JP3375212B2 - Storage bag for documents, etc. - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a storage bag for documents and the like, which is made of synthetic resin and has a thin material and is excellent in strength.

[0002]

2. Description of the Related Art Conventionally, a film such as polyethylene or polyvinyl chloride has been used as a material for a synthetic resin storage bag. However, since these films have relatively low strength, they are easily damaged when accommodating heavy documents or handling them roughly. Therefore, when strength is required, it is necessary to increase the thickness of the material, which is disadvantageous in terms of manufacturing cost.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to improve the above points and to provide a thin and strong bag for storing documents and the like.

[0004]

Means for Solving the Problems The inventors of the present invention have made earnest studies in accordance with the above-mentioned object, and as a result, by using a sheet-like laminated material obtained by laminating a reticulate body and a base film, it is thin and strong. The present invention has been completed by finding that a storage bag having a large size can be obtained. That is, the present invention has a rectangular accommodating portion having a front wall and a back wall, and a lid piece connected to the back wall, wherein the front wall, the back wall and the lid piece include at least a net-like body and a base film. The present invention relates to a storage bag, which is formed of a sheet-shaped laminated material obtained by stacking

FIG. 1 shows an embodiment of the storage bag of the present invention.
FIG. 1A is a schematic front view of the storage bag, and FIG. 1B is a horizontal sectional view taken along the line bb of FIG. The storage bag 1 shown in FIG. 1A has a front wall 2, a back wall 3, and a lid piece 4 connected to the back wall 3. As shown in FIG. 2B, the sheet-shaped laminated material 5 forming the front wall 2, the back wall 3 and the lid piece 4 is composed of a mesh body 6 and a base film 7.
Are laminated via an adhesive layer 8 as required. It is also possible to add layers made of other materials. The storage bag 1 of the present invention is formed by integrally folding the front wall 2, the back wall 3 and the lid piece 4 by folding back the rectangular sheet-shaped laminated material 5 along a line perpendicular to its long side. Then
Further, it can be formed by overlapping and joining both side edges of the front wall 2 and the back wall 3. As a method of joining the edges, in addition to heat bonding, ultrasonic welding, or the like, they may be joined by sewing. Further, in order to improve the strength and enhance the commercial value, as shown in FIGS. (A) and (b), the both side edge portions, the front wall and the edge of the lid piece are covered with the edging tape 9 from the outside. Can also be sewn
It

The mesh body 6 used in the present invention is composed of a multilayered body of thermoplastic resin described later. In particular, it is preferable that the crystalline low melting point resin layer is provided on one side or both sides of the crystalline high melting point resin layer. Specifically, it is selected from the constitutions described below. (1) A low melting point resin layer is provided on one or both sides of the high melting point resin layer.
Laminated uniaxially oriented reticulated film (2) Graft-weft laminated reticulated film obtained by laminating the uniaxially oriented reticulated films so that their orientation directions intersect each other (3) A laminate comprising the high melting point resin layer and the low melting point resin layer the uniaxially oriented, uniaxially oriented tape made by cutting before or after orientation, laminated crosswise nonwoven (4) so that the orientation direction intersecting woven background to orient the uniaxially oriented tape directions cross Woven fabric (5) A laminate obtained by laminating the uniaxially oriented network film and the uniaxially oriented tape so that the orientation directions intersect with each other.

FIG. 2 shows an example of the uniaxially oriented network film (1). FIG. 2A is a partially enlarged perspective view showing an example of a vertically uniaxially oriented reticulated film. The longitudinal uniaxially oriented reticulated film 10 is obtained by laminating the high melting point resin layer 11 and the low melting point resin layer 12 and performing uniaxial orientation in the longitudinal direction (the transport direction of the film), and then splitting and widening the fibers in the longitudinal direction with a splitter. It is a thing. FIG. 2B is a partially enlarged perspective view showing an example of a lateral uniaxially oriented reticulated film. The lateral uniaxially oriented reticulated film 10a is obtained by laminating the high melting point resin layer 11 and the low melting point resin layer 12, finely oriented in the longitudinal direction as needed, and then slitting the film in the transverse direction (the width direction of the film) with a hot blade or the like. Giving,
It is uniaxially oriented in the lateral direction.

[0008] Fig. 3 shows an example of the above-mentioned (2) history-weft laminated network film. FIG. 3A is a partial front view of a warp-weft laminated reticulated film made of a longitudinal uniaxially oriented reticulated film, and FIG. 3B is an enlarged end view taken along the line bb of FIG. And show it. The warp-weft laminated reticulated film 13 is obtained by laminating the longitudinally uniaxially oriented reticulated film 10 shown in FIG. 2A so that the orientation axes cross each other and heat-fixing.

FIG. 4 is a partial perspective view of the uniaxially oriented tape described in (3) above. The uniaxially oriented tape 14 is obtained by laminating the high melting point resin layer 11 and the low melting point resin layer 12, orienting it in the uniaxial direction, and cutting it before or after orientation. The width of the stretched tape is generally 3 mm to 50 m.
m, preferably 5 mm to 30 mm.

FIG. 5 is a partial front view of a non-woven fabric in which the uniaxially oriented tape 14 (3) is laminated in a weft direction. Further, FIG. 6 is a partial front view of a woven fabric woven by laminating the uniaxially oriented tape (4) described above in a weft and weft manner. The non-woven fabric 15 and the woven fabric 16 are
Both are formed by using the uniaxially oriented tape 14 shown in FIG.

In the above-mentioned orientation treatment, the orientation magnification (elongation magnification) is in the range of 1.1 to 15 times, but it is desirable to orient in a plurality of stages in order to prevent uneven stretching.
For example, in the first stage, the primary orientation is 1.1 to 8 times, preferably 5 to 7 times, and further, in the second stage and thereafter, the extension ratio is 5 to 15 times, preferably 6 to 10 times with respect to the initial dimension. Secondary and tertiary orientations are performed. If the orientation magnification of the multilayer uniaxially oriented body is less than 1.1 times, the mechanical strength of the woven or non-woven fabric is insufficient. On the other hand, when the orientation magnification exceeds 15 times, it is difficult to perform the orientation by the usual method, and there arises a problem that an expensive device is required. The most preferable method for heat setting is a method in which the woven fabric or the laminated sheet is continuously heated and fixed while rotating on a heating cylinder drum.

The orientation method may be either a rolling method or a stretching method. In the stretching method, the quasi-uniaxial stretching method is particularly preferable. The rolling method in the present invention means that a thermoplastic resin film is passed between two heating rolls having a gap smaller than its thickness, and is pressed at a temperature lower than the melting point (softening point) of the resin film to obtain a thickness. A method of extending the length by the amount of decrease. The quasi-uniaxial stretching method is a method in which a thermoplastic resin film is passed between a low-speed roll and a high-speed roll (proximity roll) with a roll gap as small as possible, and stretching is performed while suppressing shrinkage in the width direction as small as possible.

The thickness ratio of the high melting point resin layer and the low melting point resin layer used for the mesh is not particularly limited, but when the low melting point resin is used as the adhesive layer, the thickness thereof is 50% or less of the total thickness, It is preferably 40% or less. If the thickness of the low melting point resin layer is 3 μm or more, various physical properties such as adhesive strength at the time of heat bonding can be satisfied, but preferably 5 to 100 μm
Selected from the range of.

The high melting point resin used in the present invention is
Medium density polyethylene, polypropylene, polybutene
1, poly-4-methylpentene-1, polyhexene-1
Examples thereof include homopolymers of α-olefins such as, and polyolefins such as copolymers of α-olefins such as propylene-ethylene copolymer, and thermoplastic resins such as polyamide, polyester, polycarbonate and polyvinyl alcohol.

As the low melting point resin used in the present invention,
Medium / low density polyethylene, linear low density polyethylene,
Ultra-low density polyethylene, ethylene-vinyl acetate copolymer; ethylene-acrylic acid copolymer and ethylene-methacrylic acid copolymer; ethylene-acrylic acid ester copolymer such as ethylene-ethyl acrylate copolymer and ethylene- Methacrylic acid ester copolymer; ethylene-
(Maleic acid or its ester) copolymer; propylene-based polymer such as polypropylene and propylene-ethylene copolymer; polyolefin modified with unsaturated carboxylic acid;
A thermoplastic resin such as a copolyester is exemplified. For manufacturing reasons, the difference in melting point from the high melting point resin needs to be 5 ° C. or higher, and preferably 10 to 50 ° C. or higher.

As a concrete laminated constitution of the resin in the reticulated body, high density polyethylene (HDPE) / low density polyethylene (LDPE), LDPE / HDPE / LDP
E, HDPE / ethylene-vinyl acetate copolymer (EV
A), EVA / HDPE / EVA, HDPE / Linear low density polyethylene (LLDPE), LLDPE / HDPE
/ LLDPE, polypropylene (PP) / propylene-
Ethylene copolymer (PEC), PEC / PP / PEC,
Polyester (PEs) / Copolyester (CPE
s), CPEs / PEs / CPEs and the like.

In the present invention, examples of the material for the base film which is used by laminating it with the reticulate body include polyolefin resins such as polyethylene and polypropylene, polyester resins, polyamide resins, polycarbonate, cellophane and the like. It is a film in which a resin is oriented by stretching or rolling. Specifically, oriented polypropylene (OPP), oriented polyester (OPE)
T), oriented polyamide (ONY) and the like, and oriented polypropylene (OPP) is most preferable from the viewpoints of transparency, mechanical strength and economical efficiency.

In the present invention, in order to laminate the reticulate body and the above-mentioned base film into a sheet-like laminated material, they are directly heat-sealed or bonded via an adhesive layer. As the adhesive layer, medium / low density polyethylene, linear low density polyethylene, ultra low density polyethylene, ethylene-vinyl acetate copolymer; ethylene-acrylic acid copolymer and ethylene-methacrylic acid copolymer; ethylene-acrylic Ethylene-acrylic acid ester copolymers and ethylene-methacrylic acid ester copolymers such as ethyl acid acid copolymers; ethylene- (maleic acid or its ester) copolymers; propylene-based polymers such as polypropylene and propylene-ethylene copolymers Polymers; polyolefins modified with unsaturated carboxylic acids; copolymerized polyesters, etc., but polyethylene resins, heat-sealing strength, economical efficiency, etc.
In particular, polyethylene whose main component is linear low-density polyethylene is preferable. The adhesive layer is laminated on the film in advance by a method such as extrusion lamination or dry lamination.

As a material for the edging tape for covering the edge portion of the sheet-like laminated material, a film of ethylene-vinyl acetate copolymer (EVA) as well as a nylon or polyester woven fabric can be used. By coloring the edging tape in advance, the effect of increasing the commercial value can be obtained. In order to enhance the decorativeness, the high melting point resin layer and / or the low melting point resin of the net-like body forming the storage bag can be colored with an appropriate colorant such as a pigment or dye.

The present invention will be described below with reference to examples. <Example 1> High density polyethylene (MFR 1.0g / 10mi) was used as a high melting point thermoplastic resin layer by the multilayer water cooling inflation method.
n, density 0.956 g / cm ³ , melting point 129 ° C .; trade name: Nisseki Staflen E710, manufactured by Nippon Petrochemical Co., Ltd., hereinafter “H
"DPE") is used for the inner layer, and low density polyethylene (MFR3.
0 g / 10 min, density 0.924 g / cm ³ , melting point 109 ° C .; trade name: Nisseki Lexlon F30, manufactured by Nippon Petrochemical Co., Ltd., hereinafter referred to as “LDPE”), and a thickness of 15 μm (LD
PE) / 100 μm (HDPE) / 15 μm (LDP
The laminated film of E) was produced, and the obtained laminated film was stretched 8 times and then split to obtain a vertically uniaxially oriented reticulated film having a three-layer structure having a basis weight of 18 g / m ² and a width of 1 m. (Fig. 2
reference). Next, a longitudinal uniaxially oriented reticulated film was laminated so that the orientation axes were orthogonal to each other to produce a warp-weft laminated reticulated film (see FIG. 3). A linear low density polyethylene (hereinafter referred to as "LLDPE") was laminated as an adhesive layer on a base film of oriented polypropylene (OPP) by a dry lamination method to obtain a laminate. A sheet-like laminated material was produced by polymerizing the above-mentioned history laminated network film and the surface of the laminate on the LLDPE side and thermally adhering them. The obtained sheet-shaped laminated material is cut into a rectangular shape, folded back with the OPP film on the outside, both side edges of the front wall and the back wall are polymerized, and the entire edge of the sheet-shaped laminated material is covered with edging tape and sewn. A storage bag as shown in FIG. 1 was obtained. The obtained storage bag was thin, flexible, and superior in strength to conventional products .

[0021]

As described above, the storage bag of the present invention is thin and flexible and excellent in strength because it uses the sheet-like laminated material in which the net body and the film are laminated.

[Brief description of drawings]

FIG. 1 (a) is a schematic front view of an embodiment of the present invention,
(B) is sectional drawing in the bb line of (a).

FIG. 2 shows an example of a uniaxially oriented reticulated film. (A) is a partially enlarged perspective view of a longitudinal uniaxially oriented reticulated film, and (b) is
FIG. 3 is a partially enlarged perspective view of a lateral uniaxially oriented reticulated film.

FIG. 3 shows an example of a warp-weft laminated network film. (A) is a partial front view of a longitudinal-weft laminated reticulated film made of a longitudinal uniaxially oriented reticulated film, and (b) is an enlarged end view taken along line bb of (a).

FIG. 4 is a partial perspective view of a uniaxially oriented tape.

FIG. 5 is a partial front view of a nonwoven fabric obtained by laminating uniaxially oriented tapes on the back and weft.

FIG. 6 is a partial perspective view of a woven fabric obtained by weaving a uniaxially oriented tape.

[Explanation of symbols]

1 storage bag 2 front wall 3 back wall 4 lid pieces 5 Sheet-like laminated material 6 reticulated body 7 Base film 8 Adhesive layer 9 edging tape 10 Longitudinal uniaxially oriented reticulated film 10a Horizontal uniaxially oriented reticulated film 11 High melting point resin layer 12 Low melting point resin layer 13 Graft Laminated Reticulated Film 14 Uniaxially oriented tape 15 Nonwoven fabric 16 woven cloth

Claims (2)

(57) [Claims] 1. A rectangular accommodating portion having a front wall and a back wall, and a lid piece connected to the back wall, wherein the front wall, the back wall and the lid piece at least have a base film and a mesh body laminated thereon. in storage bag documents, etc., characterized in that formed by a sheet-like laminated material formed by the mesh-like body is one or both sides of the crystalline high melting point resin layer
A low-melting resin layer having thermal adhesiveness is provided on (1)
Axially oriented reticulated film, (2) the uniaxially oriented reticulated film
Gradient-laminating network composed of latitudinal and latitudinal layers with their orientations intersecting
Film, (3) Uniaxially oriented tape oriented uniaxially
A non-woven fabric formed by laminating the wefts so that the orientation directions intersect.
(4) Pass the uniaxially oriented tape so that the orientation directions intersect.
A woven fabric obtained by weaving, and (5) the uniaxially oriented mesh fabric
The orientation of the film and the uniaxially oriented tape intersect.
Which is one of the laminated bodies formed by laminating the sheet-like laminated material on a line perpendicular to its long side.
By folding back, the front wall, the rear wall and the lid piece
Is formed so as to be integrally connected, and the front surface is
When connecting the wall and back wall, the mesh is inside.
In the existing state, both side edges are overlapped and welded by fusion.
A storage bag for documents etc. 2. A rectangular housing having a front wall and a back wall.
And a lid piece connected to the rear wall, the front surface
At least the base film and the wall, back wall and lid piece
Formed by a sheet-shaped laminated material that is laminated with a mesh
In the storage bag for documents and the like characterized in that the reticulate body is one side or both sides of the crystalline high melting point resin layer.
A low-melting resin layer having thermal adhesiveness is provided on (1)
Axially oriented reticulated film, (2) the uniaxially oriented reticulated film
Gradient-laminating network composed of latitudinal and latitudinal layers with their orientations intersecting
Film, (3) Uniaxially oriented tape oriented uniaxially
A non-woven fabric formed by laminating the wefts so that the orientation directions intersect.
(4) Pass the uniaxially oriented tape so that the orientation directions intersect.
A woven fabric obtained by weaving, and (5) the uniaxial mesh net
The orientation of the film and the uniaxially oriented tape intersect.
Which is one of the laminated bodies formed by laminating the sheet-like laminated material on a line perpendicular to its long side.
By folding back, the front wall, the rear wall and the lid piece
The, along with the formed so as to be connected integrally, before Symbol front
When joining the wall and back wall, both edges and
The edges of the front wall and lid are covered with edging tape from the outside
Storage of documents etc. characterized by being joined together by sewing
bag.