JP2887016B2 - Labeled squeezed container and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION Labeled squeezable containers for storing liquids such as foods, pharmaceuticals, cosmetics, detergents and industrial chemicals, particularly viscous liquids, and pressing down the body to squeeze the liquids and a method of manufacturing the same. It is about.

[0002]

2. Description of the Related Art Conventionally, a squeeze container of this type has a tensile modulus of 500 to 4 such as low density polyethylene.
It is manufactured by blow molding a 2,000 kg / cm ² flexible thermoplastic resin. Then, in order to display the product name and the effect on the container and to enhance the design, a sculpture is formed on a molding die and the concavo-convex pattern is formed on the surface of the body of the container.

[0003]

[0006] Such a structure in which irregularities are formed on the body wall cannot provide a sufficient design property. Therefore, it is conceivable that multicolor printed labels, such as those used for highly rigid cosmetic containers, are welded to the container simultaneously with the molding of the container. Because of the absence, the label shrinks, causing a phenomenon called orange skin in which the surface of the label is deformed in a wavy manner, and a bulge occurs at the edge of the label. In the case of a container having rigidity as in the past, the stress causing this contraction action can be prevented by supporting the rigidity of the body, but in the above-described squeezed container, the container body has flexibility. Therefore, the shrinkage stress of the label cannot be carried by the container body, and the label has bumps on the orange skin and edges.
The reason why such a defect occurs in the label is that the shrinkage of the label is smaller than the shrinkage amount of the portion of the container body where the label is welded.

[0004] Therefore, it is conceivable that the shrinkage rate of the label is made larger than that of the container body. However, in this case, the shrinkage of the welded portion of the label of the container body is larger than that of the other portions of the container body. In the case of a flexible container such as a squeezed container, there is a disadvantage that this portion is deformed inward and does not form a desired container shape.
In the present invention, the squeezed container itself has a design. Wrinkles and bumps can be prevented from occurring at the edge of the label on the body of the container body. To solve the disadvantage that the body of the container body is deformed inward and does not form a desired container shape. It is an object of the present invention to realize a labeled squeezed container having excellent characteristics and a method for manufacturing the same.

[0005]

In order to achieve the above object, a squeezing container with a label according to the present invention comprises a squeezing body, a squeezing port, and a bottom portion. A synthetic resin label having a thickness of 50 to 100 μm and a shrinkage ratio equal to or less than the shrinkage ratio of the container body is integrally welded at the time of blow molding, and the meat of the portion of the squeezed body portion where the label is welded. The ratio of the thickness to the thickness of the part where the label is not welded is 0.8
~ 1.2.

Further, the method of manufacturing a squeezed container with a label according to the present invention is characterized in that a label is temporarily fixed to an inner surface of a cavity of a split mold having a cavity for forming a container body including an opened squeezing body, a squeezing opening and a bottom. In the meantime, after a parison made of a thermoplastic resin melted by heating is arranged between the split molds, the mold is closed, and a pressure fluid is introduced into the paris so that the label is integrated with the container body during molding. In the molding method, the label is made of a synthetic resin having a thickness of 50 to 100 μm and a shrinkage ratio of not more than the shrinkage ratio of the container body, and the shape of the paris is squeezed out of the body. The ratio between the thickness of the portion where the label is welded and the thickness of the portion where the label is not welded is adjusted to be in the range of 0.8 to 1.2. It is.

[0007]

According to the present inventors, the occurrence of orange skin and the bulging of the edge of the label described above are caused not only by the relationship between the shrinkage of the label itself and the shrinkage of the welded portion of the container label, but also by the labeling of the container. The difference between the shrinkage amount of the welded part and the shrinkage amount of the part other than the part where the container label was welded, and the delay in cooling of the part where the container label was welded were noticed as being caused. It is. Generally, in blow molding, a parison is cooled by a pressurized fluid introduced therein and a split mold. However, in the case where the label is integrally welded during blow molding as in the present invention, since the divided mold and the parison are separated by the label, cooling by the divided mold cannot be expected. As a result, a delay in the cooling of the parison occurred, and it was found that the delay in the cooling of the parison appeared as wrinkles of the label. Specifically, the shrinkage is suppressed by using a synthetic resin label having the same or smaller shrinkage as the thermoplastic resin constituting the container body, and the thickness of the synthetic resin label is set to 50 to 100 μm. And the ratio of the thickness of the portion of the container body where the label is welded to the thickness of the portion where the label is not welded is in the range of 0.8 to 1.2, so that the label of the container body is welded. Smooth cooling of the label, suppressing the cooling delay that has conventionally occurred in this part, and performing almost the same cooling as the part where the label is not welded, causing orange skin and prominence of the label edge on the label This eliminates the disadvantage that the squeezed body of the container body is deformed inward without forming the desired shape of the squeezed container with a label.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One preferred embodiment of the present invention will be described with reference to the drawings, and the structure of the present invention will be described in detail.

FIG. 1 is a front view showing a squeezed container with a label according to the present invention.

As shown in FIG. 1, a squeezed container with a label is composed of a container body 1 composed of a squeezed squeezing port 2, a squeezed body 3 and a bottom 4, and a squeezed body 3.
And a label 5 made of a synthetic resin film integrally welded to the container, for example, used as a seasoning container.

A method for manufacturing the squeezed container 1 with a label according to the present invention will be described.

In FIG. 2, the split molds 11 are arranged at positions facing each other, and cavities 12 having the shape of a container are formed on the surfaces that abut each other.
An extruder head 13 (not shown) is provided above the split mold 11.
A tubular parison 14 made by heating and melting a thermoplastic resin is extruded from the head 13 and hangs down. The ratio of the thickness of the portion of the squeezed body 3 where the label is welded to the thickness of the portion where the label is not welded of the parison 14 is 0.8 to 0.8.
The shape is adjusted to be in the range of 1.2.

As a method of adjusting the shape, the head 1
The die or the core corresponding to the outlet of No. 3 is partially shaved in the circumferential direction, the interval between the resin flow paths is partially widened in the circumferential direction, and the thickness of the parison 14 is set to be partially thick in the circumferential direction. In consideration of the thickness of the squeezed body 3 and the ratio of expansion at the time of blow molding, the cross-sectional shape of the parison 14 is not a simple circle but an ellipse, a polygon, and the like. Some are formed by a deformed die formed into an organic shape, and others are formed by combining these.

On the inner surface of the cavity 12 of the split mold 11,
Label 5 is temporarily fixed. The label 5 is sucked by a vacuum hole 15 formed on the surface of the cavity 12 and communicated with a vacuum source (not shown). By the way, Fig. 4
As shown in FIG. 5, the label 5 has a base layer 5a and a printed layer 5b formed on one surface thereof, and an adhesive layer 5c formed on the other surface. The label 5 arranged in the cavity 12 is such that the printing layer 5b side is in contact with the cavity 12, and the adhesive layer 5c side is arranged outside (Paris side).

Next, as shown in FIG. 3, the divided mold 11 is closed, and the parison 14 is sandwiched between the divided molds 11.
A pressure fluid is introduced into the parison 14 to expand the parison 14 and to shape the parison 14 according to the shape of the cavity 12 of the split mold 11. At this time, Paris 14
Adheres to the adhesive layer 5c on the surface of the label 5, and
The adhesive layer 5c of the label 5 is melted by the heat held by
The parison 14 and the label 5 are welded together. Then, the parison 14 is cooled by the pressurized fluid introduced into the parison 14 and the split mold, and a container is formed in the split mold 11. Next, the introduction of the pressure fluid was stopped, and the split mold 1
1 is opened, and the labeled squeezed container 1 is taken out of the split mold 11.

The thermoplastic resin constituting the container body 1 of the labeled squeezed container according to the present invention has an elastic modulus (JISK).
7113) has a flexibility of 500 to 4000 kg / cm ² , and preferred examples thereof include a polyolefin-based resin having an elastic modulus in the range of 500 to 4000 kg / cm ² , especially low-density polyethylene, medium-density polyethylene,
Ethylene vinyl acetate copolymer resin, ethylene propylene copolymer resin or ionomer resin is preferred. The container body 1 may have a single-layer structure of the above-described thermoplastic simple substance or blend, or a multilayer structure in which these are the main layers and a barrier layer such as an ethylene vinyl alcohol copolymer resin is laminated.

The shrinkage ratio of the container body 1 is determined by the circumferential length (L) of the squeezing body in the cross-section direction of the inner surface of the cavity 12 of the split mold 11 and the cross-sectional direction of the squeezing body of the molded product formed thereby. In the circumferential length (l), it is expressed by (L-1) / L, and the squeezing characteristic is obtained when the wall thickness of the squeezed body of the container body 1 is 1200 μm or less at the portion where the label is welded. Important for.

Label 5 is made of low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene,
Ethylene propylene copolymer resin, polyolefin resin such as ethylene vinyl acetate copolymer resin, polyamide resin,
A base material layer 5a composed of a film of a synthetic resin such as an ionomer resin, an ABS resin, polyvinyl chloride, or a polyethylene terephthalate resin, or a film obtained by blending a filler such as an inorganic material with the synthetic resin, preferably a stretched film. And a printing layer 5b in which characters or figures are printed on one surface of the base material layer 5a with an oil-based ink or a solvent type ink, and the surface is clear-coated,
The other surface is formed of an adhesive layer 5c made of a low melting point synthetic resin. This label 5 has a thickness of 50 to 10
It is important in the present invention that the thickness is 0 μm. If the thickness is less than 50 μm, it will be difficult to separate the stacked labels one by one, and it will be particularly difficult to arrange the labels in a mold using a label inserter. Conversely, 100
If it exceeds μm, the parison cannot be cooled by the separation mold, the cooling of the parison 14 becomes slow, and the shrinkage of the portion of the squeezed body 3 where the label 5 is adhered becomes larger than that of the other portions. Then, the edge of the label 5 is raised. When the label 5 is left in an atmosphere of 120 ° C. for 10 minutes, the shrinkage is 0 to 5%, and it is important that the shrinkage is equal to or smaller than the shrinkage of the container body 1.

The printing layer 5b formed on one surface of the base material layer 5a of the label 5 is formed by printing characters or figures with oil-based ink or solvent type ink, and then clear-coating the surface. On the other surface, an adhesive layer 5c made of a synthetic resin having a lower melting point than the thermoplastic resin of the container body 1
Is formed and embossed to maintain good peelability between labels.

According to the present invention, the label 5 is selected according to the material of the thermoplastic resin constituting the container body 1, and it is important for the purpose of the present invention that the thickness of the label 5 is in the range of 50 to 100 μm. It is.

When the label 5 is welded to the container body 1,
The fact that the parison 14 is chemically or physically fixed to the label 5 depending on the melting state of the parison 14. here,
The term "chemically" means that the two are integrated into a material by being compatible with each other and melting. Also, physically refers to a material in which the paris 14 is embedded in and fixed to the surface of the label 5 by solidifying the surface of the label 5.

In the present invention, the shrinkage ratio of the label 5 is 1
The shrinkage when left in an atmosphere of 20 ° C. for 10 minutes,
The shrinkage rate of the container body 1 indicates the shrinkage rate of the molded article of the container body 1 with respect to the shape of the cavity 12 of the separation mold 11 when blow molded. The shrinkage of the label 5
Although there is an MD direction and a TD direction orthogonal to the MD direction, in the present invention, the shrinkage rate of the label 5 which is equal to or less than the shrinkage rate of the thermoplastic resin of the container body 1 is two kinds of shrinkage of the MD direction and the TD direction orthogonal thereto. Among the rates, the larger shrinkage rate is defined as the label shrinkage rate.

The thickness of the portion of the present invention where the label is not welded is the thickness of the portion of the squeezed body that is orthogonal to the portion where the label is welded, and is the thickness of the portion near the parting line. Example 1 Polypropylene is used as a base material layer, one side of which is printed with an oil-based ink and a clear coat is applied to the surface to form a print layer, and the other side is embossed with a low melting point resin having a melting point of 60 ° C. 50 μm thick formed as an adhesive layer
Heat shrinkage rate at 20 ° C for 10 minutes is 1.5% in MD direction
And a label having a TD direction of 0.2% was used. The label is affixed to the cavity surface of the split mold having the cavity shaped in the shape of the mayonnaise container, with the printing layer side in contact with the cavity, and vacuum-adsorbed to the mold surface. With the split mold open, a multi-layer parison having a low-density polyethylene as a surface layer and an ethylene vinyl alcohol copolymer resin as an intermediate layer is arranged between the split molds, and the split mold is tightened. A pressurized fluid was blown into the parison to expand the parison, thereby forming the squeezed container of Example 1. In addition, of the labeled squeezed container of Example 1,
The shrinkage ratio of the molded product of the container body with respect to the cavity shape of the mold was 3.0%. The appearance test and deformation test of the squeezed container thus obtained were performed as follows. Table 1 shows the results. Appearance test The obtained labeled squeezed container was visually inspected for wrinkles on the label, and the evaluation was made as follows.

Evaluation A: Beautiful without wrinkles.

Evaluation B: Wrinkles are slightly observed, but do not hinder practical use.

Evaluation C: Wrinkles were generated and the appearance was unsightly. Deformation Test The obtained label of the squeezed container with label and its peripheral shape were visually compared with the shape of the corresponding squeezed body portion of the mold cavity, and the evaluation was as follows.

Evaluation A: A container having a shape similar to the cavity shape of the split mold and having no deformation.

Evaluation B: Label part is inward or outward,
It is slightly deformed.

Evaluation C: The label portion is deformed inward or outward so as to be unsightly. Examples 2 and 3 A squeezed container with a label was molded in the same manner as in Example 1 except that the thickness of the label was changed to 80 μm (Example 2) and 100 μm (Example 3), and the appearance test of the squeezed container with the label was performed. And deformation tests. Table 1 shows the results. Comparative Examples 1 and 2 A squeezed container with a label was formed in the same manner as in Example 1 except that the thickness of the label was changed to 30 μm (Comparative Example 1) and 120 μm (Comparative Example 2), and an appearance test of the squeezed container with the label was performed. And deformation tests. Table 1 shows the results. Comparative Example 3 A squeezed container was formed in the same manner as in Example 1 except that a label having a polypropylene disposed in the base material layer was used. The heat shrinkage of this label after heating at 120 ° C. for 10 minutes was 5.0% in the MD direction and 1.5% in the TD direction. An appearance test and a deformation test of the labeled squeezed container were performed. Table 1 shows the results. In Table 1, the numerical value in parentheses in the column of the non-label portion indicates a value obtained by dividing the thickness of the portion of the squeezed body where the label is not welded by the thickness of the portion where the label is welded. Comparative Example 4 The thickness of the label welding portion of the squeezed body of the container body was set to 15
A squeezed container with a label was formed in the same manner as in Example 1 except that the thickness was set to 00 μm, and an appearance test and a deformation test of the squeezed container were performed. Table 1 shows the results. Examples 4 and 5 Example 1 was the same as Example 1 except that the thickness of the portion of the container body where the label was not welded was 800 μm and 1200 μm.
A squeezed container with a label similar to that described above was molded, and an appearance test and a deformation test of the squeezed container were performed. The results are shown in FIG.

Comparative Example 5 and Comparative Example 6 Example 1 was repeated except that the thickness of the portion of the container body where the label was not welded was changed to 750 μm and 1300 μm.
A squeezed container with a label similar to that described above was molded, and an appearance test and a deformation test of the squeezed container were performed. The results are shown in FIG.

[0031]

[Table 1] It can be seen from Table 1 that the thickness of the label is preferably 50 μm to 100 μm from the viewpoint of appearance and deformation prevention. When the thickness of the label exceeds 100 μm and becomes 120 μm, the label welded to the squeezed body of the squeezed container with labels is wrinkled, and the appearance is deteriorated.
When the thickness is 30 μm, which is thinner than the thickness of 0 μm, the operability of the labels is poor, and a plurality of labels are arranged in an overlapping manner, thereby causing molding failure. Further, when the shrinkage of the label became larger than the shrinkage of the container body, the container body was deformed, and particularly the label portion was deformed inward toward the inside so as to be unsightly. Further, the ratio of the thickness of the portion of the container body where the label is welded to the portion of the container body where the label is welded to the thickness of the portion where the label is not welded is 0.
If it is smaller than 8, orange skin will appear on the label,
A prominence occurs at the end of the label, resulting in poor appearance.
It was found that when it exceeded 2, the container itself was deformed.

[0032]

The present invention is configured as described above.
The following effects are obtained.

A design can be imparted to the squeezed container with label, and a beautifully squeezed container with no wrinkles such as orange skin and no bulge at the edge thereof can be obtained on the label of the squeezed body.

[Brief description of the drawings]

FIG. 1 is a front view showing an entire squeezed container with a label according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing one step of one embodiment of the method for manufacturing a labeled squeezed container of the present invention, showing a state in which a split mold is opened and a molten parison is hung down.

FIG. 3 is an explanatory view showing the steps of one embodiment of the manufacturing method of the present invention and showing the state after pressurized fluid injection.

FIG. 4 is an enlarged sectional view of a label used in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container main body 2 Squeezing opening part 3 Squeezing trunk part 4 Bottom part 5 Label 11 Split mold 12 Cavity 13 Head 14 Parison 15 Vacuum hole

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-139350 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B65D 23/00-25/06 B65C 3 / 26

Claims (2)

(57) [Claims] 1. A squeezing body portion of a thermoplastic resin container body comprising a squeezing body portion, a squeezing opening portion and a bottom portion, having a thickness of 50 to 100 μm and a shrinkage rate of the container body. The following synthetic resin labels are integrally welded at the time of blow molding, and the ratio of the thickness of the portion where the label is not welded to the thickness of the portion where the label of the squeezed body is welded is 0.8 to 1.2. A squeezed container with a label, characterized in that: 2. A label is temporarily fixed to an inner surface of a cavity of a split mold having a cavity for forming a container body including a squeezed body portion, a squeeze opening portion, and a bottom portion which are opened, and heating is performed between the split molds. In a blow molding method of disposing a parison made of a molten thermoplastic resin and then closing the mold, introducing a pressure fluid into the paris, and integrating the label with the container body during molding, the label has a thickness of 50 to 50. A synthetic resin having a shrinkage factor of 100 μm and a shrinkage ratio equal to or less than the shrinkage ratio of the container body is used, and the shape of the parison is squeezed and the label is welded to the thickness of the portion of the body to which the label is welded. A method for producing a squeezed container, wherein the ratio of the thickness of the portion not to be processed is adjusted to be in the range of 0.8 to 1.2.