JP2021084406A - Packaging material and package using the same - Google Patents

Abstract

To provide a packaging material which facilitates tear in opening, and a package using the same.SOLUTION: There is provided a packaging material in which a polyolefin resin layer is laminated on one surface of spun-bonded non-woven fabric composed of a sheath core type composite long fiber whose sheath part is a composed of a polyolefin-based polymer and whose core part is composed of a thermoplastic polymer having a higher melting point than a melting point of the polyolefin-based polymer of the sheath part, the spun-bonded non-woven fabric has a thermal compression part, the thermal compression part is obtained by mutually bonding the core parts in a fiber form is maintained by re-solidifying after melting or softening the polyolefin-based polymer of the sheath part of the sheath core type composite long fiber, and the continuous recessed thermal compression part surrounds a non-thermal compression part. There is provided a package in which the packaging materials overlap so that the polyolefin film sides face each other, a machine direction of at least the spun-bonded non-woven fabric is heat-sealed, and a notch notched in the machine direction is provided in the vicinity of the heat-sealed part.SELECTED DRAWING: Figure 3

Description

The present invention relates to a packaging material, particularly a packaging material that is easily torn and a packaging material using the same.

Various materials are used as the packaging material, and a non-woven fabric may be used for the purpose of responding to changes in the shape of the packaged article and allowing the contents to be transparent. The non-woven fabric can be heat-sealed and sealed to wrap the article, and is therefore suitable for enclosing a soft article. However, the non-woven fabric has a drawback that it is difficult to tear when opened. Further, since the non-woven fabric is a fiber in the heat seal, it is difficult to perform uniform thermocompression bonding.

In Japanese Patent Application Laid-Open No. 2016-203594 (Patent Document 1), a laminate having an unstretched layer composed of a resin composition containing a polyolefin-based resin and a polyolefin-polystyrene-based elastomer is stretched on one side of a polyolefin-based non-woven fabric. Composite sheets are disclosed. This composite sheet is also difficult to tear and open.

Japanese Unexamined Patent Publication No. 2016-203594

The present invention provides a packaging material that can be easily torn when opened and a packaging body using the same.

That is, the present invention provides the following aspects:
[1]
A polyolefin resin on one side of a spunbonded non-woven fabric made of a core-sheath type composite long fiber composed of a thermoplastic polymer whose sheath is a polyolefin polymer and whose core is higher than the melting point of the polyolefin polymer in the sheath. The layers are laminated, and the spunbonded non-woven fabric has a heat-bonded portion, and the heat-bonded portion is formed into a fiber morphology by resolidification after melting or softening of the polyolefin-based polymer in the sheath portion of the core-sheath type composite long fiber. A packaging material in which the maintained cores are bonded to each other, and a continuous concave heat-bonded portion surrounds the non-heat-bonded portion.
[2]
The packaging material according to [1], wherein the thermoplastic polymer of the core portion is a polyester-based polymer, and the melting point of the core portion is higher than the melting point of the polyolefin-based polymer constituting the sheath portion by 30 ° C. or more.
[3]
The packaging material according to [1] or [2], wherein the melting point of the polyolefin resin layer is substantially the same as the melting point of the polyolefin constituting the sheath component.
[4]
The packaging material according to any one of [1] to [3], wherein the spunbonded non-woven fabric has a basis weight of 20 to 40 g / m ^2.
[5]
The packaging material according to any one of [1] to [4], wherein the core-sheath type composite long fiber has a single fiber fineness of 1 to 10 decitex.
[6]
A packaging body obtained by stacking the packaging materials according to claim 1 so that the polyolefin resin layer sides face each other and heat-sealing at least the mechanical direction of the spunbonded non-woven fabric, and cutting in the mechanical direction in the vicinity of the heat-sealed portion. A packaging body with a sewn notch.
[7]
The package according to [6], wherein the spunbonded non-woven fabric is heat-sealed not only in the mechanical direction but also in the transverse direction.
[8]
The package according to [6] or [7], which includes an article to be packaged.

The packaging material of the present invention is a span made of a core-sheath type composite long fiber composed of a thermoplastic polymer having a sheath portion of a polyolefin-based polymer and a core portion having a melting point higher than the melting point of the polyolefin-based polymer of the sheath portion. A polyolefin resin layer is laminated on one side of the bonded non-woven fabric, and the spun-bonded non-woven fabric has a heat-bonding portion, and the heat-bonding portion is a melting of the polyolefin-based polymer in the sheath portion of the core-sheath type composite long fiber. Alternatively, the core portions that maintain the fiber morphology are adhered to each other by solidification after softening, and a continuous concave heat-bonded portion surrounds the non-thermal-bonded portion. When a notch is made in the machine direction at the end of the packaging material of the present invention, it can be easily torn in the machine direction from the cut portion, and even though the packaging material uses a non-woven fabric, it is easy to open. .. Moreover, even though it is easy to open, it will not be unnecessarily torn and damage the packaged article.

The packaging material of the present invention can be encapsulated by stacking the polyolefin resin layers so as to face each other, inserting the article to be packaged into the packaging material, and heat-sealing all the openings. Heat sealing is performed in the mechanical direction (MD direction) of the spunbonded non-woven fabric and the transverse direction (CD direction) perpendicular to this, and when a notch cut in the MD direction is provided at the end of the package, the notch is formed. It can be torn with a moderate force at the starting point. In the present invention, the packaging material refers to a laminate of a spunbonded non-woven fabric and a polyolefin resin layer, and the packaging material is used to wrap an article, heat-seal the open end portion thereof, and cut in the MD direction. A package with a notch is called a package.

Although it is not known why the tearability is improved, when the polyolefin resin layer is laminated on the non-woven fabric, the sheath component of the core-sheath type composite long fiber constituting the non-woven fabric is composed of the polyolefin-based polymer, so that the layers are laminated. Occasionally, the polyolefin is melted and integrated, but the core portion of the core-sheath type composite long fiber remains fibrous, and the fiber is oriented in the mechanical direction, so it is considered that tearing is facilitated in that direction. Further, the packaging material of the present invention is a spunbonded non-woven fabric, and a part thereof is thermocompression bonded to melt or soften the polyolefin-based polymer in the sheath portion of the core-sheath type composite long fiber, and the core portion has a fiber form. Since it is maintained, it is considered that the fibers are oriented in the mechanical direction, which makes the tearing easier. However, this theory alone is not sufficient to explain why when a notch in the MD direction is inserted, the notch can be torn in the MD direction with just the right force. Therefore, it is not limited to this theory, and other theories need to be considered.

FIG. 1 is a diagram schematically showing a non-thermocompression bonding portion and a thermocompression bonding portion of the spunbonded nonwoven fabric used for the packaging material of the present invention. FIG. 2 is a diagram schematically showing another aspect of the non-thermocompression bonding portion and the thermocompression bonding portion of the spunbonded nonwoven fabric used for the packaging material of the present invention. FIG. 3 is a schematic view showing a bag-shaped state of the packaging material of the present invention.

The packaging material of the present invention is a span composed of a core-sheath type composite long fiber composed of a polyolefin-based polymer in the sheath and a thermoplastic polymer having a core having a melting point higher than the melting point of the polyolefin-based polymer in the sheath. A polyolefin resin layer is laminated on a bonded non-woven fabric.

The combination of the polyolefin-based polymer in the sheath and the thermoplastic polymer with a high melting point in the core includes a polyolefin-based polymer (sheath) / polyester-based polymer (core) and a polyolefin-based polymer (sheath) / polyamide. Examples thereof include a based polymer (core) and a polyethylene-based polymer (sheath) / polypropylene-based polymer (core). When a polyester-based polymer is selected as the core portion, the mechanical strength becomes high. Further, the combination of the polyethylene-based polymer (sheath) / polypropylene-based polymer is preferable because it has high compatibility with each other and is easy to handle. In the present invention, a core-sheath type composite long fiber composed of a polyolefin-based polymer (sheath) / polyester-based polymer (core) can be preferably used.

Hereinafter, a spunbonded non-woven fabric made of a core-sheath type composite long fiber composed of a polyolefin-based polymer (sheath) / polyester-based polymer (core) will be described.

<Spanbond non-woven fabric>
The polyester-based polymer constituting the core includes aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, naphthalin-2,6 dicarboxylic acid, or aliphatic dicarboxylic acids such as adipic acid and sebacic acid as acid components. There are homopolyesters or copolymerized polyesters synthesized from these esters and diol compounds such as ethylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, cyclohexane-1,4-dimethanol as alcohol components. , Paraoxybenzoic acid, 5-sodium sulfoisophthalic acid, polyalkylene glycol, pentaerythritol, bisphenyl A and the like may be added or copolymerized to the polyester.

Examples of the polyolefin-based polymer constituting the sheath include aliphatic α-monoolephine having 2 to 16 carbon atoms, such as ethylene, propylene, 1-butene, 1-pentene, 3-methyl1-butene, and 1-hexene. , 1-octene, 1-dodecene, 1-octadecene homo-olefin or copolymerized polyolefin and the like. The aliphatic α-monoolephine is an olefin and / or a small amount (up to about 10% by weight of the weight of the polymer) of other ethylene unsaturated monomers such as butadiene, isoprene, pentadiene-1,3, styrene, α-. It may be copolymerized with a similar ethylene-based unsaturated monomer such as methylstyrene. Particularly in the case of polyethylene, those copolymerized with propylene, butene-1, hexene-1, octene-1 or a similar higher α-olefin up to about 10% by weight of the polymer weight is preferable.

In addition, polyester-based polymers and polyolefin-based polymers include matting agents, pigments, flameproofing agents, deodorants, antistatic agents, antioxidants, ultraviolet absorbers, as long as they do not impair the object of the present invention. Any additives such as antibacterial agents may be added.

As the combination of the core portion and the sheath portion, a polymer having a melting point difference of 30 ° C. or higher, preferably 50 ° C. or higher is selected from the above polymers. That is, the one in which the melting point of the polyolefin-based polymer constituting the sheath portion is 30 ° C. or higher, preferably 50 ° C. or higher lower than the melting point of the polyester-based polymer constituting the core portion is selected. The long fibers constituting the non-woven fabric are integrated by having a thermocompression bonding portion to maintain the form as a non-woven fabric. The thermocompression bonding portion is formed by thermocompression bonding. In the thermocompression bonding portion, the sheath portion is melted or softened and then resolidified to contribute to adhesion, but the core portion is affected by heat. Maintains fiber morphology rather than receiving and melting. In this way, in the heat-bonded portion, the sheath portion is melted or softened, while the core portion is provided with a difference of 30 ° C. or higher, more preferably 50 ° C. or higher in order to maintain the fiber morphology. At the time of thermal embossing, the core portion is not affected by heat, and the sheath portion is surely melted or softened so that the thermal bonding portion can be fixed by thermal bonding.

The core-sheath composite ratio (mass ratio) of the core-sheath type composite long fiber is preferably core / sheath = 80/20 to 50/50. By making the ratio of the core portion equal to or higher than that of the sheath portion, the mechanical properties are excellent and the practical strength can be maintained. If the ratio of the core portion exceeds 80% by mass, the ratio of the sheath portion as an adhesive component becomes small, so that the adhesive strength at the thermocompression bonding portion tends to decrease, and further, the tearability in the MD direction is easy. The upper limit of the ratio of the core portion is preferably 80% by mass because it tends to be difficult to contribute to.

The single fiber fineness of the core-sheath type composite long fiber is preferably 1 to 10 decitex, and the basis weight of the non-woven fabric is preferably 20 to 40 g / m ² . By setting the single fiber fineness to 1 decitex or more, the strength of the non-woven fabric can be maintained, and the role of protecting the packaged article can be satisfactorily played. On the other hand, when the value is 10 decitex or less, the non-woven fabric is less likely to have a basis weight and uniform strength can be maintained. By setting the basis weight to 20 g / m ² or more, practical strength can be secured, while by setting the ^{basis weight to 40 g / m 2} or less, it is possible to have a slightly transparent feeling, so that it is packaged. When the article is printed, it can be visually recognized from the outside, and it is possible to perform confirmation work on the article.

The non-woven fabric is a spunbonded non-woven fabric and is manufactured by the spunbond method. For example, long fiber bundles are drawn while being drawn using air pressure, electrostatically opened by a method such as corona discharge, deposited on a moving collection surface to form a web, and then the fibers are integrated. To obtain a non-woven fabric. Since many fibers (core-sheath type composite long fibers) in the non-woven fabric are mainly oriented in the mechanical direction (MD direction), the spunbonded non-woven fabric is easily torn in the MD direction. In the present invention, taking advantage of the fact that the spunbonded non-woven fabric tends to be torn in the MD direction, and by passing a non-woven fabric that has been made into a web by deposition through a thermal embossing device, the non-woven fabric is subjected to thermocompression bonding. However, it is considered that the tearing is likely to occur by forming a specific thermocompression bonding portion.

The non-woven fabric is subjected to thermocompression bonding using a thermal embossing roll to form a thermocompression bonding portion, and the thermocompression bonding portion is such that a continuous thermocompression bonding portion surrounds a non-thermocompression bonding portion. Is preferably formed. FIG. 1 illustrates that the non-thermocompression bonding portion has an elliptical shape and is surrounded by continuous thermocompression bonding portions, but the shape is not limited to this. For example, as shown in FIG. 2, the non-thermocompression bonding portion may have a square shape and may be surrounded by a thermocompression bonding portion having a girder shape. The thermocompression bonding portion is a state in which the polyolefin-based polymer in the sheath portion of the core-sheath type composite long fiber is melted or softened and then resolidified, and the core portions that maintain the fiber morphology without being affected by heat are adhered to each other. The non-thermocompression bonding portion is in a state in which both the core portion and the sheath portion maintain the form of the core-sheath type composite long fiber without being affected by heat. The continuous thermocompression bonding part also improves the morphological stability of the obtained non-woven fabric, and if the non-thermocompression bonding part is surrounded by the continuous thermocompression bonding part, the morphological stability is good and tearing is easy. A non-woven fabric can be obtained.

The shape of the thermocompression bonding portion may be appropriately designed, and various shapes such as a circle, an ellipse, and a polygon such as a triangle or a square can be mentioned. The area of each thermocompression bonding portion is preferably ^{about 0.2 to 2} mm 2, and the density of the non-thermocompression bonding portion is preferably about ^{15 to 70 pieces / cm 2.} The shape of the convex portion of the embossed roll is the shape of the thermocompression bonding portion formed on the non-woven fabric, and the shape of the concave portion of the embossed roll is the shape of the non-thermocompression bonding portion formed on the non-woven fabric. The ratio of the area occupied by the convex portion to the entire surface of the embossed roll (area ratio of the convex portion) is the thermocompression bonding portion and the non-thermocompression bonding portion (region formed by simply depositing fibers) formed on the obtained non-woven fabric. 25 to 50% is preferable in consideration of the balance of. It is considered that when the content is 25% or more, a region of continuous thermocompression bonding portions can be formed to a certain level or more, and tearing can be easily performed. Further, by setting the upper limit to 50%, the obtained non-woven fabric is provided with flexibility and practical mechanical strength by securing a region other than the thermocompression bonding portion (a region where fibers are deposited). be able to.

As the embossing device used for the thermal embossing, it is preferable to use a device including an embossing roll and a flat roll having the above-mentioned uneven engraving pattern.

An arbitrary agent such as an antistatic agent may be attached to the heat-embossed nonwoven fabric by coating or the like as long as the object of the present invention is not impaired.

<Polyolefin resin layer>
A polyolefin resin layer is laminated on one side of the spunbonded non-woven fabric. Since the sheath component of the fiber constituting the spunbonded non-woven fabric is a polyolefin-based polymer, the resin layer to be laminated is a polyolefin having high compatibility with this.

As the polyolefin resin layer, basically, the same type of polyolefin as the sheath component of the core-sheath type composite long fiber is used, so it will not be described again here. The polyolefin used is preferably the same type because of the compatibility with the sheath component of the core-sheath type composite long fiber, but different polyolefins may be used.

<Laminating method>
The spunbonded non-woven fabric and the polyolefin resin layer are prepared separately (for example, a polyolefin film is prepared as the polyolefin resin layer), and one side of the spunbonded non-woven fabric is melted only at the sheath portion, that is, the melting point of the core portion. It can be laminated by heating it to a temperature lower than the melting point of the sheath and pressing the two together, but the polyolefin resin is extruded in a molten state onto a spunbonded non-woven fabric transported from a molten die to cool it. The method of crimping between the rolls to join and integrate is preferable because the polyolefin resin penetrates more into the spunbonded non-woven fabric and integrates. Since the polyolefin resin layer is laminated in a molten state, the polyolefin in the sheath of the spunbonded non-woven fabric is also easily softened, and the polyolefin resin layer and the spunbonded non-woven fabric are more firmly adhered and integrated, and the tearability is easy. It will be good. The polyolefin resin layer is preferably bonded and integrated so that the side in contact with the flat roll is the side facing the polyolefin resin layer in the thermal embossing process when the spunbonded nonwoven fabric forms the thermocompression bonding portion. In particular, when the polyolefin resin layer is formed by the melt extrusion described above, the polyolefin resin easily enters the spunbonded non-woven fabric, and can be better integrated and a uniform layer can be formed.

<Packaging material>
As described above, the packaging material of the present invention is obtained by laminating a polyolefin resin layer on a spunbonded non-woven fabric made of a core-sheath type composite long fiber having a core made of a polyester polymer and a sheath made of a polyolefin polymer. The spunbonded non-woven fabric has a heat-bonded portion having a specific shape (that is, a shape in which the heat-bonded portion surrounds the non-heat-bonded portion).

The packaging material of the present invention will be described with reference to FIG. The packaging material of the present invention is used for packaging various articles (not shown), that is, articles to be packaged (hereinafter, referred to as "packaging articles"). The packaging material 1 of the present invention is composed of a non-woven fabric layer 2 and a polyolefin resin layer 3 laminated on one side thereof. The packaging material 1 is superposed so that the polyolefin resin layers 3 face each other, heat-sealed at necessary points, and the heat-sealed portion 4 is adhered to form a bag-shaped or tubular shape, and the packaged article is formed through the opening 5. The article can be packaged by inserting the plastic into the interior and then heat-sealing the opening 5. In FIG. 3, the packaging material 1 of the present invention is bent and overlapped so that the polyolefin resin layers 3 face each other, and the heat-sealing portion 4 is formed at the end of the folded packaging material 1 by heat sealing. A bag having an opening 5 is formed, and a packaged article is inserted through the opening 5, and then a heat-sealed planned portion 6 near the opening 5 is heat-sealed to wrap the packaged article. When the polyolefin resin layer sides are opposed to each other and heat is applied from the opposite side (non-woven fabric side) to heat-seal, all the polyolefins constituting the polyolefin resin layer are fused and have a strong sealing property, at least at the heat-sealing location. This is because it exerts. Further, since the spunbonded non-woven fabric side has high strength, it is possible to play a good role of protecting the packaged article inside by setting the spunbonded non-woven fabric side to the outside. At the heat-sealed portion, the sheath portion constituting the spunbonded non-woven fabric is also melted or softened, which contributes to adhesion.

Heat sealing is usually performed in the mechanical direction (MD direction) of the packaging material and the transverse direction (CD direction) perpendicular to the mechanical direction. In FIG. 3, the MD direction 7 and the CD direction 8 are indicated by arrows, and the MD direction 7 is the direction in which the fibers are mainly oriented, so that tearing, that is, opening is easy. In FIG. 3, when the packaged article is inserted through the opening 5 and the surroundings are heat-sealed, the package becomes a package, but the end portion of the planned heat-sealed portion 6 that is not the heat-sealed portion is in the MD direction. By providing the notch 9 notched in, the notch 9 can be easily torn by a finger to open the package. The packaging material of the present invention has an advantage that it can be easily torn by starting from a notch formed on the article side of the end of the heat seal. The size of the notch 9 is not particularly limited, but it is preferable to form a notch with a depth of 5 mm to 20 mm, which is easily torn by a human finger. The shape of the notch 9 cut in the MD direction may be a simple notch or a notch shape as shown in FIG. Although the notch is formed at only one place in FIG. 3, there is no problem even if it is formed at a plurality of places.

<Packaging body>
In the present invention, a package is heat-sealed to form a notch. Therefore, in the package, the packaged article is present inside, and the opening is heat-sealed by heat-sealing, and the end of the place where the heat-sealing is expected to be torn is cut in the MD direction. It has a notch. The package can be easily torn starting from the notch. However, the package has a performance capable of sufficiently protecting the article packaged inside. That is, the package has toughness that does not easily tear, and the non-woven fabric has elasticity, so that the article can be protected from a weak impact or the like. Further, since the package is a non-woven fabric, it is not possible to clearly confirm the article, but since it is slightly transparent, the article inside can be confirmed, so that there is no mistake in the article during delivery or transportation.

[Example]
The present invention will be described in more detail by way of examples. The present invention is not limited to these examples.

Example 1
<Spanbond non-woven fabric>
Polyethylene terephthalate (melting point 258 ° C., intrinsic viscosity 0.70) was prepared as a polyester-based polymer to be arranged on the core. High-density polyethylene (melting point 128 ° C., melt index value 25 g / 10 minutes) was prepared as the polyethylene to be arranged on the sheath. After individually weighing so that the sheath / core = 35/65 (mass ratio), the mixture was melted using an individual extruder type extruder and melt-spun so as to have a core-sheath type composite cross section. After the spun yarn was cooled, it was taken up at high speed by air soccer, opened by a known fiber spreader, and collected and deposited on a moving collecting surface to form a non-woven web composed of continuous fibers. The single fiber fineness of the obtained core-sheath type composite continuous fiber was 3 dtex. Further, this non-woven web was passed through a thermal embossing device composed of an embossing roll and a flat roll to form a thermocompression bonding portion. The embossed roll engraving pattern is an engraving pattern in which the convex parts continuously surround the concave parts, the individual concave parts are elliptical, and the long axes of the ellipses are arranged alternately (as shown in FIG. 1). The pattern) is a repeating pattern, in which the area of each recess is 1.14 mm ² , the density of the recess is 64 / cm ² , and the ratio of the area occupied by the convex to the entire surface of the emboss roll (convex). Using an embossing roll having an area ratio of 37%, heat embossing was performed at a heat embossing temperature of 123 ° C. and a linear pressure of 200 N to obtain a spunbonded non-woven fabric having a heat-bonded portion having a ^{grain size of 30 g / m 2.} Since it is a spunbonded non-woven fabric, the long fibers constituting the non-woven fabric are mainly arranged in the MD direction due to the manufacturing method thereof.

<Lamination>
Using an extrusion laminating device, low-density polyethylene for laminating is put into an extruder, heated to 210 ° C. to melt it, and the molten polyethylene sheet is extruded from the die to a thickness of 10 μm and directly under the die. At a location of about 50 cm, the spunbonded non-woven fabric obtained above is laminated, and at the same time, it is introduced between a pair of cooling rolls, and the laminated sheets are pressure-welded between the cooling rolls to join and integrate them to form the packaging material of the present invention. Obtained. The polyethylene sheet was joined and integrated so that the side in contact with the flat roll was the side facing the polyethylene sheet in the thermal embossing process when the spunbonded nonwoven fabric formed the thermocompression bonding portion. In the spunbonded non-woven fabric of the packaging material, the side in contact with the embossed roll is exposed on the surface, so that the abrasion resistance is improved.

<Packaging material>
The spunbonded non-woven fabric before laminating has a thickness of 0.16 mm, a tensile strength (MD direction) of 145N / 5cm, a tensile strength (CD direction) of 55N / 5cm, and a tear strength (MD direction) of 3.0N. The packaging material in which the polyethylene resin layer (polyethylene sheet) is joined and integrated is 0.13 mm thick, tensile strength (MD direction) 167N / 5cm, tensile strength (CD direction) 55N / 5cm, tear strength (MD direction). The fluffiness was 2.1N, and at 5 test pieces, most of the test pieces had no change in the surface state before the start of the test, and almost no fluff was observed. Tensile strength, tensile strength and fluffiness were measured by the methods described below.

Further, it was possible to easily grasp the printed contents in a state where the wrapping material was superposed on the A4 paper on which characters and patterns were printed (the A4 sheet side was the polyethylene resin layer side) and the wrapping material was overlapped. Therefore, when the package is used, the characters and the like written on the stored items can be grasped through the package.

<Tensile strength (N / 5 cm width)>
Prepare 10 test pieces with a width of 5 cm and a length of 20 cm, and use a constant-speed extension type tensile tester (manufactured by Orientec, trade name "UTM-4-1-100") to apply to JIS-L-1913. It was measured according to the above. The conditions at this time were a gripping interval of 100 mm and a tensile speed of 200 mm / min. An elongation-load curve was drawn, and the required maximum load strength (N / 5 cm width) was measured from the obtained elongation-load curve, and the average value of 10 points was taken as the tensile strength.

<Tear strength (N)>
JIS L 1913 Tear strength Measured based on the Pendulum method. The measurement was performed only in the MD direction.

<Fluffing>
The fluffing property was evaluated according to the JIS L 0849 wear tester type II (Gakushin type) method. Instead of the white cotton cloth for friction, the same material as the test piece was used for friction, and the test pieces were abraded with each other. The number of reciprocating frictions was 50, and the surface condition of the test piece (N = 5) at that time was observed.

<Packaging body>
Two pieces of the obtained packaging material cut into a size of 180 cm (MD direction) x 90 cm (CD direction) are stacked so that the polyethylene resin layers face each other, and the edges of the packaging material are used using a heat sealer. A heat-sealed portion having a width of about 5 mm was formed on three overlapping sides at a location about 1 cm from the portion to form a bag shape. Approximately 5 kg of cargo was stored through the unheat-sealed opening, and the opening was similarly heat-sealed and closed to form a package with four sides heat-sealed.

In the package in which the transported material is stored, a notch (about 8 mm) cut in the MD direction is made at one place near the heat-sealed portion at the end of the package to form a notch.

When the package containing about 5 kg of the transported material was vibrated or released, the heat-sealed portion was maintained without being destroyed and played a role of protecting the transported material as the contents. Further, when the notch portion of the notch was pinched and split in the MD direction, the notch portion could be easily split and the contents (carried matter) could be taken out.

Comparative Example 1
Spun-bonded non-woven fabric composed only of polyethylene terephthalate (Product name "Marix 70303WSO" manufactured by Unitika Ltd.) Single fiber fineness 3dtex, grain 30g / m ² , partial thermocompression bonding part is formed in a scattered spot shape Is approximately square and has a crimping area ratio of 16%).

A polyethylene sheet was laminated on the spunbonded non-woven fabric in the same manner as in Example 1 to obtain a laminated sheet formed by laminating and integrating.

The laminated sheet in which a polyethylene resin layer (polyethylene sheet) is joined and integrated with a spunbonded non-woven fabric has a thickness of 0.15 mm, a tensile strength (MD direction) of 99 N / 5 cm, a tensile strength (CD direction) of 48 N / 5 cm, and a tear strength (MD direction). Direction) 3.6N, and the fluffing property was fluffing at 5 points of the test piece, and most of the test pieces had fluff generated due to friction on the surface, and some of the generated fluff was entangled to generate fluff. Further, when the notch portion of the notch was pinched and split in the MD direction, it could not be easily split.

As is clear from the comparison between Example 1 and Comparative Example 1, the tensile strength and fluffing property of Comparative Example 1 are inferior to those of the laminated sheet of Example. Further, the tear strength is smaller in the value of the example, and it can be seen that the example easily tears and takes out the contents when taking out the contents. In Comparative Example 1, since the non-woven fabric is formed of long fibers that do not have a core-sheath structure, even if the polyethylene resin layers are laminated, the easiness of tearing starting from the notch is not obtained.

1 ... Packaging material 2 ... Spun-bonded non-woven fabric 3 ... Polyolefin resin layer 4 ... Heat seal part 5 ... Opening 6 ... Heat seal planned part 7 ... Machine direction (MD direction)
8 ... Crossing direction (CD direction)
9 ... Notch

Claims (8)

A polyolefin resin layer on one side of a spunbonded non-woven fabric made of a core-sheath type composite long fiber composed of a thermoplastic polymer having a sheath portion of a polyolefin-based polymer and a core portion having a melting point higher than the melting point of the polyolefin-based polymer of the sheath portion. The spunbonded non-woven fabric has a heat-bonded portion, and the heat-bonded portion maintains the fiber morphology by melting or resolidifying the polyolefin-based polymer in the sheath portion of the core-sheath type composite long fiber after melting or softening. A packaging material in which the cores are bonded to each other, and a continuous concave heat-bonded portion surrounds the non-heat-bonded portion. The packaging material according to claim 1, wherein the thermoplastic polymer in the core portion is a polyester-based polymer, and the melting point of the core portion is higher than the melting point of the polyolefin-based polymer constituting the sheath portion by 30 ° C. or more. The packaging material according to claim 1 or 2, wherein the melting point of the polyolefin resin layer is substantially the same as the melting point of the polyolefin constituting the sheath component. The packaging material according to any one of claims 1 to 3, wherein the spunbonded non-woven fabric has a basis weight of 20 to 40 g / m ^2. The packaging material according to any one of claims 1 to 4, wherein the core-sheath type composite long fiber has a single fiber fineness of 1 to 10 decitex. A packaging body obtained by stacking the packaging materials according to claim 1 so that the polyolefin resin layer sides face each other and heat-sealing at least the mechanical direction of the spunbonded non-woven fabric, and cutting in the mechanical direction in the vicinity of the heat-sealed portion. A packaging body with a sewn notch. The package according to claim 6, wherein the spunbonded non-woven fabric is heat-sealed not only in the mechanical direction but also in the transverse direction. The package according to claim 6 or 7, which includes an article to be packaged.

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