molded container, a blow mold, a transfer sheet for blow molding, and a blow molded container.

  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, conventionally, when forming a pattern such as irregularities on the surface of a plastic bottle, irregularities are formed on the inner surface of the blow molding die by machining or the like, and the irregularities on the inner surface of the mold are blown to the surface of the plastic bottle at the time of blow molding. Is generally transferred (see, for example, Patent Document 1). For this reason, when it is going to change the uneven | corrugated shape of the surface of a plastic bottle, it is necessary to remanufacture a blow molding die itself, and cost and time are taken.

JP 2009-241971 A

  The present disclosure has been made in consideration of such points, and can provide a method for manufacturing a blow molded container, a blow mold, and a transfer for blow molding that can easily change the uneven shape of the surface of the blow molded container. Sheets and blow molded containers are provided.

  A blow molded container manufacturing method according to an embodiment is a blow molded container manufacturing method comprising a step of preparing a parison, a mold body, and a transfer sheet adhered to the inner surface of the mold body. A step of preparing a mold, and a step of blow-molding the parison in the blow mold to produce a blow-molded container, which is adhered to the outer surface of the blow-molded container on the inner surface of the mold body. The surface shape of the transfer sheet is transferred.

  In the blow molded container manufacturing method according to an embodiment, the surface of the transfer sheet may have an uneven shape.

  In the blow molded container manufacturing method according to one embodiment, the surface of the transfer sheet may be mirror-finished.

  In the blow molded container manufacturing method according to an embodiment, the mold body may be a resin mold.

  A blow mold according to an embodiment is a blow mold, and includes a mold body and a transfer sheet attached to the inner surface of the mold body.

  In the blow mold according to an embodiment, the surface of the transfer sheet may have an uneven shape.

  In the blow mold according to an embodiment, the surface of the transfer sheet may be mirror-finished.

  In the blow mold according to an embodiment, the mold body may be a resin mold.

  The transfer sheet for blow molding according to an embodiment is a transfer sheet for blow molding, and is disposed on the adhesive layer to be attached to the blow molding die and transferred onto the outer surface of the blow molding container. A transfer layer having a shape to be formed.

  In the transfer sheet for blow molding according to an embodiment, the surface of the transfer layer may have an uneven shape.

  In the blow molding transfer sheet according to an embodiment, the surface of the transfer layer may be mirror-finished.

  The transfer sheet for blow molding according to an embodiment may further include a release paper provided on the adhesive layer.

  A blow-molded container according to an embodiment is a blow-molded container having an outer surface, onto which the surface shape of a transfer sheet attached to a blow mold for molding the blow-molded container is transferred.

  According to the present disclosure, the uneven shape of the surface of the blow molded container can be easily changed.

FIG. 1 is a partial vertical sectional view showing a blow molded container according to an embodiment. Drawing 2 (a)-(e) is a schematic diagram showing the manufacturing method of the blow molding container by one embodiment. FIG. 3 is a cross-sectional view illustrating a transfer sheet according to an embodiment. FIG. 4 is a partial vertical sectional view showing a blow molded container according to a modification.

  Hereinafter, an embodiment will be described with reference to the drawings. 1 to 3 are diagrams showing an embodiment. Each figure shown below is shown schematically. Therefore, the size and shape of each part are exaggerated as appropriate for easy understanding. In addition, the present invention can be implemented with appropriate modifications without departing from the technical idea. Note that, in the drawings shown below, the same portions are denoted by the same reference numerals, and some detailed description may be omitted. In addition, the numerical values such as the dimensions of the respective members and the material names described in the present specification are examples of the embodiment, and are not limited thereto, and can be appropriately selected and used. In this specification, terms specifying the shape and geometric conditions, for example, terms such as parallel, orthogonal, and vertical are intended to include substantially the same state in addition to being strictly meant.

Configuration of Blow Molded Container First, an outline of a blow molded container according to the present embodiment will be described with reference to FIG. In the present specification, “upper” and “lower” refer to the upper side and the lower side in a state where the blow-molded container 10A is erected (FIG. 1), respectively.

  A blow molded container 10A shown in FIG. 1 is obtained by expanding a preform 10a by performing biaxial stretch blow molding on the preform 10a using a blow mold 50, as will be described later. is there.

  Such a blow-molded container 10A 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 trunk portion 20 provided below the shoulder portion 12. The bottom part 30 provided below the trunk | drum 20 is provided.

  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 blow molded container 10A is filled with contents such as a content liquid, and a cap (not shown) is screwed into the mouth portion 11 to produce a blow molded container containing the contents.

  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 trunk portion 20, and has a shape in which the diameter gradually increases from the neck portion 13 side toward the trunk portion 20 side (the area gradually increases in the horizontal section). Shape).

  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.

  In the present embodiment, a transfer region 23 is formed on the outer surface of the body portion 20. The transfer region 23 is a transfer of the surface shape of a transfer sheet 60 (described later) adhered in a blow mold 50 for forming the blow molded container 10A. The transfer region 23 has an uneven shape. Such an uneven shape may be a regular or irregular uneven pattern such as a texture. The depth of the uneven pattern (the difference between the most protruding portion and the most recessed portion) may be, for example, 1 μm or more and 500 μm or less. Or as an uneven | corrugated shape, the unevenness | corrugation with fixed outlines, such as a character and a pattern, may be sufficient. The depth of the unevenness having a certain contour (the difference between the most protruding portion and the most recessed portion) may be, for example, 1 μm or more and 500 μm or less. In addition to the uneven shape, the transfer region 23 may be transferred with fine powder such as lame powder attached to the transfer sheet 60 instead of the uneven shape. In addition, irregularities other than the transfer region 23, for example, irregularities such as a reduced pressure absorption panel or a groove, may be formed on the outer surface of the body portion 20.

  The transfer region 23 may be formed on the entire outer surface of the trunk portion 20, or may be formed only on a part of the outer surface of the trunk portion 20. Further, the transfer region 23 is not limited to the body portion 20, and may be formed on a part of or the whole of the shoulder portion 12, the neck portion 13, and / or the bottom portion 30. In this embodiment, the transfer region 23 has a textured uneven shape (shaded portion in FIG. 1).

  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, although the thickness of 10 A of blow molding containers 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. Further, the weight of the blow molded container 10A is not limited to this, but can be 10 g or more and 20 g or less. Thus, by reducing the thickness of the blow molded container 10A, the weight of the blow molded container 10A can be reduced.

  Such a blow-molded container 10A can be produced by biaxially stretching blow-molding a preform 10a (described later) produced by injection molding a synthetic resin material. As a material for the blow molded container 10A, a thermoplastic resin, particularly PE (polyethylene), PP (polypropylene), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PC (polycarbonate), IO (ionomer) should be used. Is preferred. The blow molded container 10A 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. Furthermore, 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 blow molded container 10A in order to enhance the barrier property of the container.

  Further, the blow molded container 10A can be formed as a multilayer molded bottle having two or more layers. That is, by injection molding, for example, the intermediate layer is a resin (intermediate layer) having gas barrier properties such as MXD6, MXD6 + fatty acid salt, PGA (polyglycolic acid), EVOH (ethylene vinyl alcohol copolymer) or PEN (polyethylene naphthalate). Alternatively, a preform 10a having three or more layers may be formed by injection molding and then blow molding to form a multilayer bottle having gas barrier properties. 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, you may produce 10 A of blow molded containers. Since such a blow-molded container 10A incorporates foam cells, the light shielding property of the entire blow-molded container 10A can be improved.

  Such a blow-molded container 10A may consist of, for example, bottles with a full capacity of 100 ml to 2000 ml. Alternatively, the blow molded container 10A may be a large bottle having a full capacity of, for example, 10L to 60L.

Blow Molding Container Manufacturing Method Next, a manufacturing method (blow molding method) of the blow molded container 10A according to the present embodiment will be described with reference to FIGS.

  First, a preform (parison) 10a made of a plastic material is prepared (see FIG. 2A). In this case, for example, the preform 10a may be manufactured by an injection molding method using an unillustrated injection molding machine. Moreover, you may use the preform generally used conventionally as 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 11 a corresponds to the mouth portion 11 of the blow molded container 10 </ b> A described above, and has substantially the same shape as the mouth portion 11. Moreover, the trunk | drum 20a respond | corresponds to the neck part 13, the shoulder part 12, and the trunk | drum 20 of 10 A of blow molding containers mentioned above, and has a substantially cylindrical shape. The bottom 30a corresponds to the bottom 30 of the blow molded container 10A described above and has a substantially hemispherical shape.

  Next, the preform 10a is heated by the heating device 51 (see FIG. 2B). At this time, the preform 10a is heated uniformly in the circumferential direction by the heating device 51 while rotating with the mouth portion 11a facing downward. The heating temperature of the preform 10a in this heating step may be, for example, 90 ° C. to 130 ° C.

  Subsequently, the preform 10a heated by the heating device 51 is sent to the blow molding die 50 (see FIG. 2C).

  The blow molded container 10 </ b> A is molded using this blow mold 50. In this case, the blow mold 50 includes a mold body 52 that is a metal mold or a resin mold, and a transfer sheet 60 that is attached to the inner surface of the mold body 52. In the present embodiment, a blow molding die 50 having such a die body 52 and a transfer sheet 60 is also provided.

  The mold body 52 includes a pair of body molds 50a and 50b and a bottom mold 50c that are divided from each other (see FIG. 2C). The inner surface of the mold body 52 has a shape corresponding to the shoulder 12, neck 13, body 20, and bottom 30 of the blow molded container 10 </ b> A. In FIG. 2C, 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 preform 10a is inserted between the body molds 50a and 50b of the mold body 52.

  The transfer sheet 60 is attached to the inner surfaces of the pair of body part molds 50a and 50b, and is provided at a position corresponding to the transfer region 23 described above. The surface of the transfer sheet 60 has an uneven shape as described above.

  Next, as shown in FIG. 2D, 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 of the mold body 52 are closed. A blow molding die 50 sealed by the die 50c is configured. Next, air is press-fitted into the preform 10a, and biaxial stretch blow molding is performed on the preform 10a.

  Thus, the preform 10a is shaped into a shape corresponding to the inner surface of the blow mold 50, and a blow molded container 10A is obtained from the preform 10a in the blow mold 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. Further, in the blow mold 50, the uneven shape on the surface of the transfer sheet 60 is transferred to the body portion 20 of the blow molding container 10 </ b> A, and a transfer region 23 having unevenness is formed in the body portion 20. At this time, the transfer sheet 60 is pressed against the inner surface of the mold main body 52 along the normal direction of the surface along with the stretching of the blow molded container 10A. For this reason, the position of the transfer sheet 60 is difficult to shift during blow molding.

  Thereafter, as shown in FIG. 2 (e), the pair of body molds 50 a and 50 b and the bottom mold 50 c of the mold main body 52 are separated from each other, and the blow molded container 10 </ b> A is taken out from the blow mold 50. At this time, the transfer sheet 60 is separated from the blow molded container 10 </ b> A and remains on the inner surface of the mold body 52. In this way, the blow molded container 10A shown in FIG. 1 is obtained.

Next , the configuration of the transfer sheet according to this embodiment will be described with reference to FIG.

  As shown in FIG. 3, the transfer sheet 60 for blow molding according to the present embodiment is disposed on the mold body 52 of the blow mold 50 and the adhesive layer 61. And a transfer layer 62 having a shape transferred to the outer surface of the molding container 10A.

  The adhesive layer 61 may contain an adhesive. The pressure-sensitive adhesive is not particularly limited. For example, natural rubber-based resins, butyl rubber, polyisoprene, polyisobutylene, polychloroprene, styrene-butadiene copolymer resins and other synthetic rubber resins, silicone resins, acrylic resins Resin, vinyl acetate resin such as polyvinyl acetate and ethylene-vinyl acetate copolymer, urethane resin, acrylonitrile, hydrocarbon resin, alkylphenol resin, rosin, rosin triglyceride, hydrogenated rosin and other rosin resins are applicable. The thickness of the sticking layer 61 is good also as the range of 5 micrometers or more and 300 micrometers or less, for example.

  The sticking layer 61 can be peeled off from the mold main body 52, and can be peeled off manually or mechanically. Even if the sticking layer 61 remains in the mold main body 52, water can be removed. It can be removed by cleaning with alcohol. By removing the adhesive layer 61, the mold body 52 can be returned to the state before the transfer sheet 60 is applied. In this case, another transfer sheet 60 can be attached to the mold body 52 again.

  As the transfer layer 62, it is preferable to use a material excellent in weather resistance and heat resistance, such as vinyl chloride paper made of vinyl chloride resin. The thickness of the transfer layer 62 may be, for example, in the range of 10 μm to 3000 μm, and may be 10 μm to 100 μm in order to keep the bottle shape.

  The surface of the transfer layer 62 has an uneven shape. As such a concavo-convex shape, for example, a regular or irregular concavo-convex pattern such as a texture, or a concavo-convex having a constant contour such as a character or a pattern may be used. Further, a glossy fine powder such as lame powder may adhere to the surface of the transfer layer 62.

  A release paper 63 is provided on the adhesive layer 61. The release paper 63 is detachably attached to the opposite side of the transfer layer 62 on the adhesive layer 61. The transfer sheet 62 is directed to the inner surface of the mold main body 52 by peeling the release paper 63 from the adhesive layer 61 and attaching the adhesive layer 61 to the outer surface of the mold main body 52. By performing blow molding in this state, the uneven shape of the transfer layer 62 is transferred to the outer surface of the blow molded container 10A.

  The release paper 63 includes a base material such as high-quality paper, coated paper, impregnated paper, or a plastic film, and a release layer provided on one side of the base material. The release layer is not particularly limited as long as it is a material having releasability, and examples thereof include silicone resins, organic resin-modified silicone resins, fluorine resins, aminoalkyd resins, and polyester resins. These resins can be used in any of emulsion type, solvent type and solventless type.

  As described above, according to the present embodiment, blow molding is performed using the blow molding die 50 having the mold body 52 and the transfer sheet 60 adhered to the inner surface of the mold body 52. At this time, the surface shape of the transfer sheet 60 adhered to the mold body 52 is transferred to the outer surface of the blow molded container 10A. Thereby, the transfer area | region 23 which has uneven | corrugated shape can be easily formed in the surface of 10 A of blow molding containers. Further, the transfer sheet 60 attached to the mold body 52 can be easily peeled and replaced with another transfer sheet 60. For this reason, the uneven | corrugated shape of the surface of 10 A of blow molding containers can be changed easily and in a short time. In this case, since it is not necessary to remanufacture the mold body 52 itself, costs and time required for manufacturing the mold body 52 can be reduced. Furthermore, since the transfer sheet 60 can be attached to the existing mold body 52, various desired uneven shapes are formed on the surface of the blow molded container 10A while maintaining the overall shape of the existing mold body 52. Can be granted.

  In addition, according to the present embodiment, since the surface of the transfer sheet 60 has a concavo-convex shape, the concavo-convex shape of the transfer sheet 60 is transferred to the surface of the blow-molded container 10A, and the blow-molded container 10A having the concavo-convex shape can be easily obtained. Can be produced.

(Modification)
Next, a modification of the above embodiment will be described.

  In the above embodiment, the case where the transfer region 23 has an uneven shape has been described as an example. However, the present invention is not limited to this, and as shown in FIG. 4, the transfer region 23 may be formed in a mirror shape by transferring the surface of the mirror-finished transfer sheet 60. The surface roughness of the mirror surface may be, for example, Ra (arithmetic average roughness) 1.0 or less. The transfer sheet 60 is a sheet having a transfer layer whose surface is mirror finished, such as a gloss sheet. In this case, since the mirror-finished surface shape of the transfer sheet 60 is transferred to the surface of the blow-molded container 10A, the mirror-shaped transfer region 23 can be easily formed on the surface of the blow-molded container 10A. In particular, when the mold body 52 is made of, for example, a resin mold used for trial purposes, it is difficult to polish the surface of the resin mold, and the surface of the blow molded container 10A tends to be rough. On the other hand, the surface of the blow molded container 10A is mirror-like even when a resin mold is used by sticking the mirror-finished transfer sheet 60 to the inner surface of the mold body 52 and performing blow molding. Can be formed.

  Moreover, in the said embodiment, 10 A of blow molded containers demonstrated taking the case of producing by the biaxial stretch blow molding method as an example. However, the present invention is not limited to this, and the blow molded container 10A may be manufactured by a direct blow molding method. That is, a parison obtained by heating and melting the molding material and extruded into a tube shape is used, and the parison is molded in the blow mold 50 so that the surface shape of the transfer sheet 60 is transferred to the surface of the blow molded container 10A. good.

  Moreover, in the said embodiment, it demonstrated taking the case where the transfer sheet 60 was affixed on the inner surface of the type | mold main body 52 as an example. However, the present invention is not limited to this, and another transfer sheet may be attached onto the transfer sheet 60 attached to the inner surface of the mold body 52. That is, the transfer sheet 60 may be provided in multiple layers on the inner surface of the mold body 52. In this case, the other transfer sheet preferably has a smaller area than the transfer sheet 60. Accordingly, various types of shapes can be transferred to the surface of the blow molded container 10A by appropriately replacing another transfer sheet.

  It is also possible to appropriately combine a plurality of constituent elements disclosed in the embodiment and the modification examples as necessary. Or you may delete a some component from all the components shown by the said embodiment and modification.

10A Blow Molded Container 10a Preform (Parison)
DESCRIPTION OF SYMBOLS 11 Mouth part 12 Shoulder part 13 Neck part 14 Thread part 17 Flange part 20 Trunk part 23 Transfer area 30 Bottom part 31 Recessed part 32 Grounding part 50 Blow molding die 52 Type | mold main body 60 Transfer sheet 61 Adhesive layer 62 Transfer layer 63 Release paper

Claims (13)

A method of manufacturing a blow molded container,
Preparing the parison,
Preparing a blow mold having a mold body and a transfer sheet adhered to the inner surface of the mold body;
Blow molding the parison in the blow mold, and producing a blow molded container,
A method for producing a blow-molded container, wherein the surface shape of the transfer sheet adhered to the inner surface of the mold body is transferred to the outer surface of the blow-molded container.   The method for producing a blow molded container according to claim 1, wherein the surface of the transfer sheet has an uneven shape.   The method for manufacturing a blow molded container according to claim 1, wherein a surface of the transfer sheet is mirror-finished.   The method of manufacturing a blow molded container according to any one of claims 1 to 3, wherein the mold body is a resin mold. A blow mold,
A mold body;
A blow molding die comprising: a transfer sheet attached to an inner surface of the die body.   The blow molding die according to claim 5, wherein a surface of the transfer sheet has an uneven shape.   The blow molding die according to claim 5, wherein a surface of the transfer sheet is mirror-finished.   The blow mold according to any one of claims 5 to 7, wherein the mold body is a resin mold. A transfer sheet for blow molding,
An adhesive layer attached to a blow mold,
A transfer sheet for blow molding, comprising: a transfer layer disposed on the adhesive layer and having a shape transferred to the outer surface of the blow molded container.   The blow molding transfer sheet according to claim 9, wherein a surface of the transfer layer has an uneven shape.   The blow molding transfer sheet according to claim 9, wherein a surface of the transfer layer is mirror-finished.   The transfer sheet for blow molding according to any one of claims 9 to 11, further comprising a release paper provided on the adhesive layer. A blow molded container,
With an outer surface,
A blow-molded container in which a surface shape of a transfer sheet attached to a blow mold for molding the blow-molded container is transferred to the outer surface.