Hygienic paper roll package

Abstract

The present invention provides a sanitary paper roll packaging body which is excellent in re-packaging property and in which a plurality of sanitary paper rolls are packaged with a paper-based packaging substrate, the sanitary paper roll packaging body being a sanitary paper roll packaging body in which a plurality of sanitary paper rolls are packaged with a packaging substrate, wherein the packaging substrate has a layer structure including a paper substrate and a sealing layer for sealing the packaging body, the thickness of the packaging substrate is 35 μm or more and 80 μm or less, the burst strength of the packaging substrate is 105 kPa or more and 190 kPa or less, and the geometric mean breaking elongation of the breaking elongation of the packaging substrate in the height direction parallel to the axial direction of the sanitary paper rolls packaged in the packaging body and the breaking elongation of the packaging substrate in the width direction perpendicular to the axial direction of the sanitary paper rolls packaged in the packaging body is 2.9% or more and 6.0% or less.

Description

TECHNICAL FIELD

[0001] The present application relates to a toilet paper roll package in which a plurality of toilet paper rolls are wrapped with a wrapping base material. BACKGROUND

[0002] Generally, toilet paper rolls such as kitchen paper rolls, toilet paper rolls, and the like are sold in a state in which a plurality of toilet paper rolls are wrapped with a wrapping base material. Such a package is desired to be rewrapped after opening and taking out a part of the wrapped package, so that the remaining toilet paper rolls can be stored neatly (Patent Literature 1). This requirement is particularly significant for kitchen paper rolls.

[0003] In recent years, the problem of plastic waste is becoming more serious worldwide, and in order to improve the earth's environment, it is desirable to replace the raw material of the wrapping from plastic to other raw materials. In the field of wrapping paper products, a wrapping package in which a paper product is wrapped with wrapping paper has also been proposed, in which the raw material of the wrapping is replaced from a plastic film to a material mainly composed of paper (Patent Literature 2).

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Laid-Open No. 2003-104449

[0007] Patent Literature 2: Japanese Patent Application Laid-Open No. 2021-172415 SUMMARY

[0008] Problems to be Solved by the Invention

[0009] However, if the wrapping base material is replaced from a plastic film to a base material mainly composed of paper, the paper is thicker than the film and is difficult to bend, and thus it is difficult to rewrap the remaining toilet paper rolls after taking out a part of the plurality of toilet paper rolls wrapped in the wrapping package with the wrapping base material, and the storage property is poor compared to the film.

[0010] Therefore, an object of the present application is to provide a toilet paper roll package in which toilet paper rolls are wrapped with a wrapping base material mainly composed of paper, which has good rewrapping property for the remaining toilet paper rolls after taking out a part of the plurality of toilet paper rolls wrapped in the wrapping package.

[0011] Method for Solving the Problem

[0012] To address the aforementioned issues, the inventors conducted in-depth research and discovered that the problems can be solved by using the following toilet paper roll packaging: a toilet paper roll packaging body that contains multiple toilet paper rolls packaged in a packaging substrate, wherein the packaging substrate has a layered structure including a paper substrate and a sealing layer for sealing the packaging body; the thickness of the packaging substrate is 35 μm or more and 80 μm or less; the bursting strength of the packaging substrate is 105 kPa or more and 190 kPa or less; and the geometric mean elongation at break of the packaging substrate in the height direction parallel to the axial direction of the toilet paper rolls contained within the packaging body and the elongation at break in the width direction perpendicular to the axial direction of the toilet paper rolls contained within the packaging body is 2.9% or more and 6.0% or less.

[0013] Specifically, the present invention has the following structure.

[0014] [1] A toilet paper roll packaging body, which is a toilet paper roll packaging body containing multiple toilet paper rolls packaged with a packaging substrate, characterized in that,

[0015] The packaging substrate has a layered structure, which includes a paper substrate and a sealing layer for sealing the package.

[0016] The thickness of the packaging substrate is 35μm or more and 80μm or less.

[0017] The bursting strength of the packaging substrate is above 105 kPa and below 190 kPa.

[0018] The geometric mean elongation at break of the packaging substrate in the height direction parallel to the axial direction of the toilet paper roll inside the packaging body and in the width direction perpendicular to the axial direction of the toilet paper roll inside the packaging body is 2.9% or more and 6.0% or less.

[0019] [2] The toilet paper roll packaging body according to [1] is characterized in that the air permeability of the packaging substrate is more than 1000 seconds.

[0020] [3] The toilet paper roll packaging body according to [1] or [2] is characterized in that the bending stiffness of the packaging substrate in the width direction is more than 8 μNm and less than 35 μNm.

[0021] [4] The toilet paper roll packaging body according to [1] or [2] is characterized in that the smoothness of the side of the packaging substrate that contacts the toilet paper roll inside the packaging body is 100 seconds or more.

[0022] [5] The toilet paper roll packaging body according to [1] or [2] is characterized in that the transparency of the packaging substrate is 60% or more.

[0023] [6] The toilet paper roll packaging body according to [1] or [2] is characterized in that the paper substrate is glassine paper.

[0024] [7] The toilet paper roll packaging body according to [1] or [2] is characterized in that the packaging body is in the form of candy packaging.

[0025] Effects of the Invention

[0026] According to the present invention, a toilet paper roll packaging body is provided that has good repackaging properties for the remaining toilet paper rolls after a portion of the multiple toilet paper rolls inside the packaging body is removed, and that the toilet paper rolls are packaged in a paper-based packaging substrate. Attached Figure Description

[0027] FIG. 1 This is a diagram illustrating a toilet paper roll packaging body according to an embodiment of the present invention.

[0028] FIG. 2 This is a diagram illustrating one embodiment of the packaging substrate according to an embodiment of the present invention.

[0029] FIG. 3 This is a diagram illustrating another embodiment of the packaging substrate according to an embodiment of the present invention.

[0030] FIG. 4 This diagram illustrates an example of the opening and repackaging process for toilet paper rolls.

[0031] FIG. 5 This is another example of the opening and repackaging process for toilet paper roll packaging. Detailed Implementation

[0032] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The embodiments and drawings described below are for illustrative purposes only and do not limit the present invention.

[0033] <First Implementation Method>

[0034] (Toilet paper roll packaging)

[0035] FIG. 1 This is a schematic perspective view of a toilet paper roll packaging body according to the first embodiment of the present invention. In the first embodiment of the present invention, the toilet paper roll packaging body (hereinafter also referred to as "packaging body") 1 includes a plurality of toilet paper rolls 2 and a packaging substrate 10 for packaging the plurality of toilet paper rolls 2.

[0036] (Toilet Paper Roll) In this instruction manual, "toilet paper roll" refers to a roll of toilet paper products made by winding long strips of toilet paper, kitchen paper, hand towels, etc., into a roll. Examples of toilet paper rolls may include, without limitation, toilet paper rolls, kitchen paper rolls, hand towel rolls, etc.

[0037] Toilet paper rolls can be single-layer products consisting of a single sheet of toilet paper rolled into a roll, or multi-layer products consisting of two or more sheets of toilet paper rolled into a roll in an overlapping manner. For toilet paper sheets, depending on the required quality, surface embossing, perforation for separation lines, and graphic or text printing can be applied to imbue them with patterns, logos, messages, and other information.

[0038] Toilet paper sheets are obtained by papermaking from pulp containing fibrous raw materials, i.e., pulp components. Examples of pulp components include wood pulp, non-wood pulp, and recycled pulp. To ensure consistent quality and operation, various chemicals such as paper strength enhancers and defoamers can be added as any ingredient. Papermaking can be performed using any known papermaking machine. During the papermaking process, the toilet paper sheets can undergo processes such as pleating. Calendering can be performed during the papermaking process or any subsequent process.

[0039] exist FIG. 1 In the example shown, toilet paper roll 2 is a kitchen paper roll. Packaging substrate 10 wraps two kitchen paper rolls 2 together.

[0040] In this invention, the number of toilet paper rolls 2 packaged in the packaging body 1 can be determined based on the ease of handling of the packaging body 1 and product sales strategy, which are caused by factors such as the size and weight of the toilet paper rolls 2 and the strength (fracture strength) of the packaging substrate 10. The number of toilet paper rolls 2 packaged in the packaging body 1 is preferably an even number, more preferably four, and even more preferably two.

[0041] (Packaging substrate) The packaging substrate 10 according to the embodiments of the present invention has a paper substrate 100 and a sealing layer 110 for sealing the package.

[0042] FIG. 2 and FIG. 3 They represent the components FIG. 1 The figure shows a non-limiting example of a possible arrangement of the packaging substrate 10 of the packaging body 1. FIG. 1 In the example shown, the packaging of package 1 adopts a so-called candy-style packaging form, such as individually wrapped soft candy like candy or boxed cigarette packaging.

[0043] FIG. 2(a) is a schematic unfolded view of the packaging substrate 10, which is a plan view of the packaging substrate 10 as viewed from the outer side (hereinafter also referred to as "surface") of the packaging body 1. FIG. 2 (b) is along FIG. 2 A schematic cross-sectional view of the packaging substrate 10 shown in (a) along line IIb-IIb, and FIG. 2 (c) is along FIG. 2 A schematic cross-sectional view of the packaging substrate 10 shown in (a) along line IIc-IIc.

[0044] Reference FIG. 2 In (a), the packaging substrate 10 in this example is a rectangular OPQR. The area indicated by the shaded line in the figure is filled with a sealant for encapsulating the package 1.

[0045] Reference FIG. 3 The cross-sectional views in (b) and (c) show a sealant applied to the paper substrate 100 to form a sealing layer 110, and the packaging substrate 10 has a layered structure including the paper substrate 100 and the sealing layer 110. In this example, the sealing layer 110 completely covers one side of the paper substrate 100. The thickness and dimensions of each layer are shown schematically in the figures and are not drawn to scale.

[0046] FIG. 1 It indicates composition FIG. 2 The packaging substrate 10 of the packaging body 1 shown can be used in a manner that is similar to... FIG. 3 The diagram shows examples of different approaches.

[0047] FIG. 2 (a) to (c) respectively correspond to FIG. 3 (a) to (c). That is, FIG. 3 (a) is a schematic unfolded view of the packaging substrate 10, which is a plan view of the packaging substrate 10 as viewed from the outer side (surface) of the packaging body 1. FIG. 3 (b) is along FIG. 3 A schematic cross-sectional view of the packaging substrate 10 shown in (a) along line IIIb-IIIb. FIG. 3 (c) is along FIG. 3 A schematic cross-sectional view of the packaging substrate 10 shown in (a) along line IIIc-IIIc.

[0048] FIG. 2 and FIG. 3 The difference lies in the area on the packaging substrate 10 where the sealing layer 110 is provided. FIG. 3In the illustrated configuration, the sealing layer 110 is provided, as shown by the shaded area in the figure, in the region at the side end of the packaging substrate 10 represented by rectangle OPP1O1, the region at the upper end of the packaging substrate 10 represented by rectangle OO2R2R, and the region at the lower end of the packaging substrate 10 represented by rectangle PP2Q2Q. Additionally, in the figure, the sealing layer 110 is not provided in the region represented by rectangle O3P3Q2R2.

[0049] Reference FIG. 1 The cross-sectional views in (b) and (c) show that the packaging substrate 10 has a layered structure comprising a paper substrate 100 and a sealing layer 110, the sealing layer 110 partially covering one side of the paper substrate 100. The thickness and dimensions of each layer are shown schematically in the figures and are not drawn to scale.

[0050] Comparison FIG. 2 The packaging body 1, in FIG. 3 and FIG. 2 In any of the embodiments shown, a portion of the area represented by rectangle OPP1O1 in the packaging substrate 10 coincides with a portion of the area represented by rectangle RQQ1R1 (side end) (area represented by symbol 12S in the figure), and is joined via a sealing layer 110 provided in the area represented by rectangle OPP1O1. Furthermore, portions of the areas represented by rectangles OO2R2R and PP2Q2Q (upper and lower ends) (areas represented by symbols 12T and 12B in the figure) are folded and joined via a sealing layer 110 provided in the areas represented by rectangles OO2R2R and PP2Q2Q. Therefore, the side and upper / lower ends of the packaging substrate 10 described above substantially contribute to the sealing of the packaging body 1.

[0051] In this specification, the portion of the packaging substrate 10 that substantially contributes to the encapsulation of the packaging body 1 as described above will be referred to as the "encapsulation portion of the packaging body" or the "joining portion of the packaging substrate" and will be indicated by the symbol 12 (12S, 12T, 12B). The portion other than this will be referred to as the "non-encapsulation portion of the packaging body" or the "non-joining portion of the packaging substrate" and will be indicated by the symbol N12.

[0052] In the packaging substrate 10 according to the embodiments of the present invention, the area where the sealing layer 110 is formed is not limited to... FIG. 3 and FIG. 1 As shown in the example, as long as the packaging part 12 is included, it can be formed in any area on the paper substrate 100.

[0053] (Paper substrate)

[0054] In embodiments of the present invention, the paper substrate 100 of the packaging substrate 10, which serves as the packaging body 1, can be any type of paper substrate.

[0055] Paper substrate 100 can be manufactured using pulp components such as wood pulp, non-wood pulp, and deinked pulp as the main raw materials, and by papermaking using a papermaking machine through known methods.

[0056] Pulp components can be used alone or in mixtures of two or more. Because these pulp components have a significant impact on the quality of the paper substrate, they should be appropriately blended according to the required quality and specified types and mixing ratios.

[0057] For example, softwood kraft pulp (NKP) and / or hardwood kraft pulp (LKP) can be used in a preferred mixing ratio (mass%) of 0-60:100-40, more preferably 20-60:80-40, and even more preferably 40-60:60-40.

[0058] Softwood kraft pulp typically has longer fibers than hardwood kraft pulp. Therefore, if the proportion of softwood kraft pulp in the pulp raw material is increased, the resulting paper substrate 100 generally has increased paper strength. For example, the tensile strength in the MD direction (also known as the papermaking direction or longitudinal direction (T direction)) is increased, resulting in a paper substrate 100 that is not easily broken even when a force is applied in the MD direction.

[0059] The paper substrate 100 applicable to the packaging substrate 10 of the packaging body 1 can also be determined based on the processing suitability (bending ease, rigidity, printability) when manufacturing the packaging body 1, the strength (fractureability) and appearance (transparency, whiteness) when the packaging body 1 is made, and the repackaging properties of the packaging body 1 after opening.

[0060] In the paper substrate 100, various commonly used chemicals may be added as optional components to ensure the required quality and stability of the manufacturing process. Examples of optional components include dry strength agents, wet strength agents, sizing agents, bulking agents, dyes, fragrances, dispersants, water-retaining agents, resin control agents, and yield enhancers.

[0061] Specific examples of paper substrates 100 applicable to embodiments of the present invention include transparent paper such as cellophane or single-sided glossy paper such as pure white paper, but are not limited to these.

[0062] (cellophane)

[0063] Cellophane is a thin sheet of paper made by beating chemical pulp to a high concentration and then forming it. The resulting paper is passed through a calender, where heat and pressure are applied to break down the gaps between the fibers. Cellophane is characterized by its high smoothness, gloss, high density, high air permeability (i.e., a certain amount of air takes a long time to pass through a certain area of ​​the paper under a certain pressure; in other words, it has low air permeability) and semi-transparency.

[0064] Generally, "transparent" means that you can see through an object to its other side or interior. "Semi-transparent" means: low transparency; between transparent and opaque; the shape of an object opposite it is not clearly visible, but its color and brightness are visible; or a similar state. "Opaque" means that you cannot see objects on the opposite side through it. In this specification, "transparent" and "semi-transparent" will be used collectively and simply referred to as "transparent".

[0065] "Transparency" refers to the percentage of light that passes through paper, expressed as a percentage of incident light. The higher the transparency value, the more clearly objects on the opposite side or inside are visible.

[0066] As a preferred embodiment of the present invention, FIG. 1 In the example, the paper substrate 100 of the packaging substrate 10 uses cellophane, and the toilet paper roll 2 (two kitchen paper rolls) that are packaged as the packaging body 1 can be seen through the packaging substrate 10.

[0067] From the viewpoint of visibility of the exterior of the packaging body 1 of the packaged object, i.e., the toilet paper roll 2, in a preferred embodiment of the present invention, the transparency of the packaging substrate 10 is 60% or more, preferably 65% ​​or more, more preferably 70% or more, and even more preferably 75% or more. If the transparency of the packaging substrate 10 is 60% or more, it is easy to confirm the state of the packaged object 2 inside the packaging body 1 (e.g., the type, quantity, color or pattern, and shape of the packaged object 2 (whether it is printed or embossed, etc.)).

[0068] As a means of achieving such transparency in the packaging substrate 10, a method of using a highly transparent paper substrate 100 can be cited. In a preferred embodiment of the present invention, the transparency of the paper substrate 100 is 60% or more, preferably 65% ​​or more, more preferably 70% or more, and even more preferably 75% or more. Examples of highly transparent papers suitable for the paper substrate 100 include cellophane and parchment, but are not limited to these.

[0069] The transparency of the paper substrate 100 and the packaging substrate 10 can be measured according to ISO 5-2 using a diffuse light transmittance meter DOT-5 (manufactured by Murakami Color Technology Research Institute Co., Ltd.). It should be noted that the transparency of the packaging substrate 10 is measured in the non-jointed area (non-sealed area of ​​the packaging body 1) N12 of the packaging substrate 10.

[0070] (The effect of using cellophane)

[0071] By using cellophane as the paper substrate 100 of the packaging substrate 10 in this embodiment, the following effects can be achieved, for example.

[0072] (1) Since the cellophane is transparent, the toilet paper roll 2 inside the packaging 1 can be easily seen and identified in the non-sealed area N12 of the packaging 1 through the transparent cellophane 100 (and the transparent sealing layer 110 provided thereon when the cellophane 100 is present) (having internal visibility). For example, the type, quantity, color or pattern, shape (e.g., whether it is printed or embossed) of the toilet paper roll 2 can be confirmed from the outside of the packaging 1 (see reference). FIG. 1 ).

[0073] (2) Because cellophane has high air permeability, the packaged body, namely toilet paper roll 2, wrapped by the packaging substrate 10 is not easily affected by external moisture or external odors.

[0074] (parchment)

[0075] Parchment is a transparent paper in which some of the cellulose fibers in the base paper are transformed into amorphous amyloid protein. It can be obtained by treating base paper, which is mainly composed of cellulose fibers, with acids such as sulfuric acid, hydrochloric acid, formic acid, and acetic acid. For example, parchment can be made by immersing the base paper in sulfuric acid, repeatedly neutralizing and / or washing with water, and then drying it. The immersion time cannot be generalized and can be appropriately adjusted by considering factors such as the thickness, density, sizing degree, washing ability, and drying ability of the base paper.

[0076] By impregnating a base paper made of cellulose pulp fibers in sulfuric acid, the cellulose swells, hydrolyzes, and dissolves. The dissolved cellulose becomes a viscous, semi-transparent gel-like substance that covers the surface of the base paper, firmly binding the fibers together and filling the pores and voids in the paper layers, forming a very dense paper structure. As a result, diffuse reflection of light within the paper layers is reduced, promoting transparency.

[0077] The gelatinous substance formed by the hydrolysis of cellulose is neutralized and / or washed to stop the hydrolysis reaction, becoming hydrated cellulose. Therefore, the pores in the paper are blocked by cellulose, which is chemically identical to the base paper, thus improving transparency and reducing minor white spot unevenness inferred from the texture or pores in the base paper layers. The result is a spotless base paper with uniform transparency.

[0078] By using pulp containing fine fibrous cellulose with an average fiber width of 2nm to 50nm obtained through chemical treatment or defibrillation of lignocellulose raw materials, it is possible to produce paper with higher transparency.

[0079] (The effects of using parchment)

[0080] By using parchment paper as the paper substrate 100 for the packaging substrate 10, the internal visibility effect can be achieved in the same way as when cellophane is used. That is, from the outside of the packaging body 1, the toilet paper roll 2 packaged inside the packaging body 1 can be easily seen and identified through the transparent parchment paper 100 of the non-sealed part of the packaging body 1 (and the transparent sealing layer 110 provided thereon when the parchment paper 100 is present). For example, the type, quantity, color or pattern, shape (e.g., whether it has embossing) of the toilet paper roll 2 can be confirmed from the outside of the packaging body 1 (see reference). FIG. 1 ).

[0081] (Single-sided glossy paper)

[0082] In one embodiment of this invention, the paper substrate 100 may be single-sided glossy paper. Single-sided glossy paper refers to paper that improves the smoothness and gloss of one side, having a relatively smooth and smooth glossy side (high smoothness side) and a relatively low smoothness and rougher touch non-glossy side (low smoothness side).

[0083] In papermaking from pulp raw materials, papermaking takes place in a paper machine with mirror-finished Yankee dryers. Wet paper is pressed onto the surface of the mirror-finished Yankee dryers and dried, thereby producing single-sided glossy paper. The smoothness and gloss of the surface in contact with the Yankee dryers are higher than those of the surface not in contact with the Yankee dryers, thus enabling the production of paper substrates with both glossy and non-glossy surfaces (single-sided glossy paper) 100.

[0084] For example, cellophane is produced by passing the base paper, made from high-consistency chemical pulp, through a calender under heat and pressure to break down the gaps between the fibers. This results in high density and smoothness. In this case, for single-sided glossy paper, the smoothness of the surface in contact with the Yankee dryer is improved by pressing the wet paper onto the surface of a mirror-finished Yankee dryer. Since single-sided glossy paper does not undergo calendering or its conditions are stable, the interfiber bonds of the pulp fibers in the base paper are relatively less likely to be broken, thus allowing for the relatively inexpensive production of paper with strength comparable to cellophane.

[0085] (Pure white paper)

[0086] In one embodiment of the present invention, the paper substrate 100 may be pure white paper. Pure white paper is a type of single-sided glossy paper described above, manufactured using pulp with high whiteness, such as bleached pulp, and has high whiteness.

[0087] (Whiteness)

[0088] The whiteness of pure white paper is, for example, 80% or more, or, for example, 90% or more. Whiteness can be measured according to JISP8148:2005 (ISO2470).

[0089] (The effect of using pure white paper)

[0090] In the case of using pure white paper for the paper substrate 100, in addition to the effects described in the section on single-sided glossy paper, it has a high-quality appearance due to its high whiteness. Furthermore, when printing on the packaging substrate 10, it can improve the visibility of the print by making the background white.

[0091] (Sealing layer)

[0092] Sealing layer 110 is a layer containing sealant.

[0093] (Sealant)

[0094] As a sealant applicable to embodiments of the present invention, any sealant known in the art that can bond with the packaging substrate 10 to seal the packaging body 1 can be used. The sealant can be any material exhibiting heat-sealing properties, i.e., a heat sealant, or any material exhibiting adhesive properties other than a heat sealant, i.e., an adhesive.

[0095] As heat-sealing agents, polyolefin resins and other thermoplastic resins can be used, with polyethylene resins being preferred. Examples of such materials include low-density polyethylene, linear low-density polyethylene, high-density polyethylene, ethylene-α-olefin copolymers, ethylene-vinyl acetate copolymers, ethylene-acrylic acid copolymers, ethylene-ethyl acrylate copolymers, ethylene-methyl acrylate copolymers, ethylene-methacrylic acid copolymers, ionomers, amorphous polyesters, polypropylene, styrene-acrylic acid copolymers, propylene-ethylene copolymers (preferably copolymers with an ethylene content of 10 mol% or less), or polypropylene resins grafted or copolymerized with unsaturated carboxylic acids, unsaturated carboxylic anhydrides, ester monomers, etc., medium-density polyethylene, and high-density polyethylene. Any one of these materials can be used alone, or two or more can be used in combination.

[0096] As adhesives, examples include, in addition to water-soluble polymers such as methylcellulose, hydroxypropyl methylcellulose, hydroxyethyl methylcellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose, polyvinylpyrrolidone, polyvinyl alcohol, etc., their derivatives and mixtures thereof.

[0097] (Method for forming the sealing layer)

[0098] The sealing layer 110 can be formed, for example, by a commonly used method as listed below.

[0099] (1) A method for forming a film on a paper substrate 100 by extrusion of a thermoplastic resin such as a polyolefin resin or a composition containing a thermoplastic resin.

[0100] (2) A method of attaching a film formed of thermoplastic resin or a film containing thermoplastic resin onto a paper substrate 100 using a known heat-sealing processing apparatus (lamination processing apparatus).

[0101] (3) A method of applying an aqueous heat sealant containing a thermoplastic resin or a thermoplastic resin composition dissolved or dispersed in water, or a solvent-based heat sealant containing a thermoplastic resin or a thermoplastic resin composition dissolved or dispersed in a solvent, a water-soluble polymer, its derivatives or mixtures thereof, onto a paper substrate 100 by known methods such as roll coating, gravure roll coating, or touch coating.

[0102] As described above, by forming a sealing layer 110 on the paper substrate 100, the packaging substrate 10 according to the embodiments of the present invention can be obtained.

[0103] (Examples of packaging manufacturing methods)

[0104] Reference FIG. 2 and FIG. 2 Non-limiting examples of packaging forms and manufacturing methods applicable to the packaging body 1 of the first embodiment will be described. It should be noted that, in substitution... FIG. 3 The packaging substrate 10 shown is used FIG. 1 In the case of the packaging substrate 10 shown, the packaging body 1 can also be manufactured by the same method.

[0105] FIG. 2 The package 1 shown is a so-called candy-style package, which can be manufactured, for example, through the process shown below.

[0106] (Step 1) Preparation as follows FIG. 2 The process of the rectangular OPQR packaging substrate 10 shown includes applying a sealant for sealing the packaging body 1 to a designated area of ​​the packaging substrate 10 (the area indicated by the shaded line in the figure), thereby forming a sealing layer 110.

[0107] exist FIG. 2In the example, the MD direction (longitudinal direction) of the packaging substrate 10 and, consequently, the MD direction (longitudinal direction) of the paper substrate 100 are consistent with direction A in the figure. However, in this embodiment, the direction of the packaging substrate 10 (paper substrate 100) is not limited to this. The direction of the packaging substrate 10 (paper substrate 100) can be determined based on the orientation caused by the fiber orientation of the paper, from the perspectives of processability during the manufacture of the packaging body 1 and repackaging after opening (flexibility, strength relative to bending), posture and strength (fractureability) when the packaging body 1 is made, or other desired characteristics.

[0108] (Step 2) The process of arranging the toilet paper rolls (two kitchen paper rolls) 2, which are the packaging bodies, so that they face the back of the packaging substrate 10 (the inner side of the packaging body 1) and the axial direction of the rolls is aligned with the direction A shown by arrow A in the figure.

[0109] (Step 3) The packaging body 2 is rolled up with the packaging substrate 10 with the surface of the packaging substrate 10 (which becomes the outer side of the packaging body 1) as the outside, so that the two ends of the packaging substrate 10 (the area of ​​the side end of the packaging substrate 10 shown by rectangle OPP1O1 and the area of ​​the side end of the packaging substrate 10 shown by rectangle RQQ1R1) 12S overlap, and the packaging is packaged into a cylindrical shape.

[0110] Through this process 3, the two ends 12S of the packaging substrate 10 are sealed by the sealing layer 110 provided on the surface of the paper substrate 100, with the surface and back of the paper substrate 100 joined together.

[0111] Hereinafter, in this specification, the joining method in which the different sides (front and back) of the paper substrate 100 are joined and bonded together will also be referred to as "overlay".

[0112] (Step 4) Next, at both ends (top and bottom) of the opening of the cylindrical package formed in step 3.

[0113] Each of 12T and 12B involves folding the portion of the packaging substrate 10 exposed from the periphery of the toilet paper roll 2 into two pairs of opposing wing portions, joining them along the end face of the toilet paper roll 2, and sealing the toilet paper roll 2.

[0114] FIG. 1 In (a), the upper end region 12T of the packaging substrate 10 shown by rectangle OO2R2R and the lower end region 12B of the packaging substrate 10 shown by rectangle P2PQQ2 are folded according to the convex fold line UFL (dashed line) and concave fold line DFL (dashed dotted line) in the figure to form a wing-shaped portion. The wing-shaped portion is joined by the sealing layer 110 provided on the surface of the paper substrate 100, thereby obtaining FIG. 2Package 1 in the state shown.

[0115] Thus, at the upper and lower ends 12T and 12B of the packaging substrate 10, the packaging is sealed by joining the surfaces of the paper substrate 100 together via their respective sealing layers 110. Hereinafter, in this specification, the joining method in which the same surfaces of the paper substrate 100 are joined together will also be referred to as "butt bonding".

[0116] It should be noted that, in this specification, the "upper and lower ends" of the packaging substrate 10 and the "upper and lower ends" of the packaging body 1 refer to the two ends in the direction A indicated by arrow A in the figure, and the "(two) side ends" of the packaging substrate 10 refer to... FIG. 4 The two ends of the packaging substrate 10 are wound in the direction of arrow B, which intersects with direction A. In this specification, direction A, indicated by arrow A, is also referred to as the "height direction," and direction B, indicated by arrow B, is also referred to as the "width direction."

[0117] Through the above processes, in this embodiment that adopts a candy packaging form, a sealing layer 110 is provided on the outer surface of the packaging body 1, and two types of packaging are performed: overlapping packaging and butt-fitting packaging. As a result, the packaging body 1 is sealed by the sealing part 12, which has a sealing part 12S in which the two ends of the packaging substrate 10 are overlapped and joined by abutting the surface and back of the paper substrate 100, and sealing parts 12T and 12B in which the upper and lower ends of the packaging substrate 10 are folded and joined by abutting the surfaces of each other.

[0118] It should be noted that in the manufacturing process illustrated above, a packaging substrate 10 is prepared in advance and cut into rectangles of a specified size from a top view to manufacture a packaging body 1. However, the manufacturing method of the packaging body 1 is not limited to this. For example, the packaging substrate 10 can also be prepared in the form of a long, continuous sheet. In a subsequent process, the packaging substrate 10 can be cut while or after the toilet paper roll 2 is arranged relative to the packaging substrate 10 to manufacture the packaging body 1.

[0119] In embodiments of the present invention, the ends of the packaging substrates 10 that overlap at the encapsulation portions 12 (12S, 12T, 12B) are joined together by a sealant contained in the sealing layer 110 of the packaging substrates 10. When the sealant is a heat sealant, the joining is performed by heat sealing (heat fusion); when the sealant is an adhesive, the joining is performed by adhesive bonding.

[0120] When the sealant is a heat-sealing agent, the heat-sealing process of the heat-sealing layer 110 can be performed using a known heat-sealing machine. During the heat-sealing process, heat and pressure are applied to the areas of the encapsulation portions 12 (12S, 12T, 12B) that overlap with the packaging substrate 10, causing the heat-sealing agent of the heat-sealing layer 110 in these areas to soften and melt. This results in phenomena such as micro-embedding of the softened heat-sealing agent and the mixing and integration of the molten heat-sealing agent. After cooling, the encapsulation portions 12 (12S, 12T, 12B) with the heat-sealing layer 110 firmly bonded are obtained.

[0121] When the sealant is an adhesive, the adhesive needs a certain amount of time to dry, while when the sealant is a heat sealant, there is no need to consider the drying time, which is preferable.

[0122] [Opening and Repackaging / Repackaging]

[0123] Reference FIG. 5 and FIG. 4 The opening and repackaging operations of package 1, as well as the repackaging process, are explained.

[0124] (Opening and repackaging)

[0125] FIG. 4 This is a schematic diagram illustrating an example of the opening and repackaging operation of package 1.

[0126] FIG. 4 (1) indicates the packaging body 1 before opening.

[0127] FIG. 4 (2) represents an example of the opening operation of the packaging body 1. In this example, the opening of the packaging body 1 is performed by peeling off the joint of the packaging substrate 10 at the sealing part 12 of the packaging body 1.

[0128] First, in order to fully remove the toilet paper roll 2, the sealing layer 110 is peeled off from the packaging substrate 10 at the sealing part (joint part of the packaging substrate 10) 12 of the packaging body 1. At this time, the joints of the upper end, side end, and lower end 12 (12T, 12S, 12B) of the packaging substrate 10 can be peeled off entirely or partially.

[0129] Next, remove one of the multiple toilet paper rolls 2 (in this example, one of two kitchen paper rolls) from the packaging 1.

[0130] FIG. 4 (3) represents an example of package 1 after repackaging.

[0131] First, rewind the remaining toilet paper roll 2 using packaging substrate 10, so that... FIG. 4In step (2), the internal space of the packaging body 1 created by removing the toilet paper roll 2 disappears. Next, the upper and lower ends 12 (12T, 12B) of the packaging substrate 10 are folded along the end face of the toilet paper roll 2 to close the opening of the packaging body 1. In this way, the packaged object (toilet paper roll) 2 is repackaged. In order to ensure good storage of the toilet paper roll 2, it is repackaged in such a way that the toilet paper roll 2 inside is not exposed from the packaging body 1 after repackaging with the packaging substrate 10. In this way, the following is obtained: FIG. 5 The repackaged packaging shown in (3) is 1.

[0132] FIG. 5 This is a schematic diagram illustrating another example of the opening and repackaging operation of package 1.

[0133] exist FIG. 5 In the example, FIG. 5 (1) indicates the packaging body 1 before opening. FIG. 5 (2) represents an example of the opening operation of package 1. FIG. 5 (3) represents an example of repackaging of package 1.

[0134] exist FIG. 5 In the example, such as FIG. 4 As shown in (2), the opening of the packaging body 1 is mainly carried out by tearing open the packaging substrate 10 at the non-sealed part N12 of the packaging body 1, which is consistent with... FIG. 5 The examples are different. FIG. 4 The repackaging operation of the example and FIG. 1 The examples are presented in roughly the same manner, so repeated explanations are omitted.

[0135] Thus, in embodiments of the present invention, the opening of the packaging body 1 can be performed by peeling off the joint of the sealing part 12, or by breaking the packaging substrate 10 mainly in the area of ​​the non-sealing part N12, or by combining peeling off the joint of the sealing part 12 and breaking the packaging substrate 10 mainly in the area of ​​the non-sealing part N12.

[0136] In any case, for good storage, it is preferable to repackage the toilet paper roll 2 in a manner that prevents the toilet paper roll 2 inside from being exposed from the package 1 after repackaging with the packaging substrate 10.

[0137] (Repackaging)

[0138] The paper-based packaging substrate 10 is typically thicker and less flexible than conventional films used as packaging substrates. Therefore, during repackaging, there is a tendency to repackage the packaging substrate 10 in a manner that allows the remaining toilet paper rolls 2 to remain uncovered after removing a portion of the multiple toilet paper rolls 2 contained within the packaging 1.

[0139] Furthermore, even if the remaining toilet paper roll 2 can be temporarily repackaged using the paper-based packaging substrate 10 without exposure, the packaging 1 may sometimes open naturally over time after repackaging, causing the packaged item 2 to be exposed. If exposure occurs, the shelf life deteriorates.

[0140] To address this issue, the present invention aims to provide a toilet paper roll packaging body that allows for good repackaging of the remaining toilet paper rolls after a portion of the multiple toilet paper rolls inside the packaging body is removed, wherein the toilet paper rolls are packaged in a packaging substrate primarily composed of paper.

[0141] In this specification, the term "repackaging capability" refers to the ease with which the packaged item 2 can be repackaged using the packaging substrate 10 after the package 1 has been opened. The ease of repackaging includes the flexibility (processability) of the packaging substrate 10 and the difficulty of opening the repackaged item over time.

[0142] In order to solve the above-mentioned problems, in-depth research was conducted. As a result, the inventors found that if the thickness of the packaging substrate 10 is simply reduced in order to improve repackaging performance, the basis weight of the packaging substrate 10 will also decrease. As the basis weight decreases, the packaging substrate 10 is prone to breakage. Furthermore, it was found that by controlling the thickness of the packaging substrate 10, the burst strength of the packaging substrate 10, and the geometric mean elongation at break of the packaging substrate 10 within a specified range, the above-mentioned problems can be solved.

[0143] (weight)

[0144] In this specification, the basis weight of the packaging substrate 10 and the basis weight of the paper substrate 100 are the basis weights (g / m²) of each sheet measured according to JIS P8124. 2 Additionally, the basis weight of the sealing layer 110 can be determined by subtracting the basis weight of the paper substrate 100 from the basis weight of the packaging substrate 10 in the area where the sealing layer 110 is provided. The basis weight of the packaging substrate 10 is measured at the non-sealed portion (non-jointed portion of the packaging substrate 10) N12 of the packaging body 1.

[0145] (Gram weight of packaging substrate)

[0146] In embodiments of the present invention, the basis weight of the packaging substrate 10 is preferably, for example, 39 g / m³. 2 Above and 65g / m 2 The following is more preferably 45g / m 2 Above and 60g / m 2 the following.

[0147] When the basis weight of the packaging substrate 10 is low, the basis weight of the paper substrate 100 contained within it is also typically low, with fewer pulp fibers and less inter-fiber bonding, resulting in lower strength and a greater susceptibility to breakage. Therefore, from the perspective of minimizing breakage, a higher basis weight is preferable for the packaging substrate 10.

[0148] On the other hand, when the basis weight of the packaging substrate 10 is high, the paper thickness or density usually increases, and the softness and flexibility of the packaging substrate 10 decrease. During the manufacturing and repackaging of the packaging body 1, the packaging substrate 10 is difficult to bend, and there is a tendency for the processing suitability and repackaging performance of the packaging body 1 to decrease.

[0149] Furthermore, due to the increased paper thickness, when the sealing layer is a heat-sealing layer, heat transfer becomes insufficient during the heat-sealing process, and sometimes the heating temperature of the heat-sealing layer decreases, resulting in poor bonding strength. Therefore, from the perspectives of the processability and repackaging properties of the packaging body 1, and the heat-sealing properties (adhesion) at the sealing portion 12 of the packaging body 1, the basis weight of the packaging substrate 10 is preferably lower.

[0150] If the weight of the packaging substrate 10 is within the above range, the packaging substrate 10 has moderate strength and is not easily broken, and can ensure the processability of the packaging body 1 during manufacturing and the heat sealability of the sealing part 12.

[0151] (Weight of the sealing layer)

[0152] In an embodiment of the present invention, the basis weight of the sealing layer 110 is preferably 5 g / m³. 2 Above and 25g / m 2 In the case of a sealing layer obtained by extruding a thermoplastic resin or a composition containing a thermoplastic resin onto a paper substrate, and a sealing layer obtained by attaching a film formed of thermoplastic resin or a film containing a thermoplastic resin using a lamination processing apparatus, the basis weight of the sealing layer 110 is more preferably 10 g / m². 2 Above and 20g / m 2 The following applies. Furthermore, when a heat-sealing agent or adhesive is applied to a paper substrate, the basis weight of the sealing layer 110 is more preferably 5 g / m². 2 Above and 10g / m 2 the following.

[0153] When the weight of the sealing layer 110 is low, the thickness (amount) of the sealing layer (adhesive or heat sealant) that can participate in the bonding between the bonded packaging substrates 10 is usually thinner (less), and good adhesion (encapsulation) can sometimes not be obtained in the encapsulation portion 12.

[0154] Furthermore, if the basis weight of the sealing layer 110 increases, the sealing layer 110 typically becomes thicker. In the case where the sealing layer 110 is a heat-sealing layer, if the sealing layer 110 becomes thicker, heat transfer may become insufficient during the heat-sealing process. In this case, it is difficult to achieve the anchoring effect resulting from the melting, fusion, and penetration of the heat sealant into the recess, leading to poor bonding strength and poor sealing performance.

[0155] If the weight of the sealing layer 110 is within the above range, the adhesiveness and heat-sealing properties of the encapsulation part 12 can be guaranteed.

[0156] (Thickness of packaging substrate (paper thickness))

[0157] In embodiments of the present invention, the thickness (paper thickness) 10th of the packaging substrate 10 is 35 μm or more and 80 μm or less, preferably 40 μm or more and 75 μm or less, and more preferably 45 μm or more and 65 μm or less.

[0158] The thickness (paper thickness) of the packaging substrate can be measured according to ISO 534:2011. The pressure on the pressure surface during the measurement is 100 kPa ± 10 kPa. During the measurement, the area of ​​the non-sealed part N12 is measured, avoiding the sealing part 12 of the packaging body 1.

[0159] As mentioned above, refer to FIG. 2 and FIG. 3 , FIG. 1 The packaging substrate 10 has a sealing portion (joining portion of the packaging substrate 10) 12 (12S, 12T, 12B) of the packaging body 1 and the other area, namely the non-sealing portion (non-joining portion of the packaging substrate 10) N12 of the packaging body 1. The sealing portion is the area where the ends of the packaging substrate 10 overlap and are joined by a sealing layer 110 at the ends, thereby sealing the packaging body 1.

[0160] The thickness 10th of the packaging substrate 10 is the thickness measured at N12 of the non-sealed portion (non-jointing portion of the packaging substrate 10) of the packaging body 1. FIG. 2 In the package 1 shown, the thickness of the packaging substrate 10, which is wound circumferentially along the toilet paper roll 2 (in the direction B perpendicular to direction A as indicated by arrow A as the axial direction) and forms the side of the package 1, is measured in the area that does not contribute to the sealing of the package 1. This measurement area corresponds to the area where... FIG. 3 and FIG. 2 The area represented by rectangle O3P3Q3R3 in the schematic unfolded diagram of the packaging substrate 10.

[0161] At this time, in such FIG. 3In the structure shown, where the sealing layer 110 is disposed on the entire surface of the packaging substrate 10 such that the non-sealed portion (non-bonded portion) N12 includes the sealing layer 110, the thickness 10th of the packaging substrate 10 is the thickness including the paper substrate 100 and the sealing layer 110. Furthermore, in... FIG. 1 In the structure shown, the sealing layer 110 is provided in the encapsulation part (joint part of the packaging substrate 10) 12 of the packaging body 1, but the non-encapsulation part (non-joint part of the packaging substrate 10) N12 of the packaging body 1 does not include the sealing layer 110. The thickness 10th of the packaging substrate 10 becomes the thickness including the paper substrate 100 but excluding the sealing layer 110.

[0162] In this embodiment, the physical properties of the packaging substrate 10, such as thickness, burst strength, elongation at break, air permeability, flexural stiffness, smoothness, and transparency, are measured at the non-sealed portion (non-jointed portion of the packaging substrate 10) N12 of the packaging body 1. Furthermore, the physical properties of the packaging substrate 10 are measured under the same conditioning conditions as the sample conditioning conditions, according to JIS P8111 conditioning samples.

[0163] If the thickness 10th of the packaging substrate 10 is thinner, the basis weight of the packaging substrate 10 also tends to be smaller. As the basis weight decreases, the packaging substrate 10 becomes more prone to breakage.

[0164] If the thickness 10th of the packaging substrate 10 is relatively thick, when a portion of the multiple toilet paper rolls 2 inside the packaging body 1 is removed and the remaining toilet paper rolls 2 are repackaged with the packaging substrate 10, the packaging substrate 10 is difficult to bend. In addition, the packaging body 1 is prone to natural opening over time after repackaging, resulting in poor repackaging performance.

[0165] If the thickness of the packaging substrate 10 is above 35μm and below 80μm, the packaging substrate 10 is not easy to break and is easy to bend. After repackaging, the packaging body 1 is not easy to open naturally over time, and the repackaging performance becomes good.

[0166] (Density of packaging substrate)

[0167] In an embodiment of the present invention, the density of the packaging substrate 10 is preferably 0.850 g / cm³. 3 Above and 1.200 g / cm 3 The following is more preferably 0.900 g / cm³. 3 Above and 1.150 g / cm 3 the following.

[0168] The density of the packaging substrate is a calculated value obtained by measuring the basis weight and thickness (paper thickness) of the packaging substrate using the above-mentioned measurement method. It can be calculated using the formula: "(Basis weight of packaging substrate) ÷ (Thickness (paper thickness))" (unit: g / cm³). 3).

[0169] If the density of the packaging substrate 10 is less than 0.850 g / cm³ within the weight range specified in the above embodiments of the present invention, then... 3 If the fiber content is low, there will be less inter-fiber bonding, making the packaging substrate 10 prone to breakage. Furthermore, if the density of the packaging substrate 10 is greater than 1.200 g / cm³ within the weight range specified in the embodiments of the present invention described above, then... 3 If the packaging substrate 10 is difficult to bend, the processing suitability of the packaging body 1 during manufacturing and its repackaging performance after opening will be poor.

[0170] (Burning strength of packaging substrate)

[0171] In embodiments of the present invention, the burst strength of the packaging substrate 10 is 105 kPa or more and 190 kPa or less, preferably 105 kPa or more and 175 kPa or less, and more preferably 110 kPa or more and 170 kPa or less. As described above, the burst strength of the packaging substrate 10 is measured at the non-sealed portion (non-jointed portion of the packaging substrate 10) N12 of the packaging body 1.

[0172] The bursting strength of the packaging substrate 10 can be determined according to JIS P8112:2008.

[0173] If the burst strength of the packaging substrate 10 is low, the packaging substrate 10 is easily broken by the pressure applied by the fingertips when the package body 1 is pinched. If the burst strength of the packaging substrate 10 is high, the packaging substrate 10 is difficult to bend, and the package body 1 is easy to open naturally over time after repackaging, resulting in poor repackaging performance.

[0174] If the bursting strength of the packaging substrate 10 is above 105 kPa and below 190 kPa, the packaging substrate 10 is not easy to break when the packaging body 1 is pinched, and it is easy to bend. After repackaging, the packaging body 1 is not easy to open naturally over time, and the repackaging performance becomes good.

[0175] The burst strength of the packaging substrate can be adjusted by changing any one or a combination of two or more of the following conditions: (1) adjusting the ratio of softwood pulp to hardwood pulp during papermaking of the paper substrate 100, (2) adjusting the beating degree, (3) adjusting the J / W ratio, (4) selecting / changing the type / amount of dry strength agent, and (5) the type of sealant used for the sealing layer and (6) the basis weight of the sealing layer during the manufacturing of the packaging substrate 10. Here, the J / W ratio refers to the ratio of the ejection speed (J) of the pulp dispersion in the papermaking machine to the wire speed (W) during the papermaking of the paper substrate, also known as the ejection wire ratio.

[0176] (Geometric mean elongation at break of packaging substrate)

[0177] In embodiments of the present invention, the geometric mean elongation at break (GE) of the packaging substrate 10 is 2.9% or more and 6.0% or less, more preferably 3.0% or more and 5.5% or less, and even more preferably 3.0% or more and 5.0% or less.

[0178] If the geometric mean elongation at break of the packaging substrate 10 is small, it is easy to break at or near the point where pressure is applied by the fingers when the package body 1 is pinched. If the geometric mean elongation at break of the packaging substrate 10 is large, it will be difficult to open because the packaging substrate 10 will move due to stretching when the package body 1 is opened, thus damaging the packaging substrate 10. If the geometric mean elongation at break of the packaging substrate 10 is 2.9% or more and 6.0% or less, it is not easy to break when the package body 1 is pinched, and the package body 1 is easy to open.

[0179] The geometric mean elongation at break (GE) of the packaging substrate 10 is the axial elongation of the packaging substrate 10 relative to the toilet paper roll 2 contained within the packaging body 1 (in the axial direction). FIG. 2 , 2 In the diagram, the elongation at break ET is measured in the height direction (indicated by arrow A), parallel to the direction of A, and in the width direction (indicated by arrow A) of the packaging substrate 10, perpendicular to the axial direction of the toilet paper roll 2 contained within the packaging body 1. FIG. 1 to FIG. 3 In the figure, the geometric mean of the elongation at break (EH) in the direction of arrow B (indicated by arrow B) can be calculated by the following formula (I).

[0180] GE = (ET × EH) 1 / 2 ···(I)

[0181] The elongation at break ET in the height direction and the elongation at break EH in the width direction of the packaging substrate 10 were measured at the non-sealed portion (joint portion of the packaging substrate 10) N12 of the packaging body 1.

[0182] When determining the tensile strength of the packaging substrate 10 in the height direction (A direction) and the tensile strength of the packaging substrate 10 in the width direction (B direction) according to JIS P8113:2006, the elongation at break ET in the height direction (A direction) and the elongation at break EH in the width direction (B direction) of the packaging substrate 10 can be determined simultaneously.

[0183] In one embodiment of the present invention, the packaging substrate 10 is used such that the MD direction (paper-making direction, longitudinal direction, T direction) of the paper substrate 100 included in the packaging substrate 10 is aligned with the height direction (A direction) of the packaging substrate 10 of the packaging body 1, and the CD direction (direction orthogonal to the paper-making direction, transverse direction, Y direction) of the paper substrate 100 included in the packaging substrate 10 is aligned with the width direction (B direction) of the packaging substrate 10 of the packaging body 1. However, in the present invention, the orientation of the packaging substrate 10 of the packaging body 1 is not limited to this. In another embodiment of the present invention, the packaging substrate 10 is used such that the MD direction (paper-making direction, longitudinal direction, T direction) of the paper substrate 100 included in the packaging substrate 10 is aligned with the width direction (B direction) of the packaging substrate 10 of the packaging body 1, and the CD direction (direction orthogonal to the paper-making direction, transverse direction, Y direction) of the paper substrate 100 included in the packaging substrate 10 is aligned with the height direction (A direction) of the packaging substrate 10 of the packaging body 1.

[0184] The geometric mean elongation at break of the packaging substrate 10 can be controlled by adjusting the elongation at break in the height direction and the elongation at break in the width direction of the packaging substrate 10. As mentioned above, the height direction of the packaging substrate 10 corresponds to the MD direction or CD direction of the packaging substrate 10, and the width direction of the packaging substrate 10 corresponds to the CD direction or MD direction of the packaging substrate 10. Therefore, the geometric mean elongation at break of the packaging substrate 10 can be interpreted as the geometric mean elongation at break of the packaging substrate 10 in the MD direction (paper-making direction, longitudinal direction, T direction) and the packaging substrate 10 in the CD direction (direction orthogonal to the paper-making direction, transverse direction, Y direction), and can be controlled by adjusting the elongation at break in the MD direction and the elongation at break in the CD direction of the packaging substrate 10.

[0185] The elongation at break in the MD direction and the elongation at break in the CD direction of the packaging substrate 10 can be adjusted by changing any one or a combination of two or more of the following conditions: (1) adjustment of the ratio of softwood pulp to hardwood pulp during papermaking of the paper substrate 100, (2) adjustment of the beating degree, and (3) the type of sealant used for the sealing layer during the manufacturing of the packaging substrate 10, and (4) the basis weight of the sealing layer.

[0186] (Effects of the first embodiment)

[0187] The first embodiment of the present invention is a toilet paper roll package containing multiple toilet paper rolls packaged in a packaging substrate. The packaging substrate has a layered structure, comprising a paper substrate and a sealing layer for sealing the package. The thickness of the packaging substrate is 35 μm or more and 80 μm or less. The burst strength of the packaging substrate is 105 kPa or more and 190 kPa or less. The geometric mean elongation at break of the packaging substrate in the height direction parallel to the axial direction of the toilet paper rolls contained within the package, and in the width direction perpendicular to the axial direction of the toilet paper rolls contained within the package, is 2.9% or more and 6.0% or less.

[0188] The toilet paper roll packaging 1 of the first embodiment achieves the following special effects by ensuring that the thickness, bursting strength, and geometric mean elongation at break of the packaging substrate 10 are within the range specified above: the packaging substrate 10 is easy to bend, the packaging 1 has excellent processability during manufacturing, it is not easy to break due to finger pressure when the packaging 1 is pinched, and the packaging 1 is easy to open when opening; and after opening, when a portion of the multiple toilet paper rolls 2 inside the packaging 1 is taken out and the remaining toilet paper rolls 2 are repackaged with the packaging substrate 10, the packaging substrate 10 is easy to bend and it is easy to repackage the packaged 2. In addition, after repackaging, the packaging 1 is not easy to open naturally over time, and the repackaging performance is good.

[0189] <Second Implementation Method>

[0190] Next, the second embodiment of the present invention will be described. Unless otherwise specified, the structure applicable to the first embodiment can be applied to this embodiment.

[0191] The second embodiment of the present invention is a preferred embodiment of the first embodiment, characterized in that the air permeability of the packaging substrate 10 is 1,000 seconds or more. Preferably, the air permeability of the packaging substrate 10 is 10,000 seconds or more, and more preferably 20,000 seconds or more.

[0192] The air permeability of the packaging substrate 10 was measured at the non-sealed portion (joint portion of the packaging substrate 10) N12 of the packaging body 1.

[0193] The air permeability (Wang Yanshi) of the packaging substrate 10 can be calculated as an average value. It is the average value of the air permeability (surface air permeability) measured by the Wang Yanshi air permeability tester according to JIS P8117:2009, with the surface of the packaging substrate 10 (the outer side of the packaging body 1) as the measuring surface and the back side of the packaging substrate 10 (the inner side of the packaging body 1, i.e., the side that contacts the toilet paper roll 2, which is the packaged body of the packaging body 1) as the measuring surface and the back side air permeability (back air permeability) as the measuring surface.

[0194] (Effects)

[0195] The higher the air permeability (the greater the number of seconds), the more difficult it is for air to pass through, and the poorer the ventilation. If the air permeability of the packaging substrate 10 is 1000 seconds or more, it can prevent the transfer of external odors to the packaged body (toilet paper roll) 2 inside the packaging body 1 during storage in a warehouse or display in a store.

[0196] (Implementation method)

[0197] To achieve an air permeability of 1000 seconds or more for the packaging substrate 10, a highly permeable paper substrate can be used as the paper substrate 100 contained in the packaging substrate 10. Cellophane is an example of such a paper substrate. Alternatively, another method for achieving an air permeability of 1000 seconds or more for the packaging substrate 10 is to completely cover one side of the paper substrate 100 with a sealing layer 110. The sealing layer 110 can be further improved by using a sealing layer obtained by extruding a thermoplastic resin or a composition containing a thermoplastic resin, or by attaching a film formed of thermoplastic resin or a film containing a thermoplastic resin using a lamination processing device.

[0198] <Third Implementation Method>

[0199] Next, the third embodiment of the present invention will be described. Unless otherwise specified, structures applicable to the above embodiments can be applied to this embodiment.

[0200] The third embodiment of the present invention is a preferred embodiment of the above-described embodiments. The toilet paper roll packaging body 1 is characterized in that the bending stiffness in the width direction of the packaging substrate 10 is 8 μNm or more and 35 μNm or less. Preferably, the bending stiffness in the width direction of the packaging substrate 10 is 10 μNm or more and 30 μNm or less, more preferably 15 μNm or more and 25 μNm or less.

[0201] The bending stiffness of the packaging substrate 10 was measured at the non-sealed part (joint part of the packaging substrate 10) N12 of the packaging body 1.

[0202] The bending stiffness of the packaging substrate 10 can be determined using a bending tester such as the L&W bending tester (manufactured by Lorentzen & Wettre) according to the method described in JIS P8125-1:2017. Specifically, for a test piece of packaging substrate 10 with a width of 38 mm and a length of 100 mm, the measured value when the bending angle is set to 15 degrees and the bending length (span of the test stand) is set to 10 mm is taken as the bending resistance (load), and the bending stiffness (μN·m) is calculated using the following formula (II).

[0203] Bending stiffness (μN·m) = 60 × bending resistance (mN) × bending length 10 (mm) 2 ÷(π × bending angle 15 (°) × sample width 38 (mm))···(II)

[0204] The width direction of the packaging substrate 10 is relative to the axial direction of the toilet paper roll 2 inside the packaging body 1 (in FIG. 2 In the diagram, the direction perpendicular to arrow A (direction A) is... FIG. 3 and FIG. 1 In the plan view, direction B is indicated by arrow B. The bending stiffness when the width direction of the packaging substrate 10 (direction B as indicated by arrow B in the figure) is taken as the length direction of the test piece is the bending stiffness in the width direction of the packaging substrate 10. When a test piece with a length of 100mm cannot be used, the length of the test piece can be shortened.

[0205] (Effects)

[0206] If the bending stiffness in the width direction of the packaging substrate 10 is too low, its rigidity is low, making it prone to breakage and resulting in poor processability during manufacturing. If the bending stiffness in the width direction of the packaging substrate 10 increases, the packaging substrate 10 becomes difficult to bend, leading to poor repackaging properties. If the bending stiffness in the width direction of the packaging substrate 10 is 8 μNm or more and 35 μNm or less, the processability during manufacturing is good, and a packaging body 1 with good repackaging properties can be obtained.

[0207] (Implementation method)

[0208] The bending stiffness of the packaging substrate 10 is greatly affected by its thickness (paper thickness). If the thickness is reduced, it is easier to bend but also easier to break. One method to reduce the thickness (paper thickness) is to adjust the basis weight of the paper substrate 100 during papermaking. Generally, the greater the basis weight of the paper substrate 100, the thicker the paper (paper thickness), and the smaller the basis weight of the paper substrate 100, the thinner the paper (paper thickness).

[0209] <Fourth Implementation Method>

[0210] Next, the fourth embodiment of the present invention will be described. Unless otherwise specified, structures applicable to the above embodiments can be applied to this embodiment.

[0211] The fourth embodiment of the present invention is a preferred embodiment of the above-described embodiments. The toilet paper roll packaging body 1 is characterized in that the smoothness of the surface of the packaging substrate 10 (the back side of the packaging substrate 10) that contacts the packaged object (toilet paper roll) 2 inside the packaging body 1 is 100 seconds or more. More preferably, the smoothness of the back side of the packaging substrate 10 is 300 seconds or more, and even more preferably 500 seconds or more.

[0212] The smoothness of the back side of the packaging substrate 10 was measured at the non-sealed portion (joint portion of the packaging substrate 10) N12 of the packaging body 1.

[0213] The smoothness (Wang Yanshi) of the packaging substrate 10 can be measured according to JIS P8155:2010.

[0214] (Effects)

[0215] If the smoothness of the surface of the packaging substrate 10 (the back side of the packaging substrate 10) that contacts the packaged object (toilet paper roll) 2 inside the packaging body 1 is less than 100 seconds, friction will occur between the packaged object 2 and the packaging substrate 10 due to the surface roughness during the manufacturing of the packaging body 1 and during vibrations generated in the manufactured packaging body 1, and the surface smoothness of the packaged object will easily decrease. If the smoothness of the back side of the packaging substrate 10 is 100 seconds or more, the phenomenon of decreased surface smoothness of the packaged object is less likely to occur.

[0216] (Implementation method)

[0217] Examples of methods for setting the smoothness of the packaging substrate 10 to 100 seconds or more include: using paper with high original smoothness as the paper substrate 100 of the packaging substrate 10; adjusting the smoothness by strengthening the calendering process conditions of paper with low smoothness to produce the paper substrate 100 of the packaging substrate 10; and using the side with high smoothness (glossy side) as the back side of the packaging substrate 10 when using paper with differences between the inside and outside, such as single-sided glossy paper, as the paper substrate 100.

[0218] <Other>

[0219] (1) Packaging form of packaging body 1

[0220] In the above embodiments, a candy-style packaging form was given as an example of the packaging form of the packaging body 1, but the packaging form applicable to the present invention is not limited to this. The packaging form of the packaging body 1 according to the embodiments of the present invention can adopt any known packaging form, such as a corner brace packaging form. In detail, as long as it is feasible and without contradiction, in the joining of the packaging substrate 10 used to encapsulate the packaging body 1, any combination of joining methods such as overlapping by bonding different surfaces of the packaging substrate 10 and butt bonding by bonding the same surface of the packaging substrate 10 can be used.

[0221] In the above embodiment, a candy-style packaging form is adopted, with the sealing layer 110 of the packaging substrate 10 serving as the outer side of the packaging body 1. However, the embodiments of the present invention are not limited to this. For example, in the case of using a gusseted packaging form or a bonding packaging form, the sealing layer 110 of the packaging substrate 10 can also be used as the inner side of the packaging body 1.

[0222] In a packaging form in which the sealing layer 110 of the packaging substrate 10 is used as the outer side of the packaging body 1, if the sealing layer 110 is a heat-sealing layer, and if a strip handle made of paper substrate is to be installed on the packaging body 1, the sealing layer 110 of the packaging substrate 10 of the packaging body 1 can be used in the connection between the handle and the main body of the packaging body.

[0223] (2) Layer structure of packaging substrate 10

[0224] In one embodiment of the present invention, other layers besides the sealing layer 110 may be provided on the packaging substrate 10. Examples of other layers include functional layers such as a water vapor barrier layer, an oxygen barrier layer, a printing layer, a printability-enhancing layer, an overprinting layer, and a light-shielding layer. These other layers may be provided as needed, for example, on the surface of the packaging substrate 10, which is the outer side of the packaging body 1; on the back side of the packaging substrate 10, which is the inner side of the packaging body 1; between the paper substrate 100 and the sealing layer 110; or on top of the sealing layer 110 in a manner that does not impair the adhesion or heat-sealing properties of the sealing layer. Other layers may be one layer or multiple layers, including two or more layers.

[0225] When the packaging substrate 10 includes other layers, the physical properties of the packaging substrate 10 according to the embodiments of the present invention are also measured in the non-sealed portion (joint portion of the packaging substrate 10) N12 of the packaging body 1. Therefore, for example, when the non-sealed portion N12 of the packaging body 1 includes a layer with a certain function as described above (hereinafter also referred to as a functional layer), the thickness (paper thickness) of the packaging substrate 10 becomes a thickness including the thickness of the paper substrate and the thickness of the functional layer. In addition, when the non-sealed portion N12 of the packaging body 1 does not include the sealing layer 110 and the functional layer as described above, the thickness (paper thickness) of the packaging substrate 10 is substantially the thickness of the paper substrate.

[0226] (3) The proportion (by weight) of paper substrate in packaging substrate 10

[0227] In one embodiment of the present invention, the proportion (mass ratio) of paper substrate 100 in the packaging substrate 10 is preferably 51% by mass or more.

[0228] The proportion of paper substrate, which is the percentage of the weight of paper substrate to the weight of packaging substrate, can be calculated using the formula [(weight of paper substrate) ÷ (weight of packaging substrate) × 100] (unit: %).

[0229] It should be noted that the basis weight of the packaging substrate used when calculating the proportion of the paper substrate includes the basis weight of the non-bonded portion N12 and the bonded portions (12S, 12T, 12B) of the packaging substrate 10. Components other than the paper substrate 100 constituting the packaging substrate 10 include the sealant contained in the sealing layer 110, the functional materials contained in the aforementioned functional layer, and, for example, resin components. These components other than the paper substrate 100 preferably exhibit biodegradability.

[0230] Under Japan's Resource Effective Utilization Promotion Law, in the case of composite materials made of plastic and paper, it is required to identify and mark the main materials in terms of quality. That is, if the proportion of plastic in the packaging substrate 10 exceeds 50% by mass, a plastic mark must be displayed, and if the proportion of paper exceeds 50% by mass, a paper mark must be displayed.

[0231] If the proportion (by weight) of paper substrate 100 in the packaging substrate 10 is 51% or more, paper markings can be displayed on the packaging substrate 10. By displaying paper markings, the packaging substrate 10 of the packaging body 1 can be discarded in the same way as paper.

[0232] In addition, if the proportion (by mass) of paper substrate 100 in the packaging substrate 10 is 51% or more, then compared with the 100% resin-based packaging films commonly used in toilet paper roll packaging, such as polyethylene film and polypropylene film, which are excluding biodegradability, the amount of resin used is significantly reduced, thus enabling the removal and reduction of plastics.

[0233] (3) Handles of the packaging

[0234] The packaging body 1 according to the embodiments of the present invention may also include a handle (not shown) for handling the packaging body 1. It should be noted that the handle is not an essential component of the present invention. The handle may be, for example, a strip-shaped handle whose two ends are joined to the outside of the main body of the packaging body. The material of the handle may be a film or a paper-based substrate (paper substrate).

[0235] If the sealant contained in the sealing layer 110 of the packaging substrate 10 of the packaging body 1 is a heat sealant, and the material of the handle is set to be a paper substrate, then the connection between the handle and the main body of the packaging body can be achieved using the sealing layer 110 of the packaging substrate 10 of the packaging body 1, which is therefore preferred.

[0236] (Example)

[0237] The present invention will now be described with reference to embodiments and comparative examples. It should be noted that the present invention is not limited to the embodiments shown below.

[0238] (Example 1)

[0239] Cellophane is used as the paper substrate. A film is formed on the entire surface of one side of the paper substrate by extrusion to form a 15μm thick polyethylene layer as a sealing layer, thus obtaining the packaging substrate.

[0240] Two rolls of kitchen paper (230mm wide, 115mm in diameter, and 22.7m long) configured as two horizontal columns and one vertical layer were used as the packaging body. The resulting packaging substrate was used, with the sealing layer of the substrate forming the outer side of the packaging body, and packaged in a candy-like manner. FIG. 1 The packaging body of Example 1 is shown. At this time, the kitchen paper roll is oriented axially (in...) FIG. 3 In this case, the packaging substrate is used to wrap the packaged item in a manner parallel to the MD direction of the paper substrate (indicated by arrow A).

[0241] (Examples 2-4, Comparative Examples 1 and 2)

[0242] Using a paper substrate (glass paper) with a different basis weight than that of Example 1, the same procedure was followed as in Example 1 to obtain the packaging bodies of Examples 2-4, as well as Comparative Examples 1 and 2. Starting with the example with the lowest basis weight of the paper substrate, the examples are: Comparative Example 1, Example 3, Example 2, Example 1, Example 4, and Comparative Example 2.

[0243] (Examples 5 and 6, Comparative Examples 3 and 4)

[0244] Using a paper substrate (glasspaper) with a different amount of added paper reinforcing agent than that of Example 1, the same procedure was followed as in Example 1 to obtain the packaging bodies of Examples 5 and 6, and Comparative Examples 3 and 4. The paper substrates of Examples 5 and 3 contained less paper reinforcing agent than the paper substrate of Example 1. The paper substrates of Examples 6 and 4 contained more paper reinforcing agent than the paper substrate of Example 1.

[0245] (Example 7, Example 8)

[0246] Using a paper substrate (glass paper) with a different T / Y ratio than that of Example 1, the same procedure was followed as in Example 1 to obtain the packaging bodies of Examples 7 and 8.

[0247] Here, the so-called "T / Y ratio" is a directional index of tensile strength based on the orientation of the pulp fibers that make up the paper substrate. It is the ratio of the strength in the two directions when the paper flow direction (MD direction) in the paper machine is taken as the longitudinal direction (T) and the direction perpendicular to it (CD direction) is taken as the transverse direction (Y). It is also called the "longitudinal-to-transverse ratio".

[0248] The paper substrate of Example 7 has a smaller T / Y ratio than the paper substrate of Example 1. The paper substrate of Example 8 has a larger T / Y ratio than the paper substrate of Example 1. For example, the T / Y ratio can be controlled by adjusting the jetting wire ratio (J / W), which is the ratio of the jetting speed (J) to the wire speed (W) of the pulp dispersion in the paper machine during papermaking.

[0249] (Example 9)

[0250] As the paper substrate, single-sided glossy paper was used instead of cellophane, and the procedure was the same as in Example 1 to obtain the packaging body of Example 9. In this case, the sealing layer was applied to the non-glossy surface, which has relatively lower smoothness, on both sides of the single-sided glossy paper. Furthermore, the glossy surface, which has relatively higher smoothness, was used as the side that contacts the kitchen paper roll inside the packaging body. It should be noted that the basis weight of the paper substrate (single-sided glossy paper) in Example 9 was 30.0 g / m². 2 The basis weight of the paper substrate (glass paper) is lower than that of Example 1 (40.0 / m²). 2 The basis weight of the paper substrate (cellophane) in Example 2 (30.5 g / m²) is compared with that of the paper substrate (cellophane) in Example 2. 2 () are of the same degree.

[0251] (Example 10)

[0252] Instead of forming a sealing layer by extruding a polyethylene film on the entire single side of a paper substrate, a sealing layer is formed on a portion of a single side of the paper substrate. FIG. 3 A heat-sealing layer was formed by applying a heat-sealing agent to the designated area (shown by the shaded line in (a)) which serves as the joint of the packaging substrate. This process was repeated in the same manner as in Example 1, resulting in the packaging body of Example 10. A polyolefin-based water-based heat-sealing agent was used as the heat-sealing agent, and the coating was applied using a roller coater.

[0253] (Compare Examples 5 and 6)

[0254] Using a paper substrate (cellophane) with a different basis weight than that of Example 10, the same procedure was followed as in Example 10 to obtain the packaging bodies of Comparative Examples 5 and 6. Starting with the examples with lower basis weights of the paper substrate, they are listed sequentially as Comparative Example 6, Comparative Example 5, and Example 10.

[0255] (Comparative Example 7)

[0256] Instead of cellophane, single-sided glossy paper is used as the paper substrate. Instead of forming a sealing layer by extruding a polyethylene layer onto the entire single side of the paper substrate, the sealing layer is formed on a portion of the single side of the paper substrate. FIG. 4 A heat-sealing layer was formed by applying a heat-sealing agent to the designated area (shown by the shaded line in (a)) that serves as the joint of the packaging substrate. This process was repeated in the same manner as in Example 1, resulting in the packaging body of Comparative Example 7. In this case, the heat-sealing layer was applied to the entire non-glossy surface, i.e., the surface with relatively low smoothness among the two sides of the single-sided glossy paper. The glossy surface, with relatively high smoothness among the two sides of the single-sided glossy paper, was used as the side that contacts the kitchen paper roll contained within the packaging body. A polyolefin-based water-based heat-sealing agent was used as the heat-sealing agent, as in Example 10, and the coating was applied using a roller coater.

[0257] It should be noted that the basis weight of the paper substrate (single-sided glossy paper) in Comparative Example 7 is 50.5 g / m². 2 The basis weight of the paper substrate (cellophane) compared to Example 1 (40.0 / m²) 2 )high.

[0258] (Physical properties of packaging substrate)

[0259] The physical properties of the paper substrates and packaging substrates used in each example are shown in Tables 1 to 4. The samples were conditioned for 48 hours in an environment based on Japanese Industrial Standard JIS P8111 (temperature 23±1℃, humidity 50±2%RH), and the physical properties were measured in an environment based on JIS P8111.

[0260] (Basis weight of paper substrate)

[0261] The basis weight (unit: g / m²) of each sheet of paper substrate was determined according to JIS P8124. 2 ).

[0262] (Gram weight of packaging substrate)

[0263] The basis weight (in g / m²) of each packaging substrate was determined according to JIS P8124. 2 During the measurement, the non-sealed area of ​​the packaging body (the non-jointed area of ​​the packaging substrate) is measured, avoiding the sealed part of the packaging body (the joint part of the packaging substrate).

[0264] (Weight of the sealing layer)

[0265] For the examples of sealing layers formed by film extrusion (Examples 1-9 and Comparative Examples 1-4), the basis weight of the sealing layer is a calculated value obtained by subtracting the basis weight of the paper substrate from the basis weight of the packaging substrate obtained by the above-described measurement method, and is obtained by the formula "(basis weight of packaging substrate) - (basis weight of paper substrate)" (unit: g / m³). 2 ).

[0266] (Amount of sealant coating)

[0267] For each example of forming a sealing layer by coating with a roller coater (Example 10 and Comparative Examples 5-7), the basis weight of the sealing layer is determined as the amount of sealant applied per unit area in the sealant coating section of the packaging substrate.

[0268] (Thickness of packaging substrate (paper thickness))

[0269] The thickness (paper thickness) of the packaging substrate (unit: μm) was determined according to ISO 534:2011. The pressure on the pressure surface during measurement was set to 100 kPa ± 10 kPa. The measurement was performed on the non-sealed areas of the packaging, avoiding the sealed portion.

[0270] (Density of packaging substrate)

[0271] The density of the packaging substrate is a calculated value obtained from the basis weight and thickness (paper thickness) of the packaging substrate obtained by the above-mentioned measurement method, and is calculated using the formula "(basis weight of packaging substrate) ÷ (thickness (paper thickness))" (unit: g / cm³). 3 ).

[0272] (Smoothness of packaging substrate)

[0273] The smoothness of the back side of the packaging substrate was measured according to JIS P8155:2011 (Wang Yan method) (unit: seconds). During the measurement, the non-sealed area of ​​the packaging body was avoided. The side of the packaging substrate that is in contact with the kitchen paper roll inside the packaging body is referred to as the "back side of the packaging substrate".

[0274] (Air permeability of packaging substrate)

[0275] According to JIS P8117:2009, the air permeability of the front and back surfaces of the packaging substrate was measured (Wang Yan's method), and the average value of the air permeability of the two surfaces was calculated as the air permeability of the packaging substrate (unit: seconds). During the measurement, the non-sealed areas of the packaging body were avoided. The side of the packaging substrate that is in contact with the kitchen paper roll inside the packaging body is referred to as the "back surface of the packaging substrate", and the side of the packaging substrate that is the outer side of the packaging body is referred to as the "front surface of the packaging substrate".

[0276] (Transparency of packaging substrate)

[0277] The transparency (in %) of the packaging substrate was measured using a diffuse light transmittance meter DOT-5 (manufactured by Murakami Color Technology Research Institute Co., Ltd.) in accordance with ISO 5-2. During the measurement, the non-sealed area of ​​the packaging (the non-jointed area of ​​the packaging substrate) was measured, avoiding the sealed part of the packaging body.

[0278] (Burning strength of packaging substrate)

[0279] The bursting strength (unit: kPa) of the packaging substrate was determined according to JIS P8112:2008. During the test, the non-sealed area of ​​the packaging (the non-jointed area of ​​the packaging substrate) was measured, avoiding the sealed part of the packaging body.

[0280] (Tensile strength of packaging substrate)

[0281] The longitudinal and transverse tensile strengths (unit: kN / m) of the packaging substrate were determined according to JIS P8113:2006. During the measurement, the non-sealed areas of the packaging (non-jointed areas of the packaging substrate) were measured, avoiding the sealed portion of the packaging body.

[0282] (Elongation at break of packaging substrate)

[0283] The elongation at break of the packaging substrate can be measured simultaneously with the tensile strength of the packaging substrate. When measuring the longitudinal and transverse tensile strength of the packaging substrate, the elongation at break of the packaging substrate in the longitudinal and transverse directions is also measured, and these are referred to as the elongation at break (in %) of the packaging substrate in the height and width directions.

[0284] (Geometric mean elongation at break of packaging substrate)

[0285] The geometric mean elongation at break (GE) of the packaging substrate is the geometric mean of the elongation at break in the height direction (ET) and the elongation at break in the width direction (EH) of the packaging substrate, obtained by the above measurement method. It is expressed by the formula: "{Elongation at break in the height direction (ET) × Elongation at break in the width direction (EH) of the packaging substrate}".

[0286] 1 / 2 "The result is (unit: %)."

[0287] (Bending stiffness of packaging substrate)

[0288] The bending stiffness (unit: μN·m) of the packaging substrate in the height and width directions was determined using an L&W bending tester (manufactured by Lorentzen & Wettre) according to JIS P8125-1:2017. Specifically, regarding bending stiffness, for a test piece of packaging substrate 10 with a width of 38 mm and a length of 100 mm, the measured value when the bending angle was set to 15 degrees and the bending length (span of the test stand) was set to 10 mm was taken as the bending resistance (load), and the bending stiffness was calculated using the following formula.

[0289] Bending stiffness (μN·m) = 60 × bending resistance (mN) × bending length 10 (mm) 2÷(π × bending angle 15 (°) × sample width 38 (mm))

[0290] During measurement, the non-sealed portion (non-jointed portion of the packaging substrate) of the packaging body is measured, avoiding the sealed portion (joint portion of the packaging substrate). The direction of the packaging substrate parallel to the axis of the toilet paper roll inside the packaging body is defined as the "height direction of the packaging substrate," and the direction of the packaging substrate perpendicular to the axis of the toilet paper roll inside the packaging body is defined as the "width direction of the packaging substrate." The bending stiffness when the longitudinal direction of the packaging substrate is taken as the length direction of the test piece is defined as the "longitudinal bending stiffness of the packaging substrate," and the bending stiffness when the width direction of the packaging substrate is taken as the length direction of the test piece is defined as the "width direction bending stiffness of the packaging substrate."

[0291] (Sensory test)

[0292] The following sensory tests were conducted on the packages obtained in each example.

[0293] (Tear resistance of packaging substrate)

[0294] Observe whether the packaging material breaks at the point of pressure applied when the package is handled by one hand. One tester conducts the test on 20 packages in each example, and evaluates the proportion of packages that do not break on a four-level scale. The higher the evaluation value, the better (4 (excellent) → 1 (poor)).

[0295] (Ease of repackaging the packaged item)

[0296] The ease of repackaging was assessed by 30 participants when the packages were manually opened, one of the two inner rolls of kitchen paper was removed, and the remaining kitchen paper roll was used as the repackaged item, with the outside of the kitchen paper roll not exposed. The evaluation also assessed whether the repackaged package would open over time. The opening and repackaging methods used in the experiment are shown in the figures. FIG. 5 and ​ However, this is not the only factor; the evaluation is delegated to individual testers. The higher the evaluation value, the better (4 (excellent) → 1 (poor)).

[0297] (Transfer of odor to the packaged product)

[0298] The packaging materials obtained in each example and a non-woven juice extraction bag containing 30g of coffee powder were placed in a zip-locked plastic bag (Unipap (registered trademark) L-8 (340mm×480mm, 0.08mm thickness). After sealing, the bags were stored at 23°C and 50% RH for one week. The stored packaging materials were then removed from the plastic bag and opened. Five testers rated the coffee odor detected from the kitchen paper roll according to the following criteria. The rating values ​​shown in the table are the average of the five testers' ratings, rounded off. A higher rating indicates a less noticeable odor, indicating a better result (3 (excellent) → 1 (poor)).

[0299] 3: You can hardly detect any off-flavors in the coffee.

[0300] 2: A slight off-odor was detected in the coffee.

[0301] 1: I strongly smelled an off-odor in the coffee.

[0302] (The visibility of the packaged item)

[0303] For each package obtained, 30 testers evaluated the ease with which the condition (embossing, perforation, color) of the packaged item (kitchen paper roll) could be identified from the outside of the package. A higher evaluation value indicated better visibility.

[0304] (4 (excellent) → 1 (poor))

[0305] (Experimental Results)

[0306] The test results are shown in Tables 1 to 4. It should be noted that, since the non-jointed portions of the packaging substrates in Examples 10 and Comparative Examples 5 to 7 do not have a sealing layer, the physical properties of the packaging substrates in Examples 10 and Comparative Examples 5 to 7 are essentially the physical properties of paper substrates.

[0307] (Table 1)

[0308]

[0309] (Table 2)

[0310]

[0311] (Table 3)

[0312]

[0313] (Table 4)

[0314]

[0315] Examples 1 to Comparative Examples 7 (all samples) were kitchen paper roll packages containing two toilet paper rolls wrapped in a packaging substrate, wherein the packaging substrate had a layer structure including a paper substrate and a sealing layer for sealing the package.

[0316] As shown in Tables 1 and 2, the kitchen paper roll packaging bodies of Examples 1 to 10 all meet the following requirements: the thickness of the packaging substrate is 35 μm or more and 80 μm or less; the bursting strength of the packaging substrate is 105 kPa or more and 190 kPa or less; and the geometric mean elongation at break of the packaging substrate in the height direction parallel to the axial direction of the kitchen paper roll inside the packaging body and the elongation at break in the width direction perpendicular to the axial direction of the kitchen paper roll inside the packaging body is 2.9% or more and 6.0% or less.

[0317] The "tear resistance of the packaging substrate" (evaluated in four levels) of the kitchen paper roll packaging bodies of Examples 1 to 10 were all rated as 3 (good) or 4 (excellent), and they were not easily broken when handled by pinching with fingers.

[0318] In addition, the "ease of repackaging of the packaged object" (evaluated on a four-level scale) was rated as 2 (pass) in Example 4, where the basis weight of the paper substrate and the packaging substrate is relatively high and the thickness of the packaging substrate (paper thickness) is relatively high; in Example 6, where the amount of paper strengthening agent added during papermaking of the paper substrate is relatively large; and in Example 7, where the T / Y ratio of the paper substrate is relatively low and the anisotropy is small. In other examples, it was rated as 3 (good) or 4 (excellent), indicating that the packaged object is easy to repackage.

[0319] In addition, the "transfer of odor to the packaged body" (evaluated on a three-level scale) was rated as 2 in Example 10, where the sealing layer was set by coating a water-based sealant, indicating a slight transfer of odor. However, in Examples 1-9, where the sealing layer was set by extrusion film preparation, the rating was 3, indicating almost no transfer of odor, which was considered good.

[0320] In addition, the "visibility of the packaged object" (evaluated on a four-level scale) was rated as 2 in Example 9, where the paper substrate was single-sided glossy paper, indicating slightly low visibility. However, for Examples 1-3, 5-8, and 10, where the paper substrate was glassine paper, the rating was 4, indicating excellent visibility.

[0321] Compared to Examples 1-3, the paper substrate and therefore the packaging substrate of Comparative Example 1 had a lower basis weight. The thickness of the packaging substrate of Comparative Example 1 was 37 μm, which is within the range specified in this invention, but its burst strength (90 kPa) and geometric mean elongation at break (2.40%) were outside the range specified in this invention, and its values ​​were low. The "bursting resistance of the packaging substrate" was rated 1 (poor), indicating it was prone to breakage. Furthermore, the bending stiffness (width direction) of Comparative Example 1 was 6.5 μNm, which was lower than that of the examples, indicating it was easy to bend. The "ease of repackaging the packaged object" was rated 4, which is excellent.

[0322] Compared to Examples 1 and 4, the paper substrate and therefore the packaging substrate of Comparative Example 2 has a higher basis weight. The thickness of the packaging substrate of Comparative Example 2 is 78 μm, which is within the range specified in this invention, but its burst strength (233 kPa) and geometric mean elongation at break (6.13%) are outside the range specified in this invention and are therefore high. Furthermore, the bending stiffness (width direction) of Comparative Example 2 is 49.8 μNm, which is higher than that of the examples. The "ease of repackaging the packaged object" rating for Comparative Example 2 is 1, which is poor. Additionally, the transparency of Comparative Example 2 is 57.0%, which is lower than that of the examples, and the "visibility of the packaged object" rating (out of four levels) is 1, which is poor.

[0323] Compared to Example 1, the amount of paper strengthening agent added during papermaking of the paper substrate in Comparative Example 3 was less. The thickness of the packaging substrate in Comparative Example 3 was 52 μm, which is within the range specified in this invention. However, the bursting strength (99 kPa) and geometric mean elongation at break (2.33%) of Comparative Example 3 were outside the range specified in this invention, and their values ​​were low. The "bursting resistance of the packaging substrate" was rated 1, which is poor. Furthermore, the bending stiffness (width direction) of Comparative Example 3 was 4.1 μNm, which is lower than that of Example 1 (20.1 μNm). The "ease of repackaging the packaged object" was rated 4, which is excellent.

[0324] Compared to Example 1, the paper substrate of Comparative Example 4 had a higher amount of paper strengthening agent added during papermaking. The thickness of the packaging substrate of Comparative Example 4 was 52 μm, which is within the range specified in this invention; however, the burst strength (202 kPa) of Comparative Example 4 was outside the range specified in this invention, and its value was high. Furthermore, although the geometric mean elongation at break (5.59%) was within the range specified in this invention, its value was relatively high. Additionally, the flexural stiffness (width direction) of Comparative Example 4 was 33.5 μNm, which was higher than that of Example 1 (20.1 μNm). The "ease of repackaging the packaged object" of Comparative Example 4 was rated as 1, which is poor.

[0325] Compared to Example 2, Comparative Example 5, although having the same basis weight of paper substrate, had a different sealant coating method, resulting in a lower coating amount (basis weight) of the sealing layer. The packaging substrate thickness of Comparative Example 5 was 29 μm, which is thinner and outside the scope of this invention; its "odor transfer to the packaged object" rating was 2, worse than Example 2. The bursting strength (96 kPa) and geometric mean elongation at break (2.63%) of Comparative Example 5 were also outside the scope of this invention, and their values ​​were low; its "bursting resistance of the packaging substrate" rating was 1, poor. Furthermore, the flexural stiffness (width direction) of Comparative Example 5 was 8.7 μNm, lower than Example 2 (12.1 μNm); its "ease of repackaging the packaged object" rating was 4, excellent.

[0326] Compared to Example 3, Comparative Example 6, although having the same basis weight of paper substrate, had a different sealant coating method, resulting in a lower coating amount (basis weight) of the sealing layer. The packaging substrate of Comparative Example 6 had a thickness of 25 μm, which is thinner than the limits specified in this invention, and its "odor transfer to the packaged object" rating was 2, worse than Example 3. The bursting strength (91 kPa) and geometric mean elongation at break (2.46%) of Comparative Example 6 were also low, falling outside the limits specified in this invention, and its "bursting resistance of the packaging substrate" rating was 1, poor. Furthermore, the flexural stiffness (width direction) of Comparative Example 6 was 4.8 μNm, lower than Example 3 (8.1 μNm), and its "ease of repackaging the packaged object" rating was 4, excellent.

[0327] Compared to Example 9, Comparative Example 7 used the same type of packaging substrate—single-sided glossy paper—but the sealant coating method differed, resulting in a lower coating weight (grammage) of the sealing layer. The thickness of the packaging substrate in Comparative Example 7 was 50 μm, within the range specified in this invention, but thicker than Example 9 (45 μm). The transparency of the packaging substrate in Comparative Example 7 was 57.3%, lower than Example 9 (62.0%). The evaluations for "odor transfer to the packaged object" and "visibility of the packaged object" in Comparative Example 7 were both 1, worse than Example 9. The bursting strength (102 kPa) and geometric mean elongation at break (2.73%) of Comparative Example 7 were outside the range specified in this invention, and their values ​​were low; the "bursting resistance of the packaging substrate" evaluation was 1, indicating poor performance.

[0328] Symbol explanation:

[0329] 1. Toilet paper roll packaging (packaging body)

[0330] 2 rolls of toilet paper (kitchen paper rolls) (packaged)

[0331] 10 Packaging Base Materials

[0332] 100 paper substrate

[0333] 110 Sealing layer (heat sealant layer, adhesive layer).

Claims

1. A toilet paper roll packaging body, which is a toilet paper roll packaging body containing multiple toilet paper rolls using a packaging substrate, characterized in that, The packaging substrate has a layered structure, which includes a paper substrate and a sealing layer for encapsulating the packaging. The thickness of the packaging substrate is 35μm or more and 80μm or less. The burst strength of the packaging substrate is above 105 kPa and below 190 kPa. The geometric mean elongation at break of the packaging substrate in the height direction (parallel to the axial direction of the toilet paper roll inside the packaging body) and in the width direction (perpendicular to the axial direction of the toilet paper roll inside the packaging body) is 2.9% or more and 6.0% or less. The density of the packaging substrate is 0.978 g / cm³. 3 Above and 1.200 g / cm 3 the following.

2. The toilet paper roll packaging body according to claim 1, characterized in that, The air permeability of the packaging substrate is above 1000 seconds.

3. The toilet paper roll packaging body according to claim 1, characterized in that, The bending stiffness of the packaging substrate in the width direction is above 8 μNm and below 35 μNm.

4. The toilet paper roll packaging body according to claim 1, characterized in that, The smoothness of the side of the packaging substrate that contacts the toilet paper roll inside the packaging body is greater than 100 seconds.

5. The toilet paper roll packaging body according to claim 1, characterized in that, The transparency of the packaging substrate is above 60%.

6. The toilet paper roll packaging body according to claim 1, characterized in that, The paper substrate is glassine paper.

7. The toilet paper roll packaging body according to claim 1, characterized in that, The packaging is in the form of candy packaging.

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