JP3193246B2 - Paper bag - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper bag, and more particularly, to a paper bag suitable for storing heavy objects such as sugar, salt and feed.

[0002]

2. Description of the Related Art Conventionally, so-called paper bags made of paper have been used for storing sugar, salt, and the like. These paper bags are relatively inexpensive, have a moderate air permeability, and Due to its ease of disposal, its use is wide in recent years. Problems with such paper bags are that they are weaker than plastic bags and have poor moisture proofing properties.
No. 43157 and Japanese Utility Model Publication No. 5-44291,
Paper bags with improved strength as a multi-layered structure
No. 44292 discloses a moisture-proof paper bag having an inner layer made of a synthetic resin film.

[0003] Furthermore, Japanese Patent Application Laid-Open No. 64-20451 and US Patent No. 2,923,457 disclose that the opening operation is made easier by straddling the opening portion of the bag body. A paper bag which is covered with paper and to which a cut tape for opening is attached along a fold line of the backing paper is disclosed. When opening the paper bag, the cut tape causes the tab to be attached to the end, so that the backing paper closing the opening is torn along the fold line. It can be easily opened without using it.

On the other hand, in order to improve the capacity of storing bags,
A so-called gusset is formed by folding the side of a bag inward. Since this gusset is folded inside when not in use, the size of the appearance does not change from the bag that does not form a gusset, the folded part expands when storing things in the bag, increasing the volume in the thickness direction,
This allows for a large capacity.

[0005]

However, when such a gusset structure is applied to a paper bag having a backing sheet adhered so as to close the opening, the end of the gusset, that is, the opening side is weak in strength. In the state where the contents are accommodated, a gap may be formed at the end of the gusset, or in an extreme case, the gusset may be torn from the end. In particular, in the case of a paper bag, unlike the case made of resin such as polyethylene, bonding by welding cannot be performed, so that it is difficult to treat the gusset end.

As a countermeasure, for example, it is conceivable to cover the end of the gusset with a piece of paper or the like and fix it so as not to open it. However, there is a problem that the contents easily remain at the end of the gusset. Such a residue does not cause a particular problem in the case of sugar or the like, but tends to cause spoilage in the case of feed or the like.

The problem to be solved by the present invention is to increase the strength of the end portion of the gusset with a relatively simple structure, to improve the safety at the time of storage, and to reduce the residual of the contents at the time of removal. .

[0008]

SUMMARY OF THE INVENTION The present invention has been proposed to solve the above-mentioned problems, and has a feature in the structure of the opening. That is, according to the present invention, a backing sheet having an opening cut tape is adhered to the opening of the tubular paper bag main body, and both ends of the opening of the paper bag main body are formed in the paper bag formed with the gusset on the side surface of the paper bag main body. The step cut portion formed in the portion is bent toward the paper bag main body surface side so as to close the opening, and the same step cut portion is surrounded by the backing sheet, and further, the cut tape is placed above and below the step cut portion. Are provided with the first and second tapes respectively provided in the paper bag. Here, it is preferable to apply a release agent to the surface of the paper bag main body for the purpose of easily peeling off the backing paper between the first and second cut tapes.

[0009]

According to the present invention, the stepped portions formed on both side edges of the opening of the paper bag body are bent toward the front side of the paper bag body so as to close the opening, and the stepped portions are surrounded by the backing paper. The thickness of the gusset portion is added to the thickness, that is, the end portion of the gusset is closed at a stepped portion having a thickness four times the thickness of the paper bag main body. Is reliably prevented from opening. In addition, since the stepped portion is simply bent and fixed from the upper surface by the backing paper, by pulling up the first and second tapes respectively disposed at the upper and lower portions of the stepped portion, The backing paper between the first and second tapes is peeled off, and the stepped portion under the tape is unconstrained.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The construction of the present invention will be specifically described below based on embodiments shown in the drawings. FIG. 1 is a perspective view showing a paper bag according to an embodiment of the present invention partially cut away, FIG. 2 is a front view of the paper bag shown in FIG. 1, FIG. 3 is a cross-sectional view taken along line AA of FIG. 1, and FIG. 1 is a sectional view taken along line BB of FIG. Referring to FIG. 1, reference numeral 1 denotes a tubular paper bag main body whose end face is bonded with an adhesive,
a and the outer layer 1b. One end (upper end in the drawing) of the paper bag main body 1 is open, and a backing paper 2 that covers the opening of the paper bag main body 1 and closes the opening is adhered to the other end (lower end in the drawing). Reference numeral 3 denotes a gusset formed by folding both sides of the paper bag body 1 inward to increase the storage amount.

FIG. 5 is a partial perspective view of the backing sheet. As shown in FIG. 5, an adhesive layer 6 is provided on the entire inner surface of the backing sheet 2, and the backing sheet 2 extends along the center fold line. And a second cut tape 4b is adhered in the middle of one surface of the backing sheet 2 in parallel with the first cut tape 4a. In the present embodiment, the first and second cut tapes 4
The cut tape 4 for opening is constituted by a and 4b.

Also, as clearly shown in FIGS. 1 and 2,
The backing paper 2 has both ends protruding from the paper bag main body 1, and a cut 2 a is formed at the boundary of the paper bag main body 1.
This protruding portion is used as a knob 2b for opening the paper bag. The gusset 3 is formed by folding both sides of the paper bag main body 1 inward to form a fold in order to increase the storage capacity of the paper bag main body 1. The gusset 3 has a force in the direction in which the fold is stretched by the stored items. In particular, it acts intensively on the end of the gusset 3, and the end is easily broken.

In order to prevent such damage, as shown in FIG. 6, a stepped portion 5 projecting from the end of the paper bag body 1 is provided.
Are formed at both ends of the opening of the paper bag main body 1, and as clearly shown in FIG. 7, the stepped portion 5 is bent toward the surface side of the paper bag main body 1, and is surrounded by the backing paper 2 from above. It is bonded to form a reinforcing part. With such a structure, the end portion of the gusset is closed by the stepped portion 5 having a thickness four times the thickness of the paper bag main body 1, so that the end portion of the gusset 3 is not broken in the stored state, thereby improving safety. Can be done.

Further, as shown in FIG. 7, since the inner edge 5a of the stepped portion 5 is projected to the inside of the fold 3a of the gusset 3, the end of the gusset 3 is completely surrounded and reinforced.
In addition, the end of the gusset 3 is closed without a gap, thereby improving safety. In the above-described paper bag, in the conventional manufacturing process, the stepped portion 5 is formed at the time of cutting, and this is folded into the front surface side of the bag body 1 to reinforce the end of the gusset 3, and the manufacturing process is greatly reduced. No changes are needed.

Referring to FIG. 1, when opening the paper bag, the tab 2b of the backing sheet 2 is lifted so that the tab 2b is torn from the cut 2a and pulled in the opposite direction. Of the two, the portion sandwiched between the first cut tape 4a and the second cut tape 4b is torn together. At this time, when a release agent is applied to the surface of the outer layer 1b, the backing paper 2 between the first cut tape 4a and the second cut tape 4b can be more smoothly peeled off.

This completes the opening operation. However, since the stepped portion 5 is simply bent and fixed from the upper surface thereof with the backing sheet 2, the stepped portion 5 is disposed above and below the stepped portion 5, respectively. First and second tapes 4
By pulling up a and 4b, the stepped section 5 below the backing sheet 2 is in an unconstrained state.

Therefore, when the contents are taken out by turning the paper bag 1 upside down in this state, as shown in FIG.
Is restored to the state before bending, and the contents can be completely taken out without leaving the contents in the paper bag main body 1 or the stepped section 5. As described above, in the paper bag of the present embodiment, the strength of the end portion of the gusset can be increased with a relatively simple structure, and the safety at the time of storage can be improved, and the residual content at the time of removal can be reduced. Can be.

In the paper bag of this embodiment, the upper end is left open, but the opening is filled with contents by a user and then sealed with hot melt or the like. Further, the above structure is not limited to a paper bag having an open upper end as in the present embodiment, but it is a matter of course that the above structure can be applied to a material sealed by bonding or sewing.

[0019]

According to the present invention, the following effects can be obtained. (A) The gusset end is closed at a stepped portion having a thickness four times the thickness of the paper bag main body, whereby the opening of the gusset end when an object is stored in the bag is reliably prevented, Storage safety is improved. (B) Since the stepped portion is simply bent and fixed from the upper surface by the backing sheet, the backing sheet is peeled off by pulling up the first and second tapes, and the stepped portion below the backing sheet is not restrained. In this state, the contents can be completely removed without leaving the contents in the step section.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a paper bag according to an embodiment of the present invention with a part cut away.

FIG. 2 is a front view of the paper bag shown in FIG.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is a sectional view taken along line BB of FIG. 1;

FIG. 5 is a partial perspective view of a backing sheet adhered to the paper bag shown in FIG. 1;

FIG. 6 is a front view showing a process of manufacturing the paper bag main body shown in FIG.

7 is a partially cutaway perspective view showing a main part of the paper bag shown in FIG.

FIG. 8 is an explanatory diagram showing a state of taking out stored items from a paper bag.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Paper bag main body 1a Inner layer 1b Outer layer 2 Backing paper 2a Cut 2b Grip 3 Gusset 3a Gusset crease 4 Cut tape 4a First cut tape 4b Second cut tape 5 Step cut 5a Inner edge of step cut 6 Adhesive layer

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B65D 30/20 B65D 33/00 B65D 33/02 B65D 33/36-33/38

Claims (1)

(57) [Claims] 1. A paper bag having a gusset formed on a side surface of the paper bag main body, and a backing sheet having a cut tape for opening is adhered to an opening of the cylindrical paper bag main body. The formed stepped portion is bent toward the surface of the paper bag body so as to close the opening, and the stepped portion is surrounded by the backing sheet.Furthermore, the cut tape is provided at the upper part and the lower part of the stepped part, respectively. A paper bag comprising the first and second cut tapes provided.