JP5059893B2 - Plastic container - Google Patents

Description

  The present invention relates to a container made of a synthetic resin such as polyethylene terephthalate (PET), polypropylene (PP), or polyethylene (PE), and further increases the strength (rigidity) of the container without increasing the amount of resin used. It is intended to simplify the sorting work at the time of disposal.

  Synthetic resin containers typified by plastic bottles are lightweight, easy to handle, can ensure transparency, and have the advantage of an appearance comparable to glass containers. In addition, since it is inexpensive, it has been frequently used as a container filled with beverages, seasonings, alcoholic beverages, detergents or drugs in recent years.

  By the way, this kind of container is difficult to recycle and dispose of, and it is desired to reduce the amount of resin used per container as much as possible in order to reduce the amount of waste discharged. If the amount is simply reduced, the rigidity of the container itself is lowered, so that it is easily deformed, leading to a loss of commercial value.

  For this reason, synthetic resin containers have conventionally reduced the amount of resin used by adding ingenuity to the external shape (especially the planar shape) of the container and providing recesses with various shapes in the body of the container body. However, the rigidity of the container itself is ensured (see Patent Document 1).

  In addition, from the viewpoint of recycling, it has also been proposed to dispose of used containers with easy peeling means such as knobs, perforations and notches for separating and separating labels from the container body. (See Patent Document 2).

JP-A-6-127542 JP 2002-120848 A

  An object of the present invention is to propose a new synthetic resin container that can further increase the strength and rigidity of the container without increasing the amount of resin used and can omit the work for separation and disposal.

The present invention is a synthetic resin container comprising a container body and having a plurality of compartment recesses in the body portion of the container body ,
The container body is a biaxially stretched blow bottle having a capacity of 500 ml with a PET resin usage amount of 21 g, and the label has a base material layer made of PET resin with a thickness of 40 μm. and shrink label coated with the adhesive under the condition of 10 g / m ^2, surrounds the shrink label to the body of the bottle, the shrink label, the barrel by hold down with a force forces the container is inflated label contracts a synthetic resin container, characterized in that an increased rigidity of the container firmly adhered.

  The label can be attached to the entire circumference of at least the upper end and the lower end of the label. Moreover, the said label can also be affixed on the trunk | drum except a division recess.

  According to the present invention, since the label itself, or the label and the adhesive layer function as a reinforcing member for the container, the strength of the container can be further improved without increasing the amount of resin used, which is useful for resource saving.

  Generally, in the content filling line, after filling the content, a shower process is performed for the purpose of heat sterilization or cooling. Therefore, by attaching a label before reaching the shower process, Invasion of water is avoided, so the occurrence of wrinkles can be prevented and the hygiene is excellent.

  Further, according to the present invention, when a heat shrink type label such as a shrink label is used, the force that the container expands in heat filling, heat sterilization, etc. can be suppressed by the force that the label shrinks. Since deformation is suppressed and the sealed space also functions as a heat insulating layer, the container can be easily gripped even if the contents are held at a high temperature.

  Furthermore, according to the present invention, since the container and the base material layer are substantially the same material, the separation work can be omitted when the container is discarded.

It is the figure which showed embodiment of this invention. It is the figure which showed the LL cross section of FIG. It is the figure which showed other embodiment of this invention. It is the figure which expanded and showed the B section of FIG. It is the figure which expanded and showed the B section of FIG. It is the figure which expanded and showed the principal part of the label. It is the figure which showed the state which shape | molded the label shown in FIG. 6 in the cylinder shape. (A) is the figure which showed the side surface of the container suitable for mounting | wearing with a non-adhesion type label, (b) is the figure which showed the II cross section of (a). It is the figure which showed the test point of the trunk | drum rigidity of a container.

  Hereinafter, the present invention will be described more specifically with reference to the drawings. 1 and 2 show a container made of a synthetic resin according to the present invention as an example of a bottle-type container, FIG. 1 is a side view of the container, and FIG. 2 is a sectional view taken on line LL in FIG. It is.

  In FIG. 1, reference numeral 1 denotes a container main body having an internal space for filling the contents, 2 denotes a mouth integrally connected to the container main body 1, and 3 denotes a plurality of partition recesses provided in the trunk of the container main body 1. The partition recess 3 constitutes a reduced pressure absorption panel that prevents deformation due to the reduced pressure in the container that occurs when, for example, the high temperature filled contents are cooled. Here, the said trunk | drum shall point out the whole side peripheral wall of the container main body 1 except the opening | mouth part 2 of the container main body 1, and its bottom part 1a.

  Reference numeral 4 denotes a label that covers the concavity recess 3 and forms a sealed space (air layer) A (see FIG. 2) between the container body 1 and the body. The label 4 is made of substantially the same material as the container, and is attached to the body of the container body 1 excluding the partition recess 3 via an adhesive layer 4a. In the present invention, a label made of substantially the same material as the container means that at least the base material layer of the label is made of the same material as the main material constituting the container.

  When the label 4 is attached to the body portion via the adhesive layer 4a, a layer of air isolated from the outside air is formed in the partition recess 3, which relieves a reinforcing material that increases the rigidity of the container and an external impact. Functions as a cushioning material.

  In FIG. 1 and FIG. 2, the case where the label 4 is attached to the body portion excluding the partition recess 3 of the container is shown. It may be attached, or in addition to this, it is possible to attach along the longitudinal direction at several places on the body of the container body 1, and this also increases the rigidity of the container. Moreover, the adhesive layer 4a of the label 4 may be provided on the entire back surface of the label, or may be provided only at a necessary portion, and this point is not limited. The example at the time of sticking along the longitudinal direction in the upper end part and lower end part of the label 4 and the trunk | drum of the container main body 1 in several places in FIG. 3 is shown.

  As shown in FIG. 4 by enlarging the portion B in FIG. 2, the label 4 basically has a two-layer structure that is adhered to the container body 1 via an adhesive layer (heat-sensitive adhesive or the like) 4a. However, as shown in FIG. 5, the label 4 has a layer structure composed of a base material 4b made of substantially the same material as the container body 1 and a barrier layer 4c overlapping the base material 4b. A layer structure in which a printing layer is provided between them can also be used.

  FIG. 6 is an enlarged view of an essential part showing a label (shrink label) suitable for application to the synthetic resin container according to the present invention in the form of a sheet. A heat-sensitive adhesive is applied to the surface of the sheet-like film, which is the substrate 4b, except for one end thereof to form an adhesive layer 4a. The end of the end is covered with the adhesive 5 while being rolled as shown in FIG. By connecting and producing a cylindrical label, the bonding portion of the label is, in order from the inside, adhesive layer 4a (thermal adhesive) / base material 4b / adhesive layer 4a (thermal adhesive and adhesive 5 / base material 4b). Thus, the gas can be prevented from permeating from the connecting portion, and the strength can be further increased.

  In addition to the heat shrink type shrink label, the label 4 can be applied with a stretch label formed by forming a self-stretchable stretch film into a cylindrical shape as a reference technique, especially for shrink labels. It is preferable to use substantially the same resin as the container in that it is possible to save the labor of peeling the label 4 from the container when the used container is discarded, and that the deformation characteristics tend to be the same (easy to control). .

  Further, when using a non-adhesive label (a label having no adhesive layer) to be brought into close contact with the body portion of the container body 1 as the label 4, an annular groove portion 6 as shown in FIGS. It is desirable to use at least one container on the top and bottom of the label, and this improves the adhesion of the label 4.

  The container is formed by a conventional technique such as blow molding or injection molding, and resins such as PET, PP, and PE can be used. However, the present invention is not limited only to these resins. Further, the shape of the container can be adapted to any shape such as a bottle shape or a cup shape.

A container with a filling capacity of 500 milliliters and an outer shape as shown in Fig. 1 having a section recess in the body (the resin used is PET resin, the amount used is 21 g, biaxially stretched blown) After molding, a label (PET resin with a base material layer thickness of 40 μm and a thermal paste (adhesive) was applied at 10 g / m ^{2 on} the barrel part. A shrink label (Compliance Example 1) and a non-adhesive shrink label (Compliance Example 2)) are attached (the shrink label is covered with an empty container and contracted with steam), and the buckling strength and trunk rigidity of the container And the column stiffness was investigated. The result is shown in Table 1 together with the result of the container without the label (Comparative Example).

  “Empty” in the table means an empty container not filled with contents, and “filling” means filling a specified amount of hot water at 87 ° C., and then tightening the cap for 45 seconds. It means the case of water-cooling after rolling upside down for 5 minutes and 15 seconds.

  The “buckling strength (N)” is a compression of an upright container from its top (mouth side) to the bottom using a disk with a diameter of 100 mm at a speed of 50 mm / min. The value when bent (for empty containers, measured by providing an air vent between the mouth and the disk) is displayed as an index, and the “body rigidity (mm)” is stored at 5 ° C for 24 hours. The container is rolled over so that one of its column parts (the convex part between the compartment recesses) is on the upper surface, and the width is 10 mm × 10 mm so as to be parallel to the axis connecting the mouth side and the bottom side of the container. A square bar having a length of 150 mm is disposed (one end of the square bar is positioned 20 mm from the bottom of the container. See FIG. 9), and 58.8 N is vertically directed from the upper surface side to the lower surface side by the square bar. The amount of displacement when compressed by applying a load of (6 kgf) is displayed as an index, and “column stiffness (N)” is A column of 20 mm in diameter and 100 mm in length is placed so that one of the column parts of the container rolls over so that the top surface is aligned, and the axis is perpendicular to the axis connecting the mouth side and the bottom side of the container. The value when the container is buckled by compressing the central part of the part vertically from the upper surface side to the lower surface side is displayed as an index.

  As is apparent from Table 1, the conforming example 2 in which the shrink label is not attached to the trunk of the container body has improved buckling strength, trunk rigidity, and column rigidity compared to the comparative example in which no label is attached. In particular, it was confirmed that all of buckling strength, body rigidity, and column rigidity were improved in the case of the fitting example 1 in which the shrink label was attached by bonding as compared with the fitting example 2.

  In addition, the investigation results of the conformity examples 1 and 2 are those when the so-called pre-label method is adopted, in which the contents are filled after attaching the label to the empty container, but the labels are attached after filling the contents. The same result was obtained when the so-called after-label method was adopted.

  It is possible to supply a synthetic resin container with sufficient strength and rigidity while minimizing the amount of resin used.

DESCRIPTION OF SYMBOLS 1 Container main body 1a Bottom part 2 Mouth part 3 Compartment recess 4 Label (heat shrink type)
4a Adhesive layer 4b Base material 4c Barrier layer 4d Print layer 5 Adhesive layer

Claims (3)

A container made of a synthetic resin, comprising a container body, and having a plurality of compartment recesses in the body of the container body,
The container body is a biaxially stretched blow bottle having a capacity of 500 ml with a PET resin usage amount of 21 g, and the label has a base material layer made of PET resin with a thickness of 40 μm. A shrink label with an adhesive applied under the condition of 10 g / m ² ,
It surrounds the shrink label to the body of the bottle, and characterized in that the shrink label, the container has increased the rigidity of the container firmly adhered to the body portion by hold down with a force shrink label a force that expands contracts A synthetic resin container. The synthetic resin container according to claim 1, wherein the label is affixed over the entire circumference of at least an upper end portion and a lower end portion of the label . The synthetic resin container according to claim 1 or 2, wherein the label is affixed to a body portion excluding a partition recess .

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