JP2023148575A - Packaging bag and sheet package - Google Patents

Abstract

To provide a paper packaging bag which is easy to open.SOLUTION: In a packaging bag that accommodates a sheet laminate in which multiple sheets are laminated, the density of the sheet laminate is 0.09 g/cm3 or more and 0.50 g/cm3 or less, the packaging bag is composed of a base material containing a paper component, the first static friction coefficient of the inner surface of the base material inside the packaging bag is 0.25 or more and 0.5 or less, the second static friction coefficient of the outer surface of the base material on the outside of the packaging bag is 0.3 or more and 0.65 or less, and the ratio of the first static friction coefficient to the second static friction coefficient is 0.5 or more and 0.9 or less.SELECTED DRAWING: Figure 1

Description

The present invention relates to a packaging bag and a sheet packaging body.

BACKGROUND ART Sheet packages containing sheets such as paper towels and tissue paper are distributed and used in a state in which a plurality of sheets are housed in a packaging bag made of resin film (for example, Patent Documents 1 and 2). In recent years, from the perspective of reducing environmental burdens such as global warming caused by _CO2 emissions and marine pollution caused by microplastics, the packaging bags used for sheet packaging have been changed from resin to paper. There is a growing movement to reduce the amount of carbon used.

Japanese Patent Application Publication No. 2008-183034 Japanese Patent Application Publication No. 2018-177364

However, paper packaging bags are less flexible than resin packaging bags, so when perforations are provided for opening, the perforations are difficult to tear and the bag is difficult to open.

An object of the present invention is to provide a paper packaging bag that is easy to open.

A first aspect of the present invention is a packaging bag that accommodates a sheet laminate in which a plurality of sheets are laminated, wherein the density of the sheet laminate is 0.09 g/cm 3 or more and 0.50 g/cm ³ or more. ³ or less, and the packaging bag is made of a base material containing a paper component, and the first static friction coefficient of the inner surface of the base material disposed inside the packaging bag is 0.25 or more and 0.5 or less. and the second static friction coefficient of the outer surface of the base material disposed on the outside of the packaging bag is 0.3 or more and 0.65 or less, and the ratio of the first static friction coefficient to the second static friction coefficient is To provide a packaging bag having a particle size of 0.5 or more and 0.9 or less.

In this specification, the paper component is made by sticking vegetable fibers together. The density of the sheet laminate is a density measured in accordance with the regulations of JIS P 8118 (2014). The coefficient of static friction indicates the ratio of the frictional force that occurs on the contact surfaces of two objects when they are not in relative motion to the force that acts perpendicularly to the contact surfaces.

The outside of the packaging bag indicates the side where the base material does not come into contact with the sheet accommodated in the packaging bag (that is, the side opposite to the side where the sheet is accommodated in the packaging bag or the side on which the outer layer of the base material is formed). The inside of the packaging bag refers to the side where the base material contacts the sheet accommodated in the packaging bag (that is, the side where the sheet is accommodated in the packaging bag or the side on which the inner layer of the base material is formed).

In the first aspect, for a sheet laminate having a density of 0.09 g/cm ³ or more and 0.50 g/cm ³ or less, the first static friction coefficient of the inner surface of the base material is 0.25 or more and 0.5 or less, and the base material The second static friction coefficient of the outer surface is 0.3 or more and 0.65 or less, and the ratio of the first static friction coefficient to the second static friction coefficient is 0.5 or more and 0.9 or less. As a result, a certain frictional force is generated on the inner surface of the base material constituting the packaging bag, and a larger frictional force is generated on the outer surface of the base material than the frictional force generated on the inner surface of the base material.

Therefore, the frictional force generated on the inner surface of the base material becomes relatively small on the inner surface of the base material and relatively large on the outer surface of the base material when the same sheet laminate is used as a reference. With such a configuration, fingers that touch the base material will not easily slip on the base material, so if a paper packaging bag is provided with perforations, the perforations will easily tear, and the paper packaging bag will Even if there is, it will be easier to open.

A second aspect of the present invention is that the base material includes a base layer containing the paper component, and an inner layer laminated on one side of the base layer and disposed inside the packaging bag, and the inner layer provides a packaging bag comprising a thermoplastic resin, the thermoplastic resin comprising a slip agent. As used herein, slip agents are additives that reduce the coefficient of friction.

In a second aspect, the base material of the packaging bag includes a base layer containing a paper component, and an inner layer laminated on one side of the base layer and disposed inside the packaging bag, and the inner layer contains a slip agent. By containing the thermoplastic resin, it is possible to reduce the coefficient of static friction between the inner surface of the base material and the sheet laminate. This makes the inner surface of the base material slippery against the sheet, so when a paper packaging bag is provided with perforations, the perforations tend to tear, and even paper packaging bags can be opened easily.

In a third aspect of the present invention, the base material includes a base layer containing the paper component, and an outer layer laminated on the other side of the base layer and disposed outside the packaging bag, and the outer layer provides a packaging bag containing a gripping agent. As used herein, gripping agents are additives that increase the coefficient of friction.

In a third aspect, the base material of the packaging bag includes a base layer containing a paper component, and an outer layer laminated on the other side of the base layer and disposed on the outside of the packaging bag, and the outer layer includes a grip agent. By doing so, it is possible to increase the frictional force generated between the outer layer of the base material and the fingers (hereinafter referred to as fingers) of the person who touches the outer layer of the base material. This makes it difficult for hands and fingers that touch the base material to slip on the base material, so if perforations are provided in a paper packaging bag, the perforations will be easier to tear, and even paper packaging bags will be easier to open. become.

A fourth aspect of the present invention provides a packaging bag, wherein the first static friction coefficient and the second static friction coefficient are static friction coefficients between the CD direction of the base material and the MD direction of the sheet.

In the fourth aspect, by setting the static friction coefficient between the CD direction of the inner surface of the base material and the MD direction of the sheet as the first static friction coefficient, the CD direction of the inner surface of the base material can easily slip with respect to the MD direction of the sheet. . Furthermore, by setting the static friction coefficient between the CD direction of the outer surface of the base material and the MD direction of the sheet as the second static friction coefficient, the CD direction of the base material outer surface can easily slip with respect to the MD direction of the sheet.

As a result, when the sheet is stored in a packaging bag so that the MD direction of the sheet is along the CD direction of the base material, and the perforation is formed in the MD direction of the base material, the surface on which the perforation is formed of the packaging bag can be held with both hands. The perforations are cleaved when each thumb is moved apart in the CD direction of the base material. At this time, the perforations can be easily torn with less force, making it easier to open the packaging bag.

A fifth aspect of the present invention provides a packaging bag, in which a tearing score line along the MD direction of the base material is formed on the top surface of the packaging bag. In this specification, a cleavage score line is a score line in which cuts and ties (the uncut portion between two cuts) are arranged alternately, and when a tie is broken, the cuts on both sides become continuous cuts (for example, perforations).

In the fifth aspect, by forming tearing lines along the MD direction of the base material on the top surface of the packaging bag, the top surface of the packaging bag is pressed with both thumbs, and each thumb is placed in the CD direction of the base material. Just by moving the packaging bag away, the tearing lines are torn, so the packaging bag can be easily opened. Further, the tearing cut line can constitute a sheet outlet formed on the top surface of the packaging bag.

A sixth aspect of the present invention provides a sheet package including the packaging bag according to any of the first to seventh aspects and a sheet accommodated in the packaging bag. In the sixth aspect, the same effect as the above-described packaging bag can be obtained by configuring a sheet package in which the sheet is accommodated in the above-described packaging bag. That is, according to the sixth aspect, even when the packaging bag constituting the sheet packaging is made of paper, it is possible to provide a sheet packaging in which the paper packaging bag is easy to open.

According to one aspect of the present invention, it is possible to provide a paper packaging bag that is easy to open.

FIG. 3 is a diagram showing a sheet packaging body in which sheets are housed in a packaging bag. It is a figure showing a sheet stored in a packaging bag. FIG. 2 is a view of the sheet package of FIG. 1 viewed from the top side. FIG. 2 is a view of the sheet package of FIG. 1 viewed from the bottom side. FIG. 2 is a front view of the sheet package shown in FIG. 1; FIG. 2 is a view of the sheet package of FIG. 1 viewed from the back side. FIG. 2 is a view of the sheet package of FIG. 1 viewed from the left side. FIG. 2 is a view of the sheet package of FIG. 1 viewed from the right side. It is a figure which shows an example of the cross section of the base material of a packaging bag. It is a figure which shows the state where the packaging bag of a sheet package was opened. It is a figure which shows the usage state of a sheet package.

<Package>
Embodiments of the present invention will be described in detail with reference to the drawings. In each figure, common parts may be given the same reference numerals and explanations may be omitted. Furthermore, in each figure, the scale of each part may differ from the actual scale. In each figure, a three-dimensional orthogonal coordinate system with three axes (X direction, Y direction, Z direction) is used. The longitudinal direction of the packaging bag is the X direction, the width direction is the Y direction, and the height direction (up and down direction or thickness direction) is defined as the Z direction.

FIG. 1 is a diagram showing a sheet packaging body in which sheets are housed in a packaging bag according to an embodiment. FIG. 2 is a diagram showing a sheet accommodated in the packaging bag of the embodiment. Figures 3, 4, 5, 6, 7, and 8 are views of the sheet packaging shown in Figure 1 from the top side, bottom side, front side, back side, left side, and right side, respectively. It is a diagram.

As shown in FIG. 1, the sheet package 100 includes a packaging bag 10 and a sheet laminate 20 (a plurality of sheets S). The sheet package 100 is an example of a sheet package according to this embodiment. Moreover, the packaging bag 10 is an example of a packaging bag that constitutes the sheet packaging body according to this embodiment. The sheet laminate 20 is an example of a sheet accommodated in the packaging bag according to this embodiment.

As shown in FIG. 2, the packaging bag 10 stores a plurality of stacked sheets S (or a plurality of sets) of stacked sheets S (sheet stack 20). The sheet stack 20 is housed in the packaging bag 10 such that the stacking direction (SD direction) of the sheets S is the height direction (Z direction). The sheet stack 20 is configured such that the sheets S can be pulled out one set at a time through an outlet (opening OP), which will be described later, formed in the packaging bag 10 (see FIG. 11).

The form of the sheet stack 20 is not particularly limited, and for example, the sheets S are folded and stacked, or the sheets S are folded and stacked alternately (a so-called pop-up sheet stack). (body), a sheet in which a plurality of sheets S are simply laminated, etc. can be adopted.

In addition, the dimensions of the sheet S (sheet laminate 20) include a length L2 in the longitudinal direction (X direction) of the packaging bag 10 of about 150 to 250 mm, and a width direction (L2) perpendicular to the longitudinal direction (X direction) of the packaging bag 10 ( The width W2 in the Y direction (Y direction) can be about 70 to 150 mm, and the height H2 in the height direction (Z direction) can be about 20 to 100 mm (see FIGS. 2 and 3). Such tissue paper laminates can be produced, for example, by rotary or multi-stand interfolders.

The density of the sheet laminate is 0.09 g/cm ³ or more and 0.50 g/cm ³ or less, preferably 0.13 g/cm ³ or more and 0.40 g/cm ³ or less, more preferably 0.15 g/cm ³ It is above 0.30 g/cm ³ or below. The density of the sheet laminate is measured in accordance with the regulations of JIS P 8118 (2014).

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

Further, the use of the sheet S is not particularly limited, and can be applied to any of industrial, household, and portable uses. Note that, among these sheets, household and portable paper towels are preferably used as the sheet in this embodiment.

The number of plies of the sheet S is not particularly limited, but it can be one or more, and preferably one or two plies (two ply). Further, the shape of the sheet S is not particularly limited, but it is preferable that the two-ply sheet has a rectangular outline (rectangular, square, etc.) in a folded state, for example.

The material of the sheet S is not particularly limited, but for example, a sheet of paper, nonwoven fabric, or cloth can be used, and paper (paper sheet) is preferable. Note that when the sheet S is a paper sheet, a base paper whose main raw material is pulp is used. As the pulp composition, a known composition for paper sheets can be used. For example, the blending ratio of pulp can be 50% by mass or more, preferably 90% by mass or more, and more preferably 100% by mass.

Further, the pulp composition in 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. I can do it.

In addition, 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 the ratio of softwood pulp to hardwood pulp is higher. Pulp composition. Furthermore, waste paper pulp may be used as the pulp contained in the sheet S (paper sheet).

The basis weight of the sheet S is not particularly limited, but depending on the number of plies, in the case of paper, it is 5 g/m ² or more and 80 g/m ² or less, preferably 10 g/m ² or more and 60 g/m ² or less, more preferably is 10 g/m ² or more and 45 g/m ² or less. Furthermore, in the case of non-woven fabric, it is desirable that it is 20 g/m ² or more and 100 g/m ² or less. Note that the basis weight is measured in accordance with the regulations of JIS P 8124 (2011).

Further, the thickness of the sheet S (paper sheet) is not particularly limited, and a paper thickness measured under the environment of JIS P 8111 (1998) can be adopted. 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 2 plies.

Further, the sheet S (paper sheet) may be embossed. Such embossing can be performed by a known embossing method.

The form of the packaging bag 10 is not particularly limited. In this embodiment, it has a top surface 11, a bottom surface 12, side surfaces 13, side surfaces 14, a gable surface 15, and a gable surface 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 faces 13 and 14 face each other in the width direction (Y direction), and the end faces 15 and 16 face each other in the longitudinal direction. (X direction). Furthermore, the end surfaces 15 and 16 are continuous with the top surface 11, the bottom surface 12, the side surfaces 13, and the side surfaces 14 (FIGS. 1, 3 to 8).

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) is about 150 to 250 mm, and the width W1 of the packaging bag 10 in the width direction (Y direction) perpendicular to the longitudinal direction (X direction) is about 70 to 150 mm. The height H1 in the height direction (Z direction) can be about 20 to 100 mm (FIGS. 1 and 3). Note that the dimensions of the packaging bag 10 indicate the dimensions when the sheet laminate 20 is accommodated in the packaging bag 10 (FIGS. 1 and 2).

Output ports extending in the longitudinal direction (X direction) of the packaging bag 10 are formed on the top surface 11 of the packaging bag 10, on the top surface 11 side of the end surface 15, and on the top surface 11 side of the end surface 16. Specifically, a cleavage cut line 30 is formed at the outlet. The tearing score line 30 is a score line where cuts C and ties T (the two cuts C and the uncut part between C) are arranged alternately, and when the tie T is broken, the cuts C on both sides become continuous cuts. (Fig. 1, Fig. 3, Fig. 7, Fig. 8).

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

In the packaging bag 10 of the present embodiment, when the tearing cut line 30 (perforation M) is torn, an outlet (opening OP) from which the sheet S is pulled out is formed on the top surface 11 of the packaging bag 10 ( Figure 1, Figure 10).

Note that the method for producing the cleavage score line 30 is arbitrary. For example, although not shown, the base material BS of the packaging bag 10, which will be described later, is placed between the needle part and the base part, and the tip of the needle part is pierced toward the receiving groove of the base part, so that the tearing score line 30 is can be formed.

The packaging bag 10 may be provided with ventilation holes (not shown). The ventilation holes can function as air holes in the packaging bag 10. The position of the ventilation hole is not particularly limited, and in this embodiment, the ventilation hole can be provided on the side surface 13, the side surface 14, and the end surfaces 15 and 16 of the packaging bag 10. The number of ventilation holes is not limited. Moreover, the shape of the ventilation hole is not limited, and is, for example, circular in plan view. Further, the dimensions of the vent holes are not limited, and may be, for example, approximately 2 mm in diameter.

Note that the method for creating the ventilation hole is arbitrary. For example, similarly to the above-mentioned tearing score line 30, the base material BS of the packaging bag 10 is placed between the needle part and the base part, and the tip of the needle part is By pricking toward the receiving groove of the base, a ventilation hole can be formed. In addition, when forming a ventilation hole, you may use the thing in which the receiving groove is not provided in the base part.

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

The packaging form of the packaging bag 10 is not particularly limited, and for example, the base material BS of the packaging bag 10 may be processed into a cylindrical shape, and the open end of the cylindrical base material BS may be sealed (sealed). A pillow packaging bag), a cylindrical packaging bag 10 sheet with both ends folded and sealed (caramel packaging bag), or a combination of these can be used. In addition, in the case of a pillow packaging bag, the cylindrical base material BS may be folded into a gusset shape.

In this embodiment, the packaging bag 10 is configured as a pillow packaging bag having at least one seal portion. Specifically, seal portions (end seals) 40 and 50 are formed on the end surfaces 15 and 16 of the packaging bag 10, a seal portion (bottom seal) 60 is formed on the bottom surface 12 of the packaging bag 10, and the sheet S ( The sheet laminate 20) is pillow wrapped.

In the packaging bag 10 of this embodiment, the seal parts 40, 50, and 60 are heat-welded. Here, thermal welding refers to heating a part of the base material BS to weld parts of the packaging bag sheet together, specifically, the inner layer (resin layer) 10B of the base material BS described later is The seal portions 40, 50, and 60 are heat-welded while being placed inside the bag 10.

In the packaging bag 10, the bonding pitch of the seal portions 40, the bonding pitch of the seal portions 50, and the bonding pitch of the seal portions 60 are each preferably 0.5 mm or more and 2 mm or less, and more preferably 0.8 mm or more and 1.8 mm or less. , more preferably 1.0 mm or more and 1.5 mm or less.

Here, the bonding pitch is defined as the predetermined direction ( For the seal portions 40 and 50, the distance is shown in the width direction (Y direction) of the packaging bag 10, and for the seal portion 60, the distance is shown in the longitudinal direction (X direction) of the packaging bag 10.

In this embodiment, as described above, by setting the bonding pitch of the seal parts (seal parts 40, 50, 60) to 0.5 mm or more and 2 mm or less, the inner layer ( The adhesive function of the resin layer 10B) can be improved, and a packaging bag 10 (pillow packaging bag) with higher sealing properties can be obtained.

The packaging bag 10 is made of a base material BS containing a paper component. Here, the paper component is a material (pulp) made of stuck vegetable fibers. The pulp composition in the paper component is not limited, and for example, the ratio of hardwood pulp to softwood pulp is 0:100 to 70:30, preferably a pulp composition in which the ratio of softwood pulp to hardwood pulp is higher. Furthermore, waste paper pulp may be used as the pulp.

The base material BS constituting 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 base material BS in the first embodiment has a three-layer structure in which an inner layer 10B and an outer layer 10C are laminated on each surface of a paper layer 10A (FIG. 9).

The base layer 10A constitutes the base of the base material BS. Further, the base layer 10A constitutes a paper layer containing the above-mentioned paper components. That is, the base material BS includes a base layer 10A containing a paper component.

The material of the paper component included in the base layer (paper layer) 10A is not particularly limited, but may be made of, for example, kraft paper or rayon paper.

Here, kraft paper is paper made from kraft pulp. Rayon paper is made by blending rayon fibers, which are chemically synthesized from wood pulp and the like, with kraft pulp. In addition, from the viewpoint of achieving both softness and strength of the packaging bag 10, the rayon paper preferably has a blending ratio of rayon fibers of 20% or less by mass ratio.

The basis weight of the base layer (paper layer) 10A is not limited, but is preferably 10 g/m ² or more and 70 g/m 2 or ^less , more preferably 15 g/m ² or more and 60 g/m ² or less, and even more preferably 20 g/m 2 or less. ² or more and 50 g/m ² or less. Note that the basis weight is measured in accordance with the regulations of JIS P 8124 (2011).

The thickness of the base layer (paper layer) 10A is not limited, but is, for example, preferably 20 μm or more and 300 μm or less, more preferably 30 μm or more and 200 μm or less, and still more preferably 40 μm or more and 180 μm or less. Note that the thickness is measured in accordance with the regulations of JIS P 8118 (2014).

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 longitudinal direction of the fibers (machine direction or MD direction). is 1500 cN/m or more and 12000 cN/m or less.

In addition, in the lateral direction of the fiber (direction perpendicular to the flow direction or CD direction), it is 100 cN/m or more and 10,000 cN/m or less, preferably 300 cN/m or more and 7,000 cN/m or less, more preferably 500 cN/m or more and 4,000 cN/m or less. . Note that the tensile strength is measured in accordance with the regulations of JIS P 8113 (2006).

The elongation of the base layer (paper layer) 10A is not limited, but is, for example, 0.5% or more and 30% or less, preferably 1% or more and 25% or less, more preferably 2% or more in the longitudinal direction (MD direction) of the fibers. It is 20% or less. Further, the content in the transverse direction (CD direction) of the fibers is 0.5% or more and 20% or less, 1% or more and 10% or less, and 2% or more and 5% or less. Note that elongation is measured in accordance with the provisions of JIS P 8113 (2006).

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 in the longitudinal direction (MD direction) of the fibers, preferably 80 mN or more and 480 mN or less, more preferably 100 mN or more and 450 mN or less.

Further, the force in the lateral direction (CD direction) of the fiber is 50 mN or more and 1000 mN or less, preferably 80 mN or more and 900 mN or less, more preferably 100 mN or more and 800 mN or less. Note that tear strength is measured in accordance with the provisions of JIS P 8116 (2000).

The inner layer 10B is laminated on one side of the base layer (paper layer) 10A, and constitutes a resin layer containing a thermoplastic resin. The inner layer (resin layer) 10B is arranged inside the packaging bag 10. Here, the inside of the packaging bag 10 is the side where the base material BS is in contact with the sheet S accommodated in the packaging bag 10 (that is, the side where the sheet S is accommodated in the packaging bag 10 or the inner layer 10B of the base material BS is formed). side).

The inner layer 10B includes an inner surface IS of the base material BS arranged inside the packaging bag 10 (the side where the sheet S is accommodated in the packaging bag 10). Note that the inner surface IS of the base material BS disposed inside the packaging bag 10 is the surface on which the base material BS contacts the sheet S accommodated in the packaging bag 10 (i.e., the surface on which the inner layer 10B of the base material BS is formed). side or the surface of the base material BS opposite to the side on which the outer layer is formed).

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

The thickness of the inner layer (resin layer) 10B is not limited, but is preferably 5 μm or more and 40 μm or less, more preferably 7 μm or more and 35 μm or less, and even more preferably 9 μm or more and 30 μm or less. Note that the paper thickness is measured in accordance with the regulations of JIS P 8118 (2014).

The thermoplastic resin contained in the inner layer (resin layer) 10B contains a slip agent. Here, the slip agent is an additive that reduces the coefficient of friction on the surface (inner surface) of the inner layer 10B. In this embodiment, the slip agent is added to the thermoplastic resin included in the inner layer (resin layer) 10B, but it may be coated on the inner surface IS of the base material BS.

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. Note that the content of the slip agent in the thermoplastic resin is not particularly limited. In addition to the main components, the slip agent may contain additives depending on the purpose, such as maintaining the stability of the slip agent.

In the present embodiment, the base material BS of the packaging bag 10 includes a base layer 10A containing a paper component, and an inner layer 10B laminated on one surface of the base layer 10A and disposed inside the packaging bag 10. Since 10B contains a thermoplastic resin containing a slip agent, the frictional force between the base material BS and the sheet S can be reduced. As a result, the base material BS becomes easily slippery on the sheet S. Therefore, when the paper packaging bag 10 is provided with perforations M, the perforations M are easily torn, and the paper packaging bag 10 is It also makes opening easier (Figures 1 and 10).

The outer layer (printing layer) 10C is provided on the other surface of the paper layer 10A, and constitutes a printing layer printed on the surface of the packaging bag. The outer layer (printed layer) 10C is arranged on the outside of the packaging bag 10. Here, the outside of the packaging bag 10 is the side where the base material BS is not in contact with the sheet S accommodated in the packaging bag 10 (that is, the side opposite to the side where the sheet S is accommodated in the packaging bag 10 or the side of the base material BS (The side on which the inner layer 10B is formed) is shown.

The outer layer (printed layer) 10C constitutes the outer surface OS of the base material BS arranged on the outer side of the packaging bag 10 (the side opposite to the side where the sheet S is accommodated in the packaging bag 10). Note that the outer surface OS of the base material BS disposed outside the packaging bag 10 is the surface on the side not in contact with the sheet S accommodated in the packaging bag 10 (that is, the surface on the side on which the outer layer 10C of the base material BS is formed). or the surface of the base material BS opposite to the side on which the inner layer 10B is formed).

The outer layer (printed layer) 10C contains a grip agent. Here, the grip agent is an additive that increases the coefficient of friction of the surface (outer surface) of the outer layer 10C. Although the grip agent is coated on the outer surface OS of the base material BS in this embodiment, it may be included in the outer layer (printed layer) 10C.

The components of the grip agent are not particularly limited, but for example, medium ink (synthetic resin), oil-based varnish, etc. can be used as the main component. Note that the amount of grip agent used for 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.

In this embodiment, the base material BS of the packaging bag 10 includes a base layer 10A containing a paper component, and an outer layer 10C laminated on the other surface of the base layer 10A and disposed on the outside of the packaging bag 10. By including the gripping agent in 10C, it is possible to increase the frictional force generated between the outer layer 10C of the base material BS and the fingers (hereinafter referred to as fingers) of a person who touches the outer layer 10C of the base material BS. This makes it difficult for fingers that touch the base material BS to slip on the base material BS, so when the sheet S is provided in the paper packaging bag 10, the sheet S is easily torn, and the paper packaging bag 10 However, it is easier to open the package (Fig. 1, Fig. 10).

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

The basis weight of the packaging bag 10 (base material BS) is not limited, but is preferably 20 g/m ² or more and 100 g/m ² or less, more preferably 25 g/m ² or more and 70 g/m ² or less, and even more preferably 30 g/m 2 or more. / ^m2 or more and 60g/ ^m2 or less. Note that the basis weight is measured in accordance with the regulations of JIS P 8124 (2011).

The thickness (paper thickness) of the packaging bag 10 (base material BS) is not limited, but is, for example, 25 μm or more and 350 μm or less, preferably 30 μm or more and 250 μm or less, and more preferably 45 μm or more and 200 μm or less. Note that the thickness can be measured in accordance with the regulations of JIS P 8118 (2014).

The tensile strength of the packaging bag 10 (base material 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 direction) of the fibers. It is 2000 cN/m or more and 15000 cN/m or less.

Further, in the lateral direction (CD direction) of the fibers, it 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, more preferably 1,500 cN/m or more and 5,000 cN/m or less. Note that the tensile strength is measured in accordance with the regulations of JIS P 8113 (2006).

The elongation of the packaging bag 10 (base material BS) is not limited, but is, for example, 0.5% or more and 30% or less, preferably 1% or more and 25% or less, more preferably 2% in the longitudinal direction (MD direction) of the fibers. % or more and 20% or less. In addition, the content in the transverse direction (CD direction) of the fibers is 0.5% or more and 20% or less, 1% or more and 10% or less, and 1.5% or more and 5% or less. Note that elongation is measured in accordance with the provisions of JIS P 8113 (2006).

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

Further, the force in the lateral direction (CD direction) of the fiber is 200 mN or more and 1000 mN or less, preferably 250 mN or more and 900 mN or less, more preferably 300 mN or more and 800 mN or less. Note that tear strength is measured in accordance with the provisions of JIS P 8116 (2000).

The Taber stiffness of the packaging bag 10 (base material BS) is not limited, but is, for example, 0.01 mN/m or more and 0.2 mN/m or less, preferably 0.02 mN/m or more and 0.02 mN/m or less in the longitudinal direction (MD direction) of the fibers. .17 or less, more preferably 0.03 mN/m or more and 0.15 mN/m or less.

In addition, in the lateral direction (CD direction) of the fiber, it is 0.001 mN/m or more and 0.2 mN/m or less, preferably 0.01 mN/m or more and 0.15 mN/m or less, and more preferably 0.02 mN/m or more and 0. It is 13 mN/m or less. Note that Taber stiffness is measured in accordance with the regulations of JIS P 8125 (2000).

In the packaging bag 10 of this embodiment, the inner surface IS of the base material BS disposed inside the packaging bag 10 (the inner surface IS on the side where the inner layer 10B of the base material BS is formed) has the first static friction coefficient A. The first static friction coefficient A is 0.25 or more and 0.5 or less, preferably 0.27 or more and 0.48 or less, and more preferably 0.3 or more and 0.45 or less.

In this specification, the coefficient of static friction indicates the ratio of the frictional force generated on the contact surfaces of two objects without relative motion to the force acting perpendicularly to the contact surfaces. The static friction coefficient is measured in accordance with the provisions of JIS P 8147 (2010) horizontal method.

The first static friction coefficient A can be defined as the static friction coefficient A1 occurring between the inner surface IS of the base material BS and the sheet S (paper towel with a basis weight of 33 g/m ² ). In this case, the static friction coefficient A1 is 0.3 or more and 0.5 or less, preferably 0.33 or more and 0.48 or less, and more preferably 0.35 or more and 0.45 or less.

Further, the first static friction coefficient A can be defined as the static friction coefficient A2 occurring between the inner surface IS of the base material BS and the aluminum foil (thickness: 20 μm). In this case, the static friction coefficient A2 is 0.25 or more and 0.5 or less, preferably 0.27 or more and 0.48 or less, and more preferably 0.3 or more and 0.45 or less.

Further, the outer surface OS of the base material BS disposed on the outside of the packaging bag 10 (the outer surface OS of the side on which the outer layer 10C of the base material BS is formed) has a second static friction coefficient B. The second static friction coefficient B is 0.3 or more and 0.65 or less, preferably 0.35 or more and 0.63 or less, and more preferably 0.4 or more and 0.6 or less.

The second static friction coefficient B can be defined as the static friction coefficient B1 occurring between the outer surface OS of the base material BS and the sheet S (paper towel with a basis weight of 33 g/m ² ). In this case, the static friction coefficient B1 is 0.5 or more and 0.65 or less, preferably 0.52 or more and 0.6 or less, and more preferably 0.54 or more and 0.57 or less.

Further, the second static friction coefficient B can be defined as the static friction coefficient B2 occurring between the outer surface OS of the base material BS and the aluminum foil (thickness: 20 μm). In this case, the static friction coefficient B2 is 0.3 or more and 0.54 or less, preferably 0.35 or more and 0.53 or less, and more preferably 0.4 or more and 0.52 or less.

In the packaging bag 10 of this embodiment, the ratio of the first static friction coefficient A to the second static friction coefficient B is 0.5 or more and 0.9 or less, preferably 0.55 or more and 0.89 or less, and more preferably 0. .6 or more and 0.87 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.

Note that when the first static friction coefficient A is the static friction coefficient A1 and the second static friction coefficient B is the static friction coefficient B1, the ratio between the static friction coefficient A1 and the static friction coefficient B1 is 0.6 or more and 0.85 or less, preferably 0. It is .65 or more and 0.83 or less, more preferably 0.7 or more and 0.8 or less.

Further, when the first static friction coefficient A is the static friction coefficient A2 and the second static friction coefficient B is the static friction coefficient B2, the ratio between the static friction coefficient A2 and the static friction coefficient B2 is 0.5 or more and 0.9 or less, preferably 0. It is .55 or more and 0.89 or less, more preferably 0.6 or more and 0.87 or less.

The base material BS having such a coefficient of static friction may be formed over the entire surface of the packaging bag 10, or may be formed only on the surface where the perforations M are formed (for example, the top surface 11 of the packaging bag). Good too.

In this embodiment, as described above, the ^first static friction coefficient A of the inner surface IS of the base material is 0.25 or more ^and 0. .5 or less, the second static friction coefficient B of the outer surface OS of the base material is 0.3 or more and 0.65 or less, and the ratio of the first static friction coefficient A to the second static friction coefficient is 0.5 or more and 0.9 or less. There is. As a result, a certain frictional force is generated on the inner surface IS of the base material BS constituting the packaging bag 10, and a larger frictional force is generated on the outer surface OS of the base material BS than the frictional force generated on the inner surface IS of the base material BS.

Therefore, the frictional force generated on the inner surface IS of the base material BS is relatively small on the inner surface IS of the base material and relatively large on the outer surface OS of the base material when the same sheet laminate 20 is used as a reference (FIG. 9). . In such a configuration, the fingers that touch the base material BS are difficult to slip on the base material BS, so when the paper packaging bag 10 is provided with perforations M, the perforations M are likely to tear, and the paper Even if the packaging bag 10 is made of

In addition, in this embodiment, the first static friction coefficient A of the inner surface IS of the base material BS disposed inside the packaging bag 10 is 0.25 or more and 0.5 or less, so that the base material BS containing the paper component is The inner surface IS is in a slippery state with respect to the sheet S. Therefore, the perforations M provided in the paper packaging bag 10 are more easily torn, and the packaging bag 10 can be opened even more easily (FIGS. 1 and 10).

Further, by setting the ratio of the first static friction coefficient A to the second static friction coefficient B to be 0.5 or more and 0.9 or less, the friction coefficient of the inner surface IS side of the base material BS with respect to the sheet S accommodated in the packaging bag 10 The difference between this and the friction coefficient on the outer surface OS side of the base material BS becomes large. Therefore, the perforations M provided in the paper packaging bag 10 are more easily torn, so the packaging bag 10 can be opened more easily.

In addition, in a paper packaging bag, the difference between the first static friction coefficient A and the second static friction coefficient B is preferably as large as possible in order to improve unsealability. On the other hand, if the second static friction coefficient B becomes too large with respect to the first static friction coefficient A, the perforations M provided in the paper packaging bag 10 may be damaged before the packaging bag 10 is opened (for example, when the packaging bag 10 is not used). There is a risk that the sheet packaging body 100 may be ruptured during manufacturing, distribution, storage, etc.).

Therefore, in this embodiment, the second static friction coefficient B is adjusted to be 0.3 or more and 0.65 or less so that the outer surface OS of the base material BS does not become too slippery. Therefore, unexpected tearing of the packaging bag 10 can be prevented without reducing the unsealability of the packaging bag 10.

In the packaging bag 10 of this embodiment, the first static friction coefficient A and the second static friction coefficient B correspond to the static friction coefficient between the CD direction of the base material BS and the MD direction of the sheet S.

In addition, in this embodiment, the MD direction of the base material BS corresponds to the longitudinal direction (X direction) of the packaging bag 10, and the CD direction of the base material BS corresponds to the width direction (Y direction) of the packaging bag 10. (Figure 1, Figure 3 to Figure 8). Further, 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. (Fig. 1, Fig. 2).

In this embodiment, by setting the static friction coefficient between the CD direction of the inner surface IS of the base material and the MD direction of the sheet as the first static friction coefficient, the CD direction of the inner surface of the base material can easily slip with respect to the MD direction of the sheet. . Further, by setting the static friction coefficient between the CD direction of the base material outer surface OS and the sheet MD direction as the second static friction coefficient, the CD direction of the base material outer surface OS becomes easier to slide with respect to the sheet MD direction.

As a result, when the sheet S is housed in the packaging bag 10 so that the MD direction of the sheet is along the CD direction of the base material, and the perforation M is formed in the MD direction of the base material, the perforation M of the packaging bag is formed. When pressing the surface with both thumbs and moving the thumbs apart in the CD direction of the base material, the perforation M is cleaved. At this time, the perforations M can be easily torn with a small amount of force, making it easier to open the packaging bag 10.

In the packaging bag 10 of this embodiment, as described above, the tearing score line 30 (perforation M) along the MD direction of the base material BS is formed on the top surface 11 of the packaging bag 10.

In this embodiment, by forming tearing cut lines 30 (perforations M) along the MD direction of the base material BS on the top surface 11 of the packaging bag 10, the top surface 11 of the packaging bag 10 is pressed with the thumbs of both hands. , simply by moving the thumbs apart in the CD direction of the base material BS, the tearing score line 30 (perforation line M) is torn, so the packaging bag 10 can be easily opened.

Furthermore, in the present embodiment, the tearing cut line 30 (perforation M) can constitute an outlet (opening OP) for the sheet S formed on the top surface 11 of the packaging bag 10 (see FIG. 1, Figure 10). Therefore, the sheet S can be taken out from the top surface 11 of the packaging bag 10.

In addition, in this embodiment, the tearing score line 30 (perforation M) is formed along the MD direction of the base material BS and the CD direction of the sheet S, and the perforation line 30 is formed along the MD direction of the base material BS and the CD direction of the sheet S. Although the static friction coefficient is measured in the CD direction and the MD direction of the sheet S, the orientation of the sheet S and the base material BS in which the static friction coefficient is measured is not limited. For example, the tearing score line 30 (perforation M) is formed along the CD direction of the base material BS and the MD direction of the sheet S, and the direction perpendicular to the direction in which the perforation M extends (the MD direction of the base material BS and the sheet S The static friction coefficient may be measured in the CD direction).

Furthermore, in the present embodiment, as described above, the sheet S is housed in the packaging bag 10 such that the MD direction of the sheet S is along the CD direction of the base material BS. The relationship is not limited to the CD direction of the material BS. That is, the direction in which the sheet S is accommodated in the packaging bag 10 is not limited. For example, the sheet S may be accommodated in the packaging bag 10 such that the MD direction of the sheet S is along the MD direction of the base material BS.

The above-described packaging bag 10 can be used for the sheet packaging body 100 of this embodiment. Specifically, the sheet package 100 includes a packaging bag (packaging bag of the first embodiment) 10 and a sheet S accommodated in the packaging bag 10 (FIGS. 1 and 2).

The sheet packaging body 100 of this embodiment is configured as a sheet packaging body in which the sheet S is housed in the packaging bag 10 described above, and thus the same effects as the packaging bag 10 described above can be obtained. That is, in the sheet packaging body 100 of this embodiment, even when 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 likely to tear, and the paper Even if the packaging bag is made of

In the packaging bag 10 of this embodiment, as described above, the inner layer (resin layer) 10B containing a thermoplastic resin is provided on one side of the base layer (paper layer) 10A containing a paper component, so that the packaging bag The texture of 10 becomes softer. Thereby, the stiff feeling of the packaging bag 10 can be suppressed, and the packaging bag 10 can be given conformability. Therefore, even if the material of the packaging bag is changed from resin to paper, it is possible to provide the packaging bag 10 that is difficult to break during manufacturing or transportation.

Furthermore, in this embodiment, the packaging bag 10 is provided with followability by laminating the inner layer (resin layer) 10B on the base layer (paper layer) 10A, and therefore the tearing score line 30 is provided. The cut line 30 can be easily cleaved.

Further, in this embodiment, since the inner layer (resin layer) 10B provided on one side of the base layer (paper layer) 10A contains a thermoplastic resin, when sealing (or sealing) the packaging bag 10, the inner layer By heating the (resin layer) 10B, the melted inner layer (resin layer) 10B can function as an adhesive (has an adhesive function), so the packaging bag 10 can be easily sealed.

Furthermore, in this embodiment, since the ratio of the paper component in the packaging bag 10 is 50% or more, the environmental load can be suppressed.

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

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 suppressed, and the The adhesive function of the inner layer (resin layer) 10B can be improved.

In this embodiment, as described above, the packaging bag 10 is a pillow packaging bag, and at least one seal portion is thermally welded with the inner layer (resin layer) 10B disposed inside the packaging bag 10. This allows the resin layers to be bonded together. Thereby, the adhesive function of the inner layer (resin layer) 10B can be effectively utilized, so that a packaging bag 10 with high sealability can be obtained.

Hereinafter, the present invention will be further described in detail using Examples. Evaluation of Examples and Comparative Examples was performed by the following tests.

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

The packaging bag 10 was composed of a base material BS, and the base material BS was composed of a base layer 10A, an inner layer 10B, and an outer layer 10C (FIG. 9). The material of the inner layer 10B was low density polyethylene (PE). The outer layer 10C was a gravure printed layer. A tearing score line 30 (perforation M) extending from the seal part 40 through the top surface 11 to the seal part 50 in the longitudinal direction (MD direction) of the packaging bag 10 is formed on the top surface 11 of the packaging bag 10. The ratio of tie T to cut C of perforation M was 1:2 in the examples and comparative examples.

The sheet laminate 20 of the sheet S is a paper towel 1 (product name: "Eleair Paper Towel Double (medium size)", manufactured by Daio Paper Co., Ltd., double (2 ply), 200 sets (400 sheets), height H1: 70 mm, length Size L1: 210mm, width (depth) W1: 115mm, basis weight 23g/m ² , density 0.293g/cm ³ ), paper towel 2 (product name: "Elver Paper Towel Eco Dry (medium size)", manufactured by Daio Paper Co., Ltd. Single (1 ply), 200 sheets, height H1: 67mm, length L1: 210mm, width (depth) W1: 115mm, basis weight 33g/m ² , density 0.194g/cm ³ ), and tissue paper (product Name: "Elleair i:na tissue soft pack", manufactured by Daio Paper Co., Ltd., double (2 ply), 150 sets (300 sheets), height H1: 43mm, length L1: 181mm, width (depth) W1 : 103 mm, basis weight 10.7 g/m ² , density 0.171 g/cm ³ ).

[Yonetsubo]
The basis weight (basis weight) 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 tsubo is g/ ^m2 .

[Paper thickness]
The paper thickness (thickness) 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 using an ISO paper thickness meter (CITIZEN Co., Ltd.) in accordance with the provisions of JIS P 8118 (2014). The measurement was carried out using MEI-11) manufactured by Kogyo Co., Ltd. The unit of thickness is μm.

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

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

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

[Taber stiffness]
The Taber stiffness of the base material (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 Co., Ltd.) was used to measure the Taber stiffness.

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

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, and the CD of the inner surface IS (inner layer 10B) of the base material BS The static friction coefficient A2 between the direction and the MD direction of the sheet S was measured.

Note that the sheet S is a paper towel with a basis weight of 33 g/m ² (product name: "Elvere Paper Towel Eco Dry Single (medium size)", manufactured by Daio Paper Co., Ltd., 200 sheets, height H1: 65 mm, length L1: 210 mm, Width (depth) W1: 115 mm) was used.

Furthermore, the coefficient of static friction B1 between the CD direction of the outer surface OS (outer layer 10C) of the base material BS of the packaging bag 10 and the MD direction of the sheet S, and the coefficient of static friction B1 of the outer surface OS (outer layer 10C) of the base material BS of the packaging bag 10 The static friction coefficient B2 between the CD direction and the glossy surface of the aluminum foil (also referred to as aluminum foil) was measured.

In addition, the aluminum foil used was an aluminum foil (manufactured by UACJ Foil Co., Ltd., MyFoil (registered trademark)) having a size of 30 cm in width, 7 m in length, and 20 μm in thickness.

To measure the static friction coefficients A1, A2, B1, and B2, the base material BS was fixed on the horizontal plate side of the friction tester so that the CD direction of the inner surface (inner layer 10B) of the base material BS was on the front side. The sheet S was fixed to the weight side so that the MD direction of the front side of the sheet S was the front side.

Furthermore, the ratio between the static friction coefficient A1 and the static friction coefficient B1 and the ratio between the static friction coefficient A2 and the static friction coefficient B2 were calculated.

[Easy to open perforations]
The ease of opening the perforation M (cutting line 30) formed on the top surface 11 of the packaging bag 10 in the test specimen (sheet packaging 100) was confirmed. The test was conducted for cases in which a single type paper towel sheet was housed in the packaging bag 10 as the sheet S (web) and a case in which a double type paper towel sheet was housed in the packaging bag 10. To evaluate the ease of opening perforations in the sheet packaging body 100, 10 users pressed the surface (top surface 11) on which the perforations M of the packaging bag 10 were formed with their thumbs, and pressed the surface of the packaging bag 10 in the CD direction of the base material BS. When the thumbs are moved apart, 5 (good) if 0 to 2 people answered that it was difficult to open, 4 if 3 to 4 people, 3, 7 if 5 to 6 people answered that it was difficult to open. The rating was 2 for ~8 people, and 1 for 9 to 10 people. The evaluation criteria are as follows.
5: Very easy to open 4: Easy to open 3: Can be opened 2: Can be opened but difficult to open 1: Cannot be opened

Examples and comparative examples will be described below.

[Example 1]
The inner layer 10B of the base material BS of the packaging bag 10 is made of PE with a slip agent added, and the outer layer 10C is coated with a grip agent (varnish), and the static friction coefficient A1 is 0.44, the static friction coefficient A2 is 0.31, and the static friction is The coefficient B1 was 0.56, the static friction coefficient B2 was 0.42, the ratio between static friction coefficient A1 and static friction coefficient B1 was 0.786, and the ratio between static friction coefficient A2 and static friction coefficient B2 was 0.738. Table 1 shows the conditions of the packaging bag 10, the conditions of the sheet (web), and the evaluation results.

[Example 2]
Static friction coefficient A1 is 0.45, static friction coefficient A2 is 0.44, static friction coefficient B1 is 0.56, static friction coefficient B2 is 0.51, ratio of static friction coefficient A1 to static friction coefficient B1 is 0.804, static friction coefficient A2 A test specimen was prepared and evaluated in the same manner as in Example 1, except that the ratio between B2 and the static friction coefficient B2 was 0.863. Table 1 shows the conditions of the packaging bag 10, the conditions of the sheet (web), and the evaluation results.

[Example 3]
Friction coefficient A1 is 0.38, static friction coefficient A2 is 0.31, static friction coefficient B1 is 0.55, static friction coefficient B2 is 0.51, ratio of static friction coefficient A1 to static friction coefficient B1 is 0.691, static friction coefficient A2 A test specimen was prepared and evaluated in the same manner as in Example 1, except that the ratio between B2 and the static friction coefficient B2 was 0.608. Table 1 shows the conditions of the packaging bag 10, the conditions of the sheet (web), and the evaluation results.

[Comparative example 1]
Friction coefficient A1 is 0.53, static friction coefficient A2 is 0.47, static friction coefficient B1 is 0.51, static friction coefficient B2 is 0.50, ratio of static friction coefficient A1 to static friction coefficient B1 is 1.039, static friction coefficient A2 A test specimen was prepared and evaluated in the same manner as in Example 1, except that the ratio between B2 and the static friction coefficient B2 was 0.940. Table 1 shows the conditions of the packaging bag 10, the conditions of the sheet (web), and the evaluation results.

From Table 1, the density of the sheet laminate is 0.171 to 0.293 g/cm ³ or less, the static friction coefficient A1 is 0.38 to 0.45, the static friction coefficient A2 is 0.31 to 0.44, and the static friction coefficient is 0.38 to 0.45. B1 is 0.55 to 0.56, the static friction coefficient B2 is 0.42 to 0.51, the ratio between the static friction coefficient A1 and the static friction coefficient B1 is 0.691 to 0.804, and the ratio between the static friction coefficient A2 and the static friction coefficient B2 is Test specimens with a ratio of 0.608 to 0.863 had good perforation ease (Examples 1 to 3).

On the other hand, the coefficient of friction A1 is 0.53, the coefficient of static friction A2 is 0.47, the coefficient of static friction B1 is 0.51, the coefficient of static friction B2 is 0.50, and the ratio of the coefficient of static friction A1 to the coefficient of static friction B1 is 1. 039, and the ratio of the static friction coefficient A2 to the static friction coefficient B2 was 0.940, and the test specimen had poor perforation ease (Comparative Example 1).

Although the embodiments of the present invention have been described above, the present invention is not limited to specific embodiments, and various modifications and changes can be made within the scope of the invention described in the claims. .

100 sheet packaging body 10 packaging bag BS base material IS inner surface OS outer surface 10A base layer (paper layer)
10B Inner layer (resin layer)
10C outer layer (printing layer)
11 Top surface 12 Bottom surface 13, 14 Side surfaces 15, 16 End surface 20 Sheet laminate S Sheet 30 Cutting line 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 (6)

A packaging bag for accommodating a sheet laminate in which a plurality of sheets are laminated,
The density of the sheet laminate is 0.09 g/cm ³ or more and 0.50 g/cm ³ or less,
The packaging bag is composed of a base material containing a paper component,
The first static friction coefficient of the inner surface of the base material disposed inside the packaging bag is 0.25 or more and 0.5 or less,
The second static friction coefficient of the outer surface of the base material disposed on the outside of the packaging bag is 0.3 or more and 0.65 or less,
The ratio of the first static friction coefficient to the second static friction coefficient is 0.5 or more and 0.9 or less,
packaging bag. The base material is
a base layer containing the paper component;
an inner layer laminated on one side of the base layer and disposed inside the packaging bag,
The inner layer includes a thermoplastic resin,
The thermoplastic resin contains a slip agent.
The packaging bag according to claim 1. The base material is
a base layer containing the paper component;
an outer layer laminated on the other side of the base layer and arranged on the outside of the packaging bag,
the outer layer contains a gripping agent;
The packaging bag according to claim 1 or 2. The first static friction coefficient and the second static friction coefficient are static friction coefficients between the CD direction of the base material and the MD direction of the sheet,
The packaging bag according to any one of claims 1 to 3. A tearing cut line along the MD direction of the base material is formed on the top surface of the packaging bag.
The packaging bag according to any one of claims 1 to 4. The packaging bag according to any one of claims 1 to 5,
a sheet accommodated in the packaging bag;
Sheet packaging.

Images