JP2002179093A - Heavy plastic bag for ammonium nitrate-fuel oil explosive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heavy plastic bag for ammonium nitrate-fuel oil explosive which can be easily opened and disposed of. SOLUTION: In forming this heavy plastic bag for ammonium nitrate-fuel oil explosive, a tubular plastic film body part is formed, a sealing part is folded, a folded bump is provided with a cut device, and an over tape is provided on its front and back faces.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heavy plastic bag for an ammonium nitrate explosive, which is used for packing, transporting, and storing the explosive.

[0002]

2. Description of the Related Art As an improvement on a simple opening portion of a heavy bag for an ammonium nitrate explosive, a method of easily opening an overtape with a cutting tool as disclosed in JP-A-6-255658 is disclosed. A method using a water-resistant tape for adhesion of an overtape portion as shown in 183482 report,
Regarding the simplification of the structure of the heavy bag, see JP-A-2000-255.
There is a change from end sewing as shown in the '589 report to heat sealing. Also, heavy bags made of resin films are currently used in the fields of confectionery, cereals, and fertilizers.
As shown in the 887 report, there is a method in which an arc-shaped perforation is previously inserted.

[0003]

The conventional heavy bag for nitrate oil explosives uses 3 to 5 plastic bags, kraft paper, etc. in order to secure oil resistance and water resistance. In addition, since the plastic bags and the kraft paper are adhered by heat sealing, there is a problem that the plastic bag and the kraft paper must be separated due to environmental considerations at the time of disposal, which is complicated for an operator.
In addition, when the seal of the simple opening portion is not satisfactory, there is a possibility that the original performance cannot be maintained or solidified due to moisture absorption which is a feature of nitrite.

[0004] Heavy bags made of resin films are made of grains,
It is used in the field of fertilizers, but heavy bags for nitrate explosives have problems such as light oil and other oil seeping and odors.
In addition, the openability was poor, and the user usually opened the package with a blade such as scissors or a cutter. This requires the use of metal tools that are not desirable at the explosive handling site, which is not desirable in terms of security. In addition, the blasting site is outdoors, and the opening operation in the severe cold season in winter is a precise operation under severe conditions. Also, if a perforation line is inserted for easy opening, in the case of an ammonium nitrate explosive, there is a problem that moisture is absorbed and solidified from the gap, and there is a possibility that oil such as light oil oozes out.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, have paid attention to plastics that do not need to be separated at the time of disposal, and pointed out the problem of heavy bags using existing plastics. The present inventors have found a method for improving the easy opening property and have completed the present invention. That is, the present invention provides a double bag comprising a body having a tubular structure and a sealing portion, wherein the body is made of only a plastic film, and each end is aligned at an opening end, and at least one of the sealing The portion is bent twice or more with the open end inside, and the open end is formed between the bent portion not in contact with the overtape, and the bent portion overlapped by the bending and the non-overlapping trunk portion. A folding step, a cutting tool for cutting the overtape arranged along the folding step, and an overtape coated so as to sandwich the entire front and back surfaces of the sealing portion and entirely bonded to the body surface. It is a plastic heavy bag for ammonium nitrate explosives.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below. A plastic film conforming to the Explosives Control Law is used for the body of the heavy bag used in the present invention. The plastic film of the present invention is selected from single or two or more composite films of thermoplastic plastics such as polyethylene, polypropylene, polyvinyl chloride, polystyrene, nylon, Surlyn, PPO, and biodegradable plastics.

[0007] The thickness of the plastic film of the present invention is 1
It is preferably from 0 μm to 300 μm. 10
If it is less than μm, the handleability is poor, and if it exceeds 300 μm, the cost increases. More preferably 20 μm or more and 200 μm
It is as follows. The oil resistance of the plastic film of the present invention is preferably 30 hours or more according to a measurement method based on JISZ1515. If the plastic film has no oil resistance, the light oil contained in the nitrite explosive will seep out of the heavy bag during transportation and storage, causing odor and deteriorating the performance of the product.

[0008] Antistatic of the plastic film of the present invention
The surface resistivity is 10^Ten-10 ¹¹Ω or less
Preferably. Generally kneading and application of antistatic agent
I do. As an antistatic agent, a cationic surfactant
Certain quaternary ammonium salts, imidazolines, etc. are used.
The tensile strength of the plastic film of the present invention is JISZ1
5 MPa or more and 100 MPa or less according to the measurement method of 702
Preferably it is below. When the tensile strength is less than 5MPa
If it exceeds 100MPa, the cost is high.
Become. More preferably, it is 6 MPa or more and 80 MPa or less.
is there.

The configuration of the present invention will be described with reference to FIG. That is, the heavy bag of the present invention comprises a body (1) having a tubular structure using a plastic film and a sealing portion (one sealing portion is shown here). The end of the body (1) of the heavy bag is 1cm, unlike the one sewn from the top of the overtape.
At least two times with a width of up to 4 cm with the open end of the end inside, along the step formed between the overlapped portion and the non-overlapping portion, that is, along the bent step (5). Cutting tools (6)
And an overtape (2) that holds the overlapping portion by bending so as to sandwich the overlapped portion from the back surface to the front surface, thereby holding down the opening of the heavy bag.

Regarding the method of bonding the overtape (2), the overtape (2) may be bonded by an adhesive, or may be bonded by heat sealing using a processed paper obtained by laminating a resin on the overtape (2). Here, the sealing method on the opening side required to be easy to open the heavy bag has been described, but the sealing portion at the other end may be the same sealing method as described above, or may be a conventional heat sealing method. There is no particular limitation. In order to open the heavy bag, the overtape (2) can be broken along the step (5) by pulling the cutting tool (6) from the side end portion. The contents can be taken out by expanding the opening end of the heavy bag by expanding the opening.

The heavy bag using the plastic film of the present invention may be colored to such an extent that part or all of the heavy bag blocks direct sunlight. The color of coloring is not particularly limited, but white, milky white or the like that reflects sunlight is preferable. The cutting tool (6) used in the present invention is for cutting the overtape by providing an overtape (2), which plays a role of sealing the end opening of the heavy bag, along the bent step (5). It is preferable to use a material having a tensile strength larger than at least the tear strength of the overtape (2), and a tape made of a synthetic resin such as polyethylene or polypropylene or a cotton thread is used.

The overtape (2) used in the present invention
Is intended to seal the folded portion of the heavy bag, that is, the folded step portion (5), so that the folded portion is prevented from opening by bonding. As a material of the overtape (2), any material can be used as long as it can be bonded to the trunk portion (1) of the heavy bag, and usually, kraft paper or processed paper obtained by laminating a synthetic resin film on kraft paper is used. Since the sealing strength depends on the adhesive strength of the overtape (2) and the strength of the material, two layers of the overtape (2) are stacked so that the overtape (2) is not opened during transportation and handling, or the surface is waterproof. It is preferable to prevent the strength from decreasing by applying a treatment, for example, a synthetic resin coating or lamination.

FIGS. 2 and 3 are views showing a method of folding a heavy bag according to the present invention. At least one end opening is folded in a width of 1 cm to 4 cm in parallel with the opening end (4) in a closed state as shown in FIG. At this time, the reason why the thickness was set to 1 cm or more was that the plastic heavy bag for nitrate oil explosives had an
It is because strength cannot be maintained by bending with a width of less than cm.
The reason why the width is set to 4 cm or less is that even if a width larger than 4 cm is provided, the cost increases. Next, as shown in FIG. 3, the sheet is further bent with the open end (4) inside.

FIG. 1 shows a state after the heavy bag is sealed. After bending twice or more, the overtape (2) is adhered from the opposite surface to the bent surface with the cutting tool (6) so that the cutting tool (6) is located at the bending step (5). 4 to 6 show cross-sectional views in a state after sealing. FIG. 4 shows the case of bending twice.
FIG. 5 and FIG. 6 show the case of three-fold bending. All are bent so that the open end (4) does not come to the outer surface, so that the open end does not contact the overtape (2). This is because when the opening end (4) comes to the outer surface, even if the overtape (2) is cut by the cutting tool (6) at the bending step portion (5), the opening end (4) for taking out the nitrate oil explosive is used. ) Is difficult to open. Here, the bent length of the overtape (2) is drawn to be the same length on the front and back sides, but it is not necessary to make the same. However,
It is preferable to provide at least 1 cm or more for the torso adhesive surface (7) below the bent step (5). 1c
If it is less than m, the sealing strength of the bag is weak, and when the bag is dropped during handling, the bag may be opened and the explosive nitrate may spill. Also, bending twice or more is a problem that in the case of one-fold bending, the nitrate explosive reaches the open end (4) during transportation, weakens the adhesive strength of the overtape (2), and causes the oil to leach out of the bag. Because there is.

FIG. 7 shows a case where the cutting tool (6) and the overtape (2) of FIG. 1 are longer than the width of the heavy bag and have ears (8). Due to the presence of the ears (8), it is easy to hold at the time of handling at a consumer site and the like, and it can be hermetically sealed by bonding to prevent water intrusion, moisture absorption, etc. from the particularly folded both ends of the heavy bag. It has the advantage that. In that case, if there is ear (8) more than 1 cm, it is easy to hold,
Adhesion for sealing is also possible. Preferably, it is 3 cm to 5 cm.

FIG. 8 shows an adhesive surface (9) for sealing. The entire surface of the overtape (2) may be adhered, but there is no need to adhere to the outermost end, and sealing can be achieved by partially adhering at least parallel to the edge of the heavy bag of the ear (8). As a result, solidification of the nitrate oil explosive due to intrusion of water and moisture absorption and deterioration of the quality can be prevented. FIG. 9 shows the outermost end of the overtape (2) with ears (8), but with cuts (10) on both sides along the cutting implement (6). By making a cut (10), it becomes easier to operate the cutting tool (6). This cut (1
0) is preferably at least 5 mm or more, more preferably 1 cm to 2 cm. In addition, it is preferable in operation that the portion of the cut (10) is not bonded. Further, even when the ear portion is not provided as shown in FIG. Hereinafter, the present invention will be described with reference to examples.

[0017]

Example 1 A tensile strength was 10 MPa according to a measuring method according to JISZ1702, a thickness was 200 μm, and JISZ1702 was used.
A polyethylene film having an oil resistance of 30 hours measured according to No. 1515 was used as the body (1). The sealing method was the method shown in FIG. The bending width is 3cm, and it is bent twice, and the cutting tool (6) has a strong 9.5k.
g of polypropylene stretched tape, and two pieces of kraft paper having a tear strength of 117 g and a weft of 156 g were used as the overtape (2). Over tape (2)
Was 12 cm in width, and was sandwiched by an adhesive so as to be 6 cm on each of the opposite surface and the bent surface. Ten such heavy bags were prepared, and ten workers at the blasting site opened one bag at a time. All 10 were able to open and there was no need to use scissors.

Next, an ammonium nitrate explosive is put in this heavy bag,
The strength of the bag was examined. The test was carried out according to the Japanese Industrial Standards "Drop test method for heavy bags", but no bag breakage was observed even after dropping 10 times. Furthermore, a 200 kg load was applied on the bag and left for 30 days, but no solidification or exudation of the oil agent was observed. After that, the empty heavy bag was discarded, but there was no need for separation and it was good.

[0019]

EXAMPLE 2 Ten heavy bags were prepared in the same manner as in Example 1 except that ears (8) were provided at both ends of the heavy bags. The heavy bags were opened by 10 workers one by one. All ten people could open the bag more easily than the bag of Example 1.
After that, the empty heavy bag was discarded, but there was no need for separation and it was good.

[0020]

Example 3 In the same heavy bag as in Example 2, cuts (10) of 1 cm were made above and below the cutting tool (6) at the end of the overtape (2). Ten workers were asked to open one heavy bag at a time. It can be opened by pulling the cutting tool (6) at the part where the cut (10) is inserted.
All zero persons could open the bag more easily than the bag of Example 2. After that, the empty heavy bag was discarded, but there was no need for separation and it was good.

[0021]

Example 4 A JISZ1 sheet having a thickness of 70 μm and a tensile strength of 100 MPa measured according to JISZ1702.
The same heavy bag as in Example 3 was used except that a milky white colored polyethylene / nylon composite film having an oil resistance of 40 hours measured according to 515 was used as the body (1).
I made a bag. The heavy bags were opened by 10 workers one by one. After that, the empty heavy bag was discarded, but there was no need for separation and it was good.

[0022]

Example 5 Ten heavy bags were prepared in the same manner as in Example 1 except that imidazoline as an antistatic agent was kneaded into polyethylene. The measured surface resistivity was 10 ¹⁰ Ω. The heavy bags were opened by 10 workers one by one.
All ten were able to easily open. After that, the empty heavy bag was discarded, but there was no need for separation and it was good.

[0023]

Example 6 Ten heavy bags were made in the same manner as in Example 1 except that a biodegradable plastic film manufactured by Showa Kogaku KK under the trade name of Bionole was used. The heavy bags were opened by 10 workers one by one. Example 1 for all 10 persons
It was easier to open than the bag. After that, when the empty heavy bag was discarded, it was buried in the soil for 6 months. As a result, the prototype was almost lost and the biodegradability was good.

[0024]

COMPARATIVE EXAMPLE 1 As shown in FIG. 10, a kraft paper overtape (2) was applied to the body (1) of a heavy bag and sewed with a sewing machine to make 10 bags. When this was opened by ten workers, two of the ten workers could not unscrew the sewing thread (3) and had to use scissors. Then, at the time of disposal, plastic and kraft paper had to be separated, which was a major problem.

[0025]

Comparative Example 2 Plastic film is JISZ1702
10 heavy bags were prepared in the same manner as in Example 1 except that the tensile strength was 4 MPa measured according to the method described in Example 1. When ten workers opened this heavy bag one by one, there were many opinions that the handleability was poor.

[0026]

Comparative Example 3 Plastic film is JISZ1702
Except for using nylon having a tensile strength of 110 MPa measured according to the method described in Example 1, 10 heavy bags were prepared in the same manner as in Example 1. The heavy bags were opened by 10 workers one by one. All ten were able to easily open.
However, this heavy bag was expensive and was not practical.

[0027]

The heavy bag of the present invention is a plastic heavy bag for explosives having a nitric acid oil which has easy opening properties and is easy to dispose. In addition, no leaching of the oil agent during storage is observed, the strength of the bag does not decrease, and no external moisture is absorbed to solidify.

[Brief description of the drawings]

FIG. 1 is an explanatory view of one sealing portion of a heavy bag according to the present invention.

FIG. 2 is an explanatory diagram showing a form of a bent portion of the heavy bag of the present invention.

FIG. 3 is an explanatory view showing a form of a bent portion of the heavy bag of the present invention.

FIG. 4 is an explanatory view showing a form of a bent portion of the heavy bag of the present invention.

FIG. 5 is an explanatory view showing a form of a bent portion of the heavy bag of the present invention.

FIG. 6 is an explanatory view showing a form of a bent portion of the heavy bag of the present invention.

FIG. 7 is an explanatory view of a heavy bag according to the present invention having one sealing portion with an ear portion.

FIG. 8 is an explanatory view showing an adhesive surface for sealing.

FIG. 9 is an explanatory diagram showing the outermost end of an overtape having an ear.

FIG. 10 is an explanatory view of a heavy bag created by sewing with a sewing thread as a comparative example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Body part 2 Overtape 3 Sewing thread 4 Open end 5 Bending step part 6 Cutting tool 7 Body adhesion surface 8 Ear part 9 Adhesion surface 10 Cut

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3E064 AC30 BA26 BA30 BA35 BA36 BA37 BB03 BC04 BC05 BC20 EA30 FA06 HN04 HP03

Claims (7)

[Claims] In a double bag comprising a body having a tubular structure and a sealing portion, the body (1) is made of only a plastic film, and each end is aligned at an open end (4). The at least one sealing portion is bent at least twice with the open end (4) inside, and the open end (4)
Is a bent portion not in contact with the overtape (2),
And a stepped portion (5) formed between the bent portion overlapped by the bending and the body portion (1) not overlapped, and a cutting tool for cutting overtape arranged along the stepped portion (5). (6) and a plastic weight for a nitrate oil explosive, characterized by having an overtape (2) coated so as to sandwich the entire front and back surfaces of the sealing portion, the entire surface being adhered to the body surface. bag. 2. At least one end of the cutting tool (6) and the overtape (2) has an ear (8) extending outward from an end of the bag, and a part of the ear (8). The plastic heavy bag for an ammonium nitrate explosive according to claim 1, wherein is a bonded body of the cutting tool (6) and the overtape (2). 3. The explosive for nitrate oil explosives according to claim 1, wherein a part of the ear (8) has a cut (10) provided along the cutting tool (6). Plastic heavy bag. 4. The plastic heavy bag for an ammonium nitrate explosive according to claim 1, wherein a part or all of the plastic film has at least one of oil resistance and antistatic property. 5. The plastic film has a tensile strength of 5M.
The plastic heavy bag for an ammonium nitrate explosive according to claim 4, wherein the pressure is from Pa to 100 MPa. 6. The heavy plastic bag for an ammonium nitrate explosive according to claim 4, wherein the plastic film has biodegradability. 7. The plastic heavy bag for an ammonium nitrate explosive according to claim 4, wherein a part or the whole of the heavy bag is colored so as to block direct sunlight.