JP6235867B2 - Functional paperboard for packaging - Google Patents

Description

  In the present invention, by peeling the film laminated on the pulp layer on the surface of the paperboard provided with a colored layer having functionality in the middle, the colored layer does not appear through the exposed pulp layer, for example, moisture penetrates into the pulp layer. And a functional paperboard for packaging provided with a water-repellent layer.

Conventionally, paper that is a material for various paper containers and packaging such as cups, pouches, wrapping papers, gift paper container boxes, etc., has been given cosmetics or a function of cutting various light rays (visible light, ultraviolet rays, infrared rays) and white. In order to provide a paper having a good appearance such as a high degree, a paper having a colored layer 12 provided in an intermediate layer of paper laminated in three or more layers and bleached pulp layers 11 and 13 provided on the front and back layers is produced. (See FIG. 3).
As the colored layer 12, a method using unbleached pulp or a method of adding various inorganic pigments such as ultramarine blue, prussian blue, red lead, iron oxide, yellow lead, aluminum powder and carbon black to the bleached pulp is used. ing.
Usually, when paper is kept in contact with moisture for a long time even with a large amount of moisture or a small amount, moisture permeates from the front and back surfaces and the end surface, and a phenomenon in which the transparency is improved as compared with the dried state occurs.
When such a phenomenon occurs in the base paper in which the colored layer 12 is provided in the conventional intermediate layer, the colored layer 12 can be seen through because the bleached pulp layers 11 and 13 on the front surface or the back surface are translucent. It affects the appearance, and in particular when used for packaging food containers, the user may have a poor hygiene impression.
In particular, as an example in which these phenomena remarkably appear, when the liquid contents and moisture in the contents permeate from the end surface of the base paper of the cup bonding portion, the surface of the laminated resin layer after peeling the top seal of the cup and A case where moisture permeates from a portion where a part of the bleached pulp layer has disappeared to become translucent and the colored layer can be seen through is mentioned.
On the other hand, the applicant of the present invention disclosed in Japanese Patent Application Laid-Open No. 2012-229046 is a light-shielding paper cup formed using a laminated light-shielding paper having a light-shielding printing layer between two base papers. The outer side of the base paper is laminated with a light-shielding printing layer via a resin layer, the sum of the basis weights of the two base papers of the laminated light-shielding paper is 150 to 350 g / m ² , and the basis weight of one base paper is By setting the basis weight of the other base paper to 1.3 times or more, the rigidity of the larger basis weight prevents warping and twisting of the smaller basis weight, and a light-shielding printing layer is formed on any base paper. The paper cup can be easily formed by concealing, and when the lid is peeled off, peeling is caused in the layer of the base paper to prevent exposure of the light-shielding print layer.
However, in the above configuration, it is not sufficient to minimize the change in the hue of the base paper layer visible from the outside by masking the color of the light-shielding print layer.
Japanese Patent Laid-Open No. 6-143877 discloses a configuration in which white or the like is applied as a colored layer to the outside of the shielding layer as a method for eliminating the darkening on the surface of the paper. It could not be solved until it became transparent and the color of the shielding layer was transparent.

JP 2012-229046 A JP-A-6-143877

  The problem to be solved by the present invention is that when moisture permeates the pulp layer on the surface of the functional paperboard provided with the colored layer, the colored layer is masked even if the pulp layer is seen through, and the appearance is impaired. An object of the present invention is to provide a functional paperboard for packaging having a water repellent layer interposed therebetween.

In order to solve the above-mentioned problems, the present invention provides
In a functional paperboard for packaging having a colored layer between two pulp layers,
Between the pulp layer and the colored layer, a water-repellent layer that repels moisture penetrating from the pulp layer to which moisture can adhere during use is provided,
The colored layer is made of pulp containing an inorganic pigment,
The water repellent layer is composed of a pulp layer containing a water repellent or a synthetic resin layer .

In the present invention, a water repellent layer that repels moisture penetrating from the pulp layer is provided between the pulp layer and the colored layer, so that the penetration of moisture is blocked by the water repellent layer and the color of the colored layer cannot be seen through. Since it did in this way, a colored layer does not see through a pulp layer.
As a result, when the film laminated on one pulp layer of the packaging functional paperboard is peeled off for use, or when the pulp layer is exposed, moisture is present in the pulp layer exposed by peeling of the laminate film. Since the color of the colored layer does not appear when it penetrates and sees through, the cosmetic appearance of the appearance is maintained, and the user is not given a bad impression on the appearance.

It is explanatory drawing of the functional paperboard for packaging of Example 1. FIG. It is explanatory drawing of the functional paperboard for packaging of a reference example . It is explanatory drawing of the functional paperboard for packaging of a prior art example.

In this invention, between the pulp layer and the colored layer, the permeation of moisture penetrating from the pulp layer from which the laminate film has been peeled is repelled by the water repellent layer to mask the colored layer, whereby the colored layer is interposed via the pulp layer. Was not seen through.
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

The functional paperboard 10 for packaging of Example 1 shown in FIG. 1 has a surface pulp layer 1, a colored layer 2 containing an inorganic pigment having intermediate layer functionality, and a back pulp layer 3. A water repellent layer 4 is provided between the pulp layer 1 and the colored layer 2 of the surface layer and / or the pulp layer 3 and the colored layer 2 of the back layer.
In the illustrated example, the water-repellent layer 4 is provided in a pair so as to sandwich the colored layer 2, but either one may be provided.
In this embodiment, a transparent film F is laminated on the surface side of the bleached pulp layers 1 and 3.

In this embodiment, the pulp layers 1 and 3 were bleached pulp layers, but in the present invention, bleaching or coloring agents such as dyes, pigments, and optical brighteners were added and bleached or colored. It may be bleached or uncolored (unbleached).
The colored layer 2 may be black, which has a light-shielding property, or red, which has ultraviolet absorption, as in the conventional colored layer.
The colored layer 2 may be a pulp mixed with a pigment.
The water repellent layer 4 is a synthetic resin layer or pulp layer to which a compound generally mixed during paperboard papermaking such as rosin, AKD, ASK, etc. is added as a water repellent agent during papermaking. It is preferable to add 1.3 times or more of the water repellent agent during paper making.

As a result, when at least a part of the laminate film F is peeled off during use, the surface of the pulp layer 1 is peeled off integrally with the laminate film F. It is preferable to set the internal bond strength of the pulp layer so as to remain on the 10 side.
When a part of the pulp layer 1 is exposed or peeled off, moisture such as water droplets penetrates from the pulp layer 1 into the board.
At that time, since the infiltrated moisture is blocked by the water repellent layer 4, further infiltration is prevented, and deterioration of the appearance can be prevented.
Moreover, since the pulp layers 1 and 3 are pulp layers of conventional components, they do not affect the fixability of various coating agents and the adhesiveness with the extrusion laminate resin.

  In this example, in order to make the front and back the same, the pulp layer and the water repellent layer are arranged symmetrically with the colored layer 2 as the center, so the plate material 10 can be used in the same way from either the front or back side, In the present invention, as described above, the water repellent layer 4 may be provided only on the side where moisture enters.

  Moreover, although the case where the laminate film F was laminated on the pulp layer 1 (3) was illustrated in the present embodiment, the pulp layer 1 (3) may be directly exposed without being laminated.

[Reference example]
The functional paperboard 10 for packaging shown in FIG. 2 has a surface pulp layer 1, an intermediate colored layer 2, and a back pulp layer 3 as reference examples not included in the examples . Between the pulp layer 1 and the colored layer 2 and / or the back pulp layer 3 and the colored layer 2, a water-insoluble white colored layer that masks the color of the colored layer 2 is provided as a concealing layer 5.
In the illustrated example, the hiding layer 5 is provided as a pair so as to sandwich the colored layer 2, but either one may be provided.
Also in this embodiment, a transparent laminate film F is laminated on the surface side of the pulp layers 1 and 3.
Here, the pulp layers 1 and 3, the colored layer 2, and the laminate film F are the same as those in the above-described embodiment, and thus description thereof is omitted.

The concealing layer 5 is composed of a white colored layer in which a white pigment such as titanium oxide, zinc white, lithopone, or lead white is mixed with a pulp layer during paper making.
Since the pigment is a powder and a water-insoluble colorant, it does not penetrate even when water enters.

Thereby, even when the laminate film F is peeled off and the surface side of the bleached pulp layer 1 (3) is peeled off due to moisture permeation as described above, and the remaining part is transparent, the color of the concealing layer 5 is changed. It is possible to prevent the appearance of the paperboard 10 from being damaged by masking the colored layer 2 from being seen through.
Also in this case, the concealing layer 5 may be formed between the bleached pulp layer 1 (3) and the colored layer 2 on the side where water penetrates at least.

The functional paperboard 1 for packaging of Example 1 may be formed by mixing papermaking compounds so that each layer is formed at the papermaking stage.
In addition, the present invention is not limited to the above-described embodiments, and it goes without saying that various design changes can be made without departing from the scope of the present invention.

1 Pulp layer (surface layer, surface layer side)
2 Colored layer 3 Pulp layer (back layer, back layer side)
4 Water repellent layer 5 Shielding layer 6 Synthetic resin layer 10 Functional paperboard for packaging

Claims (2)

In a functional paperboard for packaging having a colored layer between two pulp layers,
Between the pulp layer and the colored layer, a water-repellent layer that repels moisture penetrating from the pulp layer to which moisture can adhere during use is provided,
The colored layer is made of pulp containing an inorganic pigment,
The functional paperboard for packaging , wherein the water repellent layer comprises a pulp layer containing a water repellent or a synthetic resin layer .   The functional paperboard for packaging according to claim 1, wherein the water repellent is made of rosin, AKD or ASK.

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