JP2016068568A - Manufacturing process for paper-made package, and paper-made package manufactured by the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing process for paper-made package in which a paper-made package such as box and bag, over which a three-dimensional decorative fabrication with excellent design is imparted, is produced by foaming the whole exterior surface without causing problems such as poor appearance and quality decrease during the thermal foaming and fabrication.SOLUTION: The manufacturing process for paper-made package includes: forming a laminated paper 3 having a thermoplastic resin layer 2 to be foamed by heating, laminated over the outer surface side of a paper substrate 1; heating the laminated paper 3 and foaming the thermoplastic resin layer 2 to form a foamed layer 2a; and forming a paper-made package using the foamed layer 2a-formed laminate paper 3.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a method for producing a paper package and a paper package obtained by the method.

  Containers and packaging of merchandise displayed at retail stores are often decorated to appeal to consumers for the appeal of the merchandise. Since paper is excellent in printability, it is possible to decorate a paper package by various printing methods. However, since paper is extremely low in plasticity and hardly deforms, it is difficult to apply a three-dimensional decorative process to the paper package to add irregularities.

As a three-dimensional decoration processing method for a paper package, embossing as described in Patent Document 1 is known. This embossing uses an embossing ruler blade and a female die having a recess formed by a peripheral inner surface of the thickness of the paper base material from the periphery of the embossing ruler blade. A paper base material is sandwiched between and pressed to give unevenness.
However, since the paper has low plasticity as described above, there is a problem that if the unevenness is increased, the paper breaks and it is difficult to perform a three-dimensional decorative process excellent in design. In addition, as described in Patent Document 1, the embossing process usually requires that the embossing plate made up of the embossed ruled blade and the female mold and the embossing process are separate processes. Therefore, there is a problem that the manufacturing time and the cost required for the embossed plate are increased.

As another three-dimensional decoration processing method for the paper packaging body, as described in Patent Document 2, a step of applying foaming ink to paper serving as a base material, and a pair of projections and depressions provided on the surface A method is known which is performed by a process of embossing paper as a substrate with a roll and a heating / foaming process of foaming a printed layer with foamed ink.
Similarly to the method described in Patent Document 1, the method described in Patent Document 2 breaks the paper when the unevenness is increased by embossing, and gives a three-dimensional decorative process excellent in design. It is difficult to provide unevenness enough to express sufficient design properties with foamed ink, it is necessary to increase the amount of ink applied very much, the printing method is limited, the amount of ink used increases, There were problems such as. In addition, a process for applying foamed ink to paper, a process for embossing paper as a base material with a pair of rolls with irregularities on the surface, and a heating / foaming process for foaming the printed layer with foamed ink are required. Therefore, there is a problem that the manufacturing time and the cost required for the embossed plate are increased.

On the other hand, as described in Patent Document 3, a thermoplastic resin layer is laminated on a paper base material, a foam-suppressing ink is applied to the thermoplastic resin layer, and heated after container molding to form a thermoplastic resin layer. There is a method in which a foamed layer is formed by foaming, and a foamed portion and a foaming suppression portion are provided in the foamed layer.
In the method described in Patent Document 3, since the thermoplastic resin layer laminated on the paper is foamed and deformed by heating rather than embossing the paper using a mold such as an embossed plate, Unevenness can be easily provided, and a three-dimensional decoration process excellent in design is possible.
In addition, the foamed layer in which the thermoplastic resin layer is foamed after heating by printing the foam-suppressing ink on the surface of the thermoplastic resin layer laminated on the paper substrate, instead of embossing with a mold, in the normal printing process Since the surface is provided with unevenness due to the foamed portion and the foaming suppression portion, there is no need for a mold such as an embossed plate, and a three-dimensional decoration process can be easily performed. In addition, complex and fine designs that are difficult to emboss with a mold are possible, and it is possible to freely combine unevenness and printing such as full-color single color, full-color multicolor printing, partial printing, or no printing. For example, it is possible to perform decorative processing with excellent design.

Japanese Patent Laid-Open No. 2005-14405 JP 2002-254588 A Japanese Patent No. 5549959

As described above, the method described in Patent Document 3 is excellent as a method for performing a three-dimensional decoration process with excellent design on the surface of a paper container, but is a paper on which a three-dimensional decoration process is performed by foaming the outer surface. The container is a cup, and the cup can be processed upright or inverted in the heating device without contacting the foamed surface inside the heating device. Is foamed.
However, when the paper package is in the shape of a box or bag, when it is heated and foamed after being formed into a box or bag shape, its outer surface will always be in contact with the heating device, and will be in contact with the heating device. There are problems such as appearance defects and quality degradation in the areas that are present, and degradation in manufacturing efficiency.

Inventors and others have conducted research and research to solve such problems, whereby a laminated paper in which a thermoplastic resin layer is laminated on a paper base is first heated to foam the thermoplastic resin layer, and then a box or We focused on forming a bag-like package.
However, when a folded sheet is attached to foamed laminated paper and a package is formed by box making or bag making, the foamed layer has a large cushioning effect, so the effect of the crease is not fully manifested and processing troubles occur. It is assumed that this causes problems such as occurrence of defects and appearance defects.
Also, in box making and bag making processes, when bonding or heat sealing using an adhesive such as hot melt, poor bonding occurs in the bonding part or heat seal part because of the large cushioning properties of the foam layer, It is assumed that problems such as poor appearance and leakage of contents occur.
The inventors of the present invention have made the present invention by paying attention to providing a foaming suppression portion in the foamed layer by further conducting research and study in order to solve such an assumed problem.

The object of the present invention is to make paper packaging such as boxes and bags that have been subjected to a three-dimensional decoration process that foams the entire outer surface and is excellent in design without causing problems such as poor appearance and reduced quality during heat foaming. It is providing the manufacturing method of the paper packaging body which manufactures a body, and the paper packaging body obtained by the method.
Another object of the present invention is to provide a three-dimensional decoration process with excellent design by foaming the entire outer surface without causing problems such as processing troubles and appearance defects during box making and bag making. Another object of the present invention is to provide a method for producing a paper package for producing a paper package such as a box or a bag, and a paper package obtained by the method.

In order to achieve the above object, the invention described in claim 1
A method for producing a paper package having a foam layer on the outer surface side, characterized in that the following steps (a) to (c) are included in this order.
(A) The process of forming the laminated paper which laminated | stacked the thermoplastic resin layer made to foam by heating on the outer surface side of a paper base material.
(A) A step of heating the laminated paper to foam the thermoplastic resin layer to form a foamed layer.
(C) A step of forming a paper package using the laminated paper on which the foam layer is formed.

  According to the first aspect of the present invention, a box or bag that has been subjected to a three-dimensional decoration process that is foamed on the entire outer surface and is excellent in design without causing problems such as poor appearance and reduced quality during the heat foaming process. A paper package such as can be produced.

  The invention described in claim 2 is characterized in that the thermoplastic resin layer according to claim 1 is appropriately subjected to foam suppression means, and a decorative foam portion and a foam suppression portion are provided on the surface of the foam layer. Yes.

  According to invention of Claim 2, since the unevenness | corrugation by a foaming part and a foaming suppression part is provided to a foaming layer, the pattern and pattern by an uneven part can be expressed, and the box and bag which were excellent in the design property A paper package such as can be produced.

  According to a third aspect of the present invention, in the thermoplastic resin layer of the laminated paper that forms the paper packaging body according to any one of the first or second aspect, a crease in the paper packaging body is provided. The foam suppression means is provided in a range corresponding to any one or more of the part, the bonding part, and the heat seal part, and the foam suppression part is provided.

According to the invention described in claim 3, when a folded body is attached to the foamed laminated paper and a package is formed by box making or bag making, the crease is a foam suppression part. Therefore, the effect of the crease can be sufficiently exhibited, and a paper package can be manufactured without causing problems such as processing troubles and poor appearance.
Also, in box making and bag making, when bonding or heat sealing using an adhesive such as hot melt, the bonding part or heat seal part is a foam suppression part, so the bonding part or Adhesive failure occurs in the heat seal portion, and a paper package can be manufactured without causing problems such as poor appearance and leakage of contents.

  The invention according to claim 4 is a paper package obtained by the method for manufacturing a paper package according to any one of claims 1 to 3.

  According to invention of Claim 4, paper-made packaging bodies, such as a box and a bag which gave the three-dimensional decoration process excellent in the designability, can be obtained.

  According to the present invention, without causing problems such as poor appearance and quality deterioration during the heat foaming process, and causing problems such as processing troubles and poor appearance during the box making process and the bag making process. In addition, it is possible to obtain a paper package such as a box or a bag which is foamed on the entire outer surface and subjected to a three-dimensional decoration process excellent in design.

It is a partially expanded sectional view which shows an example of the laminated paper which forms the paper packaging body manufactured with the manufacturing method of the paper packaging body which concerns on this invention. It is a top view which shows an example of laminated paper in case the paper-made packaging bodies manufactured by this invention are boxes. It is a partially expanded sectional view which shows the state which made the thermoplastic resin of the laminated paper shown in FIG. 1 foam. It is a perspective view which shows the paper-made packaging body formed with the laminated paper shown in FIG.

Hereinafter, an example of an embodiment of a method for producing a paper package according to the present invention and a paper package obtained by the method will be described in detail with reference to the drawings.
FIG. 1 is a partially enlarged cross-sectional view showing an example of a laminated paper forming a paper package manufactured by the method for manufacturing a paper package according to the present invention, and FIG. 2 is a box of the paper package manufactured by the present invention. FIG. 3 is a partially enlarged sectional view showing a state in which the thermoplastic resin of the laminated paper shown in FIG. 1 is foamed, and FIG. 4 is formed of the laminated paper shown in FIG. It is a perspective view which shows the made paper packaging body.

  In the manufacturing method of the paper packaging body of this example, first, a laminated paper 3 for forming a paper packaging body A by laminating a thermoplastic resin layer 2 which is foamed by heating on the outer surface side of the paper base 1 is prepared. Form. If necessary, the laminated paper 3 may be formed by laminating a thermoplastic resin layer 4 that is not foamed on the inner surface side of the paper substrate 1. In the laminated paper 3 formed in this example, a thermoplastic resin layer 4 that is not foamed is laminated on the inner surface side of the paper substrate 1.

  The paper base material 1 constituting the laminated paper 3 of this example is made of softwood, hardwood, non-wood fiber, or the like. More specifically, chemical pulp such as kraft pulp, fine pulp, thermomechanical pulp, mechanical pulp such as chemithermomechanical pulp, or recycled pulp manufactured from a sheet-like substance made of waste paper or paper fiber, etc. . As used paper, for example, it can be applied to newspapers, flyers, further magazines, coated magazines, thermal recording paper, pressure-sensitive recording paper, imitation paper, colored fine paper, copy paper, computer output paper, or mixed old paper of these. . Paper raw materials 1 can be obtained by making these raw materials by a normal paper making process.

The basis weight of the paper substrate 1 is preferably in the range of 50 to 500 g / m ² , but is not limited thereto. In addition, the water content is preferably 5 to 10% by weight in order to secure the necessary foaming amount of the thermoplastic resin layer 2 and prevent the occurrence of overfoaming. When the moisture content is 10% by weight or less, the moisture contained in the paper base material evaporates by heating, and the softened thermoplastic resin layer is excessively extruded to the outside of the paper base material 1 by water vapor, and the effect of foaming is effective. Can be suppressed.

Further, the density of the paper substrate is preferably 0.6 g / cm ³ or more, and particularly preferably 1.0 g / cm ³ or more. When the density of the paper base material 1 is 0.6 g / cm ³ or more, water vapor is difficult to escape from the end face of the paper base material 1, and the foam thickness is larger than that of the paper base material 1 having the same basis weight and low density. Therefore, it is preferable. In order to increase the basis weight of the low density paper base material 1 in order to obtain the same foaming pressure as that of the high density paper base material 1, it is necessary to use a large amount of material. On the other hand, when the density of the paper substrate 1 is 0.6 g / cm ³ or more, it is not necessary to use a large amount of material, and the cost is excellent.

  It is preferable that the freezing degree of the pulp which manufactures the paper base material 1 (CSF) is 100-500 ml. In the case of 500 ml or less, it is difficult for water vapor to pass through the inside of the paper base material 1, and it becomes difficult for water vapor to escape from the end surface of the paper base material 1. When the freeness is 100 ml or more, the power consumption for beating the pulp to lower the freeness is not increased, and the cost is excellent.

  The thermoplastic resin layer 2 which is foamed by heating laminated on the outer surface side of the paper substrate 1 thus obtained and becomes a foamed layer and the thermoplastic resin which is not foamed, ie, becomes a non-foamed layer laminated on the inner surface side. The thermoplastic resin layer that forms the layer 4 has a lower melting point of the thermoplastic resin that forms the thermoplastic resin layer 2 that becomes the foamed layer than the melting point of the thermoplastic resin that forms the thermoplastic resin layer 4 that becomes the non-foamed layer. Is preferred.

  As a thermoplastic resin which forms the thermoplastic resin layer 2 used as a foam layer, a low density polyethylene is preferable and its melting | fusing point is preferably 90 degreeC or more and less than 110 degreeC. Moreover, as a thermoplastic resin which forms the thermoplastic resin layer 4 of a non-foamed layer, medium-density polyethylene with a high melting point, high-density polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, trimethyl pertene, etc. can be used. The melting point of the thermoplastic resin forming the thermoplastic resin layer 4 may be slightly higher than the melting point of the thermoplastic resin forming the thermoplastic resin layer 2 of the foamed layer, and is generally preferably 110 ° C. or higher. When moisture is vaporized by heating by using such a resin structure, only the foamed surface can be foamed.

However, the melting point of the thermoplastic resin that forms the thermoplastic resin layer 2 that becomes the foamed layer does not necessarily need to be lower than the melting point of the thermoplastic resin that forms the thermoplastic resin layer 4 that becomes the non-foamed layer. You may make it suppress the foaming of the thermoplastic resin layer 4 by giving the resin layer 4 the foaming suppression means mentioned later.
Moreover, as a method of laminating the thermoplastic resin layers 2 and 4 on the outer surface side and the inner surface side of the paper base material 1, a dry laminating method, a melt extrusion laminating method, a wet laminating method, or the like can be used. In this example, lamination is performed using a melt extrusion laminating method.

  In the present invention, the amount of foaming of the laminated paper 3 depends on the absolute amount of moisture contained in the paper substrate 1. That is, if the basis weight of the paper base material 1 is large, the total amount of moisture contained in the paper base material is also large, so that the low melting point thermoplastic resin layer 2 can be foamed more. If the basis weight of the paper substrate 1 is large (the amount of water is large) and the low melting point thermoplastic resin layer 2 is thick, the foam thickness can be increased. If the basis weight of the paper substrate 1 is large and the thermoplastic resin layer 2 having a low melting point is thin, the resin thickness becomes too thin in the middle of foaming, the foam cell is easily broken, and the appearance deteriorates. A combination of a large paper substrate 1 and a thin thermoplastic resin layer 2 is not preferred. On the other hand, if the basis weight of the paper substrate 1 is small and the thermoplastic resin layer 2 having a low melting point is thick, the water content of the paper substrate is so small that the thick thermoplastic resin layer 2 cannot be sufficiently foamed. It is economical, and a combination of a paper substrate having a small basis weight and a thick thermoplastic resin layer 2 is not preferable. For this reason, it is preferable to adjust suitably the basic weight of the paper base material 1, and the thickness of the thermoplastic resin layer 2 of a low melting point.

  Next, the laminated paper 3 thus formed is heated to foam the thermoplastic resin layer 2 laminated on the outer surface side of the paper substrate 1. As conditions for foaming the thermoplastic resin layer 2, it is preferable to heat in a range of about 110 ° C. to 140 ° C. for about 40 seconds to 6 minutes with a heat dryer. By this heating, moisture contained in the paper base material 1 is vaporized, and the thermoplastic resin layer 2 laminated on the outer surface side of the paper base material 1 foams to form a foam layer 2a.

  In this example, foaming suppression means 5 is appropriately applied to the surface of the thermoplastic resin layer 2 laminated on the outer surface side of the paper substrate 1 in the previous step of heating the laminated paper 3 (see FIG. 1), which will be described later. As described above, the decorative foaming portion and the foaming suppression portion are formed on the surface of the foamed layer 2a formed by the thermoplastic resin layer 2 foamed by heating.

  In this example, a foam suppression ink that forms a coating film that is difficult to transmit water vapor is used as the foam suppression means 5, and as shown in FIG. 1, the foam suppression ink is applied to the surface of the thermoplastic resin layer 2 to suppress foaming The ink application part 5a is provided, and the foam suppression layer described later is formed in the foam layer 2a by suppressing the foaming of the foam layer 2a by the foam suppression ink application part 5a.

As a material of the foam suppression ink, polyamide resin, nitrified cotton, vinyl acetate resin, urethane resin, polyvinyl chloride resin, acrylic resin, Kent resin, etc. are used alone or in combination of two or more, for example, The foam suppression ink disclosed in Patent Document 3 is used.
In addition to the resin, the foam suppression ink contains a colorant, an auxiliary agent, and a solvent as necessary.
The foam suppression ink application portion 5a provided on the surface of the thermoplastic resin layer 2 by application of the foam suppression ink is provided using a general printing method such as gravure printing or flexographic printing, but may be provided by other means. Good.

Furthermore, in this example, the thermoplastic resin layer 2 of the laminated paper 3 forming the paper packaging body A is any one of a crease part, a bonding part, and a heat seal part depending on the shape of the paper packaging body A. Foam suppression means 5 is applied to a range corresponding to the above-described parts to form a foam suppression portion described later.
FIG. 2 shows an example of the laminated paper 3 when the paper package A to be manufactured is a box, and the laminated paper 3 is punched before heating, and the front panel 8, the top panel 9, the back panel 10, and the bottom panel. 11, a laminating portion 12, a cover panel 13 connected to the left and right of the top panel 9, a front panel 8, and a folded panel 14 connected to the left and right of the back panel 10.

  And in the surface of the thermoplastic resin layer 2 of the laminated paper 3 formed in such a blank, it respond | corresponds to each site | part of the bonding part 12, the cover panel 13, the folding panel 14, and the crease part 15 between each panel. Foam suppression means 5 (the hatched portion in FIG. 2) is applied to the entire surface of the range so as to form a foam suppression portion described later.

The laminated paper 3 formed in this way is heated with a heat dryer as described above. When the paper package A to be produced is a box, the laminated paper 3 is punched out according to the unfolded shape of the box. After forming into a blank, it is heated.
In this example, since the foam suppression ink application part 5a which becomes the foam suppression means 5 is suitably provided on the surface of the thermoplastic resin layer 2 laminated on the outer surface side of the paper substrate 1, as shown in FIG. The foamed layer 2a formed by the foamed thermoplastic resin layer 2 is formed with a foam suppression part 7 in which foaming of the part provided with the foam suppression ink application part 5a is suppressed and a foamed part 6 by foaming of other parts. Then, the foam suppression part 7 becomes a concave part and the foam part 6 becomes a convex part.

Next, after the laminated paper 3 in which the thermoplastic resin layer 2 is foamed by heating is cut into a necessary shape, the paper package A is formed by assembling.
In this example, since the laminated paper 3 is formed in a blank, the box-shaped paper package A shown in FIG. 4 can be formed using a conventional box making machine.
In the present invention, a paper package can be formed from a single sheet or a small number of laminated papers 3, and the shape of the paper package A and the method for forming the same are not particularly limited.

  As described above, according to the method for manufacturing a paper package according to the present invention, first, the laminated paper 3 is formed by laminating the thermoplastic resin layer 2 to be foamed by heating on the outer surface side of the paper base 1, The laminated paper 3 is heated to foam the thermoplastic resin layer 2 to form the foamed layer 2a, and the paper package A is formed using the laminated paper 3 on which the foamed layer 2a is formed. Without causing problems such as poor appearance and poor quality, it is possible to obtain a paper package A such as a box or bag that is foamed on the entire outer surface and subjected to a three-dimensional decoration process having excellent design.

  Moreover, since the obtained paper packaging body A has the flexible foam layer 2a with sufficient thickness, it is excellent in cushioning properties and the protection performance of the contents is improved. Furthermore, since the foamed layer 2a has a heat insulating effect, it is excellent in heat insulation and cold insulation performance. Moreover, in this example, since the thermoplastic resin layer 4 is laminated | stacked also on the inner surface side, it is excellent in water resistance compared with a normal paper packaging body.

Moreover, in this example, since the foam suppression part 5 is suitably given to the thermoplastic resin layer 2, and the foaming part 6 and the foaming suppression part 7 for a decoration are formed in the surface of the foaming layer 2a, the foaming part 6 and the foaming layer 2a Concavities and convexities are provided by the foaming suppression unit 7, and a pattern or a pattern by the concavities and convexities can be expressed. In this example, since the foam suppression ink is used as the foam suppression means 5 and the foam suppression ink is applied to the surface of the thermoplastic resin layer 2 to provide the foam suppression ink application part 5a, it is difficult to emboss with a mold. It is also possible to design complicated or fine patterns and patterns. Furthermore, aesthetics can be imparted by using a colored foam-suppressing ink.
Moreover, grip property can be improved and it becomes easy to have by controlling the foaming pattern of the foaming layer 2a by the foam suppression ink application part 5a.

  In this example, any one of a crease part, a bonding part, and a heat seal part is applied to the thermoplastic resin layer 2 of the laminated paper 3 forming the paper package A according to the shape of the paper package A. Since the foam suppression means 5 is applied to the range corresponding to the above-mentioned parts and the foam suppression part 7 is provided, the effect of the crease can be sufficiently expressed, and the paper package A can be easily formed. It is possible to obtain a paper package A having an excellent design without appearance defects.

  Further, in the case of box making and bag making, when bonding or heat sealing is performed using an adhesive such as hot melt, the bonding portion or the heat sealing portion is the foam suppression portion 7, so the bonding portion Alternatively, it is possible to obtain a paper package A that has no adhesion failure or appearance failure in the heat seal portion, and has no problems such as leakage of contents.

DESCRIPTION OF SYMBOLS 1 Paper base material 2 Thermoplastic resin layer 2a Foam layer 3 Laminated paper 4 Thermoplastic resin layer 5 Foam suppression means 5a Foam suppression ink application part 6 Foam part 7 Foam suppression part 8 Front panel 9 Top panel 10 Rear panel 11 Bottom panel 12 Laminating part 13 Lid panel 14 Folding panel 15 Folding ruled part A Paper packaging

Claims (4)

A method for producing a paper package having a foam layer on the outer surface side, the method comprising the following steps (a) to (c) in this order.
(A) The process of forming the laminated paper which laminated | stacked the thermoplastic resin layer made to foam by heating on the outer surface side of a paper base material.
(A) A step of heating the laminated paper to foam the thermoplastic resin layer to form a foamed layer.
(C) A step of forming a paper package using the laminated paper on which the foam layer is formed.   The method for producing a paper package according to claim 1, wherein foaming suppression means is appropriately applied to the thermoplastic resin layer, and a foaming part for decoration and a foaming suppression part are provided on the surface of the foamed layer.   Inhibition of foaming in the thermoplastic resin layer of the laminated paper forming the paper packaging body in a range corresponding to any one or more of a crease, a bonding portion, and a heat seal portion of the paper packaging body The method for producing a paper packaging body according to claim 1, wherein means is provided and a foaming suppression portion is provided. A paper packaging body obtained by the method for producing a paper packaging body according to any one of claims 1 to 3.

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