JP2012012019A - Injection molding composite container and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injection molding composite container which includes a label in resin material, can be efficiently manufactured even when contents printed onto the label are changed, and is capable of clearly visualizing the contents printed onto the label from the outside or the inside of the container.SOLUTION: The injection molding composite container (20) comprises a first resin material part (21), a second resin material part (22) and the label (23) included between the first resin material part and the second resin material part, wherein the label has a coated layer formed by fixing a digital print onto at least one surface and both surfaces of the label are integrally melt-stuck to respective resin material parts.

Description

  The present invention relates to a resin container for containing food, medicine, cosmetics, and the like and a method therefor. More specifically, it is a resin container containing a label, the appearance is remarkably improved, there is no concern of contaminating the contents contained in the container, and the label and the resin are integrated. In particular, the present invention relates to a container that can respond to a demand for rapidly manufacturing a small number of various types of containers, and can easily give variable information on the label.

Conventionally, an in-mold molding method is known as a method of manufacturing a resin molded body with a label attached thereto by integral molding. In this method, a label or a blank is attached to the inner wall of the mold in advance, and a molding resin such as polyethylene resin or polypropylene resin is melted and supplied directly into the mold, and the resin is shaped in the mold. In addition, a label is attached to the molten resin (see, for example, Patent Document 1 and Patent Document 2). In addition, such a label attached in a mold is called an in-mold label (IML).
As such an in-mold label, a gravure-printed resin film, offset multicolor-printed synthetic paper (see, for example, Patent Document 3 and Patent Document 4), or a high-pressure low-density polyethylene on the back surface of an aluminum foil, An aluminum label or the like obtained by laminating an ethylene / vinyl acetate copolymer and gravure printing on the surface of the foil is known.

Such an in-mold label is usually mounted and fixed using suction or static electricity on the inner wall of a female mold that forms the outer periphery of the molded body, and then a molten resin is supplied into the mold to form the molded body. In order to integrate with this, it has stuck on the outer periphery of the molded object.
On the other hand, for the purpose of further improving the design, various attempts have been made to arrange the label not on the outside of the molded body but on the inside so that the label can be visually recognized through the transparent or opaque molded body.

For example, Patent Documents 5 to 8 describe a composite container in which a label (printed material, decorative film) is loaded (sandwiched, arranged, embedded) between containers having a double structure including an inner container and an outer container. . These containers are visible from the outside through an outer container whose label is transparent or translucent, and are supposed to provide an appearance suitable for luxury products.
However, in the present invention, the label is not fused to the outer container, but is only in contact with it and is not integrated. Although the label contents can be visually recognized from the appearance of the container, there is an air layer between them, and light reflection and diffraction occur individually at the interface between the inner surface of the container and the surface of the label. The decoration such as printing was blurred due to the diffusion of light, and there was a problem that the sense of unity between the container and the label was poor. In order to enhance the sense of quality, it is desirable that the outer container and the label are fused and integrated, but this has not been realized. Furthermore, the inventions of Patent Documents 7 and 8 are not easy to cause displacement or dropping because the label moves freely until the inner container is formed by parison blow molding and the label is fixed. There was a problem that it was not stable.

  On the other hand, as an invention for arranging a label on the inside of a container and integrating it, methods of Patent Documents 9 to 11 are seen. These disclose an application invention of an in-mold molding method in which a label is inserted into a mold in advance and the label is attached to the inside of the molded body to be integrated.

Patent Document 9 describes a method for manufacturing a labeled container in which a heat-shrinkable label is heat-shrinked in accordance with the shape of a male mold, and then closed with a female mold and injection-molded. ing. According to this method, it is possible to obtain a container in which the label is integrated without misalignment, but this method has few choices for the label material, and in terms of manufacturing method, the label is installed at a fixed position of the male mold, Since it takes time to heat-shrink, the shot cycle for forming one container becomes very long, so the productivity is not good.
Above all, the problem of the container obtained in Patent Document 9 is that there is a safety concern because the contents directly touch the label. In view of consumer demands for product safety in recent years, for containers that contain contents used directly on the human body, such as food, medicine, and cosmetics, the contents should be in contact with the resin container body for a long period of time. On the other hand, it is preferable that the label is disposed between the double containers and isolated from the contents as in the above-described Patent Documents 5 to 8. In the aspect of Patent Document 9, even if the printing surface is not inside the container, the possibility of elution of printing ink from the label end face cannot be avoided. This is because the invention cannot control the design of the label. Furthermore, the content component (oil) may permeate into the label and swell to deteriorate the appearance of the container, or the label itself may peel off and come into contact with the content.

  Patent Document 10 describes a method for forming a cylindrical container in which an in-mold label that has been fixed to the outer wall of a mold in advance is pushed inward by the flow of inflow resin, and finally the label is attached to the inner peripheral surface. is there. However, this method avoids problems such as misalignment during label movement, label perforation due to resin pressure, printing flow, product appearance deterioration due to inflowing resin label wrapping around the front and back, and yield deterioration. Absent.

  In Patent Document 11, a core mold having a label attached to the outer peripheral surface is inserted into a cup-shaped primary molded product, and the primary molded product is shrunk so as to be in close contact with the core mold by heating. There is a description of a method for forming a cup-shaped container that adheres to the inner peripheral surface of the container. However, this method also requires time to place the label at a fixed position of the core mold and heat-shrink the container. Therefore, the shot cycle for forming one container becomes very long, so that productivity is increased. Not good. Further, in Patent Documents 10 and 11, since the label is in direct contact with the contents as in Patent Document 9, the safety concerns are not solved.

  In addition, the invention described in Patent Documents 9 to 11 in which a label is arranged on the inside of a container and integrated with the label is not realized because productivity is not good. Combined composite containers have not yet been realized. In particular, in the methods described in Patent Documents 5 to 8, in which the inner container and the outer container are individually made and combined, or in the method in which the outer container is made first and then the inner container is blow molded, the label is integrated with the outer container. The problem that cannot be fixed, the problem that the label cannot be securely fixed at a fixed position, or the troublesome, time-consuming and unrealistic work process still cannot be avoided.

In addition to the above technical field, Patent Document 12 describes, in relation to the tableware manufacturing method, the step of injection molding the inner member and the position corresponding to the injection port when the outer member is injection molded on the back surface of the inner member. A process of attaching a sheet that can withstand the heat and pressure of the molten resin material at the time of injection molding of the outer member by using an adhesive or installing it in a recess, and an outer member on the outer side of the inner member to which this sheet is attached There is a description of a tableware manufacturing method comprising a step of injection molding.
However, the invention of Patent Document 12 is not integrated with the resin material of the inner member and the outer member on both sides of the sheet to be inserted, so as in the inventions of Patent Documents 5 to 8, There was a problem that the sense of unity between the container and the label was poor. In addition, the invention of Patent Document 12 is only required to be disposed at a position corresponding to the injection port when the outer member is injection-molded, and this point is also accepted in the market. It is insufficient from the viewpoint of improving the appearance.
Furthermore, from the viewpoint of the manufacturing method, it is complicated because it includes a separate step of once molding the inner member and then attaching a sheet to the back surface of the inner member.

In Patent Document 13, a molded product made of a first transparent resin having a pattern formed on one side is disposed on a female mold for insert molding so that the pattern side faces the male mold, and the mold is closed. After that, the second transparent resin is injected between the molded product made of the first transparent resin and the male mold so that the design is sandwiched between the first transparent resin and the second transparent resin. There is a description of a method for producing a molded article with a pattern.
However, the invention of Patent Document 13 originally relates to a method of manufacturing a molded article with a pattern suitable as an emblem representing a manufacturer name or a product name of home appliances or automobiles. When the present invention is diverted as a method for manufacturing a container containing a label, an outer container having a label disposed inside the container is first obtained as a molded product made of a first transparent resin, and then the first molded product is a female mold. A second transparent resin is injected into the inside as a part of the inner container to produce an inner container, and a container in which the design is sandwiched between the first transparent resin and the second transparent resin is manufactured.
Here, in order to mold the first molded product in which the label is arranged inside the container, techniques such as the inventions described in Patent Documents 9 to 11 must be used, and implementation is difficult. Further, after forming the outer container, according to the manufacturing method in which the inner container is formed by injection molding on the inner side, the label portion which is an interface with the outer container is lifted, and the container in which the label and the resin material are integrated is obtained. There is a problem that it cannot be obtained.

  For the purpose of manufacturing a container in which a label and a resin material are integrated, Patent Document 14 proposes a new method for manufacturing an injection-molded composite container. In this manufacturing method, (1) a label is placed and fixed on the inner wall of a female mold, the mold is closed, and then the inner resin material is injected into the female mold and molded to fuse the label to the outside. Form the inner resin material part, (2) Close the mold with the inner resin material and the second female mold so as to completely enclose the label on the inner resin material part, and inject and mold the outer resin material Thus, the outer resin material part is formed so as to cover the label on the inner resin material part. According to this method, it is described that a composite container in which inner and outer resin materials and labels are integrated can be manufactured.

JP 58-069015 A Japanese Patent Laid-Open No. 01-125225 Japanese Patent Publication No. 02-007814 Japanese Patent Laid-Open No. 02-084319 Japanese Patent Laid-Open No. 08-301262 JP 2006-062751 A JP 2000-142684 A JP 2001-287260 A JP 06-016992 A Japanese Patent Laid-Open No. 11-245260 JP 2006-096012 A JP 58-096533 A JP 09-011275 A JP 2009-263006 A

  Printing methods such as sheet-fed offset printing, rotary offset printing, gravure printing, flexographic printing, letter press printing, and screen printing can be applied to the labels used in the method of Patent Document 14. In order to perform these printing methods, it is necessary to prepare a plate making or printing plate (lithographic plate, letterpress plate, stencil plate, etc.). Therefore, these printing methods take time to obtain the final printed matter, and the cost tends to be expensive unless the lot amount (number of copies) is large to some extent. For this reason, the method of patent document 14 is an advantageous method when manufacturing the composite container of the amount gathered to some extent using the label by which the same printing was made.

  However, in recent years, demands for smaller lots and more products are becoming stronger, as represented by the emphasis on local colors and the rise of private brands. In addition, brand owners are demanding that a new container for storing a product be manufactured in a shorter period of time in order to realize a quick release of the product. In order to meet these demands, container manufacturers are forced to produce a large number of labels or multiple labels for use in advance, so they always bear inventory risk and are timely. However, it was not possible to sufficiently use efficient materials.

  Further, in the above conventional printing method, there is a problem that it is not realistic to give variable information (for example, manufacturing date, expiration date, expiry date, lot number, serial number, etc. related to the contents) on the label. . In other words, if different information is to be given to each label, it is necessary to prepare a plate making or a printing plate for each information, and it must be said that industrial applicability is low in view of cost and labor. Therefore, if variable information is to be displayed, the container itself has to be dealt with by laser printing (engraving). If variable information can also be printed on the label, it is advantageous because it can improve manufacturing efficiency and reduce manufacturing costs. However, a practical manufacturing method for composite containers that can achieve this has been developed. It wasn't.

  The present invention has been made in view of the above problems. An object of the present invention is a composite container containing a label in a resin material, which can be efficiently manufactured even if the content printed on the label changes, and the label is printed from the outside or inside of the container. The object is to provide a content that can be clearly seen. Another object of the present invention is to provide a composite container that is free from safety concerns with respect to the contents put in the container. It is another object of the present invention to provide a method capable of producing the above composite container quickly and with a high yield even when the printing contents are changed for every few labels.

  As a result of intensive studies to solve the above problems, the present inventors have found that if a composite container is produced using a label provided with a specific coat layer, the desired performance can be achieved, The present invention described below has been completed.

[1] An injection-molded composite container comprising a first resin material part, a second resin material part, and a label enclosed between the first resin material part and the second resin material part. ,
The label has a coat layer in which digital printing is fixed on at least one surface thereof, and both surfaces of the label are fused and integrated with the resin material portions. Injection molded composite container.
[2] At least one selected from the group consisting of a polyethyleneimine resin, a polyamide polyamine resin, a polyvinyl alcohol resin, a styrene-butadiene copolymer resin, and a vinyl chloride-vinyl acetate copolymer resin as the binder layer is used as a binder resin. The injection-molded composite container according to [1], comprising:
[3] The label is obtained by digitally printing on the coat layer by at least one method selected from the group consisting of a dry electrophotographic system, a wet electrophotographic system, and an inkjet system. The injection molded composite container according to [1] or [2].
[4] The injection-molded composite container according to any one of [1] to [3], wherein the label has the coat layer on both surfaces thereof.
[5] The label according to any one of [1] to [3], wherein the label has the coat layer on one side and a heat seal layer on the other side. The injection-molded composite container described.
[6] The heat seal layer is a low density to medium density high-pressure polyethylene, linear linear polyethylene, ethylene / α-olefin copolymer, propylene / α-olefin copolymer, ethylene / vinyl acetate copolymer, Includes at least one selected from the group consisting of ethylene / acrylic acid copolymers, ethylene / acrylic acid alkyl ester copolymers, ethylene / methacrylic acid alkyl ester copolymers, and metal salts of ethylene / methacrylic acid copolymers The injection-molded composite container as described in [5], wherein
[7] The first resin and the second resin material are each independently a polyolefin resin, a polyester resin, a styrene resin, an ethylene-vinyl acetate resin, a polyamide, a polycarbonate, a polyvinyl chloride, a polyoxymethylene, a poly Any one of [1] to [6], which is a resin composition comprising at least one thermoplastic resin selected from the group consisting of methyl methacrylate, polymethacrylstyrene, polyallyl sulfone, and ionomer An injection-molded composite container according to claim 1.
[8] The first resin material is high density polyethylene, medium density polyethylene, polypropylene, poly (4-methylpent-1-ene), polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene succinate, polylactic acid, From the group consisting of polystyrene, styrene-acrylonitrile resin, acrylonitrile-butadiene-styrene resin, ethylene-vinyl acetate resin, polyamide, polycarbonate, polyvinyl chloride, polyoxymethylene, polymethyl methacrylate, polymethacryl styrene, and polyallyl sulfone A resin composition comprising at least one selected thermoplastic resin, and the second resin material is made of high-density polyethylene, medium-density polyethylene, polypropylene, poly (4-methylpe). 1-ene), elastomer, ionomer, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene succinate, polylactic acid, amorphous polyethylene terephthalate, polystyrene, styrene-acrylonitrile resin, acrylonitrile-butadiene-styrene resin, ethylene- At least one heat selected from the group consisting of vinyl acetate resin, polyamide, polycarbonate, polyvinyl chloride, polyoxymethylene, polyvinyl alcohol, polybutene, polymethyl methacrylate, polymethacrylstyrene, polyarylate, and polyallylsulfone The injection-molded composite container according to any one of [1] to [6], which is a resin composition made of a plastic resin.
[9] The injection molded composite container according to any one of [1] to [8], wherein a resin composition made of the same resin material is used for the first resin material and the second resin material. .
[10] The injection-molded composite container according to any one of [1] to [8], wherein the first resin material and the second resin material have different resin compositions.
[11] As described in any one of [1] to [10], the first resin material portion is formed by injection molding and has a shape of a container having a fitting portion with a lid. Injection molded composite container.
[12] The injection-molded composite container of [11], wherein the label is disposed along an outer peripheral wall of the first resin material portion having a container shape.
[13] The injection-molded composite container according to any one of [1] to [12], wherein at least one of the first resin material part or the second resin material part is transparent.
[14] The injection-molded composite container of [13], wherein digital printing on the coat layer is visible through the resin material part.
[15] The injection-molded composite container according to any one of [1] to [14], wherein the label is not perforated.
[16] The injection-molded composite container according to any one of [1] to [15], which is not further laminated on the printing surface of the label (the printing surface is the surface of the label).
[17] The injection-molded composite container according to any one of [1] to [16], wherein the base material of the label is composed of a polyolefin film or a polyester film.
[18] The injection-molded composite container according to any one of [1] to [17], wherein the front surface and the back surface of the base material of the label are made of different materials.

[19] A method for manufacturing an injection-molded composite container comprising a first resin material part, a second resin material part, and a label included between the first resin material part and the second resin material part Because
(1) A step of performing digital printing on the coat layer of the label having a coat layer on at least one surface;
(2) The label is formed by injecting and molding the first resin material into the first mold after the label is placed and fixed on the inner wall of the first mold on the female mold side and the mold is closed. Forming a fused first resin material part; and
(3) The mold is closed between the first resin material part as a male mold or a part of the male mold and the second mold as a female mold so as to completely enclose the label on the first resin material part. A method for producing an injection-molded composite container comprising: forming a second resin material portion so as to cover a label on the first resin material portion by injecting and molding the second resin material .
[20] The method according to [19], wherein a plurality of composite containers having different print contents are finally manufactured by digitally printing a plurality of labels while changing the print contents in the step (1). Manufacturing method of injection-molded composite container.
[21] The method for manufacturing an injection-molded composite container according to [20], wherein the change of the print content is performed by controlling an electrical signal designating the print content.
[22] A coat layer is formed only on one side of the label. In the step (2), a surface opposite to the coat layer forming side of the label is formed on the inner wall of the first mold on the female mold side. It arrange | positions so that it may contact | connect, The manufacturing method of the injection molding composite container as described in any one of [19]-[21] characterized by the above-mentioned.
[23] The method for producing an injection-molded composite container according to any one of [19] to [21], wherein a coat layer is formed on both surfaces of the label.
[24] The method for producing an injection-molded composite container according to any one of [19] to [23], wherein the digital printing is performed by a dry electrophotographic method or a wet electrophotographic method.
[25] The method for producing an injection-molded composite container according to any one of [19] to [23], wherein the digital printing is performed by an inkjet method.
[26] The method according to any one of [19] to [25], wherein in the step (1), the first resin material portion is formed into a shape of a container having a fitting portion with a lid. Manufacturing method of the injection molded composite container.
[27] The method for manufacturing an injection-molded composite container according to any one of [19] to [26], wherein the second resin material part is formed outside the first resin material part.
[28] The method for producing an injection-molded composite container according to any one of [19] to [27], wherein the second resin material part is formed into a container shape.
[29] The method for producing an injection-molded composite container according to any one of [19] to [28], wherein the first resin material and the second resin material have different resin compositions.
[30] The injection-molded composite container according to any one of [19] to [28], wherein the first resin material and the second resin material are resin compositions made of the same resin material. Manufacturing method.

  The composite container of the present invention has a markedly improved appearance because the label contained in the resin material constituting the container can be clearly seen through the resin material portion. Further, since the label does not directly touch the contents of the container, there is no safety concern for the contents. In particular, in the label constituting the composite container of the present invention, the color material for digital printing is firmly fixed by having a specific coating layer, and the resin material part melted at the time of molding the composite container is in contact with the printing surface. However, the color material will not be washed away. In addition, since the coating layer has extremely good fusion with the resin material portion, it can be integrated with the resin material portion without further laminating a heat seal layer, a laminate film or the like on the printed surface. For this reason, according to the present invention, it is possible to efficiently produce a composite container having various print contents with fewer steps, and the industrial utility can be remarkably enhanced.

It is sectional drawing which shows one embodiment of the 1st resin material part (inner side container) used for the composite container of this invention. It is sectional drawing which shows one embodiment of the composite container of this invention.

Below, the composite container of this invention is demonstrated in detail. The description of the constituent elements described below may be made based on typical embodiments of the present invention, but the present invention is not limited to such embodiments.
In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

Resin material (first resin material part)
The first resin material portion of the composite container of the present invention is formed by injection molding of a resin material and constitutes a part of the resin material of the composite container. The first resin material portion preferably has the shape of a container, and more preferably has a structure serving as a main body of the composite container. It is preferable that the first resin material portion has a structure that becomes an inner container of the composite container. The inner container here has at least a bottom part and a side wall part, and is a container in contact with the contents to be put in the composite container. It can take various shapes such as a cylinder, cup, or bottle with an open top, and a fitting part such as a screw fitting for fitting the lid is formed on the upper end of the pipe. May be. There is no restriction | limiting in particular about thickness, A thing which thickness changes continuously in a side wall part may be sufficient.

  The first resin material part may be transparent, translucent or opaque. When making translucent or opaque, an existing filler may be used. Further, the first resin material part may be natural or colored. In the case of coloring, an existing colorant may be used. In order to make it possible to visually recognize the label contained in the composite container from the inside of the composite container, it is necessary to use a transparent or translucent resin material for the first resin material portion serving as the inner container. For example, by making the outer container opaque and the inner container transparent, the label cannot be visually recognized through the outer container, but the print on the label can be visually confirmed through the inner container, thereby improving design and design. Can do. It is also possible to make the information and decoration inside the label visible only by opening the lid or using the opaque contents of the container to some extent. For example, security information to prevent counterfeiting and counterfeiting, and prizes Or fortune. As long as the decoration on the label can be visually recognized from the outside of the composite container, the first resin material portion serving as the inner container does not necessarily need to be transparent or translucent, and can be opaque.

  Examples of the resin material forming the first resin material portion include injection-moldable polyolefin resins such as high-density polyethylene, medium-density polyethylene, polypropylene, and poly (4-methylpent-1-ene); polyethylene terephthalate, polybutylene Polyester resins such as terephthalate, polyethylene naphthalate, boribylene succinate, polylactic acid; styrene resins such as polystyrene, styrene-acrylonitrile resin, acrylonitrile-butadiene-styrene resin; ethylene-vinyl acetate resin, polyamide, polycarbonate, polychlorinated Thermoplastic resins such as vinyl, polyoxymethylene, polymethyl methacrylate, polymethacryl styrene, polyallyl sulfone can be used. These resins can be used not only as homopolymers but also as copolymers. The copolymer may be a binary system or a ternary or higher multi-element system, and may be a random copolymer or a block copolymer.

Among these, polyolefin resins and polyester resins are preferable from the viewpoint of processability and safety. Further, from the viewpoint of processability and safety, it is more preferable to use a polypropylene resin as the polyolefin resin, and it is more preferable to use polyethylene terephthalate or a copolymer thereof as the polyester resin.
These resins may be subjected to a treatment for enhancing crystallinity from the viewpoint of improving heat resistance, strength, light reflectivity, other physical properties and design properties, or known fillers, colorants and additives for these resins. A resin composition to which is added can also be used.

(Second resin material part)
The second resin material portion of the composite container of the present invention is formed by injection molding of a resin material, and constitutes a part of the resin material of the composite container. The second resin material part preferably has the shape of a container, and in particular, preferably has a structure that becomes an outer container of the composite container. The outer container here has at least a bottom part and a side wall part, and is a container that does not directly contact the contents put in the composite container. Usually, it is a container constituting the outside of the composite container. The second resin material portion can take various shapes such as a cylindrical shape with an open top, a cup shape, or a bottle shape, and has a similar shape to part or all of the first resin material portion. Also good.
For example, the second resin material portion may have a structure in which it is fused and integrated from the lower end portion of the fitting portion of the first resin material portion to the side wall portion (label portion) and the bottom portion. As shown in FIG. 2, the upper end portion of the second resin material portion forms a bent portion that is bent inward so as to be caught and locked to the lower end portion of the fitting portion of the first resin material portion. It is preferable to be integrated with the resin material part. There is no restriction | limiting in particular about the thickness of a 2nd resin material part, A thing which thickness changes continuously in a side wall part may be sufficient.

Examples of the resin material constituting the second resin material part include high-density polyethylene, medium-density polyethylene, polypropylene, poly (4-methylpent-1-ene), polyolefin elastomer, polyolefin ionomer, and ethylene Polyolefin resins such as vinyl acetate resin; Polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene succinate, polylactic acid, amorphous PET, polyester elastomer; polystyrene, styrene-acrylonitrile resin, acrylonitrile-butadiene -Styrene resins such as styrene resins, styrene-butadiene elastomers, styrene ionomers; polyamides, polycarbonates, polyvinyl chloride, polymers Examples include (meth) acrylic resins such as vinyl alcohol, polybutene, polyoxymethylene, polymethyl methacrylate, and polymethacryl styrene, and thermoplastic resins such as polyarylate, polyallyl sulfone, urethane elastomer, and urethane ionomer. . Furthermore, so-called green plastics such as bioplastics and biodegradable resins can be used.
These resins can be used not only as homopolymers but also as copolymers. The copolymer may be a binary system or a ternary or higher multi-element system, and may be a random copolymer or a block copolymer.

  The resin material used for the second resin material portion may be the same as or different from the resin material used for the first resin material portion. Further, the resin material used for the second resin material portion may be the same series as the resin material used for the first resin material section or may be a different series.

  The use of the same series of resins is preferable in that a strong fusion between the first resin material portion and the second resin material portion can be obtained, and recycling after use can be facilitated. For example, both the first resin material part and the second resin material part are preferably made of either a polyolefin resin composition or a polyester resin composition. Among these, in particular, for example, a polyolefin resin selected from the group consisting of a polypropylene resin composition for the first resin material part and a polyethylene resin, polypropylene resin, polyolefin elastomer resin and polyolefin ionomer resin for the second resin material part. It is preferable to use a base resin from the viewpoint of adhesion between the two. Furthermore, it is more preferable from the viewpoint of adhesiveness to use the same resin for both the first resin material portion and the second resin material portion. For example, both the first resin material part and the second resin material part are preferably made of a polypropylene resin composition or a polyethylene terephthalate resin composition from the viewpoint of the shrinkage rate of both. Even if the same resin is used for the first resin material portion and the second resin material portion, the first resin material portion and the second resin material portion can be made different by adding different dyes and pigments to the first resin material portion and the second resin material portion. The color of the material part and the second resin material part can be different.

  On the other hand, by making the resin material used for the first resin material part different from the resin material used for the second resin material part, a composite container combining the functions and characteristics of the respective resins can be realized. If such a combination is used, it becomes possible to improve the performance problem existing in the conventional container, and the design according to the use of the container becomes easy. Also, by making the resin material used for the first resin material part different from the resin material used for the second resin material part, a different texture is produced between the first resin material part and the second resin material part, and the label is attached. It can make it stand out or improve its design aesthetics. Such an embodiment is particularly useful in cosmetic containers and has high industrial applicability.

  As a case where the resin materials of the first resin material part and the second resin material part are different from each other, for example, the resin material of the first resin material part is made of a polyolefin resin composition or a polyoxyalkylene resin composition. Using a resin composition selected from the above, a polyester resin composition, a polystyrene resin composition, a polycarbonate resin composition, a (meth) acrylic resin composition, an ionomer resin composition as a resin material of the second resin material part, The case where the resin composition selected from the group which consists of an elastomer resin composition is used can be mentioned, Especially, from the polyolefin resin composition and the polyoxyalkylene resin composition to the resin material of the 1st resin material part. A resin composition selected from the group consisting of: a polyester resin composition and a polycarbonate resin composition as the resin material of the second resin material part , Mention may be made of the case of using the ionomer resin composition, a resin composition selected from the group consisting of elastomeric resin compositions.

  Some preferable specific examples in the case where the resin material used for the first resin material part and the resin material used for the second resin material part are different are illustrated. For example, for the first resin material part that becomes the inner container, polypropylene, polyoxymethylene, or the like that is excellent in content resistance (oil resistance, alcohol resistance, chemical resistance, etc.) is selected and used. 2 For the resin material part, select polyethylene terephthalate and ionomer with high transparency and excellent secondary decoration, polycarbonate with excellent light resistance and weather resistance, elastomer and ionomer with excellent fall resistance and scratch resistance, etc. Can be used. Further, when an inner container having a fitting portion (screw portion) with the lid is formed, the first resin material portion that becomes the inner container with the fitting portion has excellent slip properties (slack with the lid). (It does not occur) Polypropylene or the like can be selected and used, and the second resin material portion serving as the outer container can be selected and used without being slippery and easily adaptable to the hand. Furthermore, as a combination of highly transparent resins, a polyethylene resin terephthalate or the like that is hard and has high gas barrier properties is selected for the first resin material part that becomes the inner container, and the second resin material part that becomes the outer container has elasticity. It is also possible to select an ionomer that can be easily decorated. By adopting the combination exemplified here, in addition to the effect of adding the features of the two resins, the integration, stability, and visibility of the label when it is made an injection molded composite container will be even better. The effect is obtained.

  In addition, the label that mediates the first resin material part and the second resin material part is devised such as providing a heat seal layer on one side or providing a physical fitting effect by providing a through hole. By applying, adhesion between the two can be promoted.

  When it is desired to make it possible to visually recognize the label contained in the composite container from the outside of the composite container, it is necessary to use a transparent or translucent resin material for the second resin material portion serving as the outer container. However, if the decoration on the label only needs to be visible from the inside of the composite container, the second resin material portion that becomes the outer container does not necessarily need to be transparent or translucent, and an opaque resin material is used or sprayed. It is possible to make it opaque by painting or metal deposition. The second resin material portion may also be colored using an existing colorant. Moreover, what added a well-known filler, a coloring agent, and an additive may be used. Moreover, you may perform the process which improves crystallinity similarly to the 1st resin member.

  The outer surface of the second resin material portion may be glossy as a smooth mirror surface, may be matte as a rough surface such as satin, or may be provided with unevenness as emboss. A smooth surface is preferred. Moreover, you may process to raise crystallinity only to an outer surface.

If the surface is smooth, it is possible to give a further high-class feeling due to high gloss. Moreover, if the surface is smooth, it is easy to give decoration separately from the label on the outer surface of the second resin material part. Examples of the decoration here include adhesive labels, in-mold labels, stretch labels, shrink labels, direct printing, painting, metal foil transfer, metal deposition, roughening, embossing, and the like. If the surface is smooth, sticking adhesive labels or in-mold labels, attaching stretch labels or shrink labels, direct printing by silk printing, painting by spraying, metal foil transfer by hot stamping, decoration by metal vapor deposition, etc. (Secondary decoration) can be easily added.
If the surface is satin, the expression of blur can be intentionally added. Further, when embossing is applied, the unevenness acts as a lens, and a three-dimensional effect, a hologram effect, and the like can be added by combining with the decoration of the internal label.

  A label different from the label contained in the composite container may be fused to the outer surface of the second resin material portion. In such a case, decorations such as a landscape photograph and a window frame or a frame can be applied to the included label and the outer label can produce a sense of reality or a three-dimensional effect due to the overlap of the patterns. However, since the first resin material portion and the second resin material portion are integrally formed, for example, due to deformation of the outer container (second resin material portion) as described in JP-A-2006-143270. We cannot expect visual effects such as changes in moiré.

  In addition, the composite container of this invention may have a 3rd resin material part further. That is, the third resin material portion may be formed so as to straddle the surface of the first resin material portion, the surface of the second resin material portion, or both of these surfaces. At this time, the label fused to the surface of the second resin material portion may be enclosed and integrated by the third resin material portion. Further, another label may be fused to the surface of the third resin material portion.

Label (label visibility)
The label constituting the composite container of the present invention is completely enclosed between the first resin material portion and the second resin material portion and is integrally fused. Preferably, the label is integrally fused to the outer periphery of the first resin material part constituting the inner container and the inner periphery of the second resin material part constituting the outer container. The label is visible through a transparent or translucent resin material. In the present invention, it is preferable that the label can be visually recognized from the outside of the container via the transparent or translucent outer container (second resin material part), but via the transparent or translucent inner container (first resin material part). It may be visible from the inside of the container. Further, a combination of these may be used. The decorative surface of the label has the same interface as the inner peripheral surface of the outer container (second resin material portion) and the outer peripheral surface of the inner container (first resin material portion). Reflecting on the decoration, it is possible to enhance the sense of quality.
Moreover, since these labels are embedded between the first resin material part and the second resin material part, they do not come into direct contact with the contents of the container. For this reason, there is no concern in terms of safety and health such that the contents are contaminated by the printing ink or the like of the label.

(Base material of label)
The substrate is a label support that imparts strength, printability, and, in some cases, opacity to the label. Further, in the label molding, the heat seal layer is supported to facilitate molding, and can function advantageously from the viewpoint of raw material recycling.

  In the present invention, various materials and materials such as a resin film, an aluminum label, and pulp natural paper can be used as a label base material. Among them, it is preferable to use a resin film that can freely select between transparent and opaque as a label base material. Furthermore, it is particularly preferable to use, as the label base material, a resin film using a resin material of the same series as the container, which has good adhesion to the container and can be easily recycled.

  The resin film that can be used as the substrate contains a thermoplastic resin. Thermoplastic resins that can be film-formed are polypropylene resins, or polyethylene resins such as high-density polyethylene, medium-density polyethylene, and low-density polyethylene, and polyolefin-based resins such as polymethyl-1-pentene and ethylene-cyclic olefin copolymers. Resin, nylon-6, nylon-6,6, nylon-6,10, nylon-6,12 and other polyamide resins, polyethylene terephthalate and copolymers thereof, polybutylene terephthalate, polyethylene naphthalate, polylactic acid, aliphatic Examples thereof include polyester resins such as polyester, and thermoplastic resins such as polycarbonate, atactic polystyrene, syndiotactic polystyrene, and polyphenylene sulfide. These may be used in combination of two or more.

Among these, it is preferable to use polyolefin resin or polyester resin. It is more preferable to use a polypropylene resin as the polyolefin resin, and it is more preferable to use polyethylene terephthalate or a copolymer thereof as the polyester resin.
As the polypropylene resin, it is preferable to use an isotactic polymer or a syndiotactic polymer obtained by homopolymerizing propylene. Copolymers mainly composed of propylene having various stereoregularities obtained by copolymerizing propylene with α-olefins such as ethylene, 1-butene, 1-hexene, 1-heptene and 4-methyl-1-pentene. Polymers can also be used. The copolymer may be a binary system or a ternary or higher multi-element system, and may be a random copolymer or a block copolymer.

  Polyethylene terephthalate and its copolymers include copolymers composed of diols composed mainly of ethylene glycol and dicarboxylic acids composed mainly of terephthalic acid, or copolymers composed of hydroxycarboxylic acids copolymerizable with these raw materials. It is preferable to use a polymer. These may be a binary system or a ternary or higher multi-element system.

  The label used in the present invention may be transparent, translucent, or opaque. When using a resin film or the like as a base material and making them translucent and opaque, the resin film may contain an inorganic fine powder and / or an organic filler as a filler, or an inorganic fine powder and / or organic. The filler-containing resin film may be stretched to form a microporous stretched resin film having a large number of fine pores formed with the filler as the core, or a light-shielding layer may be provided by printing or coating to increase the light transmittance. You may adjust and you may combine these methods.

Here, “transparent” means that the opacity of the label used is 0 to 20%, “translucent” means that the opacity exceeds 20% and not more than 80%, and “opaque” means that the opacity is 80%. % Is 100% or less. What is opacity? JIS
Based on P-8149: 2000, the luminous reflectance measured by backing a standard black plate to a label test piece was divided by the intrinsic luminous reflectance measured by backing a standard white plate to the test piece. Values are expressed as percentages.

The kind of inorganic fine powder that can be used in the resin film is not particularly limited. Examples of the inorganic fine powder include heavy calcium carbonate, light calcium carbonate, calcined clay, talc, barium sulfate, diatomaceous earth, magnesium oxide, zinc oxide, titanium oxide, silicon oxide, silica, and alumina, and these are fatty acids. Etc., and may be surface-treated. Of these, heavy calcium carbonate, calcined clay, and talc are preferable because they are inexpensive and have good moldability.
The inorganic fine powder has an average particle size of generally 0.01 to 15 μm, preferably 0.02 to 8 μm, more preferably 0.03 to 4 μm, from the viewpoint of stable resin kneading, film stretching, and uniform pore formation. Things can be used.

The kind of organic filler that can be used in the resin film is not particularly limited. As the organic filler, it is preferable to select a different type of resin from the thermoplastic resin that is the main component of the resin film. For example, when the matrix resin is a polyolefin resin, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polystyrene, polycarbonate, polyamide, polyethylene sulfide, polyphenylene sulfide, polymethyl methacrylate, melamine resin, polyimide, polyethyl ether ketone, It is incompatible with polyolefin resins such as polyether ether ketone, poly (4-methyl-pent-1-ene), a cyclic olefin homopolymer and a copolymer of cyclic olefin and ethylene, and a melting point of 120 ° C. to Those having a glass transition temperature of 120 ° C. to 280 ° C. can be used.
As the organic filler, those having an average particle diameter after dispersion of usually 0.01 to 15 μm, preferably 0.02 to 8 μm, and more preferably 0.03 to 4 μm can be used as in the case of the inorganic fine powder.

  One of these inorganic fine powders and / or organic fillers may be selected and used alone, or two or more may be used in combination. When the resin film is desired to be translucent or opaque, the content of the inorganic fine powder and / or the organic filler in the resin film is preferably 0.5 to 65% by weight, and more preferably 3 to 50% by weight.

  The resin film may further contain a heat stabilizer, a light stabilizer, an antioxidant, a dispersant, a lubricant, a fluorescent whitening agent, a colorant, and the like, if necessary.

  The resin film constituting the substrate may be unstretched or stretched. It may be non-stretched from the viewpoint of curved surface followability at the time of injection molding, but at least uniaxially stretched from the viewpoints of weight reduction by pore formation, improvement of rigidity by molecular orientation, thinning and improvement of thickness uniformity, etc. It is preferred that Moreover, it is preferable that the said base material is comprised from several layers, and the surface and the back surface are comprised with the mutually different material. Thus, the label which consists of a heat seal layer mentioned later as a surface layer which is easy to give a decoration, for example, and a back surface layer is obtained by making a surface layer and a back surface layer into another base material. When the substrate is composed of a plurality of layers, it is preferable that at least one layer thereof is stretched. When extending | stretching a several layer, you may extend | stretch separately before laminating | stacking each layer, and you may extend | stretch after laminating | stacking. Further, the stretched layer may be stretched again after being laminated. Furthermore, you may extend | stretch the whole, after forming a heat seal layer in a base material.

  Various conventionally known methods can be used for stretching the resin film constituting the substrate. For example, after a molten resin is extruded and formed into a sheet using a T die or I die connected to a screw type extruder, the sheet is stretched longitudinally using a difference in peripheral speed of a group of rolls. , Transverse stretching method using a tenter oven, simultaneous biaxial stretching method using a combination of a tenter oven and a linear motor, simultaneous biaxial stretching method using a tenter oven and a pantograph type stretching device, the sheet A biaxial stretching method that stretches using a pantograph-type stretching device after cutting, and a molten resin is extruded into a tube shape using a circular die connected to a screw-type extruder, and then blown and stretched with air And simultaneous biaxial stretching (inflation molding) method.

  When the thermoplastic resin is an amorphous resin, the stretching temperature should be set to be equal to or higher than the glass transition point of the resin to be used. Can do. Specifically, the temperature is 2 to 60 ° C. lower than the melting point of the thermoplastic resin to be used. For example, when the resin is a propylene homopolymer (melting point 155 to 167 ° C.), 152 to 164 ° C., high density polyethylene (melting point 121 to 134 ° C.) is preferably 110 to 120 ° C. The stretching speed is preferably 20 to 350 m / min. If the stretching speed is within the same range, the productivity of the resin film is stable, which is preferable.

(Coat layer)
The label used in the present invention is characterized in that a coating layer capable of digital printing and fusion with the resin material portion is provided on at least one surface thereof. Therefore, the label used in the present invention may have a coating layer on both sides.
The coating layer in the present invention fixes a color material used in the printing method when digital printing is performed on the label by at least one method selected from the group consisting of a dry electrophotographic method, a wet electrophotographic method, and an inkjet method. However, when the composite container is injection molded at the same time, the coat layer also has good fusion with the molten resin material part, which promotes the integration of the label and the resin material part. , Has the function of improving mutual adhesion. In the present application, “immobilization” means that when the label and the resin material portion are fused and integrated, the color material is held in the coating layer to such an extent that the color material is not washed away by the molten resin material portion. Means that.
According to the present invention, since the color material for printing is firmly fixed to the coat layer, the color material for printing is washed away even when the printing surface comes into contact with the melted resin material portion when molding the composite container. There is no. Therefore, since it is not necessary to further laminate a heat seal layer, a laminate film, or the like on the printing surface, there is an advantage that a composite container can be created with fewer steps.
That is, the coating layer in the present invention has two characteristics such as improvement of suitability for a digital printing system as a printing surface and promotion of fusion integration with a resin material portion as an adhesion surface.

In JP 2009-263006 A, a general-purpose oil-based offset ink, UV offset ink, and gravure ink are used to print a label by a technique such as offset printing, gravure printing, and letter press printing. The ink has a tendency to inhibit fusion with the resin material portion, and consequently to prevent integration of the label and the resin material portion. In addition, these printing inks may be easily washed away by contact with the molten resin material part. Therefore, in most labels, a heat seal layer is further provided on the printing surface, a laminate film is provided on the printing surface, the printing surface is protected by perforation, and the label and the resin material part are integrated. We are forced to take measures such as promoting
The label used in the present invention enables digital printing by providing a coat layer, and also has good fusion with the molten resin material part, so that the above lamination and perforation are particularly necessary. do not do. In addition, in digital printing, the dry electrophotographic system, wet electrophotographic system, and melt ink jet system (solid ink jet system) are characterized by the fact that the color material used is melted by heat. It is expected to promote the fusion and integration of the resin material part with the resin material part, which is particularly preferable.

The coating layer in the present invention is selected from the group consisting of polyethylene imine resin, polyamide polyamine resin, polyvinyl alcohol resin, polyether urethane resin, styrene-butadiene copolymer resin, vinyl chloride-vinyl acetate copolymer resin in accordance with the printing method used. It is preferable that at least one of these is included as a binder resin. The content of these resins is preferably 5 to 100% by weight, more preferably 10 to 60% by weight based on the total solid content of the coat layer, and 20 to 50% by weight. Is more preferable.
Especially in the case of dry electrophotographic method, polyvinyl alcohol resin or vinyl chloride-vinyl acetate copolymer resin, in the case of wet electrophotographic method, polyethyleneimine resin, polyamide polyamine resin, styrene-butadiene copolymer resin, in the case of inkjet method. It is preferable to use a coating layer containing a polyvinyl alcohol resin, a styrene-butadiene copolymer resin, or a polyether urethane resin as a binder resin, from the viewpoint of affinity with the colorant.

  The coat layer may be a pigment coat obtained by adding a conventionally known pigment such as silica, calcium carbonate, clay, titanium oxide, barium sulfate to the binder resin. Addition of a pigment is preferable because the adsorption of the coloring material is promoted, and the biting of the coloring material and the melted resin material portion due to the formation of surface irregularities is improved. The added amount of the pigment is preferably 0 to 95% by weight, more preferably 40 to 90% by weight, and further preferably 50 to 80% by weight based on the total solid content of the coat layer. preferable. Examples of the pigment that can be used in the present invention include silica, clay, and barium sulfate.

The label used in the present invention may be a printable layer provided with a coat layer on one side thereof, or may be provided with a coat layer on both sides thereof.
If the label used in the present invention may be printed on one side thereof, the coating layer may be provided on one side accordingly. In this case, it is preferable in terms of molding the composite container of the present invention that the label has the following heat seal layer on the other surface.

(Heat seal layer)
The label used in the present invention is preferably in a form in which a layer of a heat sealant (generally a heat seal resin) is provided on the outermost layer on the side that does not require printing.
In the present invention, the heat seal layer promotes adhesion between the label and the container and is solid at room temperature, but when the first resin material portion or the second resin material portion is molded in the mold. It is activated by the heat of the molten resin, and is fused with the molten resin. After cooling, the resin becomes solid again and can exhibit a strong adhesive force.

  In the label used in the present invention, the heat seal layer is laminated on the substrate and provided as a part of the label. More specifically, it can be provided by coating on one side of the base material, by melt lamination on the base material, or by co-extrusion with the base material in the production process if the base material is a resin film. .

As an example of manufacturing a specific label including the formation of a heat seal layer, first, a heat sealant is applied to one side of a substrate such as a film by a technique such as coating or extrusion lamination, or heat sealing is integrally performed on this when forming a film. A method of providing a heat seal layer by laminating and coextruding the layers can be mentioned. Further, after decorating a substrate such as a film by offset printing or the like, a heat seal agent can be applied by a technique such as coating or extrusion lamination to provide a heat seal layer. Therefore, the label of the present invention may have a form having a coating layer + digital printing on one side and double-sided printing by offset printing etc. + heat sealing layer on the other side.
Among those skilled in the art, digital printing in which variable information can be inserted for each part may be referred to as “variable printing”, and conventional printing techniques that are not capable of inserting variable information but are suitable for mass printing may be referred to as “static printing”. Each has advantages and disadvantages. Although the label combining these printing techniques has the disadvantage of increasing the number of processes, by combining these advantages, for example, a composite container having both tailor-made and fine beauty can be provided.

  The type of the thermoplastic resin material used for the heat seal layer is not particularly limited as long as it has a function of bonding a label to a resin material part by heating when forming a container by injection molding.

  The thermoplastic resin constituting the heat seal layer in the present invention preferably has a melting point of 60 to 130 ° C. determined as a peak temperature by DSC measurement. If it is lower than 60 ° C., the stickiness of the label deteriorates due to stickiness at room temperature, and blocking or the like is likely to occur. Therefore, when inserting the label into the mold, troubles such as inserting two sheets are likely to occur frequently. On the other hand, if the temperature exceeds 130 ° C., the adhesion between the label and the molded body tends to deteriorate, such being undesirable.

  Examples of specific thermoplastic resins include polyolefin resins, low density to medium density high pressure polyethylene, linear linear polyethylene, ethylene, α-olefin copolymer, propylene / α-olefin photopolymer, Ethylene / vinyl acetate copolymer, ethylene / acrylic acid copolymer, ethylene / alkyl acrylate ester copolymer, ethylene / methacrylic acid alkyl ester copolymer (alkyl group having 1 to 8 carbon atoms), ethylene / methacrylic acid Examples thereof include polyethylene resins having a melting point of 60 to 130 ° C. such as metal salts of acid copolymers (Zn, Al, Li, K, Na, etc.). These resins may be used alone or in combination of two or more.

  Other known additives for resin can be arbitrarily added to the heat seal layer as long as the performance required for the heat seal layer is not impaired. Examples of such additives include dyes, nucleating agents, plasticizers, mold release agents, antioxidants, antiblocking agents, flame retardants, ultraviolet absorbers, and dispersants.

  The heat seal layer has a three-dimensional center based on JIS-B-0601: 2001 in order to prevent the generation of blisters due to air entrainment between the label and the first resin material part during in-mold molding. The surface average roughness (SRa) preferably has a concavo-convex shape of 1 to 10 μm, and more preferably has a concavo-convex shape of 2 to 8 μm. In order to give such an uneven shape, the heat seal layer can be embossed if necessary. The embossing can be carried out at the time of molding the heat seal layer or by pressing the embossing roll after molding to transfer the roll pattern. If the irregular shape is smaller than 1 μm, air is trapped between the molded body and the label at the time of injection molding, and an appearance defect called blister is likely to occur, which is not preferable. If it is 10 μm or more, the uneven pattern appears on the appearance on the label decorative surface side, and printing unevenness is likely to occur during printing, and transfer unevenness is likely to occur during transfer of the metal foil, which is not preferable. Examples of such an embossed shape include a regular uneven shape in which convex portions (head-cut pyramid shape) and hemispherical convex portions formed by cutting off the apex of a regular square pyramid are arranged at equal intervals, or a satin finish.

(Decoration)
The label used in the present invention can be decorated such as printing including digital printing and metal foil transfer. In this case, at least one surface of the label is a decorative surface, or both surfaces are decorative surfaces. In the present invention, the decoration on the label is preferably bonded to the container to be integrated and can be visually recognized through the container.

The label used in the present invention includes, as decoration, a product name, brand name, manufacturer, sales company name, usage method, precautions for use, contact information, barcode, two-dimensional barcode, etc., corporate mark, service Designs such as marks, logos, characters, designs and patterns can be provided by printing.
As a printing method, at least digital printing is performed. However, as long as the adhesion to the container is not disturbed, in addition to digital printing, various types of printing such as conventional sheet-fed offset printing, rotary offset printing, gravure printing, flexographic printing, letter press printing, convex ring printing, screen printing, etc. It is also possible to adopt a method.

(Digital printing)
The label used in the present invention is preferably subjected to electrophotographic or inkjet digital printing. As the electrophotographic system, a dry electrophotographic system, a wet electrophotographic system, or the like can be adopted. As the ink jet method, a water-based ink jet method, a solvent ink jet method, a UV ink jet method, a melt ink jet method, a latex ink jet method, or the like can be adopted. According to the electrophotographic method, higher-speed printing is possible, and according to the ink-jet method, finer printing is possible.
Among these, the wet electrophotographic method is particularly preferable because it combines high speed and fineness. Specific examples of the wet electrophotographic printing machine include the Indigo series manufactured by Hewlett-Packard Co., and models such as 7000, 5500, 3500, W7200, W3250, WS6000, WS4500, and WS4000.

  The label used in the present invention is developed with metal foil transfer such as hot stamp and cold stamp, metal direct vapor deposition, metal transfer vapor deposition, and photosensitive resin exposed to interference fringes to further improve the design (hologram formation). ) And the like. These decorations may be used in combination.

(Perforation)
The label used in the present invention can have a through hole formed by perforation. By having the through-hole, when the first resin material portion and the second resin material portion are fused, the molten resin flows into the through-hole, and the effect of improving the adhesion by physical fitting is obtained. , It becomes easier to integrate, which is a preferred mode.

  As a method of forming a perforated structure through the label, a roller with diamond particles, a hot needle, a mechanical perforation method using a punching blade, a laser beam irradiation perforation method, an electron beam irradiation perforation method, a plasma perforation method, a high-pressure discharge At least one perforation method selected from perforation methods can be applied, and can be appropriately selected according to the label material, thickness, passage speed, and perforation diameter.

  In the perforations formed on the label, the pitch between adjacent perforations is preferably distributed in the range of 3 to 30 mm, more preferably in the range of 4 to 20 mm, and particularly preferably in the range of 5 to 15 mm. ing. When the pitch is less than 3 mm, the perforations become conspicuous in the decorative appearance, which is not preferable. When it exceeds 30 mm, the effect of improving the adhesiveness by fitting cannot be obtained to a desired extent. Further, it is preferable that the perforations are uniformly distributed on the label from the viewpoint of obtaining uniform adhesiveness.

  The perforations formed on the label preferably have a hole diameter of 0.05 to 2 mm, more preferably 0.1 to 1 mm, and particularly preferably 0.2 to 0.8 mm. Here, the hole diameter refers to the diameter when the cross-sectional shape of the hole is a circle, and the long diameter (maximum diameter) otherwise. When the perforation diameter is less than 0.05 mm, the molten resin does not flow into the perforations, and the initial purpose cannot be achieved. When the diameter of the perforations exceeds 2 mm, the perforations become conspicuous in the decorative appearance, which is not preferable.

When the label used in the present invention uses a resin film for the base material, the peripheral edge of the perforation undergoes thermal deformation or plastic deformation in accordance with the perforation treatment, so that the resin rises in the thickness direction of the film after penetration, and the film The protrusion part (raised part, burr | flash) in which thickness increased from original thickness may be formed.
When the protrusion is integrated with the label by injection molding of the first resin material part or the second resin material part, it forms a structure that fits at the container / label interface as a ridge protruding to the container side, and further has an adhesive force. Contributes to improvement.

(Label shape)
The label used in the present invention is formed by punching the above-described label base material into a size and shape used for a composite container after passing through a process such as decoration, and is used for forming a composite container.

  The label used in the present invention may be integrated with the outer peripheral wall with respect to the shape of the first resin material portion, may be integrated with the bottom portion, or may be a combination thereof. By interposing a label not only on the outer peripheral wall but also on the bottom, even when different resin compositions are used for the first resin material part and the second resin material part, these labels mediate most of the joint surfaces. The adhesive strength between the two can be improved to facilitate integration, and the light shielding and gas barrier properties can be improved by designing the label.

  The shape of these labels may be rectangular, trapezoidal, fan-shaped on the side wall, circular, donut-shaped, or polygonal, including a square on the bottom, according to the shape of the first resin material. it can. For example, as shown in FIG. 1 of Japanese Utility Model Laid-Open No. 01-055970 and FIG. 1 and FIG. 2 of Japanese Laid-Open Patent Application No. 07-232723, labels used for the side wall and bottom are shown. An integral shape may be used. According to the configuration of the composite container of the present invention, the contents and the label are not in direct contact with each other, so that no matter what shape is selected as the label shape, ink leakage does not occur from the end of the label.

Relationship between resin material and label (combination)
When both the first resin material part serving as the inner container and the second resin material part serving as the outer container are transparent or semi-transparent, and the label is transparent or semi-transparent, the contents and content can be passed through the composite container. Can be confirmed.
If the outer and inner containers are transparent or translucent and the label is opaque, the label can be seen from the inside and outside of the composite container, so the inner container is opaque, for example, with different decorations on the front and back of the label, and When the outer container and the label are transparent or semi-transparent, the label information is further added to the container having a deep hue similar to the utility model registration No. 3114093 by visually recognizing the formation of the inner container from the outer appearance of the container. Can be provided.
When the outer container is transparent or translucent and the inner container and the label are opaque, the information and decoration on the label can be seen more clearly than the conventional composite container. In the composite container of the present invention, the inner container, the outer container, and the label are integrated, and since there is no air layer between the inner container or the outer container and the label, light reflection and diffraction at the interface can be suppressed. is there. As a result, decoration such as printing applied on the surface of the label is clearly visible without blurring due to light diffusion.

  The thicknesses of the outer container and the inner container sandwiching the label can be appropriately determined according to the use, regardless of whether the both are transparent, translucent or opaque. For example, when a transparent or translucent colored resin is used as the material of the composite container, a three-dimensional gradation can be expressed in the composite container of the present invention by changing the thicknesses of the side walls of the inner container and the outer container. .

(Integrated with fusion)
In the manufacturing method of the present invention, the label is included between the first resin material portion and the second resin material portion, and both surfaces of the label are fused and integrated with each resin material. And In the present invention, “fusion” means that the members constituting the two surfaces to be joined to each other are melted and diffused by heat, and the two surfaces are joined by cooling with the two surfaces in contact with each other. Means that. In the present invention, “integrated” means that the respective contact surfaces of the plurality of members are tightly joined in a state where there is no floating or air accumulation.

Manufacturing method of composite container (Description of manufacturing method)
The manufacturing method of the composite container of this invention will not be restrict | limited especially if the composite container described in a claim can be provided. A preferable manufacturing method is a method in which digital printing is performed on the coat layer of the label, the first resin material portion with a label is formed by injection molding, and then the second resin material portion is formed by injection molding so as to enclose the label. is there. A particularly preferred production method is the production method of the present invention comprising the following three steps.
(1) A step of performing digital printing on the coat layer of the label having a coat layer on at least one surface;
(2) The label is formed by injecting and molding the first resin material into the first mold after the label is placed and fixed on the inner wall of the first mold on the female mold side and the mold is closed. Forming a fused first resin material part; and
(3) The mold is closed between the first resin material part as a male mold or a part of the male mold and the second mold as a female mold so as to completely enclose the label on the first resin material part. The step of forming the second resin material part so as to cover the label on the first resin material part by injecting and molding the second resin material

  In step (1), digital printing is performed on the coat layer of the label. For the details of the coating layer and the details of the digital printing, the above description can be referred to. When the coating layer is provided on both sides, digital printing may be performed on both sides, or digital printing may be performed only on one side. In the present invention, by changing the printing contents and digitally printing a plurality of labels, labels with different printing contents can be obtained easily and quickly. The print content can be changed by controlling an electrical signal that designates the print content. In conventional methods such as offset printing, in order to change the contents of printing, it is necessary to prepare plate making and printing plates (lithographic plates, letterpress plates, stencil plates, etc.) each time. However, according to the present invention, printing is simple. The contents can be changed.

  In the step (2), a label is arranged and fixed on the inner wall on the female mold side of the first mold. The 1st metal mold | die here has a cavity structure corresponding to the shape of the 1st resin material part to form. The label is disposed and fixed at a location corresponding to a position where the label is scheduled to be fused to the first resin material portion. At that time, the label is fixed to the inner wall of the mold using a known method such as suction or static electricity. More specifically, the first mold is composed of a female mold and a male mold. That is, the label is fixed to the inner wall of the female mold, and the mold is closed with the male mold.

  Next, the first resin material is injected and molded into a first mold having a label fixed to the inner wall on the female mold side. The injection and molding referred to here can be performed by appropriately selecting methods used in ordinary injection molding techniques and combining them as necessary. By performing this step (2), it is possible to obtain a first resin material portion having a desired shape in which a label is fused at a desired position. The first resin material part is preferably molded so as to have the shape of a container, and more preferably, the first resin material part is molded so as to constitute the main container of the composite container to be manufactured. As described above, the label can be fused at various positions depending on the purpose and application. For example, the label can be fused to the side wall portion and / or the bottom portion of the first resin material portion having a container shape. At this time, a plurality of labels may be fused simultaneously, or only one label may be fused.

  It is preferable that the inner wall of the female mold for fixing the label at the time of injection molding is curved or bent from the viewpoint that the effects of the present invention can be better enjoyed, and more preferably curved. In other words, the inner wall of the female mold for fixing the label preferably includes a curved surface or a valley line, and more preferably includes a curved surface. When a curved surface is included, the inner wall of the female mold for fixing the label may be curved with a constant curvature throughout, or the curvature may be continuously changed. Further, a part of the inner wall of the female mold may be curved, and the other part may be planar. When the inner wall of the female mold for fixing the label includes a valley line, a plane may be connected to the valley line, or a curved surface may be connected. There may be a plurality of valley lines.

  By injection molding using such a first mold, for example, a first resin material portion comprising a side wall portion and a bottom portion having a circular or oval cross section, and a label is fused to the side wall portion from the outside. A thing (a thing which fuse | fused the label to the outer peripheral wall) can be obtained. Further, the side wall portion can be made of a portion having a curvature and a portion not having a curvature, and a label can be obtained by fusing a label to the portion having a curvature from the outside. Further, the cross section composed of a plurality of mountain lines and the same number of planar side plates is a first resin material part having a polygonal side wall part and a bottom part, and the label is fused so as to straddle at least one mountain line. You can also get things. In these specific examples, it is also possible to form a label on a portion having no curvature or a portion not including a valley line. Moreover, the aspect in which the label is formed in the shape of a headband around the side wall can also be mentioned as a preferred example.

  As a device for forming the first resin material portion, a conventionally known device that combines an injection device and a mold clamping device, and in some cases a label inserter, a container take-out robot, or the like can be used. The insertion of the label into the mold and the removal of the molded first resin material part from the mold may be performed continuously by a robot or manually by each shot. When forming the first resin material portion, the label is mounted and fixed at a desired position on the inner wall of the mold, but if it is not desired to process the suction hole for suction fixation on the mold, the label is attached with a charging device. Either by charging and adsorbing it on the inner wall of the mold, or by forming the first resin material part into an edge shape with the shoulder and the bottom of the container being raised as shown in FIG. Then, the label can be fixed to the inner wall of the mold. It is preferable to apply such a shape to the mold because it becomes unnecessary and economical to apply the suction hole processing that has been conventionally performed with an in-mold film to the mold. Further, in FIG. 1, the shoulder portion of the first resin material portion may be completely cornered.

  Before forming the first resin material portion and proceeding to the formation of the second resin material portion in step (3), the first resin material portion is further directly printed by screen printing, foil stamping by hot stamping, ink jet, laser, etc. Decoration by printing (engraved) or sticking an adhesive label may be applied.

  In step (3), the second resin material portion is formed by injection molding on the surface of the labeled first resin material portion obtained in step (2) so that the label is completely covered. Here, the mold is closed with the second mold. At this time, the mold is closed so that the label is completely contained in the mold. The cavity shape of the second mold is determined according to the shape of the second resin material part to be formed. When the first resin material portion has the shape of a container, it is preferable that the second mold has a shape that can be closed outside the first resin material portion. At this time, the first resin material part is mounted inside the second mold and serves as a mold (male mold) or a part of the mold (male mold) that forms the inside of the second resin material part. . Thereafter, the mold is closed with a second mold as a female mold having a cavity structure, and a second resin material is injected to form a composite container.

By performing this step (3), a composite container in which the second resin material portion having a desired shape is formed at a desired position can be obtained. Furthermore, it is preferable that the second resin material part is also molded so as to have the shape of a container, whereby the first resin material part and the second resin material part are integrated to form a composite container containing a label.
When the step (3) is performed, a new label can be fixed to the inner wall of the second mold (female mold) to perform injection molding. Thus, a composite container having a second label fused to the outer surface of the second resin material part in addition to the label enclosed between the first resin material part and the second resin material part is manufactured. be able to.

  As a device for forming the second resin material portion, similarly to the case of the first resin material portion, a known injection device and a mold clamping device, and in some cases a device that combines a container insertion and removal robot, a label inserter, and the like are used. be able to. The insertion of the first resin material portion into the apparatus and the removal of the composite container may be performed manually every shot.

  The outer surface of the second resin material portion may be glossed as a smooth mirror surface by processing the inner wall of the second mold (female mold) to be used, or matte as a rough surface such as satin. You may give an unevenness | corrugation as embossing. A smooth surface is preferred. Moreover, the decoration provided separately outside the second resin material portion may be performed simultaneously with the formation of the second resin material portion or after the formation of the second resin material portion.

  In this way, an injection-molded composite container in which the label is enclosed between the first resin material part and the second resin material part, and both surfaces of the label are fused and integrated with each resin material. Can be manufactured. For example, a container having a side wall and a bottom, in which a label is contained in a headband shape in the side wall, or one or more labels that are curved or bent are contained in the side wall. Can be manufactured.

It is also possible to further form the third resin material part by performing a process according to the process (3) on the obtained composite container. At this time, the third resin material portion may be formed on the surface of the first resin material portion, may be formed on the surface of the second resin material portion, or the first resin material portion and the second resin material. You may form so that it may straddle each surface of a part. Further, when the second label is fused in the step (3), the third resin material portion may be formed so as to enclose the second label. Furthermore, a third label can be fused to the surface of the third resin material portion.
Similarly, the fourth resin material portion can be formed, or the label can be fused to the surface thereof. These applications and modifications can be easily performed by those skilled in the art.

  Hereinafter, the present invention will be described more specifically with reference to examples. The injection molding of the present invention, wherein the label is encapsulated in the resin material by the method described below or a method according thereto, and both sides of the label are fused and integrated with the resin material Composite containers can be manufactured. That is, the materials, amounts used, ratios, and production procedures shown in the following production examples and examples can be appropriately changed without departing from the gist of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below.

The production example of the label base material that can be used in the present invention is shown below (Production Example 1 of the label base material).
Propylene homopolymer (trade name “NOVATEC PP MA8Q”, manufactured by Nippon Polypro Co., Ltd.) 81% by weight, high density polyethylene (trade name “NOVATEC HDHJ360”, manufactured by Nippon Polyethylene Co., Ltd.) 3% by weight, and average particle diameter Is melt-kneaded with an extruder set at a temperature of 250 ° C., and then extruded into a sheet form from a die, and further cooled by a cooling device. Cooled to obtain an unstretched sheet. Next, the sheet was heated again to a temperature of 150 ° C., and then stretched 5 times in the longitudinal direction using a group of rolls having different peripheral speeds to obtain a 5 times longitudinally stretched film (core layer).
Furthermore, as a surface layer, a resin composition (mixture of 54% by weight of a propylene homopolymer (trade name “NOVATEC PP MA3AQ”, manufactured by Nippon Polypro Co., Ltd.) and 46% by weight of calcium carbonate having an average particle diameter of 1.25 μm ( B) was melt-kneaded at 250 ° C. in another extruder, and then extruded into a sheet form from a die, and laminated on both sides of the 5-fold longitudinally stretched film obtained in the above process to form a laminated film having a three-layer structure. Obtained. Next, the laminated film having the three-layer structure was cooled to a temperature of 60 ° C., then reheated to a temperature of 155 ° C. by an oven, and stretched 7.5 times in the transverse direction using a tenter (area stretch ratio: 37.5 times), annealing treatment at a temperature of 165 ° C., cooling to a temperature of 60 ° C., slitting the ear portion, and a thickness of 80 μm of a three-layer structure (uniaxial stretching / biaxial stretching / uniaxial stretching) (B / A / B = 17 μm / 46 μm / 17 μm), and an opaque polyolefin-based film used for the label of the present invention having an opacity of 91% was obtained.

(Label substrate production example 2)
Propylene homopolymer (trade name “Novatech PP MA8Q”, manufactured by Nippon Polypro Co., Ltd.) 81% by weight, high density polyethylene (trade name “Novatech HD HJ360”, manufactured by Nippon Polyethylene Co., Ltd.) 3% by weight, and average particle A resin composition (A) composed of 16% by weight of calcium carbonate powder having a diameter of 1.25 μm was melt-kneaded at 250 ° C. using an extruder, and then extruded into a sheet form from a die and further cooled by a cooling device. An unstretched sheet was obtained. Next, the sheet was heated again to about 150 ° C. and then stretched 4 times in the longitudinal direction using the peripheral speed of the roll group to obtain a 4 times longitudinally stretched film (core layer).
On the other hand, propylene homopolymer (trade name “Novatech PP MA3AQ”, manufactured by Nippon Polypro Co., Ltd.) 51.5% by weight, high density polyethylene (trade name “Novatech HD HJ580N”, manufactured by Nippon Polyethylene Co., Ltd.) 3.5 A resin composition (B) comprising 42% by weight of calcium carbonate powder having an average particle size of 1.25 μm and 3% by weight of titanium oxide powder having an average particle size of 0.8 μm was melted at 240 ° C. using another extruder. This was kneaded, extruded onto the surface of the uniaxially stretched film in a sheet form from a die, and laminated to obtain a surface layer / core layer (B / A) laminate.

  Further, as a back layer, a propylene homopolymer (trade name “Novatech PP MA3AQ”, manufactured by Nippon Polypro Co., Ltd.) 51.5% by weight, high density polyethylene (trade name “Novatech HD HJ580N”, manufactured by Nippon Polyethylene Co., Ltd.) A resin composition (C) comprising 3.5% by weight, 42% by weight of calcium carbonate powder having an average particle diameter of 1.25 μm and 3% by weight of titanium oxide powder having an average particle diameter of 0.8 μm, and a metallocene catalyst as a heat seal layer An ethylene / 1-hexene copolymer having a MFR of 18 g / 10 min and a density of 0.898 g / cm 3 obtained by copolymerizing ethylene and 1-hexene (1-hexene content 22% by weight, crystallinity) 30, number average molecular weight 23,000) 75% by weight, MFR 4 g / 10 min, density 0.92 g / cm 3, crystallinity (X-ray method) 40%, A resin composition (D) made of a mixture of 25% by weight of a high-pressure low-density polyethylene having a number average molecular weight of 18,000 is melt-kneaded at 230 ° C. using separate extruders, and a single co-extrusion die is used. Supply and laminate in the die (C / D), extrude into a sheet form from the die, and laminate so that the heat seal layer is the outermost layer on the core layer side (A side) of the laminate (B / A) Thus, a laminate (B / A / C / D) having a four-layer structure of surface layer / core layer / back surface layer / heat seal layer was obtained. The heat-seal layer side of the obtained laminate was passed through an embossing roll (150 lines per inch, depth 40 μm, reverse gravure type) made of a metal roll and a rubber roll, and 0.17 mm intervals on the heat-seal layer (D) side. The pattern was embossed.

  This four-layered laminate is guided to a tenter oven, heated to 155 ° C., stretched 7 times in the transverse direction using a tenter, then heat-set at 164 ° C., further cooled to 55 ° C. A slit is used to stretch a thermoplastic resin stretched film having a thickness of 80 μm (B / A / C / D = 24 μm / 32 μm / 21 μm / 3 μm) having a four-layer structure (uniaxial stretching / biaxial stretching / uniaxial stretching / uniaxial stretching). An opaque polyolefin film used for the label of the present invention having a transparency of 87% was obtained.

Examples of producing labels used in the composite container of the present invention are shown below.
(Label production example 1)
The opaque polyolefin film obtained in Production Example 1 for the label base material was slit to form a 250 mm wide roll. Using a gravure coater on both sides of the film, a coating solution containing a polyamide polyamine resin (trade name “Topaz 17 solution”, manufactured by Toyo Ink Co., Ltd.) is about 0.5 g / m 2 in solid content per side. And dried to form a coat layer.
A wet electrophotographic printer (Indigo WS4000 manufactured by Hewlett Packard) was used for printing logos and geometric patterns with 7 colors on one side, and a gradient with a single color on the other side. After printing, it was punched into a fan shape in accordance with the container shape to obtain a label used for the composite container of the present invention.

(Label production example 2)
It is used for the composite container of the present invention in the same manner as in Label Production Example 1 except that polyethyleneimine resin (trade name “ADCOAT 372MW”, manufactured by Toyo Morton Co., Ltd.) is used as the coating liquid for forming the coating layer. Got a label.

(Label production example 3)
The composite container of the present invention was used in the same manner as in Label Production Example 1 except that polyethyleneimine resin (trade name “Epomin P-1000”, manufactured by Nippon Shokubai Co., Ltd.) was used as the coating liquid for forming the coating layer. The label used for was obtained.

(Label production example 4)
The coating liquid for forming the coating layer was the same as that of Label Production Example 1 except that an alkyl-modified polyethyleneimine resin (trade name “Saftmer AC-72”, manufactured by Mitsubishi Chemical Corporation) was used. The label used for the composite container was obtained.

(Label production example 5)
The opaque polyolefin-based film obtained in Production Example 2 for the label substrate was slit into a small roll having a width of 250 mm. A coating liquid having the following composition was coated on the surface of the B layer side of the film using a gravure coater so that the solid content was about 2.0 g / m 2 and dried to form a coating layer.
A logo and a geometric pattern were printed in seven colors on the coated surface using a wet electrophotographic printer (trade name “Indigo WS4000”, manufactured by Hewlett-Packard Company). After printing, it was punched into a fan shape in accordance with the container shape to obtain a label used for the composite container of the present invention.
<Coating solution composition>
Synthetic silica powder 100 parts by weight (trade name “Mizukasil P-78D”, average particle size 8 μm, manufactured by Mizusawa Chemical Co., Ltd.)
30 parts by weight of polyvinyl alcohol (trade name “Kuraray Poval PVA-117”, manufactured by Kuraray Co., Ltd.)
10 parts by weight of an epichlorohydrin adduct of polyamide polyamine (trade name “WS4082”, manufactured by Seiko PMC Co., Ltd.)
Polyacrylic acid soda 5 parts by weight (reagent, manufactured by Wako Pure Chemical Industries, Ltd.)
1600 parts by weight of water

(Label production example 6)
The opaque polyolefin film obtained in Production Example 1 for the label base material was slit to form a 250 mm wide roll. A coating liquid having the following composition was applied to one side of the film using a gravure coater so that the solid content was about 2.0 g / m 2 and dried to form a coating layer.
Next, a hologram pattern of a metal foil (trade name “Algrass”, manufactured by Toppan Prosprint Co., Ltd.) is transferred to the other surface, and an ethylene-vinyl acetate copolymer resin-based heat sealant (trade name) “Adcoat AD1790-15” (manufactured by Toyo Morton Co., Ltd.) was coated with a Mayer bar so that the solid content was 2 g / m 2 and dried to provide a heat seal layer on the same surface.
A logo and a geometric pattern were printed in seven colors on the coated surface using a wet electrophotographic printer (trade name “Indigo WS4000”, manufactured by Hewlett-Packard Company). After printing, it was punched into a fan shape in accordance with the container shape to obtain a label used for the composite container of the present invention.
<Coating solution composition>
Styrene-butadiene latex 33 parts by weight (trade name “0696”, solid content concentration: 48%, manufactured by JSR Corporation)
11 parts by weight of acrylic ester-based resin latex (trade name “Nippol LX811H”, solid content concentration: 50%, manufactured by Nippon Zeon Co., Ltd.)
Clay 70 parts by weight (Brand name "Ansilex 93", manufactured by BASF)
25 parts by weight of calcium carbonate (trade name “Softon 1800”, average particle size: 1.25 μm, manufactured by Bihoku Flour Industry Co., Ltd.)
5 parts by weight of titanium oxide (trade name “Taipeke CR-60”, manufactured by Ishihara Sangyo Co., Ltd.)
12 parts by weight of antistatic agent (trade name “Saftmer ST1100B”, solid content concentration: 4%, manufactured by Mitsubishi Chemical Corporation)

(Label production example 7)
The opaque polyolefin film obtained in Production Example 1 for the label base material was slit to form a 250 mm wide roll. A geometric pattern was printed on one side of the film using a rotary offset printer and 4 color UV offset process ink. A polyolefin hot melt adhesive (trade name “F Coat”, manufactured by Nippon Kakko Co., Ltd.) is applied to the surface side of the printed surface that has been subjected to a geometric pattern after printing. Formed.
Next, a metal foil is transferred and vapor-deposited on the other surface, and a coating liquid containing polyamidopolyamine resin (trade name “Topaz 17 liquid”, manufactured by Toyo Ink Co., Ltd.) using a gravure coater on the metal foil surface is solid content. Was applied at about 0.5 g / m 2 and dried to form a coat layer.
A wet electrophotographic printing machine (trade name “Indigo WS4000”, manufactured by Hewlett-Packard Co.) was used to print a logo and a geometric pattern in seven colors on the surface on the coat layer side. After printing, it was punched into a fan shape in accordance with the container shape to obtain a label used for the composite container of the present invention.

(Label production example 8)
The opaque polyolefin film obtained in Production Example 1 for the label base material was slit to form a 250 mm wide roll. A logo and a geometric pattern were printed on one side of the film using a rotary offset printing press and a four-color UV offset process ink, and a geometric pattern was printed in a single color on the other side. After printing, it was punched into a fan shape in accordance with the container shape to obtain a label used for the composite container of the present invention.

The production example of the composite container of the present invention is shown below.
Example 1
An inner container having an inner diameter of 55 mm and an inner volume of about 60 ml having the cross-sectional shape of FIG. 1 is once applied to an injection molding machine (trade name “ES3000 ELJECT”, manufactured by Nissei Plastic Industry Co., Ltd.) consisting of a resin extruder and a mold clamping device. A mold capable of forming four pieces was attached. After inserting the label obtained in Label Production Example 1 into the female mold of the same mold so that the surface printed with seven colors is in contact with the mold surface and clamping with a clamping force of about 150 t, Propylene homopolymer (trade name “NOVATEC PP MG2T”, manufactured by Nippon Polypro Co., Ltd.) is used as the resin material for the inner container, and this is melt-kneaded with an extruder and injected into the mold at an injection pressure of about 2 t. did. After cooling, the inner container with the label fused to the outer periphery was taken out from the mold. Next, a mold capable of forming four outer containers at a time is attached to another injection molding machine (trade name “ES3000ELJECT”, manufactured by Nissei Plastic Industry Co., Ltd.) consisting of a resin extruder and a mold clamping device. The inner container obtained on the male mold side was inserted by hand and fixed by suction, and then clamped with a clamping force of about 150 tons, and a propylene homopolymer (trade name “Prime” was used as the resin material for the outer container. Polypro J850NA "(manufactured by Prime Polymer Co., Ltd.) was melted and kneaded with an extruder and injected into a mold with an injection pressure of about 2 t to form an outer container. After cooling, this was taken out, As shown in FIG. 2, a composite container 20 was obtained in which the inner container 21, the outer container 22, and the label 23 were fused and integrated. In this composite container, the inner container was transparent, the outer container was transparent, and the label and the container were integrated, so the print on the label was clearly visible without blurring.

(Example 2)
A composite container 20 was obtained in the same manner as in Example 1 except that the label obtained in Label Production Example 2 was used. In this composite container, the inner container was transparent, the outer container was transparent, and the label and the container were integrated, so the print on the label was clearly visible without blurring.

(Example 3)
Except for using the label obtained in Label Production Example 3 and using polyethylene terephthalate (trade name “IP 142B”, manufactured by Bell Polyester Products Co., Ltd.) as the resin material for the inner and outer containers, the same as in Example 1 A composite container in which the outer container, the inner container, and the label were fused and integrated by the apparatus, the mold, and the procedure was obtained. In this composite container, the inner container was transparent and the outer container was transparent, and the label and the container were integrated so that the print on the label could be clearly seen without blurring.

Example 4
Example 1 with the exception of using the olefinic thermoplastic ionomer (trade name “Himiran 1705”, manufactured by Mitsui DuPont Polychemical Co., Ltd.) as the resin material for the outer container, using the label obtained in Label Production Example 4. A composite container in which the outer container, the inner container, and the label were fused and integrated in the same procedure was obtained. In this composite container, the inner container was transparent and the outer container was transparent, and the label and the container were integrated so that the print on the label could be clearly seen without blurring.

(Example 5)
Using the label obtained in Label Production Example 5, a titanium masterbatch was mixed with a propylene homopolymer (trade name “Novatech PP MG2T”, manufactured by Nippon Polypro Co., Ltd.) as a resin material for the inner container. A composite container in which the outer container, the inner container and the label were fused and integrated was obtained in the same procedure as in Example 1 except that the resin composition adjusted to 2% by weight was used. In this composite container, the inner container is opaque white, the outer container is transparent, the label is opaque, the printing on the label can be visually recognized through the outer container, and the printing on the label is blurred because the label and the outer container are integrated. It was something that looked clear.

(Example 6)
Using the label obtained in Production Example 6 of the label and using an olefinic thermoplastic ionomer (trade name “Surlin PC2000”, manufactured by DuPont) as the resin material of the outer container, A composite container in which the inner container and the label were fused and integrated was obtained. In this composite container, the inner container was transparent and the outer container was transparent, and the label and the container were integrated so that the print on the label could be clearly seen without blurring.

(Example 7)
The same procedure as in Example 1 except that the label obtained in Label Production Example 7 was used and an olefin-based thermoplastic elastomer (trade name “ZELAS MC717”, manufactured by Mitsubishi Chemical Corporation) was used as the resin material of the outer container. Thus, the outer container, the inner container and the label were fused and integrated to obtain a composite container. In this composite container, the inner container was transparent and the outer container was transparent, and the label and the container were integrated so that the print on the label could be clearly seen without blurring.

(Comparative Example 1)
A composite container containing a label between an outer container and an inner container was obtained in the same procedure as in Example 1 except that the label obtained in Label Production Example 8 was used. This composite container had insufficient adhesion between the outer container and the label, and a part of the label was lifted. As a result, although the printing on the label can be visually recognized through the container, a part of the printing on the label is blurred and cannot be clearly seen, and the label and the container are not completely integrated. This is because the adhesion between the label printing surface and the outer container in Comparative Example 1 is not sufficiently high as in the present invention of Examples 1-7. This indicates that according to the present invention, it is possible to provide a composite container in which the label and the container are more completely integrated, enabling higher adhesion than in JP 2009-263006.

(Comparative Example 2)
Labels are produced according to the methods described in JP-A 2009-263006, Label Production Examples 1-7. However, a wet electrophotographic printing machine (Indigo WS4000 manufactured by Hewlett-Packard Co., Ltd.) is used instead of printing by an offset printing machine, a letter press printing machine, or a gravure printing machine described in JP-A-2009-263006. ) To print the logo and geometric pattern in 7 colors. Using each of the labels thus obtained, a composite container is manufactured according to the method described in Example 1 of the present specification. In the obtained composite container, the color material on the label printing surface is not sufficiently fixed, and sufficient adhesion between the label printing surface and the outer container is not ensured. The container is not integrated. This means that even if digital printing is performed on a label described in Japanese Patent Application Laid-Open No. 2009-263006, a composite container in which the color material is fixed as in the present invention and the label and the container are completely integrated. Indicates that it cannot be manufactured.

11 Corner of bottom of first resin material part (inner container) 12 Shoulder of first resin material part (inner container) 20 Composite container 21 First resin material part (inner container)
22 Second resin material part (outer container)
23 Label

Claims (18)

An injection molded composite container comprising a first resin material part, a second resin material part, and a label contained between the first resin material part and the second resin material part,
The label has a coat layer in which digital printing is fixed on at least one surface thereof, and both surfaces of the label are fused and integrated with the resin material portions. Injection molded composite container.   The coating layer includes at least one selected from the group consisting of a polyethyleneimine resin, a polyamide polyamine resin, a polyvinyl alcohol resin, a styrene-butadiene copolymer resin, and a vinyl chloride-vinyl acetate copolymer resin as a binder resin. The injection-molded composite container according to claim 1.   2. The label according to claim 1, wherein the label is digitally printed on the coating layer by at least one method selected from the group consisting of a dry electrophotographic system, a wet electrophotographic system, and an ink jet system. Item 3. The injection molded composite container according to Item 1 or 2.   The injection-molded composite container according to any one of claims 1 to 3, wherein the label has the coat layer on both surfaces thereof.   The injection-molded composite according to any one of claims 1 to 3, wherein the label has the coat layer on one side and a heat seal layer on the other side. container.   The heat seal layer is a low density to medium density high pressure polyethylene, linear linear polyethylene, ethylene / α-olefin copolymer, propylene / α-olefin copolymer, ethylene / vinyl acetate copolymer, ethylene / acrylic. It contains at least one selected from the group consisting of an acid copolymer, an ethylene / acrylic acid alkyl ester copolymer, an ethylene / methacrylic acid alkyl ester copolymer, and a metal salt of an ethylene / methacrylic acid copolymer. The injection-molded composite container according to claim 5.   The first resin material is high density polyethylene, medium density polyethylene, polypropylene, poly (4-methylpent-1-ene), polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene succinate, polylactic acid, polystyrene, styrene. -Selected from the group consisting of acrylonitrile resin, acrylonitrile-butadiene-styrene resin, ethylene-vinyl acetate resin, polyamide, polycarbonate, polyvinyl chloride, polyoxymethylene, polymethyl methacrylate, polymethacryl styrene, and polyallyl sulfone A resin composition comprising at least one thermoplastic resin, and the second resin material is high density polyethylene, medium density polyethylene, polypropylene, poly (4-methylpenta- -Ene), elastomer, ionomer, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene succinate, polylactic acid, amorphous polyethylene terephthalate, polystyrene, styrene-acrylonitrile resin, acrylonitrile-butadiene-styrene resin, ethylene-vinyl acetate resin From at least one thermoplastic resin selected from the group consisting of polyamide, polycarbonate, polyvinyl chloride, polyoxymethylene, polyvinyl alcohol, polybutene, polymethyl methacrylate, polymethacrylstyrene, polyarylate, and polyallylsulfone The injection-molded composite container according to claim 1, wherein the resin composition is a resin composition.   The injection molded composite container according to any one of claims 1 to 7, wherein the first resin material part is formed by injection molding and has a shape of a container having a fitting part with a lid.   The injection-molded composite container according to claim 8, wherein the label is disposed along an outer peripheral wall of the first resin material portion having a container shape.   10. The injection-molded composite container according to claim 1, wherein at least one of the first resin material part and the second resin material part is transparent.   The injection-molded composite container according to claim 10, wherein digital printing on the coating layer is visible through the resin material part. A method for manufacturing an injection-molded composite container comprising a first resin material part, a second resin material part, and a label contained between the first resin material part and the second resin material part, ,
(1) A step of performing digital printing on the coat layer of the label having a coat layer on at least one surface;
(2) The label is formed by injecting and molding the first resin material into the first mold after the label is placed and fixed on the inner wall of the first mold on the female mold side and the mold is closed. Forming a fused first resin material part; and
(3) The mold is closed between the first resin material part as a male mold or a part of the male mold and the second mold as a female mold so as to completely enclose the label on the first resin material part. A method for producing an injection-molded composite container comprising: forming a second resin material portion so as to cover a label on the first resin material portion by injecting and molding the second resin material .   13. The injection-molded composite according to claim 12, wherein a plurality of composite containers having different print contents are finally manufactured by digitally printing a plurality of labels while changing the print contents in the step (1). Container manufacturing method.   14. The method of manufacturing an injection-molded composite container according to claim 13, wherein the change of the print content is performed by controlling an electric signal that designates the print content.   A coat layer is formed only on one side of the label, and in the step (2), the surface opposite to the coat layer forming side of the label is in contact with the inner wall of the first mold on the female mold side. It arrange | positions, The manufacturing method of the injection molding composite container as described in any one of Claims 12-14 characterized by the above-mentioned.   The method for producing an injection-molded composite container according to any one of claims 12 to 14, wherein a coat layer is formed on both surfaces of the label.   The method for producing an injection-molded composite container according to any one of claims 12 to 16, wherein the digital printing is performed by a dry electrophotographic system or a wet electrophotographic system.   The method for producing an injection-molded composite container according to any one of claims 12 to 16, wherein the digital printing is performed by an inkjet method.

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