JP2017202866A - Paper cup - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper cup which has superior light shielding properties by using light shielding paper as a packaging material for a body member by making inconspicuous a tint of black to be visualized even when a light shielding layer of the light shielding paper is visualized as a spoon etc., comes into contact with an end of the body member of the paper cup using the light shielding paper.SOLUTION: A body member 4 of a paper cup 1 has, on a surface of a paper layer 10 on a cut inward side of paper shielding paper 8, a non-print surface part 12 where the surface of the paper layer 10 of the light shielding paper 8 appears in stripes while a region along a cup inward end 5 at an end overlap part 13 of the body member 4 is a non-print region, and a black print surface part 11 positioned over an inner periphery of the cup body part other than the non-print surface part 12 and formed by solid printing in black ink, the non-print surface part 12 and black print surface part 11 being covered with a transparent resin layer 14.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a paper cup having a light shielding property that can be used for food packaging.

  2. Description of the Related Art Conventionally, paper cups and containers having a function for preventing light deterioration with respect to contents have been known that use laminated paper in which an aluminum foil or an aluminum layer is laminated on a cardboard base paper as a packaging material.

  However, when the contents are food such as ice cream, a metal detector is often used as part of quality control to inspect for contamination such as metal face chips. It was impossible to produce food cups or containers from packaging materials in which aluminum layers were laminated.

  Also, when disposing of waste after using cups or containers that use a packaging material that has a light-shielding layer consisting of the above aluminum foil or aluminum vapor deposition layer, it is often incinerated, but it melts into the grate of the incinerator. As a result, the metal is entangled as a residue, which not only lowers the incineration efficiency but also damages the grate.

  Under such circumstances, for use in a paper packaging material that is used in a food packaging cup and has a light-shielding property, for example, in Patent Document 1, an intermediate layer adjusted in opacity using carbon black as a pigment is shielded from light. A layered light-shielding paper is proposed in which a paper layer as a sheet paper is stacked on both sides of the light-shielding layer.

  Further, in Patent Document 2, as a body member of a paper-made light-shielding cup, a laminated structure having a layer structure in which a light-shielding layer made of a black ink layer is provided inside a cardboard base paper without covering a metal layer and covered with a milk white polyethylene layer A proposal using paper is shown. And in this patent document 2, the non-printing part of a fixed width is provided in the same layer position as the black ink layer along the periphery of the drum member, and the black ink layer is not exposed on the end surface of the drum member. Techniques for preventing black ink from contacting the contents are also shown.

Japanese Patent Laying-Open No. 2015-086479 JP-A-10-129740

  In the light-shielding paper using carbon black as a pigment, paper fibers in which carbon black is fixed to virgin pulp are mixed in as a light-shielding layer as an intermediate layer so as to exhibit light-shielding properties. When using this shading paper as a packaging material for the body member of the food packaging cup, a transparent and heat-sealable synthetic resin layer is superimposed on each of the paper layers on both sides of the shading paper. A laminated paper is produced and used as a packaging material, and a body member of a paper cup is produced from the packaging material.

  FIG. 4 shows a paper cup barrel member e made of a laminated paper d in which the transparent resin layer c is laminated on the paper layer b on the front and back sides of the light shielding paper a, and the end portions f of the barrel member e are overlapped with each other. The transparent resin layer c opposed at the part is fused, and the end part f in the overlapping part in a state where the body part of the paper cup is formed is shown.

  When the shading paper is used for the body member of the paper cup, the contents come into contact with the end face of the end portion f, and even if a sizing agent (bleeding inhibitor) is applied to the shading paper, the contents contain moisture. In the case of foods and the like, the current situation is that some moisture permeates from the end face of the end portion f.

  However, if the food contains moisture and is taken out with a spoon etc., the spoon is brought into contact with the end f containing moisture and pressure is applied to the paper. The paper fiber portion of the layer b and the light shielding layer g may absorb water and become transparent, and the shade of the light shielding layer g may be visualized in the transparent portion.

  Visualization of the shade of the light-shielding layer does not mean that the carbon component will elute, but consumers who scoop up the food by operating the spoon etc. will see mold and mold when the shade of the light-shielding layer is visualized. It was easy to judge, and there was a possibility that a phenomenon undesirable for a paper cup for food storage use may occur.

  Therefore, in view of the above circumstances, the present invention visualizes the shade of the light shielding layer by contacting a spoon or the like with the end of the body member of the paper cup using light shielding paper having a light shielding layer containing carbon black as a pigment. Even in such a case, the object is to make the black color to be inconspicuous, and an object is to obtain a paper cup having excellent light shielding properties by using the light shielding paper as a packaging material for the body member.

(Invention of Claim 1)
The present invention has been made in consideration of the above problems, and a paper cup in which a body member laminated with a paper layer on both sides of a light-shielding layer having carbon black as a pigment is used as a body member that is bonded with its ends overlapped. Because
The one side of the shading paper has a non-printing area on the one side of the shading paper on the inner side of the cup and the non-printing area in the end part of the trunk member along the inner side of the cup. Has a non-printing surface portion that is exposed in a strip-like shape, and a black printing surface portion formed by solid printing black ink positioned over the inner periphery of the cup body other than the non-printing surface portion,
The present invention provides a paper cup in which the non-printing surface portion and the black printing surface portion are covered with a transparent resin layer to solve the above-mentioned problems.

(Invention of Claim 2)
In the present invention, the non-printing surface portion is a strip-shaped visualization region in which the color of the light-shielding layer is visible through the paper layer by water absorption from the end surface of the body wrapping material, and the visualization region is black. It can be located between the printing surface portions.

(Effect of the invention of claim 1)
According to the invention of claim 1, a non-printing surface portion where the one side of the light shielding paper is exposed by setting a region along the end of the cup at the end portion overlapping portion of the body member to be a non-printing region, Since it has a black printing surface portion formed by solid printing of black ink located over the inner periphery of the cup barrel portion other than this non-printing surface portion, the non-printing surface portion and the black color along the inner end of the cup It will be in the state where the printing surface part was arranged in parallel.

  In the overlapping portion of the end portion, the black color of the black print surface portion becomes more noticeable when the shades of the non print surface portion and the black print surface portion arranged in parallel with the non print surface portion are compared. Therefore, even if moisture soaks from the end face of the inner side of the cup and the soaked end is rubbed with a spoon or the like, the shade of the shading layer can be seen through the rubbed part. , The blackness seen through the non-printed surface portion becomes inconspicuous.

(Effect of the invention of claim 2)
According to the invention of claim 2, since the strip-shaped non-printing surface portion that is the visualization region is located between the black printing surface portions, the shade of the light shielding layer can be seen through the non-printing surface portion as described above. Even if it becomes a state, there exists an effect that the state does not become more conspicuous.

It is explanatory drawing which shows an example of the paper cup which concerns on this invention in the state of a perspective view. It is explanatory drawing which shows the edge part overlapping part of the trunk | drum in an example in the state of a cross section. FIG. 6A is a diagram illustrating the state of darkening. FIG. 7A is an explanatory diagram illustrating how the darkening is noticeable in the embodiment, and FIG. 9B is an explanatory diagram illustrating how the darkening is noticeable in the comparative example. It is explanatory drawing which shows the edge part overlapping part of the trunk | drum of the conventional paper cup in the state of a cross section.

  Next, the present invention will be described in detail based on the embodiments shown in the drawings. In the figure, reference numeral 1 denotes a paper cup according to the present invention. The paper cup 1 is provided with a cylindrical barrel portion 2 which is tapered and opened upward, and a bottom portion 3 which is positioned below the barrel portion 2. The body portion 2 is formed by rolling a body member 4 made of a laminated packaging material upward into a cylindrical shape that opens forward, and overlapping and adhering end portions 5 that face each other in the waistline direction. The bottom 3 uses a disk-shaped bottom material 6 made of a laminated packaging material.

  Then, the flange 7 is formed at the body portion 2 by folding the upper side of the body member 4 outwardly in the radial direction, and the groove portion formed by folding the lower side of the body member 4 inward. The bottom part 3 is connected to the lower part of the trunk part 2 by inserting the periphery of the bottom part 6 that is folded and joining the lower side of the trunk member 4 and the periphery of the bottom part 6.

(Shading paper)
The body 2 of the paper cup 1 is designed so that light from the outside does not deteriorate the contents by passing through the body 2, and the body member 4, which is a packaging material of the body 2, is light-shielding. It is manufactured using the light shielding paper 8 having

  The light shielding paper 8 is formed by laminating a light shielding layer 9 in which carbon black is fixed to a paper fiber as a pigment, and a paper layer 10 positioned on the front and back of the light shielding layer 9. The structure of the paper fiber that has been fixed is interleaved so that the portion of the structure in which the carbon black is fixed to the paper fiber becomes the light shielding layer 9, and the virgin pulp formed by the front and back portions of the light shielding layer 9 A structure of paper fibers is a paper layer 10.

(Body member)
In the body member 4 using the light shielding paper 8, the black printing surface portion 11 formed by solid printing black ink on the surface of the paper layer 10 on the inner side of the cup of the light shielding paper 8, and the black ink. And a non-printing surface portion 12 that allows the surface of the paper layer 10 to be seen without printing. (See Figure 2)

  As shown in FIG. 2, the non-printing surface portion 12 is a non-printing region formed along the end portion 5 that is the inner side of the cup in the end portion overlapping portion 13 of the body member 4. The surface of the paper layer 10 is exposed by forming a narrow band along the end portion 5.

  Further, a transparent resin layer 14 having heat sealability is laminated on the front and back of the light shielding paper 8 by a laminating method and integrated. The non-printing surface portion 12 and the black printing surface portion 11 provided on the surface of the paper layer 10 on the inner side of the cup of the body member 4 are covered with the transparent resin layer 14.

  Since the non-printing surface portion 12 and the black printing surface portion 11 are covered with the transparent resin layer 14, the black printing surface portion 11 cannot be exposed at the end surface of the end portion 5 which is the inner side of the cup of the end overlapping portion 13. The black ink printed on the black printing surface portion 11 is prevented from coming into contact with the contents. In addition, in the edge part overlapping part 13, the transparent resin layers 14 of the edge part 5 which opposes are welded, and the edge parts 5 are bonded together by this.

  As described above, in the body member 4 of the paper cup 1, in the end portion 5 on the inner side of the cup, the region along the end portion 5 of the paper layer 10 on the inner side of the cup is set as a non-printing region. A printing surface portion 12 is formed, and the non-printing surface portion 12 is formed in a narrow band shape with a constant width. The non-printing surface portion 12 is a narrow band-like visualization region that allows the black color of the light shielding layer 9 on the light shielding paper 8 to be seen through when the conditions described below are satisfied.

  Explaining this point, first, if the content to be filled in the paper cup 1 is rich in water such as food, the moisture contained in the content from the end face 5 of the inner end portion 5 of the body member 4 is included. Easy to suck. And when the pressure which rubs with a spoon etc. from the inside of a cup is added to the edge part 5 which absorbed water, a water | moisture content spreads in the paper fiber structure | tissue of the paper layer 10 in the location where the pressure was added, and the paper layer 10 in the location Increases transparency.

  And it will be in the state which can be seen through which the black of the light shielding layer 9 can be seen through the location where the transparency of the paper layer 10 became high. As described above, the non-printing surface portion 12 is a visualization region. In the present embodiment, the non-printing surface portion 12 is a vertical narrow strip extending in the cup height direction and has a constant width. As shown in FIG. 2, the black print surface portion 11a on the side of the end 5 on the inner side of the cup is opposite to the end portion 5 on the inner side of the cup. The black printed surface portion 11b located on the side of the end portion overlapping portion 13 on the side of the end portion 5 side of the end overlapping portion 13 It is located between the side and the part that is facing inward of the cup.

  The non-printing surface portion 12 is a white portion representing the background color of the paper layer 10 and is a visualization region. However, the non-printing surface portion 12 is a black printing surface portion 11 on both sides and is located between the black printing surface portions 11. Therefore, even if the black color of the light shielding layer 9 is seen through the non-printing surface portion 12, it does not stand out and can be prevented from being erroneously determined as mold or dirt. Note that the width dimension of the non-printing surface portion 12 in the cup barrel direction is sufficiently smaller than the width dimension of the end overlapping portion 13 in the cup barrel direction.

(Contrast of darkening IPA penetration test)
Next, as an example and a comparative example, a paper cup using a light shielding paper is formed, and a liquid is poured into the cup, so that the liquid soaks from the end surface of the inner side of the cup at the end overlapping portion of the body portion. A darkening is generated on the inner end side of the cup, and the conspicuousness of darkening is compared between a paper cup having no black printing surface portion and a paper cup having a black printing surface portion, and the results are shown below.

First, print on zebra C acid-resistant cup base paper 260 / m ² (manufactured by Nippon Paper Crecia Co., Ltd.), a light-shielding paper, using a gravure printing machine, and then apply Petrocene 205 (manufactured by Tosoh Corporation) on both sides with an extrusion laminator. A base paper (paper cup packaging) was prepared.
The layer thickness of the petrocene 205 bonded as a transparent resin layer was 20 μm on the front surface and 30 μm on the back surface.
Next, the processed base paper was punched into a cup blank and cup-molded with a cup molding machine.
-As a confirmation method, highly penetrating alcohol (IPA: isopropyl alcohol) was poured into a paper cup (Example, Comparative Example), and how the darkening was noticeable was visually compared.

(Example)
-As for the paper cup molded as an example, as described above, the body member is formed on one side of the inner side of the cup, the non-printing surface part in the form of a narrow band of the non-printing area along the end part on the inner side of the cup, and the gravure And a black printing surface portion in which black ink is solid printed by a printing machine. One side of the cup outer side was normally printed with the gravure printing machine.

(Comparative example)
-About the paper cup shape | molded as a comparative example, the one side inside the cup of a trunk | drum member was made into no printing. One side of the cup outer side was normally printed with the gravure printing machine.

  FIG. 3 shows a state where Example (A) and Comparative Example (B) into which alcohol has permeated are photographed. As shown in the figure, by providing a black printing surface portion, it was possible to reduce the noticeability of the darkened appearance.

(Results of lightness and chromaticity measurement)
Next, a paper cup having a black printing surface portion and a paper cup having a printing surface portion formed by printing with a gray ink having a different hue instead of the black printing surface portion were prepared. Then, using a spectrophotometer X-Rite eXact manufactured by X-Rite Co., Ltd., the brightness and chromaticity were measured in the L * a * b * color system. The results are shown in Table 1.

  The black printing surface portion in the paper cup having the black printing surface portion has a black solid gradation of 100%. Two types of paper cups having a printing surface portion made of gray ink were prepared, one having a gray solid gradation of 100% and the other having a gray solid gradation of 85%. A paper cup having a black printing surface portion and a paper cup having two kinds of gray printing surface portions each have a sample number n = 3. The lightness is L *, and the chromaticity indicating the hue and again is a *, b *.

  If the lightness L * is 50% or less, there is concealment, and if it is 25% or less, sufficient concealment can be ensured. From this point, a paper cup having a black printing surface portion with a black solid gradation of 100% shown in Table 1 has a substantially sufficient concealing property. Therefore, it could be judged that the paper cup according to the present invention is a paper cup having good concealment.

  Next, with a spoon, water was poured into the paper cup of the present invention, and the distance of darkening (width in the waistline direction) generated when the end surface side of the inner end of the cup was rubbed was measured. Shown in The operation of printing the end face side of the cup end with a spoon from bottom to top was defined as one time. Number of samples n = 5

  From the results shown in Table 2, it can be determined that the size of the ink escape from the position of the inner end of the paper cup is preferably 1.5 mm or more. Therefore, the width dimension in the waist direction of the non-printing surface portion is preferably 1.5 to 5 mm. That is, the distance between the overlapping portions of the body members in the bonding of the end portions of the body members of the paper cup is approximately 5 to 6 mm, so the upper limit was set to 5 mm. Therefore, if the width dimension of the non-printing surface portion is in the range of 1.5 to 5 mm, the non-printing surface portion can be accommodated within the dimension of the end portion bonding portion of the body member in a normal paper cup.

DESCRIPTION OF SYMBOLS 1 ... Paper cup 4 ... Body member 5 ... End part 6 ... Bottom surface material 7 ... Flange 8 ... Light shielding paper 9 ... Light shielding layer 10 ... Paper layer 11, 11a, 11b ... Black printing surface part 12 ... Non-printing surface part 13 ... Edge overlapping Part 14 ... Transparent resin layer

Claims (2)

A paper cup made of light-shielding paper in which a paper layer is laminated on the front and back of a light-shielding layer having carbon black as a pigment, and the body member that is bonded with the ends overlapped,
The one side of the shading paper has a non-printing area on the one side of the shading paper on the inner side of the cup and the non-printing area in the end part of the trunk member along the inner side of the cup. Has a non-printing surface portion that is exposed in a strip-like shape, and a black printing surface portion formed by solid printing black ink positioned over the inner periphery of the cup body other than the non-printing surface portion,
A paper cup, wherein the non-printing surface portion and the black printing surface portion are covered with a transparent resin layer.   The non-printing surface portion is a narrow band-like visualization region in which the color of the light-shielding layer is visible through the paper layer by water absorption from the end surface of the body packaging material, and this visualization region is between the black printing surface portions. The paper cup of claim 1, which is located in