JP6683040B2 - In-mold label and in-mold label container - Google Patents

Description

  The present invention relates to an in-mold label and an in-mold label container.

  BACKGROUND ART Conventionally, as a cup-shaped container for hermetically packaging various beverages, dessert foods, etc., a cup-shaped container formed by injection molding of plastic is often used because of its good shape retention. Furthermore, in order to improve the design and the light-shielding property, at the time of injection molding of the container, an in-mold label having a base material layer and an adhesive layer composed of a thermoplastic resin is used, and the injection resin is formed on the inner surface of the in-mold label. There is known an in-mold label container obtained by injecting.

JP, 2006-206162, A JP, 9-295383, A

  In Patent Document 1, a substrate made of a synthetic resin single-layer film that can be directly heat-welded to the wall surface of a container is embossed.

  However, in the case of multi-color gravure in-mold labels, when embossing the in-mold labels as in Patent Document 1, a work different from the printing process is required. In this case, the cost increases due to the increase in the number of working steps.

  Further, in Patent Document 2, a white or black heat seal layer made of a thermoplastic resin having a light hiding property is provided on the back surface side of the base material layer.

  However, when a printing layer using a white or black color is provided in addition to the heat seal layer as in Patent Document 2, the number of printing units that can be used in the multi-color printing machine is limited, and thus the usable colors There is a risk that the number of papers will be limited and the designability due to printing will deteriorate. Further, in order to secure the number of colors to be used, it is necessary to pass the in-mold label through the multicolor printing machine again and reprint it. In this case, the cost is increased by increasing the number of printing processes.

  The present invention has been made in consideration of the above points, and provides an in-mold label and an in-mold label container that can reduce costs without providing a white or black printing layer other than the heat-sealing layer. The purpose is to do.

  The present invention is an in-mold label for an in-mold label container, which is adhered to the outer surface of a container body formed by injection molding, wherein a transparent base material layer made of polypropylene is disposed inside the base material layer, and A heat seal print layer adhered to the container body; and a pattern print layer disposed between the base material layer and the heat seal print layer, wherein the heat seal print layer is titanium oxide and chlorinated. Polypropylene, including, the heat seal print layer, when viewed from the base layer side, functions as a base layer for the pattern print layer, the concentration of titanium oxide contained in the heat seal print layer, The in-mold label is characterized by being 5% by weight or more and 28% by weight or less.

  The present invention is the in-mold label, wherein the pattern print layer is a multicolor print layer.

  The present invention is the in-mold label, wherein the concentration of titanium oxide contained in the heat seal printing layer is 15% by weight or more.

  The present invention is an in-mold label container comprising the in-mold label according to the present invention and the container body.

  As described above, according to the present invention, since the heat-sealing print layer contains titanium oxide and the concentration of titanium oxide is 5% by weight or more and 28% by weight or less, the heat-sealing printing layer can be made closer to white. . Further, by making the heat seal print layer close to white, the heat seal print layer functions as a base layer for the pattern print layer when viewed from the base material layer side. For this reason, it is not necessary to separately provide a white print layer in addition to the heat seal print layer as a base layer of the pattern print layer. As a result, the step of printing the white print layer can be omitted as compared with the case where the white print layer is separately provided.

FIG. 1 is a vertical sectional view showing an in-mold label container according to the present embodiment. FIG. 2 is a rear view showing the in-mold label container shown in FIG. 1. FIG. 3 is a development view showing the outer shape of the in-mold label according to the present embodiment. FIG. 4 is a diagram showing a layer structure of the in-mold label shown in FIG. 3.

  Embodiments of the in-mold label and the in-mold label container according to the present invention will be described below with reference to FIGS. 1 to 4. 1 is a vertical cross-sectional view showing the in-mold label container, and FIG. 2 is a rear view of the in-mold label container shown in FIG. 3 is a development view showing the outer shape of the in-mold label, and FIG. 4 is a view showing the layer structure of the in-mold label shown in FIG.

  As shown in FIGS. 1 and 2, the in-mold label container 1 includes a container body 2 formed by injection molding and an in-mold label 10 adhered to the outer surface of the container body 2. Of these, the container body 2 includes a body portion 3, a flange portion 4 provided at an upper end of the body portion 3, a bottom portion 5 provided at a lower end of the body portion 3, and a leg provided at a peripheral edge of the bottom portion 5 and protruding downward. And a part 6.

  An in-mold label 10 for an in-mold label according to the present invention is adhered to the outer peripheral surface side of the body portion 3. A stack rib 8 is provided on the lower portion of the body 3.

  Then, the portion of the body portion 3 excluding the in-mold label 10, the flange portion 4, the bottom portion 5, and the leg portion 6 are injection resin obtained by injecting the injection resin into an injection molding die (not shown). It consists of part 7. Although the leg portion 6 is provided on the extension of the body portion 3, the in-mold label 10 may reach the leg portion 6.

  Next, the portion of the body 3 excluding the in-mold label 10, the injection resin material of the injection resin portion 7 forming the flange portion 4, the bottom portion 5 and the leg portion 6, and the in-mold label 10 will be described.

  As the injection resin material forming the injection resin portion 7, a synthetic resin such as polyethylene, polyethylene terephthalate, polystyrene or polypropylene can be used.

  Next, the in-mold label 10 will be described with reference to FIGS. 3 and 4. As shown in FIG. 3, the in-mold label 10 has a fan shape, and the upper and lower corners of both ends 10a and 10b of the in-mold label 10 are chamfered in a small R shape.

  As shown in FIG. 1, it is preferable that the length of the in-mold label 10 in the height direction slightly protrudes from the flange portion 4 above the body portion 3 and reaches the middle portion of the leg portion 6 below. In the circumferential length of the in-mold label 10, as shown in FIG. 2, a gap 10A having a width of about 0.2 to 2.0 mm is formed between the opposite ends 10a, 10b which are butted to each other. The length is preferably about the same. By forming the in-mold label 10 as described above, the in-mold label 10 is inserted into a predetermined position of a female die of an injection molding die (not shown) and fixed by vacuum suction, and after the die is closed, the injection resin is applied to the bottom of the female die. It is possible to prevent defects such as overlapping portions, turning up, and wrinkles from occurring in the in-mold label 10 when the liquid is injected from the gate at the center of the. At this time, the injection resin can be smoothly injected, and the in-mold label 10 and the injection resin can be integrally molded.

  Next, the in-mold label 10 according to the present embodiment will be described. As shown in FIG. 4, the in-mold label 10 includes a base material layer 11, a heat seal printing layer 12 disposed inside the base material layer 11, and a space between the base material layer 11 and the heat seal printing layer 12. And a pattern print layer 13 arranged. Among these, the base material layer 11 includes a transparent layer made of polypropylene. More specifically, a stretched polypropylene film is used as the base material layer 11. Further, the thickness of the base material layer 11 is set to 60 μm.

  Further, on the outside of the base material layer 11, a matte matte overprint layer (matte OP layer) 14 that protects the base material layer 11 is provided. As the matte overprint layer 14, an acrylic resin matte varnish can be used.

  The heat seal printing layer 12 is a layer that is adhered to the container body 2 when the in-mold label container 1 is injection molded. The heat seal print layer 12 contains titanium oxide and chlorinated polypropylene. The concentration of titanium oxide contained in the heat seal printing layer 12 is 5% by weight or more and 28% by weight or less.

  Here, when the concentration of titanium oxide contained in the heat seal print layer 12 is less than 5% by weight, the heat seal print layer 12 does not exhibit the effect as the base layer of the pattern print layer 13, and the base material layer 11 side. There is a problem that the designability of the pattern print layer 13 when viewed from above is deteriorated. On the other hand, when the concentration of titanium oxide contained in the heat seal print layer 12 exceeds 28% by weight, the adhesiveness between the pattern print layer 13 and the heat seal print layer 12 deteriorates, and the ink is printed on the pattern print layer 13. There is a problem that printing defects such as omission occur. On the other hand, according to the present embodiment, since the concentration of titanium oxide contained in the heat seal print layer 12 is set to 5% by weight or more, the color of the heat seal print layer 12 can be brought close to white. As a result, the heat seal print layer 12 functions as a base layer for the pattern print layer 13 when viewed from the base material layer 11 side, and the designability can be improved. Further, since the concentration of titanium oxide is set to 28% by weight or less, it is possible to suppress the decrease in the adhesiveness between the heat seal printing layer 12 and the pattern printing layer 13. Therefore, the occurrence of printing defects can be reduced. Furthermore, the concentration of titanium oxide is preferably 15% by weight or more. By setting the concentration of titanium oxide to 15% by weight or more in this way, the color of the heat seal printing layer 12 can be made closer to white. Thereby, the punching register mark formed by the pattern print layer 13 can be made conspicuous. Therefore, when the in-mold label 10 is punched into the shape shown in FIG. 3, the accuracy of registration can be improved. Further, the printing register mark formed by the pattern print layer 13 can be made conspicuous. The punching register mark and the printing register mark will be described later. As the heat seal printing layer 12, a chlorinated polypropylene resin-based ink can be used. Further, since the heat-seal printing layer 12 is a layer that is bonded to the injection resin, it is preferable to include the same material as the injection resin.

    The heat seal printing layer 12 and the pattern printing layer 13 are formed by a plurality of printing units of a multicolor printing machine, and the pattern printing layer 13 is printed in a plurality of colors. As the pattern printing layer 13, an ink having a normal pigment can be used, and for example, a urethane resin ink can be used.

  Next, a method of manufacturing the in-mold label 10 will be described.

  First, a transparent base material layer 11 made of a stretched polypropylene film is prepared.

  Next, the pattern printing layer 13 is formed by laminating on the base material layer 11. In this case, the pattern printing layer 13 is formed using a plurality of printing units (not shown) of a multicolor printing machine (multicolor gravure printing machine, not shown). That is, the multi-color printing machine includes a plurality of printing units that print different colors on the base material layer 11 that is continuously conveyed. In this case, the first printing unit is the first color printing unit of the pattern printing layer 13, the second printing unit is the second color printing unit, and the third printing unit is the third color printing unit. .

  For example, when the multicolor printing machine has nine printing units, the pattern printing layer 13 is printed on the base material layer 11 by the first to seventh printing units. Further, when the printing unit prints the pattern printing layer 13, the registration mark is provided on the pattern printing layer 13. The register mark includes a printing register mark for multicolor printing and a punching register mark used for registering when the in-mold label 10 is punched. Of these, each printing unit provides a printing register mark together with the pattern for each color of the pattern printing layer 13. Then, registration is performed when the pattern printing layer 13 is formed by the printing registration marks provided for each color of the pattern printing layer 13. Further, the punching register mark does not have to be provided for each color of the pattern printing layer 13, and the punching register mark can be provided by one printing unit.

  Next, the heat-seal printing layer 12 is laminated and formed on the pattern printing layer 13 printed in a plurality of colors. In this case, the heat seal printing layer 12 is changed to the pattern printing layer 13 by the printing unit (for example, the eighth printing unit) next to the printing unit (for example, the seventh printing unit) where the pattern printing layer 13 is printed last. It is formed by stacking on top. As described above, the concentration of titanium oxide contained in the heat seal printing layer 12 is 5% by weight or more and 28% by weight or less. This allows the heat seal printing layer 12 to be close to white. Therefore, it is possible to omit the white printing step which functions as a base layer of the pattern printing layer 13 in the printing step of the pattern printing layer 13. In addition, the amount of white ink used can be reduced as compared with the case where a white solid layer of white ink is laminated on the pattern printing layer 13.

  Next, the mat overprint layer 14 is formed by laminating on the base material layer 11. At this time, the base material layer 11 and the pattern printing layer are provided in the printing unit (the last printing unit, for example, the ninth printing unit) next to the printing unit (for example, the eighth printing unit) that forms the heat seal printing layer 12. Before the laminate of 13 and the heat-seal printing layer 12 enters, the laminate is inverted once. Next, by the next printing unit, the matte overprint layer 14 is laminated and formed on the base material layer 11.

  After that, the laminate of the mat overprint layer 14, the base material layer 11, the pattern printing layer 13, and the heat seal printing layer 12 is dried in the drying step, and then the punching register mark provided on the pattern printing layer 13 is used. The in-mold label 10 is obtained by punching with a punching device (not shown).

  As described above, according to the present embodiment, the concentration of titanium oxide contained in the heat seal printing layer 12 is 15% by weight or more and 28% by weight or less, so that the heat sealing print layer 12 can be made closer to white. . This makes it possible to omit the white printing step which functions as a base layer of the pattern printing layer 13 in the printing step of the pattern printing layer 13. Therefore, the number of colors used in the printing process of the pattern printing layer 13 can be suppressed, and the printing process can be completed by one printing process by one multicolor printing machine. That is, it is not necessary to pass the in-mold label 10 again through a separate multicolor printer to reprint in order to secure the number of colors used for the pattern printing layer 13. Therefore, the number of printing steps does not increase, and the cost increase can be suppressed. As a result, the manufacturing process can be simplified and the cost can be reduced.

  Further, in the printing process of the pattern printing layer 13, the white printing process functioning as a base layer of the pattern printing layer 13 can be omitted, and more multicolor printing can be performed on the pattern printing layer 13. Further, the white heat seal print layer 12 functions as a base layer for the pattern print layer 13 when viewed from the base material layer 11 side as described above. This can improve the design.

  Further, since the concentration of titanium oxide contained in the heat seal print layer 12 is preferably 15% by weight or more, the color of the heat seal print layer 12 can be brought close to white. As a result, the register mark provided on the pattern print layer 13 can be made conspicuous. Therefore, the accuracy of registration when punching out the in-mold label 10 can be improved.

  Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the description of the following examples unless it exceeds the gist.

(Example 1)
As Example 1, an in-mold label 10 having the following configuration was produced using a multicolor printing machine including nine printing units.
(Outside) Matt overprint layer / base material layer (60 μm) / pattern printing layer (7 layers) / heat seal printing layer (titanium oxide content 28% by weight)
In this case, as the base material layer 11, the base material layer 11 made of a stretched polypropylene film having a thickness of 60 μm was used. Next, on the base material layer 11, seven pattern printing layers 13 composed of printing layers of seven colors were formed using urethane resin-based ink. Next, the heat seal printing layer 12 was formed on the pattern printing layer 13 using a chlorinated polypropylene resin ink. The heat seal printing layer 12 contains 28% by weight of titanium oxide. Then, the matte overprint layer 14 was formed on the base material layer 11 on the side opposite to the side on which the pattern print layer 13 was laminated.

  Then, the appearance of the pattern print layer 13 when viewed from the base material layer 11 side, the adhesiveness between the pattern print layer 13 and the heat seal print layer 12, and the number of printing steps were evaluated. The results are shown in Table 1.

(Example 2)
As Example 2, an in-mold label 10 was produced in the same manner as in Example 1, except that the titanium oxide content was changed. That is, as Example 2, a multicolor printing machine including nine printing units was used to produce an in-mold label 10 having the following configuration.
(Outside) Mat overprint layer / base material layer (60 μm) / pattern print layer (7 layers) / heat seal print layer (titanium oxide content 15% by weight)
In this case, as the base material layer 11, the base material layer 11 made of a stretched polypropylene film having a thickness of 60 μm was used. Next, on the base material layer 11, seven pattern printing layers 13 composed of printing layers of seven colors were formed using urethane resin-based ink. Next, the heat seal printing layer 12 was formed on the pattern printing layer 13 using a chlorinated polypropylene resin ink. The heat seal printing layer 12 contains 15% by weight of titanium oxide. Then, the matte overprint layer 14 was formed on the base material layer 11 on the side opposite to the side on which the pattern print layer 13 was laminated. Then, the evaluation was performed in the same manner as in Example 1. Table 1 shows the results.

(Comparative Example 1)
As Comparative Example 1, an in-mold label 10 was manufactured in the same manner as in Example 1 except that the titanium oxide content was changed. That is, as Comparative Example 1, an in-mold label 10 having the following configuration was produced using a multicolor printing machine including nine printing units.
(Outside) Mat overprint layer / base material layer (60 μm) / pattern print layer (7 layers) / heat seal print layer (titanium oxide content 1% by weight)
In this case, as the base material layer 11, the base material layer 11 made of a stretched polypropylene film having a thickness of 60 μm was used. Next, on the base material layer 11, seven pattern printing layers 13 composed of printing layers of seven colors were formed using urethane resin-based ink. Next, the heat seal printing layer 12 was formed on the pattern printing layer 13 using a chlorinated polypropylene resin ink. The heat seal printing layer 12 contains 1% by weight of titanium oxide. Then, the matte overprint layer 14 was formed on the base material layer 11 on the side opposite to the side on which the pattern print layer 13 was laminated. Then, the evaluation was performed in the same manner as in Example 1. Table 1 shows the results.

(Comparative example 2)
As Comparative Example 2, an in-mold label 10 similar to that of Example 1 was produced except that the content of titanium oxide and the number of pattern printing layers 13 were changed. That is, as Comparative Example 2, an in-mold label 10 having the following configuration was produced using a multicolor printing machine including nine printing units.
(Outside) Matt overprint layer / base material layer (60 μm) / pattern print layer (8 layers) / heat seal print layer (titanium oxide content 0% by weight)
In this case, as the base material layer 11, the base material layer 11 made of a stretched polypropylene film having a thickness of 60 μm was used. Next, on the base material layer 11, eight pattern printing layers 13 composed of printing layers of eight colors were formed using urethane resin-based ink. That is, a white solid layer of white ink was added to the pattern printing layers 13 of Examples 1 and 2 and Comparative Example 1 to form the pattern printing layer 13 of Comparative Example 2. Next, the heat seal printing layer 12 was formed on the pattern printing layer 13 using a chlorinated polypropylene resin ink. The heat seal print layer 12 does not contain titanium oxide. Then, the matte overprint layer 14 was formed on the base material layer 11 on the side opposite to the side on which the pattern print layer 13 was laminated. Then, the evaluation was performed in the same manner as in Example 1. Table 1 shows the results.

  In Table 1, ◯ indicates that the pattern print layer 13 looks good when viewed from the base material layer 11 side, and that the adhesiveness between the pattern print layer 13 and the heat seal print layer 12 is good. Alternatively, it indicates that the printing process can be completed by one printing process by one multicolor printing machine. On the other hand, the mark x indicates that the pattern printing layer 13 does not look good when viewed from the base material layer 11 side, or the printing process cannot be completed by one printing process using one multicolor printing machine. It is shown that. When the concentration of titanium oxide contained in the heat seal print layer 12 was 30% by weight or more, the adhesion between the pattern print layer 13 and the heat seal print layer 12 was poor, and printing failure occurred. . Further, when the concentration of titanium oxide contained in the heat seal print layer 12 is lower than 5% by weight, the heat seal print layer 12 does not exhibit the effect as the base layer of the pattern print layer 13 and the base material layer. The appearance of the pattern printing layer 13 when viewed from the 11 side was poor.

  As shown in Table 1, by setting the concentration of titanium oxide contained in the heat-seal printing layer 12 to 15% by weight or more and 28% by weight or less, pattern printing when viewed from the base material layer 11 side. It was confirmed that the appearance of the layer 13 and the adhesiveness between the pattern printing layer 13 and the heat seal printing layer 12 could be improved. In addition, by omitting the white printing step that functions as a base layer of the pattern printing layer 13 in the printing step of the pattern printing layer 13, the number of colors used in the printing step of the pattern printing layer 13 is suppressed, and 9 printing units It was confirmed that the printing process could be completed by one printing process with one multicolor printing machine equipped with.

1 in-mold label container 2 container body 10 in-mold label 11 base material layer 12 heat seal printing layer 13 picture printing layer

Claims (4)

In-mold label for an in-mold label container that is adhered to the outer surface of a container body molded by injection molding,
A transparent base material layer made of polypropylene,
A heat seal printing layer disposed inside the base material layer and adhered to the container body,
A pattern printing layer disposed between the base material layer and the heat seal printing layer,
The heat seal print layer contains titanium oxide and chlorinated polypropylene,
The heat seal print layer functions as a base layer for the pattern print layer when viewed from the base material layer side,
The in-mold label, wherein the concentration of titanium oxide contained in the heat seal printing layer is 5% by weight or more and 28% by weight or less.   The in-mold label according to claim 1, wherein the pattern print layer is a multicolor print layer.   The in-mold label according to claim 1 or 2, wherein the concentration of titanium oxide contained in the heat seal printing layer is 15% by weight or more.   An in-mold label container comprising the in-mold label according to any one of claims 1 to 3 and the container body.

Images