Package

Abstract

To provide a paper package of roll-shaped sanitary tissue paper which has good packaging strength and excellent appearance being unlikely to have wrinkles or up-floating surface (including waving and hardening).SOLUTION: There is provided a package of roll-shaped sanitary tissue paper in which rolls of sanitary tissue paper are stored in a packaging bag. The packaging bag is made of gusset packaging base material, which has a pair of opposing flat parts and a gusset part folded inward from both ends of the flat part, the packaging base material includes paper base material, the upper surface part of the flat part is sealed, the rolled sanitary tissue paper is arranged in an n×n square matrix (n represents an integer of 1 or more) in plan view, and the difference (a-b) and sum (a+b) between the width a of the flat part of the gusset packaging bag and the gusset width b of the gusset packaging bag with respect to the radius R of the rolled sanitary tissue paper, both fulfil the relationship between formulas (1) and (2). 0<(a-b)≤20n (1) πR+(n-1)×4R<(a+b) (2)SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a package made of a packaging substrate including a paper substrate, which contains a plurality of roll-shaped paper products, such as toilet paper rolls. [Background technology]

[0002] Conventionally, there is known a package in which a paper product, which is a roll of sanitary thin paper such as a toilet paper roll or a kitchen paper roll, is packaged in a packaging film such as polyethylene. For example, Patent Document 1 discloses a package in which a gusset is folded symmetrically into a cylindrical film such as polyethylene to form a main body (gusset packaging bag), the upper part of which is folded flat to form a gripping part, and which packages a paper product, which is a roll of sanitary thin paper. In recent years, the problem of plastic waste has become more serious worldwide, and from the viewpoint of protecting the global environment by reducing, for example, microplastics in the ocean, it is desired to reduce the use of plastics (synthetic resins) and to change the packaging material from synthetic resin films to other materials. As for packages for packaging paper products, packages using a paper base material as the packaging material and packaging paper products have been proposed. For example, Patent Document 2 discloses a package in which a paper product is packaged using a packaging base material in which a heat seal layer for sealing is laminated on a paper base material. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2004-269010 A [Patent Document 2] Patent Publication No. 2021-070501 Summary of the Invention [Problem to be solved by the invention]

[0004] In the case of a gusset packaging bag in which a gusset is folded symmetrically into a cylindrical packaging base material made of paper and the upper part is joined, the packaging base material in the packaging bag may peel off when storing multiple rolls of sanitary tissue paper because the flexibility is small compared to resin films. In addition, the folds are easily noticeable, and depending on the width of the flat part of the gusset packaging bag, the folds are easily visible to consumers when the package containing the rolls of sanitary tissue paper is displayed, which can damage the appearance. Furthermore, the package is prone to wrinkles and surface lifting, and this tendency is more pronounced in packages containing multiple rolls of sanitary tissue paper stacked in multiple layers. If there are wrinkles, especially on the finished surface of the package, during transportation or display, the appearance of the package is damaged, the appeal of the product to consumers is reduced, and purchasing motivation is easily damaged.

[0005] The present invention has been made in consideration of the above circumstances, and has an object to provide a package for roll-shaped sanitary tissue paper made of packaging substrates including a paper substrate, in which the joints between the packaging substrates are less likely to peel off, and which has an excellent appearance with particularly little wrinkles and surface lift (including waviness and stiffness). As a result of extensive research, the inventors have discovered that by setting the relationship between the width of the flat part of a gusset packaging bag of a packaging base material including a paper base material and the gusset width within a specific range, it is possible to obtain a package that is easy to store rolled sanitary tissue paper, is less likely to peel off at the joints between the packaging base materials, and has an excellent appearance with less wrinkles and surface lifting (including waviness and stiffness), and have completed the present invention. [Means for solving the problem]

[0006] The present invention has the following configuration. <1> A package comprising a plurality of rolls of sanitary tissue paper housed in a packaging bag, The packaging bag is a gusset packaging bag made of a packaging base material having a pair of opposing flat surfaces and a gusset portion folded inward from both ends of the flat surfaces, The packaging substrate comprises a paper substrate; The upper surface of the planar portion is sealed, The roll-shaped sanitary thin paper is arranged in a square matrix of n × n pieces (n is an integer of 1 or more) in a plan view, With respect to the radius R of the rolled sanitary thin paper, A package of rolled sanitary thin paper, in which the difference (ab) and the sum (a+b) between the width a of the flat portion of the gusset packaging bag and the gusset width b of the gusset packaging bag satisfy both of the following formulas (1) and (2). 0 < (a b ) ≦ 20 n (1) πR+(n-1)×4R < (a+b) (2) <2> The sum (a+b) of the width a of the flat portion of the gusset packaging bag and the gusset width b is 4nR+10 or less, where R is the radius of the rolled sanitary thin paper. <1> Packaging of. <3> The width a of the planar portion of the gusset packaging bag and the gusset width b satisfy the following formulas (3) and (4) with respect to the radius R of the rolled sanitary thin paper. <1> or <2> Packaging of. 2nR-0.35R ≦ a ≦ 2nR+20 (3) (n-1)×2R < b ≦ 2nR (4) <4> The width a of the flat portion is smaller than 2nR with respect to the radius R of the rolled sanitary thin paper. <1> or <3> Packaging of. <5> The roll-shaped sanitary tissue paper is any one of a toilet paper roll, a kitchen paper roll, and a hand towel roll. <1> ~ <4> Any of the above packaging materials. <6> The rolled sanitary thin paper has approximately the same dimensions, the width of the rolled sanitary thin paper is 100 mm or more and 260 mm or less, and the radius R of the rolled sanitary thin paper is 50 mm or more and 70 mm or less. <5> Packaging of. <7> The packaging substrate has a heat seal layer. <1> ~ <6> Any of the above packaging materials. <8> The ratio of the basis weight of the paper substrate to the basis weight of the packaging substrate is greater than 50% and less than or equal to 100%. <1> ~ <7> Any of the above packaging materials. Effect of the Invention

[0007] According to the present invention, it is possible to provide a package for rolled sanitary tissue paper made of a packaging base material including a paper base material, which makes it easy to store the rolled sanitary tissue paper, is less likely to peel off at the joints between the packaging base materials, has less wrinkles and surface lift (including waviness and stiffness), and has an excellent appearance. [Brief description of the drawings]

[0008] [Figure 1] 1 is a front view of a gusset packaging bag according to an embodiment of the packaging body of the present invention. FIG. [Diagram 2] 1 is a top cross-sectional view of a gusset packaging bag when it is partially unfolded. FIG. [Diagram 3] 1 is a perspective view showing the upper part of a gusset packaging bag when the gusset packaging bag is partially unfolded. FIG. [Figure 4] 1 is a perspective view showing one embodiment of a packaging body of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The packaging body of the present invention is a packaging body in which a plurality of roll-shaped sanitary thin paper sheets are stored in a packaging bag, the packaging bag being a gusset packaging bag of a packaging base material having a pair of opposing flat portions and a gusset portion folded inward from both ends of the flat portions, The packaging substrate comprises a paper substrate; The upper surface of the planar portion is sealed, The roll-shaped sanitary thin paper is arranged in a square matrix of n × n pieces (n is an integer of 1 or more; the same applies below) in a plan view, With respect to the radius R of the rolled sanitary thin paper, The difference (ab) and the sum (a+b) between the width a of the flat portion of the gusset packaging bag and the gusset width b of the gusset packaging bag satisfy both of the following formulas (1) and (2). 0 < (a b ) ≦ 20 n (1) πR+(n-1)×4R < (a+b) (2) The units of a and b above are both mm.

[0010] The packaging bag constituting the packaging body of the present invention is a gusset packaging bag made of a packaging base material having a pair of opposing flat surfaces and a gusset portion folded inward from both ends of the flat surfaces, and the upper surface of the flat surfaces is sealed, and the sealed portion may serve as a gripping portion.

[0011] The packaging substrate includes a paper substrate. When the packaging substrate is formed into a package, printing may be applied to the outer surface side. The packaging substrate may be an overcoated paper to ensure waterproofing. The packaging substrate may further have a heat seal layer, an adhesive layer, etc., which will be described later.

[0012] The basis weight of the packaging material is 45 g / m 2 More than 160g / m 2 It is preferable that the thickness is less than 70 g / m 2 More than 140g / m 2 Less than 90 g / m is more preferable. 2 More than 120g / m 2 The following is even more preferred: When the basis weight of the packaging substrate is low, the basis weight of the paper substrate contained in the packaging substrate is generally low, the constituent pulp fibers are small, the interfiber bonding is small, and the strength is low and the substrate tends to be easily torn. In addition, as the basis weight of the packaging substrate decreases, the basis weight of the heat seal layer and adhesive layer described later also generally decreases, so that the joints between the packaging substrates tend to peel off easily. On the other hand, when the basis weight of the packaging substrate is high, wrinkles and surface lifting (including wavy and stiff feeling) are likely to occur, and the appearance of the package tends to be poor. In addition, when the seal layer is a heat seal layer, heat transfer becomes insufficient during the heat seal process, and the heating temperature of the heat seal layer decreases, making it difficult to obtain a good bonding strength. When the basis weight of the packaging substrate is within the above range, the packaging substrate has an appropriate strength and is not easily torn, and the appearance of the package is excellent. In addition, when the seal layer is a heat seal layer, the joints between the packaging substrates in the package 100 are not easily peeled off. The basis weight of the packaging substrate is the total basis weight of the heat seal layer, adhesive layer, etc., which will be described later, and the paper substrate.

[0013] The paper base material contained in the packaging base material is obtained by papermaking a slurry containing a pulp component, which is a fiber raw material. Examples of the pulp component include wood pulp such as softwood kraft pulp, hardwood kraft pulp, groundwood pulp, thermomechanical pulp, and chemithermomechanical pulp; non-wood pulp such as bamboo, reed, straw, kenaf, and bagasse; and waste paper pulp such as newspapers, flyers, rough magazines, coated magazines, thermal recording paper, pressure-sensitive recording paper, imitation paper, colored wood-free paper, copy paper, computer output paper, and mixed waste paper of these. These may be used alone or in combination of two or more at any ratio. The cooking method and bleaching method in the pulp production are not particularly limited. Furthermore, various commonly used additives such as wet strength agents, fillers, sizing agents, dry strength agents, retention aids, and coloring pigments may be added to the paper base material as necessary.

[0014] The paper base material has a basis weight of 25 g / m 2 More than 85g / m 2 It is preferable that the thickness is less than 30 g / m 2 More than 70g / m 2 Less than 35 g / m is more preferable. 2 More than 60g / m 2 The following is even more preferable. When the basis weight of the paper substrate is within the above range, the packaging substrate has good flexibility, softness and strength. In addition, the ratio of the basis weight of the paper substrate to the basis weight of the packaging substrate is greater than 50%.

[0015] The thickness of the packaging base material can be appropriately selected taking into consideration circumstances specific to gusset packaging, such as flexibility, cost, ease of opening, abrasion resistance to the rolled sanitary thin paper contained inside, and flexibility that allows fingers to be passed through a finger hole provided in the handle as needed to avoid excessive strain on the fingers when carrying the product, as well as the type and number of rolled sanitary thin paper contained inside. Generally, a thickness of 80 μm or more and 130 μm or less is preferable, 90 μm or more and 120 μm or less is more preferable, and 95 μm or more and 115 μm or less is even more preferable.

[0016] The basis weight of the packaging substrate and paper substrate can be measured in accordance with JIS P 8124 (1998), and the thickness of the packaging substrate and paper substrate can be measured in accordance with JIS P 8118 (2014).

[0017] The means for forming the gusset packaging bag is not particularly limited, and may be a method of forming an adhesive layer on a packaging base material in advance, forming a gusset packaging bag with the adhesive layer facing inside, and bonding the two together, or may be a method of forming a gusset packaging bag using a packaging base material with a heat seal layer with the heat seal layer facing inside, and bonding (sealing) by heating. Also, the upper surface of the flat part of the gusset packaging bag may be sealed to form a grip part, and the means for forming the grip part is not particularly limited.

[0018] The adhesive constituting the adhesive layer is not particularly limited, and examples thereof include ethylene-based adhesives, urethane-based adhesives, polyester urethane-based adhesives, polyether urethane-based adhesives, acrylic adhesives, styrene-acrylic adhesives, polyester-based adhesives, polyamide-based adhesives, polyvinyl acetate-based adhesives, epoxy-based adhesives, rubber-based adhesives, etc. Among these, ethylene-based adhesives such as ethylene-vinyl acetate copolymers and ethylene-ethyl acrylate copolymers are preferred from the viewpoint of their use as hot melt adhesives. The adhesive layer can be formed by applying an adhesive to the paper substrate by a method such as roll coating, gravure roll coating, kiss coating, etc. The adhesive layer can be formed on the entire surface of the paper substrate, or only on a part of the surface, for example, on the part where the paper substrates are laminated and joined together. The position, size, and proportion of the adhesive layer on the surface of the paper substrate can be appropriately set.

[0019] The material constituting the heat seal layer is not particularly limited, and may be, for example, a material that exhibits heat sealability, such as a polyolefin resin or other thermoplastic resin.Specific examples of the material include low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, ethylene-α-olefin copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-methacrylic acid copolymer, ionomer, polypropylene, propylene-ethylene copolymer, polypropylene-based resin obtained by graft-polymerizing or copolymerizing unsaturated carboxylic acid, unsaturated carboxylic anhydride, ester monomer, etc., with polypropylene, styrene-acrylic copolymer, amorphous polyester, etc.These may be used alone or in combination of two or more.

[0020] The heat seal layer can be formed, for example, by a method of forming a film of the material constituting the heat seal layer, such as a polyolefin resin, on a paper substrate by an extrusion method; a method of laminating a film containing the material constituting the heat seal layer on a paper substrate using a known heat seal processing device (lamination processing device); or a method of applying a solution in which the material constituting the heat seal layer is dissolved or dispersed in a solvent onto the paper substrate by a method such as roll coating, gravure roll coating, or kiss coating.

[0021] It is preferable to form the gusset packaging bag using a paper base material having a heat seal layer as the packaging base material, from the viewpoints of ensuring the strength, water resistance, breathability, etc. of the gusset packaging bag, and of minimizing the occurrence of wrinkles and surface lifting (including wavyness and stiffness) when used as a package, and thus tending to have an excellent appearance. The heat seal layer may be formed on the entire surface of the paper base material, or may be formed only on a part of the surface, for example, on the part where the paper base materials are laminated and joined together. The position, size, and proportion of the heat seal layer on the surface of the paper base material that the heat seal layer occupies can be appropriately set.

[0022] In the packaging body of the present invention, a paper base material having a heat seal layer can be preferably used as the packaging base material forming the gusset packaging bag. Among them, laminated paper, coated paper, and coated paper in which a material constituting a heat seal layer such as polyethylene or polypropylene is laminated (laminated or coated) are more preferable as the packaging base material. Specific examples of the paper substrate include, but are not limited to, transparent paper such as glassine paper, and one-sided glossy paper such as pure white paper.

[0023] The packaging substrate constituting the gusset packaging bag may have, in addition to the heat seal layer or adhesive layer, other layers such as a water vapor barrier layer, an oxygen barrier layer, a print layer, a printability improving layer, an overprint layer, a light blocking layer, etc. The other layer may be provided, for example, between the paper substrate and the heat seal layer or the adhesive layer, or on the surface that will become the uppermost surface of the package, and may be one layer or two or more layers.

[0024] In the packaging body of the present invention, the roll-shaped sanitary thin paper is preferably any one of a toilet paper roll, a kitchen paper roll, and a hand towel roll. The number of plies in the rolled sanitary thin paper is not particularly limited and can be appropriately selected from 1 to 3. In addition, the rolled sanitary thin paper may be embossed. It is preferable that the rolled sanitary thin paper have approximately the same dimensions. The width (height) of the rolled sanitary thin paper is preferably 100 mm or more and 260 mm or less. Specifically, when the rolled sanitary thin paper is a toilet paper roll, the width (height) of the rolled sanitary thin paper is preferably 100 mm or more and 130 mm or less, and more preferably 105 mm or more and 125 mm or less. Furthermore, when the rolled sanitary thin paper is a kitchen paper roll or a hand towel roll, the width (height) of the rolled sanitary thin paper is preferably 200 mm or more and 260 mm or less, and more preferably 210 mm or more and 250 mm or less. The radius R of the rolled sanitary thin paper is preferably 50 mm or more and 70 mm or less, and more preferably 52 mm or more and 65 mm or less. Here, the radius R of the roll of sanitary thin paper means the average value of all the rolls in the package. More specifically, it is the average value of the outer perimeter of the roll of sanitary thin paper divided by 2π, assuming that the cross section of each roll in the package is a perfect circle.

[0025] The toilet paper roll may be a core-type toilet paper roll in which a strip of toilet paper is wound around a paper tube, or a coreless toilet paper roll, also called a coreless toilet paper roll. The thickness of one ply of toilet paper is 80 μm or more and 230 μm or less, and the basis weight per ply is 10.0 g / m 2 More than 25.0g / m 2 It is preferable that: In the case of a kitchen paper roll, which is a paper core wrapped with a strip of kitchen paper, for example, the thickness of the two plies is 300 μm to 800 μm, and the basis weight per ply is 15.0 g / m. 2 More than 30.0g / m 2 Examples include the following. The basis weight can be measured based on JIS P 8124 (1998), and the thickness is a value measured in accordance with ISO12625-3 (2014) under the same conditions after sufficient humidity conditioning under the conditions of JIS P 8111 (1998).

[0026] Hereinafter, specific embodiments of the present invention will be described with reference to the drawings, however, the scope of the invention is not limited to these illustrated examples.

[0027] 1 is a front view of a packaging bag 10 constituting the package of the present invention. The packaging bag 10 is a gusset packaging bag having a pair of opposing flat portions 1 and 3, and gusset portions 2 and 4 that are folded inward in a V-shape from both ends 1a, 1a' (3a, 3a') of each of the flat portions 1 and 3, which are both side portions connecting the pair. 2 is a top cross-sectional view of packaging bag 10, which is a gusset packaging bag, when it is unfolded, and Fig. 3 is a perspective view showing the upper part of the gusset packaging bag 10, which is a gusset packaging bag, when it is unfolded. The packaging bag is formed with gusset portions 2 and 4 folded inward between flat portions 1 and 3. As shown in Figs. 2 and 3, such a gusset packaging bag has four side surfaces formed from a cylindrical bag body, and two opposing surfaces (corresponding to gusset portions 2 and 4) are folded inward toward the center (fold line Z) to form a structure. The direction L connecting both ends 1a, 1a' (3a, 3a') of each flat portion 1, 3 is referred to as the "horizontal direction." In addition, in the packaging bag 10, the side where a gripping portion 5 described later is formed is referred to as the "upper end," and the open end side opposite the upper end is referred to as the "lower side."

[0028] As shown in FIG. 1, the upper end sides of the flat portion 1 and the flat portion 3 are overlapped with each other and sealed approximately parallel to the horizontal direction L, specifically at two places near the upper end edge and below the upper end edge (seal S in FIG. 1), to form the grip portion 5 between these seals S. It is preferable to form a gusset packaging bag using a paper base material with a heat seal layer so that the opposing surfaces of the flat portion 1 and the flat portion 3 are heat seal layers. The grip portion 5 may be provided with one or more finger holes. FIG. 1 shows, for example, a case in which a finger hole is provided by cutting out the center between both ends 1a, 1a' (3a, 3a') in the grip portion 5, forming an oval handle 6 long in the horizontal direction L. Alternatively, a plurality of circular, elliptical, egg-shaped, or other finger holes large enough to easily insert an adult's finger may be provided at a position at a predetermined distance from approximately the center of the horizontal direction L, i.e., the width direction, and at a predetermined distance from the upper side of the grip portion 5. The bottom side is left open so that a roll of sanitary tissue paper can be stored in. After the open bottom is opened and the roll of sanitary tissue paper is inserted and stored, the bottom is sealed by heat sealing or the like.

[0029] When forming the packaging base material into a gusset packaging bag, a known method can be applied. For example, as shown in Figs. 2(a) to (c) and 3(a) to (c), portions HS-a, HS-b, and HS-1 to HS-4 are first joined by heat sealing or adhesive to form a cylindrical body. In detail, as shown in Figures 2(a) and 3(a), for example, the gusset packaging bag 10 is formed by forming a single packaging base material into a cylindrical shape, folding the gusset portion to form a pair of flat portions and a pair of gusset portions, and heat sealing or bonding at HS-a near the center of the flat portions to form a cylindrical body. Next, with the gusset portion folded inside the bag to flatten it, the upper end sides of the pair of flat portions are sealed to form the grip portion 5. Alternatively, as shown in Figures 2(b) and 3(b), a single sheet of wrapping paper base material is formed into a cylindrical shape, the gusset portion is folded to form a pair of flat portions and a pair of gusset portions, and the flat portions and the side surfaces of the gusset portions, HS-b, are heat sealed or bonded to form a cylindrical shape, and then the gusset portions are folded inside the bag to flatten it, and the upper end sides of the pair of flat portions are sealed to form the grip portion 5. Alternatively, as shown in Figures 2(c) and 3(c), four packaging substrates may be heat-sealed at locations HS-1 to HS-4 corresponding to both ends 1a, 1a' (3a, 3a') of the flat portions 1, 3 to form a tubular body having a pair of flat portions and a pair of gusset portions. In this case, the packaging substrate constituting the flat portions and the packaging substrate constituting the gusset portions may be made of the same material or different materials. Next, the gusset portions are folded inside the bag to flatten it, and the upper end sides of the pair of flat portions are sealed to form the grip portion 5.

[0030] In the present invention, the width a of the flat portion of the gusset packaging bag refers to the width of the flat portion of the gusset packaging bag as shown in Figures 2 and 3. When there is a joint at the end of the flat portion as shown in Figures 2(b), (c) and 3(b), (c), the width a of the flat portion of the gusset packaging bag refers to the portion excluding the joint. The gusset width b refers to the sum of the gusset portions 2b and 2b' or the sum of the gusset portions 4b and 4b' that are folded as shown in Figures 2 and 3 and constitute the side portion described below. Like the width a of the flat portion, when there is a joint at the end of the flat portion as shown in Figures 2(b), (c) and 3(b), (c), the gusset width b refers to the portion excluding the joint. One of the pair of flat parts of the gusset packaging bag is the finished surface, i.e., the front display surface of the package as a product, and the gusset part is the gusset surface, i.e., the display surface for accessories such as product instructions, etc. When the gusset packaging bag is formed by heat sealing or bonding one of the flat parts as shown in Fig. 2(a), the flat part on the side without such heat seal part, etc., is the finished surface.

[0031] FIG. 4 is a perspective view showing a package 100 according to an embodiment of the present invention. The package 100 is a package in which rolled sanitary thin paper such as a toilet paper roll or a paper towel roll is arranged in a square matrix of n×n pieces in a plan view, stacked in one or more stages, and packaged in a gusset packaging bag of the packaging base material shown in FIG. 1 to FIG. 3, which has a pair of flat parts and a gusset part folded inward from both ends of the flat parts, and the upper surface part of the flat part is sealed to form a grip part. The package 100 includes a bag body part 20 in which the rolled sanitary thin paper is stored, and a grip part 5 provided on the upper part of the bag body part 20. The grip part 5 may have a finger hole 6 formed therein as described above.

[0032] In the package 100 according to the present embodiment, the rolled sanitary thin paper is arranged in a square matrix of n×n pieces in a plan view in the gusset packaging bag 10 having the above-mentioned configuration, so that the adjacent rolled sanitary thin paper contacts each other at the body surface and the end faces are flush with each other, and one end face is enclosed toward the gripping portion 5. That is, in the package 100, the gusset portion folded inward of the gusset packaging bag 10 is opened to form a pair of flat portions 1 and 3 and adjacent side portions 2 and 4, and the bag body portion 20 contains one or more layers of rolled sanitary thin paper arranged in a square matrix of n×n pieces in a plan view. n is preferably an integer of 4 or less, more preferably an integer of 2 to 3, and even more preferably n is 2. When the rolled sanitary thin paper is contained in multiple layers, the number of layers is preferably 2 or 3. FIG. 4 shows an embodiment in which n=2 and the rolled sanitary thin paper is stacked in two layers.

[0033] In the packaging body of the present invention, the difference (ab) and the sum (a+b) between the width a of the flat portion of the gusset packaging bag and the gusset width b of the gusset packaging bag, relative to the radius R of the roll-shaped sanitary thin paper, both satisfy the relationships of the following formulas (1) and (2). 0 < (a b ) ≦ 20 n (1) πR+(n-1)×4R < (a+b) (2) The units of a, b, and R are all mm.

[0034] More specifically, in formula (1), the difference (ab) between the width a of the planar portion of the gusset packaging bag and the gusset width b is preferably 10n or less, more preferably 8n or less. Also, the difference (ab) is preferably n or more, more preferably 2n or more. In other words, the difference (ab) is preferably set in the range of n or more and 10n or less, more preferably 2n or more and 8n or less. If the difference (ab) exceeds 20n, the shape of the bottom surface when the packaging bag is made deviates from the shape of the rolled sanitary thin paper when it is arranged in an n × n square matrix, making it difficult to insert the rolled sanitary thin paper into the gusset packaging bag. Furthermore, in formula (2), the sum (a+b) of the width a of the flat portion of the gusset packaging bag and the gusset width b is greater than πR+(n-1)×4R. πR+(n-1)×4R corresponds to the outer circumference of n×n rolls of sanitary thin paper arranged in an n×n square matrix, divided by 2. If the sum (a+b) is smaller than πR+(n-1)×4R, it is difficult to insert the roll of sanitary thin paper into the gusset packaging bag, and further, there is a risk that the joints between the packaging base materials will peel off when the roll of sanitary thin paper is inserted and stored. Furthermore, the sum (a+b) of the width a of the flat portion of the gusset packaging bag and the gusset width b is preferably 4nR+10 or less, more preferably 4nR or less, and even more preferably 4nR-10 or less. 4nR corresponds to the sum of the diameters of one example of rolled sanitary thin paper arranged in an n x n square matrix multiplied by 2, and when the sum (a+b) is 4nR+10 or less, the package has an excellent appearance and the occurrence of wrinkles and surface lifting (including waviness and stiffness) is reduced.

[0035] It is preferable that the width a of the planar portion of the gusset packaging bag and the gusset width b satisfy the relationships of the following formulas (3) and (4) with respect to the radius R of the roll-shaped sanitary thin paper. 2nR-0.35R ≦ a ≦ 2nR+20 (3) (n-1)×2R < b ≦ 2nR (4) The units of a, b, W and R are all mm.

[0036] More specifically, in formula (3), the width a of the flat portion of the gusset packaging bag is more preferably 2nR-0.25R or more, and even more preferably 2nR-0.20R or more. The width a of the flat portion of the gusset packaging bag is more preferably 2nR+10 or less, and even more preferably 2nR+5 or less. Here, the calculated minimum value of the width a of the flat part of the gusset packaging bag (a min ) is expressed by the following formula (5). Here, the width a of the flat part of the gusset packaging bag is a minIf set at this value, it becomes difficult to insert the rolled sanitary tissue paper into the gusset packaging bag when producing the package, and the heat-sealed portion of the gusset packaging bag (HS portion in Figure 2 or Figure 3) is likely to peel off or tear, which tends to affect the productivity of the package. a min =2πR×2×1 / 8+(n-1)×2R (5)

[0037] In formula (4), the gusset width b is more preferably equal to or greater than (n-1)×2R+R, and even more preferably equal to or greater than (n-1)×2R+1.5R. The gusset width b is more preferably equal to or less than 2nR-2n, and even more preferably equal to or less than 2nR-4n. By designing the width a of the flat part of the gusset packaging bag and the gusset width b to satisfy the above relationship, the resulting package has excellent appearance and the occurrence of wrinkles and surface lifting (including waviness and stiffness) is reduced. In addition, when inserting and storing rolls of sanitary tissue paper arranged in a square matrix of n x n pieces in a plan view, the joints between the packaging base materials are less likely to peel off.

[0038] It is particularly preferable that the width a of the flat portion of the gusset packaging bag is smaller than 2nR with respect to the radius R. 2nR corresponds to the sum of the diameters of an example of rolled sanitary thin paper arranged in an n×n square matrix, and by making the width a of the flat portion of the gusset packaging bag smaller than 2nR, the package has an excellent appearance and reduces the occurrence of wrinkles and surface lifting (including waviness and stiffness).

[0039] In the present invention, by satisfying the relationship defined in the present invention between the width a of the flat portion of the gusset packaging bag and the gusset width b, particularly in the embodiment of the gusset packaging bag in which the flat portion and the gusset portion are heat-sealed at the four sides of the package (corresponding to the fold portions), the joints between the packaging base materials are unlikely to peel off even when rolls of sanitary thin paper arranged in an n×n square matrix in a plan view are inserted and stored. In addition, the appearance of the resulting package is excellent, and the occurrence of wrinkles and surface lifting (including waviness and stiffness) is likely to be reduced.

[0040] A known method can be applied to the procedure of gusset packaging. For example, as shown in Fig. 2(a) to Fig. 2(c), a packaging base material is heat-sealed to create a gusset packaging bag having a pair of opposing flat parts and a gusset part folded inward from both ends of the flat parts, and the upper surface part of the flat parts is sealed to form a grip part, and the opening at the lower end (bottom side opening) of the gusset packaging bag is expanded, and the rolled sanitary thin paper to be packaged is inserted from there in a state in which it is arranged and lined up in a square matrix of n × n pieces in a plan view, and then the bottom side opening is heat-sealed to seal it. When inserting the rolled sanitary thin paper in a state in which it is arranged and lined up in a square matrix of n × n pieces in a plan view, it is preferable to expand it while holding the four corners corresponding to the connection parts between the pair of flat parts and the gusset part at the opening at the lower end, and insert it.

[0041] Although the packaging body of the present invention has been described above, the present invention is not limited to the configuration of the above-mentioned embodiment. For example, the packaging body of the present invention may have any other configuration added to the configuration of the above-mentioned embodiment, or may be replaced with any configuration that exhibits a similar function. EXAMPLES

[0042] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these. [Examples 1 to 16, Comparative Examples 1 to 6] 1. Creating the packaging A single-sided glazed paper having a heat seal layer was used as the packaging base material, and a pair of flat portions and a gusset portion were heat sealed at the portions corresponding to the four side edges of the packaging bag (corresponding to HS1 to HS4 in FIG. 2(c)), and then the top surface of the flat portion was sealed to form a gripping portion to create a gusset packaging bag. Next, various rolled sanitary thin papers were inserted in n (pieces) and m (tiers) as shown in Table 1, and the bottom opening was heat sealed to create a package. Table 1 also shows the radius R and width W of the rolled sanitary thin paper, the basis weight, thickness and paper base ratio of the packaging base material, the width a of the flat portion of the gusset packaging bag, and the gusset width b. The width a of the flat surface of the gusset packaging bag and the gusset width b were measured with a ruler. The width W of the rolled sanitary thin paper was measured with a ruler while the roll was upright. The radius R of the rolled sanitary thin paper was calculated by measuring the outer circumference of the roll with a tape measure and dividing the measured value by 2π, assuming that the cross section of the roll is a perfect circle. The units of a, b, W, and R are all mm. The measurements were performed in an environment conforming to ISO187 (temperature 23±1°C, relative humidity 50±2%).

[0043] 2. Evaluation of packaging 2-1. Appearance of the package Five packages obtained from each Example and Comparative Example were lined up side by side on a display shelf with no gaps between them, and the appearance of the finished surface was visually observed from the front. The presence or absence of wrinkles and surface lifting (including waviness and stiffness) was evaluated by 20 testers according to the following criteria. <Evaluation criteria> 4: Good. 3: There are slight wrinkles, but they are not very noticeable. 2: Some wrinkles or surface lifting are observed, but within the acceptable range. 1: Wrinkles and surface lifting are noticeable.

[0044] Productivity When preparing the packages, the ease of inserting the rolled sanitary tissue paper into the gusset packaging bag and the position of the joints on the side (HS1 to HS4 in Figure 2(c)) of 10 packages obtained by heat sealing the bottom opening were visually checked and evaluated according to the following criteria. <Evaluation criteria> 5: Easy to insert, 9 or more had side joints in roughly the same position 4: It was easy to insert, and the side joints of 6 to 8 pieces were in almost the same position. 3: When inserting, the edge of the packaging bag was sometimes touched, but the joints of the side parts of six or more pieces were in almost the same position. 2: The insertion was easy, but the joints on the sides were in roughly the same position in only five or fewer pieces. 1: Could not be inserted easily.

[0045] 2-3. Durability For five packages obtained in each Example and Comparative Example, one tester visually inspected the heat-sealed portions (HS1 to HS4 in FIG. 2(c)) on the side of the gusset package for peeling and tears in the packaging base material. 4: There was absolutely no peeling of the heat seal or tearing of the packaging base material. 3: There were some slight peelings in the heat sealed areas, but this was within the acceptable range. 2: Many peelings were observed in the heat-sealed areas. 1: Peeling occurred over the entire heat-sealed area. The evaluation results are shown in Table 1.

[0046] [Table 1]

[0047] As shown in Table 1, the packages of Examples 1 to 16, which satisfy the provisions of the present invention, were all rated 2, 3, or 4 in "appearance of package" (four-point scale), and had few wrinkles and surface lifting (including waviness and stiffness). In addition, in terms of "productivity" (5-point scale), Examples 7 and 10, which had a slightly small (a+b), were rated 3, meaning that they sometimes came into contact with the edge of the packaging bag when inserted, but Examples 1 to 6, 8, 9, and 11 to 16 were rated 4 or 5, meaning that the roll-shaped sanitary tissue paper was easy to insert into the gusset packaging bag and there was little variation in the position of the joint on the side. Furthermore, the "durability" (4-point scale) was rated 3 or 4 for Examples 1 to 16, and peeling of the heat-sealed portion was slight and within the acceptable range.

[0048] In Comparative Example 1, (a+b) was smaller and (ab) was larger than in Examples 1 to 4. Although (a+b) in Comparative Example 1 was within the range specified by the present invention, it was smaller than in Examples 1 to 4, and (ab) was outside the range specified by the present invention, and since the shape of the bottom surface of the gusset packaging bag deviated from the state in which four rolls of sanitary thin paper were arranged in a square matrix, it was difficult to insert the roll of sanitary thin paper into the gusset packaging bag. In addition, because it was difficult to insert, many peeled-off portions were observed in the heat-sealed portion.

[0049] In Comparative Examples 2, 3, and 6, (a+b) was outside the range specified by the present invention, making it difficult to insert the rolled sanitary thin paper into the gusset packaging bag, and peeling occurred over the entire heat-sealed portion. In Comparative Example 3, (ab) was within the range specified by the present invention, but was larger than Comparative Example 2, and compared with Comparative Example 2, the shape of the bottom surface of the gusset packaging bag deviated from the state in which four rolled sanitary thin paper were arranged in a square matrix, making it more difficult to insert the rolled sanitary thin paper into the gusset packaging bag.

[0050] In Comparative Example 4, the width a of the flat portion of the gusset packaging bag was longer than in Examples 3 and 9, and therefore (ab) was larger. Although (a+b) in Comparative Example 4 was within the range specified in the present invention, it was larger than in Examples 3 and 9, and (ab) was outside the range specified in the present invention, so that a gap occurred between the packaging bag and the rolled sanitary thin paper, there was considerable variation in the position of the joints of the side portions, and wrinkles and lifting of the surface were noticeable. In Comparative Example 5, (ab) is outside the scope of the present invention, and the shape of the bottom surface of the gusset packaging bag deviates from the state in which four rolls of sanitary thin paper are arranged in a square matrix, making it more difficult to insert the roll of sanitary thin paper into the gusset packaging bag. [Industrial Applicability]

[0051] The package of the present invention has good packaging strength and excellent appearance, and is useful as an environmentally friendly package that reduces the use of plastics. [Explanation of symbols]

[0052] 1,3 Plane part 2,4 Gusset section 5 Gripping part 6 Finger hole 10 Gusseted packaging bag 20 Bag body 100 packages S Seal Part Z Gusset fold line P Rolled sanitary tissue paper

Claims

1. A package comprising a plurality of rolls of sanitary tissue paper housed in a packaging bag, The packaging bag is a gusset packaging bag of a packaging base material having a pair of opposing flat portions and a gusset portion folded inward from both ends of the flat portions, the packaging base material includes a paper base material, the upper surface portion of the flat portions is sealed, and the rolled sanitary thin paper is arranged in a square matrix of n x n pieces (n represents an integer of 1 or more) in a planar view, and the difference (a-b) and the sum (a+b) of the width a (mm) of the flat portions of the gusset packaging bag and the gusset width b (mm) of the gusset packaging bag relative to the radius R (mm) of the rolled sanitary thin paper both satisfy the relationships of the following formulas (1) and (2). 0 < (a-b) ≦ 20n (unit: mm) (1) πR + (n-1) × 4R < (a + b) (unit: mm) (2)

2. The package according to claim 1, wherein the sum (a+b) of the width a of the planar portion of the gusset packaging bag and the gusset width b is 4nR+10 or less, where R is the radius of the rolled sanitary thin paper.

3. The packaging body according to claim 1, wherein the width a of the planar portion of the gusset packaging bag and the gusset width b satisfy the following formulas (3) and (4) with respect to the radius R of the rolled sanitary thin paper. 2nR-0.35R≦a≦2nR+20 (unit: mm) (3) (n-1) x 2R < b ≤ 2nR (unit: mm) (4)

4. The packaging body according to claim 1 , wherein the width a of the planar portion is smaller than 2nR, where R is the radius of the rolled sanitary thin paper.

5. 2. The package according to claim 1, wherein the rolled sanitary tissue paper is any one of a toilet paper roll, a kitchen paper roll, and a hand towel roll.

6. 6. The package of claim 5, wherein the rolls of sanitary thin paper have approximately the same dimensions, the width of the rolls of sanitary thin paper being 100 mm or more and 260 mm or less, and the radius R of the rolls of sanitary thin paper being 50 mm or more and 70 mm or less.

7. The packaging body according to any one of claims 1 to 5, wherein the packaging base material has a heat seal layer.

8. The packaging body according to any one of claims 1 to 5, wherein the ratio of the basis weight of the paper substrate to the basis weight of the packaging substrate is greater than 50% and is not greater than 100%.

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