Packaging bag and sheet packaging body

Abstract

To provide a paper packaging bag easy to be opened.SOLUTION: A packaging bag accommodates a sheet, and has a substrate containing a paper component. A first coefficient of static friction between an inner surface of the substrate disposed inside the packaging bag and the sheet is smaller than a second coefficient of static friction between an outer surface of the substrate disposed outside the packaging bag and an artificial skin. The first coefficient of static friction is equal to or less than 0.55.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a packaging bag and a sheet packaging body. [Background technology]

[0002] Sheet packages containing sheets such as paper towels and tissue paper are distributed and used with multiple sheets contained in a packaging bag made of resin film (for example, Patent Documents 1 and 2). In recent years, from the perspective of reducing environmental impacts such as global warming due to CO2 emissions and marine pollution caused by microplastics, attention has been focused on changing the material of the packaging bags in sheet packages from resin to paper. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-183034 [Patent Document 2] Japanese Patent Application Publication No. 2018-177364 Summary of the Invention [Problem to be solved by the invention]

[0004] However, paper packaging bags are less flexible than plastic packaging bags, and therefore, when perforations for opening are provided, the perforations are difficult to tear and the bags are difficult to open.

[0005] An object of the present invention is to provide a paper packaging bag that is easy to open. [Means for solving the problem]

[0006] A first aspect of the present invention provides a packaging bag for containing a sheet, the packaging bag having a substrate containing a paper component, wherein a first static friction coefficient between the inner surface of the substrate arranged inside the packaging bag and the sheet is smaller than a second static friction coefficient between the outer surface of the substrate arranged outside the packaging bag and artificial skin, and the first static friction coefficient is 0.55 or less.

[0007] In this specification, paper components are made by agglutinating plant fibers. The inner surface of the substrate placed inside the packaging bag refers to the surface that comes into contact with the sheet contained in the packaging bag. The outer surface of the substrate placed outside the packaging bag refers to the surface that does not come into contact with the sheet contained in the packaging bag. The static friction coefficient refers to the ratio of the friction force generated at the contact surface between two objects when there is no relative motion to the force acting perpendicular to the contact surface. Artificial skin refers to a urethane molded body that imitates human skin.

[0008] In a first aspect, the first static friction coefficient on the inner surface of the substrate containing a paper component is made smaller than the second static friction coefficient on the outer surface of the substrate, and the first static friction coefficient is set to 0.55 or less, thereby making the inner surface of the substrate more slippery against the sheet. Furthermore, because the second static friction coefficient is greater than the first static friction coefficient, the outer surface of the substrate is less slippery against the artificial skin. Therefore, when a paper packaging bag is provided with perforations, the perforations are more easily torn, making it easier to open even a paper packaging bag.

[0009] A second aspect of the present invention provides a packaging bag, wherein the ratio of the first static friction coefficient to the second static friction coefficient is 0.65 or less. The ratio of the first static friction coefficient to the second static friction coefficient indicates the ratio of the first static friction coefficient to the second static friction coefficient.

[0010] In the second aspect, by setting the ratio of the first static friction coefficient to the second static friction coefficient to 0.65 or less, the difference between the friction coefficient of the inner surface of the substrate relative to the sheet and the friction coefficient of the outer surface of the substrate relative to the artificial skin becomes large, making it easier to tear the perforations on the paper packaging bag and opening the packaging bag.

[0011] A third aspect of the present invention provides a packaging bag in which the second static friction coefficient is 1.1 or less. In a paper packaging bag, the difference between the first static friction coefficient and the second friction coefficient should be as large as possible to improve the ease of opening. On the other hand, if the second friction coefficient is too large relative to the first static friction coefficient, there is a risk that the perforations on the paper packaging bag will tear before the packaging bag is opened (for example, during distribution of a sheet package using the packaging bag).

[0012] Therefore, in the third aspect, the second static friction coefficient is adjusted to 1.1 or less so that the outer surface of the substrate does not become too slippery, thereby preventing the packaging bag from unexpectedly tearing without reducing the ease of opening the packaging bag.

[0013] A fourth aspect of the present invention provides a packaging bag, wherein the first static friction coefficient is the static friction coefficient between the CD direction of the substrate and the MD direction of the sheet, and the second static friction coefficient is the static friction coefficient between the CD direction of the substrate and the artificial skin. In this specification, the MD direction is the direction corresponding to the direction in which the substrate travels relative to a papermaking machine that manufactures the substrate that constitutes the paper packaging bag, and the CD direction is the direction corresponding to the direction perpendicular to the travel direction.

[0014] In the fourth aspect, the static friction coefficient between the CD direction of the substrate and the MD direction of the sheet is set to a first static friction coefficient, which makes the CD direction of the substrate more slidable relative to the MD direction of the sheet. Also, the static friction coefficient between the CD direction of the substrate and the artificial skin is set to a second static friction coefficient, which makes the artificial skin less slidable relative to the CD direction of the substrate.

[0015] As a result, if the sheet is placed in a packaging bag with the MD of the sheet aligned with the CD of the substrate and the perforations are formed in the MD of the substrate, the perforations will tear when the thumbs of both hands are pressed against the surface of the packaging bag where the perforations are formed and the thumbs are moved apart in the CD of the substrate. At this time, the perforations tear easily with little force, making the packaging bag even easier to open.

[0016] A fifth aspect of the present invention provides a packaging bag, wherein a tearing score line is formed on the top surface of the packaging bag along the MD direction of the base material. In this specification, the tearing score line refers to a score line (e.g., a perforation) along which cuts and ties (uncut portions between two cuts) are arranged alternately, and when a tie is broken, the adjacent cuts on both sides become continuous cuts.

[0017] In the fifth aspect, by forming a tear score line along the MD direction of the substrate on the top surface of the packaging bag, the tear score line can be torn by simply pressing the top surface of the packaging bag with the thumbs of both hands and moving the thumbs apart in the CD direction of the substrate, so that the packaging bag can be easily opened. In addition, the torn tear score line can form the sheet removal opening formed on the top surface of the packaging bag.

[0018] A sixth aspect of the present invention provides a sheet packaging body having the packaging bag according to any one of the first to fifth aspects and a sheet contained in the packaging bag. In the sixth aspect, by configuring a sheet packaging body in which a sheet is contained in the above-mentioned packaging bag, the same effects as the above-mentioned packaging bag can be obtained. That is, according to the sixth aspect, even if the packaging bag constituting the sheet packaging body is made of paper, it is possible to provide a sheet packaging body in which the paper packaging bag is easy to open. [Effects of the Invention]

[0019] According to one aspect of the present invention, it is possible to provide a paper packaging bag that is easy to open. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 10 is a diagram showing a sheet package in which sheets are housed in a packaging bag. [Figure 2] FIG. 10 is a diagram showing a sheet contained in a packaging bag. [Figure 3] 2 is a view of the sheet wrapping body of FIG. 1 as seen from the top side. FIG. [Figure 4] 2 is a view of the sheet wrapping body of FIG. 1 as seen from the bottom side. FIG. [Figure 5] 2 is a front view of the sheet wrapping body of FIG. 1. FIG. [Figure 6] 2 is a view of the sheet wrapping body of FIG. 1 as seen from the rear side. FIG. [Figure 7] 2 is a view of the sheet wrapping body of FIG. 1 as seen from the left side. FIG. [Figure 8] 2 is a view of the sheet wrapping body of FIG. 1 as seen from the right side. FIG. [Figure 9] 1 is a diagram showing an example of a cross section of a base material of a packaging bag (first embodiment). FIG. [Figure 10] FIG. 10 is a diagram showing the state in which the packaging bag of the sheet packaging body is opened. [Figure 11] 10A and 10B are diagrams showing a state in which the sheet wrapping body is used. [Figure 12] FIG. 4 is a diagram showing an example of a cross section of a base material of a packaging bag (second embodiment). DETAILED DESCRIPTION OF THE INVENTION

[0021] <Package> An embodiment of the present invention will be described in detail with reference to the drawings. In each drawing, common parts are given the same reference numerals and their description may be omitted. Also, in each drawing, the scale of each part may differ from the actual scale. In each drawing, a three-dimensional Cartesian coordinate system with three axial directions (X direction, Y direction, and Z direction) is used, with the longitudinal direction of the packaging bag being the X direction, the width direction being the Y direction, and the height direction (vertical direction or thickness direction) being the Z direction.

[0022] Fig. 1 is a diagram showing a sheet packaging body in which a sheet is contained in a packaging bag of an embodiment. Fig. 2 is a diagram showing a sheet contained in the packaging bag of an embodiment. Figs. 3, 4, 5, 6, 7, and 8 are views of the sheet packaging body of Fig. 1 as seen from the top, bottom, front, back, left side, and right side, respectively.

[0023] As shown in FIG. 1, the sheet packaging body 100 has a packaging bag 10 and a sheet stack 20 (plurality of sheets S). The sheet packaging body 100 is an example of a sheet packaging body according to this embodiment. The packaging bag 10 is an example of a packaging bag constituting the sheet packaging body according to this embodiment. The sheet stack 20 is an example of a sheet contained in the packaging bag according to this embodiment.

[0024] As shown in Fig. 2, the packaging bag 10 contains a plurality of stacked sheets (or a plurality of sets of sheets S) (a sheet stack 20). The sheet stack 20 is contained in the packaging bag 10 so that the stacking direction (SD direction) of the sheets S is the height direction (Z direction). The sheet stack 20 is designed so that the sheets S can be pulled out one set at a time through an outlet (opening OP) (described later) formed in the packaging bag 10 (see Fig. 11).

[0025] The form of the sheet stack 20 is not particularly limited, and may be, for example, a stack of sheets S in a folded state, a stack of sheets S in a folded state and stacked alternately (a so-called pop-up type sheet stack), or a stack of multiple sheets S simply stacked.

[0026] The dimensions of the sheet S (sheet laminate 20) can be such that the length L2 in the longitudinal direction (X direction) of the packaging bag 10 is about 150 to 250 mm, the width W2 in the width direction (Y direction) perpendicular to the longitudinal direction (X direction) of the packaging bag 10 is about 70 to 150 mm, and the height H2 in the height direction (Z direction) is about 20 to 100 mm (see Figures 2 and 3). Such a tissue paper laminate can be produced, for example, by a rotary or multi-stand interfolder.

[0027] The form of the sheet S is not particularly limited, and it can be applied to, for example, sanitary thin papers such as paper towels, kitchen paper, tissue paper, toilet paper, etc. These sanitary thin papers also include sanitary thin papers containing moisturizing ingredients (for example, lotion tissue, etc.).

[0028] The use of the sheet S is not particularly limited, and it can be used for industrial, home, or portable purposes. Among these, household and portable paper towels are preferably used as the sheet in this embodiment.

[0029] The number of plies of the sheet S is not particularly limited, but can be one or more, and is preferably one or two (two layers stacked together). The shape of the sheet S is also not particularly limited, but it is preferable that the outline shape of the two-ply sheet when folded is quadrangular (rectangle, square, etc.).

[0030] The material of the sheet S is not particularly limited, but may be, for example, a sheet of paper, nonwoven fabric, or cloth, and is preferably paper (paper sheet). When the sheet S is a paper sheet, base paper containing pulp as the main raw material is used. The pulp composition may be any known composition for paper sheets. For example, the pulp content may be 50% by mass or more, preferably 90% by mass or more, and more preferably 100% by mass.

[0031] The pulp composition of the sheet S (paper sheet) is not particularly limited. For example, softwood pulp such as NBKP (softwood kraft pulp) or NUKP (softwood unbleached pulp) and hardwood pulp such as LBKP (hardwood kraft pulp) or LUKP (hardwood unbleached pulp) can be used in any ratio.

[0032] In the sheet S (paper sheet), the ratio of hardwood pulp to softwood pulp is not limited, but is preferably 10:90 to 80:20, and more preferably a pulp composition in which the ratio of softwood pulp to hardwood pulp is higher. Furthermore, recycled paper pulp may be used as the pulp contained in the sheet S (paper sheet).

[0033] The basis weight of the sheet S is not particularly limited, but in the case of paper, it is 5 g / m depending on the number of plies. 2 More than 80g / m 2 and preferably 10 g / m 2More than 60g / m 2 Less than 10 g / m, more preferably 2 More than 45g / m 2 In the case of nonwoven fabric, the density is 20 g / m 2 More than 100g / m 2 The following is desirable: Basis weight is measured in accordance with the provisions of JIS P 8124 (2011).

[0034] The thickness of the sheet S (paper sheet) is not particularly limited, and can be the paper thickness measured under the environment of JIS P 8111 (1998). For example, when the sheet S is paper, the paper thickness is 50 μm or more and 600 μm or less, preferably 60 μm or more and 500 μm or less, and more preferably 130 μm or more and 400 μm or less per two plies.

[0035] The sheet S (paper sheet) may be embossed by a known embossing method.

[0036] The shape of the packaging bag 10 is not particularly limited. In this embodiment, the packaging bag 10 has a top surface 11, a bottom surface 12, side surfaces 13 and 14, end surfaces 15 and 16. In the packaging bag 10, the top surface 11 and the bottom surface 12 face each other in the vertical direction (Z direction), the side surfaces 13 and 14 face each other in the width direction (Y direction), and the end surfaces 15 and 16 face each other in the longitudinal direction (X direction). In addition, the end surfaces 15 and 16 are continuous with all of the top surface 11, bottom surface 12, side surfaces 13, and side surfaces 14 (FIGS. 1, 3 to 8).

[0037] The dimensions of the packaging bag 10 are not particularly limited. For example, the length L1 of the packaging bag 10 in the longitudinal direction (X direction) can be about 150 to 250 mm, the width W1 in the width direction (Y direction) perpendicular to the longitudinal direction (X direction) of the packaging bag 10 can be about 70 to 150 mm, and the height H1 in the height direction (Z direction) can be about 20 to 100 mm (FIGS. 1 and 3). The dimensions of the packaging bag 10 refer to the dimensions when the sheet laminate 20 is housed in the packaging bag 10 (FIGS. 1 and 2).

[0038] The top surface 11 of the packaging bag 10, the top surface 11 side of the end surface 15, and the top surface 11 side of the end surface 16 are provided with take-out openings extending in the longitudinal direction (X direction) of the packaging bag 10. Specifically, the take-out openings are provided with a tear-open score line 30. The tear-open score line 30 is a score line in which cuts C and ties T (two cuts C and the uncut portion between the Cs) are alternately arranged, and when a tie T is broken, the cuts C on both sides become continuous cuts (Figs. 1, 3, 7, and 8).

[0039] In this embodiment, the tearing score line 30 forms a linear perforation M in which cuts C and ties T are alternately arranged (FIGS. 1, 3, 7, and 8). The ratio of ties T to cuts C in the tearing score line 30 (perforation) is arbitrary, but can be, for example, 1:1 to 1:7, preferably 1:1.3 to 1:5, and more preferably 1:1.5 to 1:3.

[0040] In the packaging bag 10 of this embodiment, tearing along the tearing score line 30 (perforation M) forms an opening (opening OP) on the top surface 11 of the packaging bag 10 through which the sheet S is pulled out (FIGS. 1 and 10).

[0041] Any method may be used to form the tear score line 30. For example, although not shown, the tear score line 30 can be formed by placing the substrate BS of the packaging bag 10 (described later) between the needle and the base, and inserting the tip of the needle into the receiving groove of the base.

[0042] The packaging bag 10 may have ventilation holes (not shown). The ventilation holes can function as air holes for the packaging bag 10. The positions of the ventilation holes are not particularly limited, and in this embodiment, ventilation holes can be provided on the side surfaces 13, 14, and end surfaces 15 and 16 of the packaging bag 10. The number of ventilation holes is not limited. The shape of the ventilation holes is not limited, and for example, they are circular in plan view. Furthermore, the dimensions of the ventilation holes are not limited, and for example, they have a diameter of about 2 mm.

[0043] The method for forming the ventilation hole is arbitrary, and for example, the ventilation hole can be formed by placing the base material BS of the packaging bag 10 between the needle and the base, and inserting the tip of the needle into the receiving groove of the base, in the same way as the above-mentioned tearing score line 30. When forming the ventilation hole, a base without a receiving groove may be used.

[0044] By providing such ventilation holes in the packaging bag 10, the packaging bag is less likely to burst when the sheet wrapping body 100 is stored or transported.

[0045] The packaging form of the packaging bag 10 is not particularly limited, and may be, for example, a pillow packaging bag in which the base material BS of the packaging bag 10 is processed into a cylindrical shape and the open end of the cylindrical base material BS is sealed, a caramel packaging bag in which both end portions of a cylindrical sheet for the packaging bag 10 are folded and sealed, or a combination of these. In the case of a pillow packaging bag, the cylindrical base material BS may be folded in a gusset shape.

[0046] In this embodiment, the packaging bag 10 is configured as a pillow packaging bag having at least one seal part. Specifically, seal parts (end seals) 40, 50 are formed on end surfaces 15, 16 of the packaging bag 10, and a seal part (bottom seal) 60 is formed on the bottom surface 12 of the packaging bag 10, and the sheet S (sheet stack 20) ​​is pillow packaged.

[0047] In the packaging bag 10 of this embodiment, the seal portions 40, 50, and 60 are heat-sealed. Here, heat-sealing refers to heating a part of the base material BS to weld parts of the packaging bag sheet together. Specifically, in a state where an inner layer (resin layer) 10B of the substrate BS, which will be described later, is placed inside the packaging bag 10, the seal portions 40, 50, 60 are heat-sealed.

[0048] In the packaging bag 10, the joining pitch of the seal portion 40, the joining pitch of the seal portion 50, and the joining pitch of the seal portion 60 are each preferably 0.5 mm or more and 2 mm or less, more preferably 0.8 mm or more and 1.8 mm or less, and even more preferably 1.0 mm or more and 1.5 mm or less.

[0049] Here, the joining pitch indicates the spacing in a predetermined direction (the width direction (Y direction) of the packaging bag 10 for the seal portions 40, 50, 60, and the longitudinal direction (X direction) of the packaging bag 10 for the seal portion 60) of the parts (not shown) that are convexly bonded when viewed from one side of the seal portions 40, 50, 60 (for example, the bottom surface 12 side of the packaging bag 10).

[0050] In this embodiment, as described above, by setting the joining pitch of the seal portions (seal portions 40, 50, 60) to 0.5 mm or more and 2 mm or less, the adhesive function of the inner layer (resin layer 10B) provided on the base layer (paper layer) 10A can be improved, and a packaging bag 10 (pillow packaging bag) with better sealing properties can be obtained.

[0051] The packaging bag 10 has a base material BS containing a paper component. Here, the paper component is made by agglutinating plant fibers (pulp). The pulp composition of the paper component is not limited, and for example, the ratio of hardwood pulp to softwood pulp is 0:100 to 70:30, and preferably the ratio of softwood pulp to hardwood pulp is higher. Furthermore, recycled paper pulp may be used as the pulp.

[0052] The substrate BS that constitutes the packaging bag 10 of the first embodiment is composed of a base layer 10A, an inner layer 10B, and an outer layer 10C. The substrate BS in the first embodiment has a three-layer structure in which the inner layer 10B and the outer layer 10C are laminated on each side of the paper layer 10A (FIG. 9).

[0053] The base layer 10A constitutes the base of the substrate BS and also constitutes a paper layer containing the above-mentioned paper components.

[0054] The material of the paper component contained in the base layer (paper layer) 10A is not particularly limited, but it can be made of, for example, kraft paper or rayon paper.

[0055] Here, kraft paper is paper made from kraft pulp. Rayon paper is made by blending rayon fiber, which is chemically synthesized from wood pulp, with kraft pulp. From the perspective of achieving both softness and strength in the packaging bag 10, it is preferable that the rayon fiber content of the rayon paper be 20% or less by mass.

[0056] The basis weight of the base layer (paper layer) 10A is not limited, but is preferably 10 g / m 2 More than 70g / m 2 or less, more preferably 15 g / m 2 More than 60g / m 2 More preferably, 20 g / m or less 2 More than 50g / m 2 The basis weight is measured in accordance with the provisions of JIS P 8124 (2011).

[0057] The thickness of the base layer (paper layer) 10A is not limited, but is preferably 20 μm to 300 μm, more preferably 30 μm to 200 μm, and even more preferably 40 μm to 180 μm, as measured in accordance with JIS P 8118 (2014).

[0058] The tensile strength of the base layer (paper layer) 10A is not limited, but is, for example, 500 cN / m or more and 20,000 cN / m or less, preferably 1,000 cN / m or more and 15,000 cN / m or less in the machine direction (machine direction or MD direction) of the fibers. 、 More preferably, it is 1500 cN / m or more and 12000 cN / m or less.

[0059] In addition, the fiber cross direction (direction perpendicular to the flow direction or CD direction) is 100 cN / m or more and 10,000 cN / m or less, preferably 300 cN / m or more and 5,000 cN / m or less 、The tensile strength is more preferably 500 cN / m or more and 2500 cN / m or less. The tensile strength is measured in accordance with the provisions of JIS P 8113 (2006).

[0060] The elongation of the base layer (paper layer) 10A is not limited, but is, for example, 0.5% to 30% in the machine direction (MD), preferably 1% to 25%, and more preferably 2% to 20%. The elongation in the cross direction (CD) is 0.5% to 20%, 1% to 10%, or 2% to 5%. The elongation is measured in accordance with JIS P 8113 (2006).

[0061] The tear strength of the base layer (paper layer) 10A is not limited, but is, for example, 50 mN or more and 500 mN or less, preferably 80 mN or more and 480 mN or less in the machine direction (MD direction) of the fibers. 、 More preferably, it is 100 mN or more and 450 mN or less.

[0062] In addition, the force in the cross direction (CD direction) of the fibers is 200 mN or more and 1000 mN or less, preferably 250 mN or more and 900 mN or less. 、 More preferably, it is 300 mN or more and 800 mN or less. The tear strength is measured in accordance with the provisions of JIS P 8116 (2000).

[0063] The inner layer 10B is provided on either side of the paper layer 10A and constitutes a resin layer containing a thermoplastic resin. The inner layer (resin layer) 10B constitutes the inner surface IS of the base material BS that is placed inside the packaging bag 10. The inner surface IS of the base material BS that is placed inside the packaging bag 10 constitutes the surface that comes into contact with the sheet S contained in the packaging bag 10.

[0064] The thermoplastic resin material contained in the inner layer (resin layer) 10B is not particularly limited, but is preferably low-density polyethylene, which may be either high-pressure low-density polyethylene (LDPE) or linear low-density polyethylene (L-LDPE).

[0065] The thickness of the inner layer (resin layer) 10B is not limited, but is preferably 5 μm to 40 μm, more preferably 7 μm to 35 μm, and even more preferably 9 μm to 30 μm. The paper thickness is measured in accordance with the provisions of JIS P 8118 (2014).

[0066] The thermoplastic resin contained in the inner layer (resin layer) 10B contains a slip agent. The slip agent is an agent that reduces the coefficient of friction of the surface (inner surface) of the inner layer 10B. In this embodiment, the slip agent is added to the thermoplastic resin contained in the inner layer (resin layer) 10B, but it may also be applied to the inner surface IS of the substrate BS.

[0067] The components of the slip agent are not particularly limited, but for example, ethylene homopolymer, fatty acid amide, vegetable oil, etc. can be used as the main component. The content of the slip agent relative to the thermoplastic resin is not particularly limited. In addition to the main component, the slip agent may also contain additives for purposes such as maintaining the stability of the slip agent.

[0068] The outer layer (printed layer) 10C is provided on either side of the paper layer 10A and constitutes a printed layer that is printed on the surface of the packaging bag. The outer layer (printed layer) 10C constitutes the outer surface OS of the base material BS that is placed on the outside of the packaging bag 10. The outer surface OS of the base material BS that is placed on the outside of the packaging bag 10 constitutes the surface on the side that does not come into contact with the sheet S contained in the packaging bag 10.

[0069] The outer layer (printed layer) 10C contains a gripping agent. Here, the gripping agent is an agent that increases the coefficient of friction of the surface (outer surface) of the outer layer 10C. In this embodiment, the gripping agent is applied to the outer surface OS of the base material BS, but may also be contained in the outer layer (printed layer) 10C.

[0070] The components of the gripping agent are not particularly limited, but for example, medium ink (synthetic resin), oil-based varnish, etc. can be used as the main component. The amount of gripping agent used relative to the outer layer (printed layer) 10C is not particularly limited. In addition to the main component, the gripping agent may also contain auxiliary agents and solvents depending on the purpose, such as maintaining the stability of the gripping agent.

[0071] In this embodiment, the ratio of the paper component in the packaging bag 10 (base material BS) is 50% or more.

[0072] The basis weight of the packaging bag 10 (substrate BS) is not limited, but is preferably 20 g / m 2 More than 100g / m 2 or less, more preferably 25 g / m 2 More than 70g / m 2 or less, more preferably 30 g / m 2 More than 60g / m 2 The basis weight is measured in accordance with the provisions of JIS P 8124 (2011).

[0073] The thickness (paper thickness) of the packaging bag 10 (substrate BS) is not limited, but is, for example, 25 μm to 350 μm, preferably 30 μm to 250 μm, and more preferably 45 μm to 200 μm. The thickness may be measured in accordance with the JIS P 8118 (2014) standard.

[0074] The tensile strength of the packaging bag 10 (substrate BS) is not limited, but is, for example, 1000 cN / m or more and 20000 cN / m or less, preferably 1500 cN / m or more and 18000 cN / m or less in the longitudinal direction (MD) of the fibers. 、 More preferably, it is 2000 cN / m or more and 15000 cN / m or less.

[0075] In addition, the fiber cross direction (CD direction) is 500 cN / m or more and 10,000 cN / m or less, preferably 1,000 cN / m or more and 8,000 cN / m or less 、The tensile strength is more preferably 1500 cN / m or more and 5000 cN / m or less. The tensile strength is measured in accordance with the provisions of JIS P 8113 (2006).

[0076] The elongation of the packaging bag 10 is not limited, but is, for example, 0.5% to 30% in the machine direction (MD) of the fibers, preferably 1% to 25% in the machine direction, and more preferably 2% to 20% in the cross direction (CD). The elongation is measured in accordance with JIS P 8113 (2006).

[0077] The tear strength of the packaging bag 10 is not limited, but is, for example, 50 mN or more and 500 mN or less, preferably 80 mN or more and 450 mN or less in the machine direction (MD direction) of the fibers. 、 More preferably, it is 100 mN or more and 400 mN or less.

[0078] In addition, the force in the cross direction (CD direction) of the fibers is 200 mN or more and 1000 mN or less, preferably 250 mN or more and 900 mN or less. 、 More preferably, it is 300 mN or more and 800 mN or less. The tear strength is measured in accordance with the provisions of JIS P 8116 (2000).

[0079] The Taber stiffness of the packaging bag 10 is not limited, but is, for example, 0.01 mN / m or more and 0.2 mN / m or less in the longitudinal direction of the fibers (MD direction), preferably 0.02 mN / m or more and 0.17 mN / m or less, and more preferably 0.03 mN / m or more and 0.15 mN / m or less.

[0080] The stiffness in the cross direction (CD) of the fibers is 0.001 mN / m or more and 0.1 mN / m or less, preferably 0.01 mN / m or more and 0.08 mN / m or less, and more preferably 0.02 mN / m or more and 0.07 mN / m or less. The Taber stiffness is measured in accordance with the provisions of JIS P 8125 (2000).

[0081] In the packaging bag 10 of this embodiment, a first static friction coefficient A occurs between the inner surface IS of the base material BS arranged inside the packaging bag 10 and the sheet S (sheet laminate 20). Also, a second static friction coefficient B occurs between the outer surface OS of the base material BS arranged outside the packaging bag 10 and artificial skin (not shown). The first static friction coefficient A is smaller than the second static friction coefficient B, and the first static friction coefficient A is 0.55 or less.

[0082] Here, the static friction coefficient is the ratio of the frictional force generated at the contact surface between two objects when there is no relative motion to the force acting perpendicular to the contact surface. The static friction coefficient is measured in accordance with the horizontal method specified in JIS P 8147 (2010). Furthermore, artificial skin refers to a molded product made of urethane elastomer that imitates human skin.

[0083] In this embodiment, the first static friction coefficient A on the inner surface IS side of the substrate BS containing a paper component is made smaller than the second static friction coefficient B on the outer surface OS side of the substrate BS, and the first static friction coefficient A is made 0.55 or less, so that the inner surface IS of the substrate BS becomes more slippery against the sheet S contained in the packaging bag 10.

[0084] Furthermore, since the second static friction coefficient B is greater than the first static friction coefficient A, the outer surface OS of the base material BS is less likely to slip against the artificial skin (not shown). Therefore, when a perforation M is provided in the paper packaging bag 10, the perforation M becomes easier to tear, making it easier to open even a paper packaging bag (FIG. 11).

[0085] In the packaging bag 10 of this embodiment, it is preferable that the ratio of the first static friction coefficient A to the second static friction coefficient B is 0.65 or less. Here, the ratio of the first static friction coefficient A to the second static friction coefficient B indicates the ratio of the first static friction coefficient A to the second static friction coefficient.

[0086] In this embodiment, by setting the ratio of the first static friction coefficient A to the second static friction coefficient B to be 0.65 or less, the difference between the friction coefficient of the inner surface IS of the substrate BS with respect to the sheet S contained in the packaging bag 10 and the friction coefficient of the outer surface OS of the substrate BS with respect to the artificial skin (not shown) becomes large. As a result, the perforations M provided in the paper packaging bag 10 become easier to tear, making it easier to open the packaging bag 10.

[0087] In the packaging bag 10 of this embodiment, the second static friction coefficient is preferably 1.1 or less. In a paper packaging bag, the difference between the first static friction coefficient and the second friction coefficient should be as large as possible in order to improve the ease of opening. On the other hand, if the second friction coefficient is too large relative to the first static friction coefficient, there is a risk that the perforations on the paper packaging bag will tear before the packaging bag is opened (for example, during the production, distribution, or storage of the sheet packaging body 100 using the packaging bag 10).

[0088] Therefore, in this embodiment, the second static friction coefficient B is adjusted to be 1.1 or less so that the outer surface OS of the base material BS does not become too slippery, thereby preventing unexpected tearing of the packaging bag 10 without reducing the ease of opening the packaging bag 10.

[0089] In the packaging bag 10 of this embodiment, the first static friction coefficient A corresponds to the static friction coefficient between the CD direction of the substrate BS and the MD direction of the sheet S. The second static friction coefficient corresponds to the static friction coefficient between the CD direction of the substrate BS and the artificial skin.

[0090] In this embodiment, the MD direction of the substrate BS corresponds to the longitudinal direction (X direction) of the packaging bag 10, and the CD direction of the substrate BS corresponds to the width direction (Y direction) of the packaging bag 10 (FIGS. 1, 3 to 8). Furthermore, the MD direction of the sheet S corresponds to the width direction (Y direction) of the packaging bag 10 or the sheet laminate 20, and the CD direction of the sheet S corresponds to the longitudinal direction (X direction) of the packaging bag 10 or the sheet laminate 20 (FIGS. 1 and 2).

[0091] In this embodiment, the static friction coefficient between the CD direction of the substrate BS and the MD direction of the sheet S is set to a first static friction coefficient A, which makes it easier for the CD direction of the substrate BS to slide relative to the MD direction of the sheet S. In addition, the static friction coefficient between the CD direction of the substrate BS and the artificial skin is set to a second static friction coefficient, which makes it harder for the artificial skin to slide relative to the CD direction of the substrate BS.

[0092] In this embodiment, when the sheet S is placed in the packaging bag 10 so that the MD direction of the sheet S is aligned with the CD direction of the base material BS and the perforation M is formed in the MD direction of the base material BS, if the surface of the packaging bag 10 on which the perforation M is formed (top surface 11) is pressed with the thumbs of both hands and the thumbs are moved apart in the CD direction of the base material BS, the perforation M will tear (FIGS. 1 and 10). At this time, the perforation tears easily with little force, making it even easier to open the packaging bag 10 (top surface 11).

[0093] As described above, in the packaging bag 10 of this embodiment, the top surface 11 of the packaging bag 10 is formed with the tearing score line 30 (perforation M) along the MD direction of the base material BS.

[0094] In this embodiment, by forming a tearing cut line 30 (perforation M) along the MD direction of the base material BS on the top surface 11 of the packaging bag 10, the packaging bag 10 can be easily opened by simply holding the top surface 11 of the packaging bag 10 with the thumbs of both hands and moving the thumbs apart in the CD direction of the base material BS, as the tearing cut line 30 (perforation M) will tear.

[0095] In this embodiment, the torn score line 30 (perforation M) can form a sheet removal opening (opening OP) formed on the top surface 11 of the packaging bag 10 (FIGS. 1 and 10). This makes it possible to remove the sheet S from the top surface 11 of the packaging bag 10.

[0096] In this embodiment, the tearing score line 30 (perforation M) is formed along the MD direction of the substrate BS and the CD direction of the sheet S, and the static friction coefficient is measured in the direction perpendicular to the direction in which the perforation M extends (the CD direction of the substrate BS and the MD direction of the sheet S), but the orientation of the sheet S and substrate BS for measuring the static friction coefficient is not limited. For example, the tearing score line 30 (perforation M) may be formed along the CD direction of the substrate BS and the MD direction of the sheet S, and the static friction coefficient may be measured in the direction perpendicular to the direction in which the perforation M extends (the MD direction of the substrate BS and the CD direction of the sheet S).

[0097] Furthermore, in the present embodiment, as described above, the case where the sheet S is contained in the packaging bag 10 so that the MD direction of the sheet S is aligned with the CD direction of the base material BS has been described, but the relationship between the MD direction of the sheet S and the CD direction of the base material BS is not limited. In other words, the direction in which the sheet S is contained in the packaging bag 10 is not limited. For example, the sheet S may be contained in the packaging bag 10 so that the MD direction of the sheet S is aligned with the MD direction of the base material BS.

[0098] Fig. 12 is a diagram showing a cross section of a base material of a packaging bag according to a second embodiment. In the second embodiment shown in Fig. 12, parts common to the first embodiment in Fig. 9 are given the same reference numerals as in Fig. 9, and description thereof will be omitted.

[0099] The substrate BS constituting the packaging bag 10 of the second embodiment is composed of a base layer 10A and an inner layer 10B. The substrate BS in the second embodiment has a two-layer structure in which the inner layer 10B is laminated on one side of the paper layer 10A (FIG. 12).

[0100] In the packaging bag 10 of the second embodiment, an outer layer 10C is not laminated on the other side of the paper layer 10A, but as in the first embodiment, the first static friction coefficient A generated between the inner surface IS of the base material BS arranged inside the packaging bag 10 and the sheet S (sheet laminate 20) is smaller than the second static friction coefficient B generated between the outer surface OS of the base material BS arranged outside the packaging bag 10 and the artificial skin (not shown), and the first static friction coefficient A is further set to 0.55 or less.

[0101] As a result, in the second embodiment, similarly to the first embodiment, the inner surface IS of the substrate BS becomes slippery relative to the sheet S contained in the packaging bag 10, and the outer surface OS of the substrate BS becomes less slippery relative to the artificial skin (not shown). Therefore, also in the second embodiment, when perforations M are provided in the paper packaging bag 10, the perforations M become easier to tear, making it easier to open even a paper packaging bag (FIG. 11).

[0102] Furthermore, in the packaging bag 10 of the second embodiment, the ratio of the first static friction coefficient A to the second static friction coefficient B is 0.65 or less. This makes it possible to increase the difference in the friction coefficient of the inner surface IS of the substrate BS against the sheet S contained in the packaging bag 10 and the friction coefficient of the outer surface OS of the substrate BS against the artificial skin (not shown). This makes it easier to tear the perforations M provided in the paper packaging bag 10, making it easier to open the packaging bag 10.

[0103] The sheet packaging body 100 of this embodiment can use the above-mentioned packaging bag 10. Specifically, the sheet packaging body 100 has a packaging bag 10 (the packaging bag of the first embodiment) and a sheet S contained in the packaging bag 10 (FIGS. 1 and 2).

[0104] The sheet packaging body 100 of this embodiment is configured as a sheet packaging body in which a sheet S is housed in the packaging bag 10 described above, and thus has the same effects as the packaging bag 10 described above. That is, in the sheet packaging body 100 of this embodiment, even if the packaging bag 10 constituting the sheet packaging body 100 is made of paper, the perforations M provided in the paper packaging bag 10 are easy to tear, making it easy to open even a paper packaging bag (FIG. 11).

[0105] As described above, in packaging bag 10 of this embodiment, inner layer (resin layer) 10B containing a thermoplastic resin is provided on either side of base layer (paper layer) 10A containing a paper component, which softens the texture of packaging bag 10. This reduces the stiffness of packaging bag 10 and provides conformability to packaging bag 10. Therefore, even if the material of the packaging bag is changed from resin to paper, it is possible to provide packaging bag 10 that is less likely to break during manufacturing or transportation.

[0106] Furthermore, in this embodiment, the packaging bag 10 has a base layer (paper layer) 10A and an inner layer (resin layer) 10B laminated thereon to give it conformability, and therefore has a tearing score line 30, making it easy to tear the tearing score line 30.

[0107] In addition, in this embodiment, the inner layer (resin layer) 10B provided on either side of the base layer (paper layer) 10A contains a thermoplastic resin, and by heating the inner layer (resin layer) 10B when sealing (or sealing) the packaging bag 10, the melted inner layer (resin layer) 10B can function as an adhesive (have an adhesive function), making it easy to seal the packaging bag 10.

[0108] Furthermore, in this embodiment, the ratio of paper components in the packaging bag 10 is 50% or more, so that the environmental load can be reduced.

[0109] In this embodiment, as described above, by setting the thickness of inner layer (resin layer) 10B to 5 μm or more and 40 μm or less, it becomes easier to maintain the ratio of paper components in the packaging bag at 50% or more. In addition, the adhesive function of inner layer (resin layer) 10B when sealing the packaging bag can be maintained while suppressing the stiffness of the packaging bag.

[0110] In this embodiment, as described above, by using low-density polyethylene as the thermoplastic resin contained in the inner layer (resin layer) 10B, the stiffness of the packaging bag 10 can be further reduced while improving the adhesive function of the inner layer (resin layer) 10B when sealing the packaging bag 10.

[0111] In this embodiment, as described above, packaging bag 10 is a pillow packaging bag, and the resin layers can be bonded together by heat-welding at least one seal portion with inner layer (resin layer) 10B disposed inside packaging bag 10. This makes it possible to effectively utilize the adhesive function of inner layer (resin layer) 10B, thereby obtaining packaging bag 10 with high sealing properties.

[0112] In this embodiment, by providing the packaging bag 10 with a tear score line 30, the packaging bag 10 can be opened simply by tearing the tear score line 30. The torn tear score line 30 can also form an access opening (opening OP) for the packaging bag 10. Furthermore, in this embodiment, the tear score line 30 is provided on the packaging bag 10, which has conformability due to the inner layer (resin layer) 10B being laminated on the paper layer 10A, so that the tear score line 30 can be easily torn. [Example]

[0113] The present invention will be described in more detail below with reference to examples. The examples and comparative examples were evaluated by the following tests.

[0114] [Test specimen] As a test sample, a sheet package 100 was prepared in which a plurality of sheets S (sheet stack 20) ​​were pillow-packaged in a paper packaging bag 10 (FIGS. 1 to 8).

[0115] The packaging bag 10 is made of a base material BS, which is composed of a base layer 10A, an inner layer 10B, and an outer layer 10C. The inner layer 10B is made of low-density polyethylene (PE). The outer layer 10C is a gravure-printed layer. A tear-open score line 30 (perforation M) is formed on the top surface 11 of the packaging bag 10, extending from the sealed portion 40 to the sealed portion 50 in the longitudinal direction (MD) of the packaging bag 10. The ratio of ties T to cuts C of the perforation M is 1:2 in the example and 1:5 in the comparative example.

[0116] The sheet stack 20 is a stack of sheets S folded and stacked together, and is composed of single (1-ply) paper towels (product name "Elveil Paper Towel Eco Dry (medium size)" manufactured by Daio Paper Corporation, 200 sets, height H1: 65 mm, length L1: 210 mm, width (depth) W1: 115 mm, basis weight 33 g / m 2 , paper thickness 180 μm) and double-type paper towels (product name "Elleair Paper Towel Smart Type Double (medium size)", manufactured by Daio Paper Corporation, 200 sets, height H1: 60 mm, length L1: 210 mm, width (depth) W1: 115 mm, basis weight 16 g / m 2 ×2) was used.

[0117] [Yonetsubo] The basis weight (grammage) of the base material (all layers) BS and base layer 10A of the packaging bag 10 in the test specimen (sheet packaging body 100) was measured in accordance with the provisions of JIS P 8124 (2011). The unit of basis weight is g / m 2 is.

[0118] [Paper thickness] The thickness (thickness) of the substrate (all layers) BS and base layer 10A of the packaging bag 10 in the test specimen (sheet packaging body 100) was measured using an ISO paper thickness meter (MEI-11, manufactured by CITIZEN Co., Ltd.) in accordance with the provisions of JIS P 8118 (2014). The unit of thickness is μm.

[0119] [Tensile strength] The tensile strength (mN) in the longitudinal direction (MD direction) and transverse direction (CD direction) of the substrate (all layers) BS and base layer 10A of the packaging bag 10 in the test specimen (sheet packaging body 100) was measured using a Tensilon universal testing machine (RTG-1210, manufactured by A&D Co., Ltd.) in accordance with the provisions of JIS P 8113 (2006).

[0120] [stretch] The elongation (%) in the longitudinal direction (MD direction) and transverse direction (CD direction) of the substrate (all layers) BS and base layer 10A of the packaging bag 10 in the test specimen (sheet packaging body 100) was measured using a Tensilon universal testing machine (RTG-1210, manufactured by A&D Co., Ltd.) in accordance with the provisions of JIS P 8113 (2006).

[0121] [Tear strength] The tear strength of the substrate (all layers) BS and base layer 10A of the packaging bag 10 in the test specimen (sheet packaging body 100) in the longitudinal direction (MD) and transverse direction (CD) of the fibers was measured using a tear strength tester (Elmendorf tear strength tester (digital display type) manufactured by Kumagai Riki Kogyo Co., Ltd.) in accordance with the provisions of JIS P 8116 (2000).

[0122] [Taber stiffness] The Taber stiffness of the substrate (all layers) BS of the packaging bag 10 in the test specimen (sheet packaging body 100) was measured in accordance with the provisions of JIS P 8125 (2000). A Taber stiffness tester (manufactured by Toyo Seiki Seisakusho, Ltd.) was used to measure the Taber stiffness.

[0123] [Static friction coefficient] The static friction coefficient was measured in accordance with the horizontal method of JIS P 8147 (2010). A load cell tensile tester (Shimadzu Corporation, AGS-500B) was used to measure the static friction coefficient.

[0124] Specifically, the static friction coefficient A1 between the CD direction of the inner surface IS (inner layer 10B) of the base material BS of the packaging bag 10 and the MD direction of the sheet S (web single) in the test specimen (sheet packaging body 100), the static friction coefficient A2 between the CD direction of the inner surface IS (inner layer 10B) of the base material BS of the packaging bag 10 and the MD direction of the sheet S (web double), and the static friction coefficient B between the CD direction of the outer surface OS (outer layer 10C) of the base material BS of the packaging bag 10 and artificial skin (Bioskin Plate, No. 132#BSC, manufactured by Viewlax, made of thermoplastic urethane elastomer) were measured.

[0125] In measuring the static friction coefficients A1 and A2, the substrate BS was fixed to the horizontal plate side of the friction tester so that the CD direction of the inner surface (inner layer 10B) of the substrate BS was facing outward, and the sheet S was fixed to the weight side of the friction tester so that the MD direction of the front surface of the sheet S was facing outward.

[0126] To measure the static friction coefficient B, the substrate BS was fixed to the horizontal plate of the friction tester so that the CD direction of the outer surface OS (outer layer 10C) of the substrate BS was facing outward. The artificial skin was cut from a size of 100 mm long x 100 mm wide x 5 mm thick to fit the weight side of the friction tester, and attached to the weight side of the friction tester so that the measurement surface was facing outward (non-glossy side).

[0127] If the dimensions of the test piece are insufficient, the back side (the side not being measured) of the test piece may be joined together using a paper-based sealant, etc. In this case, care should be taken to avoid wrinkles or sagging.

[0128] [Easy to open perforations] The ease of opening the perforation M (tear cut line 30) formed on the top surface 11 of the packaging bag 10 of the test specimen (sheet packaging body 100) was confirmed. The test was conducted for both cases where a single-type sheet S (web) was housed in the packaging bag 10 and where a double-type paper towel sheet was housed. The ease of opening the perforation in the sheet packaging body 100 was evaluated by having 10 users hold the surface (top surface 11) of the packaging bag 10 where the perforation M was formed with the thumbs of both hands and move their thumbs apart in the CD direction of the base material BS. If 0 to 3 people answered that it was difficult to open, the evaluation was rated as ◯ (good), and if 4 or more people answered that it was difficult to open, the evaluation was rated as × (poor). The evaluation criteria are as follows: A: Perforation M is easy to tear B: Perforation M can be torn C: The perforation cannot be torn, or it can be torn but is difficult to tear.

[0129] Examples and comparative examples will be described below.

[0130] [Example 1] When PE with added slip agent was used for the inner layer 10B of the base material BS of the packaging bag 10 and a gripping agent (varnish) was applied to the outer layer 10C, and the static friction coefficient A1 was 0.42, the static friction coefficient A2 was 0.38, and the static friction coefficient B was 0.96, the ease of opening the perforations was rated A for both single and double bags. The conditions of the packaging bag 10, the conditions of the sheet (web), and the evaluation results (static friction coefficient and ease of opening the perforations) are shown in Table 1.

[0131] [Example 2] The static friction coefficient A1 was 0.46, the static friction coefficient A2 was 0.45, and the static friction coefficient B was 0.95, but the evaluation was the same as in Example 1, and the ease of opening the perforation was rated B for both single and double. The conditions of the packaging bag 10, the conditions of the sheet (web), and the evaluation results are shown in Table 1.

[0132] [Example 3] The static friction coefficient A1 was 0.41, the static friction coefficient A2 was 0.37, and the static friction coefficient B was 0.8, and the evaluation was the same as in Example 1, and the ease of opening the perforation was rated A for both single and double. The conditions of the packaging bag 10, the conditions of the sheet (web), and the evaluation results are shown in Table 1.

[0133] [Comparative Example 1] When no slip agent was added to the PE used in the inner layer 10B of the base material BS of the packaging bag 10, no grip agent (varnish) was applied to the outer layer 10C, and the static friction coefficient A1 was 0.57, the static friction coefficient A2 was 0.69, and the static friction coefficient B was 1.2, the ease of opening the perforations was rated C for both single and double bags. The conditions of the packaging bag 10, the conditions of the sheet (web), and the evaluation results are shown in Table 1.

[0134] [Reference example 1] A sheet package was prepared in which multiple sheets S (sheet laminate 20) were pillow-packaged in a packaging bag made of resin film, and when the static friction coefficient A1 was 0.3, the static friction coefficient A2 was 0.27, and the static friction coefficient B was 1.14, the ease of opening the perforations was A for both single and double. The conditions of the packaging bag, the conditions of the sheet (web), and the evaluation results are shown in Table 1.

[0135] [Table 1]

[0136] As can be seen from Table 1, test specimens having a base material BS containing a paper component, in which the first static friction coefficient A (A1, A2) between the inner surface IS of the base material BS placed inside the packaging bag 10 and the sheet S is smaller than the second static friction coefficient B between the outer surface OS of the base material BS placed outside the packaging bag and the artificial skin, and in which the first static friction coefficient A is 0.55 or less, had good ease of opening the perforations (Examples 1 to 3).

[0137] In contrast, the test specimens with a first static friction coefficient exceeding 0.55 were poor in ease of opening the perforations (Comparative Example 1).

[0138] Although the embodiments of the present invention have been described above, the present invention is not limited to the specific embodiments, and various modifications and changes are possible within the scope of the invention described in the claims.

[0139] That is, in other words, an embodiment of the present invention is a packaging bag having a base material containing a paper component for containing a sheet, wherein the base material has a tearing score line formed thereon for removing at least the sheet from the packaging bag, and the coefficient of static friction between the outer surface of the base material and the fingers (or artificial skin) of a person tearing along the score line is greater than the coefficient of static friction between the inner surface of the base material and the sheet. Therefore, when tearing along the score line, the fingers do not slip, making it difficult to tear.

[0140] The substrate may have such a static friction coefficient over the entire surface of the packaging bag, or the substrate having such a static friction coefficient may be only the substrate on which the tearing score line is formed. It is also possible to make the static friction coefficient between a part of the substrate, which comes into contact with a human finger (or artificial skin) when tearing the tearing score line, larger than the static friction coefficient between the inner surface of the substrate and the sheet. [Explanation of symbols]

[0141] 100 sheet packaging 10 packaging bags BS base material IS inside OS external 10A base layer (paper layer) 10B Inner layer (resin layer) 10C Outer layer (printing layer) 11 Top 12 Bottom 13, 14 Side 15, 16 Wife face 20 Sheet stack S seat 30 Cut line for cleavage M perforation OP outlet (opening) 40, 50 Seal part (end seal) 60 Seal part (bottom seal) L1, L2 length W1, W2 width H1, H2 height

Claims

1. A packaging bag for containing a sheet, A substrate including a paper component, The tear strength in the lateral direction of the packaging bag is 300 mN or more and 800 mN or less, a first static friction coefficient between the sheet and an inner surface of the substrate disposed inside the packaging bag is smaller than a second static friction coefficient between the artificial skin and an outer surface of the substrate disposed outside the packaging bag; the first static friction coefficient is 0.55 or less; the substrate has a three-layer structure including a paper layer, an inner layer laminated on one surface of the paper layer to form the inner surface, and an outer layer laminated on the other surface to form the outer surface, the inner layer includes a slip agent; The outer layer contains a gripping agent. packaging bag.

2. a ratio of the first static friction coefficient to the second static friction coefficient is 0.65 or less; The packaging bag according to claim 1.

3. The second static friction coefficient is 1.1 or less. The packaging bag according to claim 1 or 2.

4. The first static friction coefficient is a static friction coefficient between the CD direction of the substrate and the MD direction of the sheet, The second static friction coefficient is the static friction coefficient between the substrate in the CD direction and the artificial skin. The packaging bag according to any one of claims 1 to 3.

5. A tearing score line is formed on the top surface of the packaging bag along the MD direction of the base material. The packaging bag according to claim 4.

6. The packaging bag according to any one of claims 1 to 5, A sheet contained in the packaging bag. Sheet packaging.

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