JP2009062090A - Inner bag used for outer container, its manufacturing process, and outer container using the inner bag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inner bag for storing contents which is used for an outer container such as a container or a drum can or the like and which can prevent leakage of a content liquid certainly and which is manufactured at a low cost and easily and has sufficient strength. <P>SOLUTION: The inner bag 20 for storing contents which is used for the outer container such as a container or a drum, is manufactured into a bag using two or more films or sheets which are in a blocking state. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an interior bag for storing contents such as liquid or powder used in an exterior container such as a container or a drum can, and also relates to an exterior container such as a container or a drum can containing the interior bag.

  When storing or transporting or storing contents such as liquid or powder in an outer container that maintains a fixed shape such as a drum can, a pail can, or a container, it is mounted inside the container and the contents are stored inside it. Synthetic resin interior bags are used for storage and transportation.

  This interior bag is a bag made by welding a bottom film or sheet and a body film or sheet of a container made of a thermoplastic resin (for example, refer to Patent Document 1), or a cylindrical body portion having a bottom. A bag made by overlapping upper end openings (for example, see Patent Document 2), or one end of a cylindrical body of a synthetic resin film or sheet is sealed and the other end is tied up with a seal. Various types of devices have been proposed (for example, see Patent Document 3).

  In addition, the top plate with the tube mouth on the upper end side of the tubular body obtained by inflation molding and the bottom plate with the discharge port on the lower end side are integrated or welded in a separate process to form a closed bag body. The present inventor has proposed a synthetic resin bag manufacturing method in which the welding process can be performed in one step as a synthetic resin bag manufacturing method in which the bottom plate and the top plate are welded to the upper and lower ends of the cylindrical body. (For example, see Patent Document 4).

In addition, as an interior bag used for a container outer container having a discharge cylinder at the lower part, in order to fit into the rigid discharge cylinder of the container outer container or to attach a nozzle portion communicating with the inner bag to this discharge cylinder A hole provided in the bottom portion of the interior bag is flexible while retaining its shape, and a short cylindrical discharge port having a collar portion at one end is used as an interior bag by using the collar portion as a retaining stopper from the interior bag body. Some are provided in an integrated manner (for example, see Patent Document 5).
JP 2001-219965 A JP 2003-335366 A JP 2002-347839 A Japanese Patent No. 3723540 JP 2005-59934 A

  In any type, the inner bag is damaged or cut when it is impacted, rubbed, scratched, etc. during transportation, and if the contents leak from it, an outer container such as a container or drum can is used. Corrosion occurs and the contents are contaminated with impurities. In particular, in the case where the content is an organic solvent, paint, or the like that is extremely hate to be contaminated with impurities, the contamination causes a serious problem.

  For this purpose, it is conceivable to make the film or sheet made of synthetic resin thick and to have sufficient strength. However, this interior bag is largely used in a so-called one-way, which is discarded after use from the viewpoint of the quality control of the contents. It is uneconomical because it is part.

  It has also been proposed to reduce the strength shortage by changing the number of films or sheets from one to two (Patent Document 1). In this case, when two sheets of one sheet are stacked, the inner bag and the outer It is necessary to align the size of the bag accurately, and it is never easy to store the inner bag neatly stacked on the outer bag, and it may be damaged by rubbing etc. during bag manufacture or after storing the contents. Prone to problems.

  When making a bag in the form of a double-layer film or sheet, slipping between the two-layer film or sheet becomes a problem. May be formed.

  Further, even when the film or sheet satisfies various conditions such as strength and impact resistance, when forming the bag body, like the interior bag shown in Patent Document 4 or Patent Document 5, the film or sheet When sealing a bag, or attaching a discharge port, adhesion (seal) between synthetic resins is necessary, and in the seal part between these synthetic resins, the seal is insufficient, or There was an accident in which the sealed part leaked due to the seal part being attacked by chemicals or the like as the stored object.

  FIG. 16 is an enlarged cross-sectional view of a portion where a sealing film or sheet for sealing the inner bag 41 or the like is sealed by welding. When force is applied due to the weight or internal pressure of the stored item 10, As a result, the portion 10 where the films or sheets 42 are sealed to each other (welding portion 43) is pushed and spread, and as a result, the stored item 10 soaks into the welding portion 43 having a reduced width dimension, and as shown by the dotted arrow in the figure, the outside. There is a risk of exposure.

  FIG. 17 is an enlarged cross-sectional view of a seal portion by welding in which the periphery of the bottom plate 44 is bonded to the periphery of the end portion of the cylindrical body 45 constituting the interior bag having the same structure as that shown in Patent Document 4. The bottom plate 44 is sealed at its periphery by the cylindrical body 43 and the welded portion 46. If the welded portion 46 is insufficiently welded or if there is a portion with a small width dimension, it is stored. Due to the weight or internal pressure of the object 10, the stored object 10 may permeate into the welded portion 46 and be exposed to the outside as indicated by the dotted arrow in the figure.

  Moreover, as an outlet of the interior bag used for the container exterior container of Patent Document 5, as shown in FIG. 18 (A), a hole 52 is formed in the bottom plate 51 of a normal flexible interior bag, and the hole A short cylindrical discharge port 53 with a flange 54 is protruded from the inner side to 52 and is prevented from coming off at the flange 54 and joined by a welded portion 55 to the bottom plate 51.

  By the way, when the liquid container is stored in the interior bag used for the container exterior container, the discharge port 53 is located below the interior bag, and therefore, the welded portion 55 that is a joint portion between the flange portion 54 and the bottom plate 51 of the interior bag. The osmotic pressure with the weight of the whole liquid added is applied to the liquid, and the liquid permeates, so that the flange portion 54 is peeled from the bottom plate 51, and the welding portion 55 which is not so wide is peeled off. The liquid that is the stored item may leak out from the portion (see FIG. 18B).

  Further, even if the welded portion 55 does not peel off, the width of the welded portion 55 is small, so that the liquid as the stored material penetrates into this portion and leaks to the outside, and gas barrier properties are required. In the case of stored items, even if the inner bag body has a double structure or the like and there is no problem in gas barrier properties, if the welded portion 55 of the discharge port 53 is peeled off, the outside air can easily enter the inner bag, May be exposed to air.

  In this way, depending on the nature of the stored item, even if the strength of the inner bag body is improved and the container bag is not damaged, the container outer container may leak due to leakage of the stored item from the seal part of the discharge port attached to the inner bag. The inner wall may be contaminated or the air shielding of the stored items may be insufficient, and even if an interior bag with improved body strength, solvent resistance, moisture resistance, and gas barrier properties is used, its significance will be lost. It was sometimes.

  The present inventors have intensively studied to obtain an interior bag having sufficient strength, easy to make bags and excellent in economy, and can reliably prevent leakage of the internal solution even in liquid storage. An object of the present invention is to provide a content storage interior bag having sufficient strength easily at low cost and an exterior container such as a container or a drum can using the same.

  In addition, an object of the present invention is to provide an interior bag capable of completely preventing accidents such as leakage, even if it has a portion sealed by welding or the like, without leakage from the sealed portion.

  The invention of claim 1 for achieving the above object is an internal bag for containing contents used for an external container such as a container or a drum can, and is made using two or more films or sheets in a blocking state. This is an interior bag that uses a bag structure.

  According to a second aspect of the present invention, there is provided an inner bag used in the outer container according to the first aspect, wherein the inner surface of the cylindrical film or sheet formed by inflation molding is overlapped to form a blocking film or sheet. Uses a bag-made configuration.

  The invention according to claim 3 is the interior bag used for the exterior container according to claim 2, wherein the film or sheet used for bag making is formed by stacking the inner layers of the multilayer tubular film or sheet obtained by multilayer inflation molding. The structure which is the film or sheet made into the blocking state is adopted.

  In the present invention, examples of the outer container include a container and a drum can, but the outer container is not limited thereto, and includes a pail can and other various containers, and the size thereof is not limited. Moreover, as long as it maintains a fixed shape, various materials such as metal, synthetic resin, wood, etc., and various coated surfaces are applicable regardless of the material.

  Moreover, as an interior bag, if it is a bag-like thing which has the flexibility which can be accommodated in the said exterior container, the thing which tied the film or sheet | seat cylindrically and tied one side (ball binding), a cylindrical film or a sheet | seat The end portion may be sealed by welding or the like, or a bottom plate or top plate as a separate member may be connected to form a bag, and the material and configuration thereof are not limited.

  Usually, in the processing of a film or sheet, the blocking state is an undesirable phenomenon. Therefore, in order to prevent the blocking state, a small amount of talc or the like is sprayed on the surface of the film or sheet immediately after manufacturing, or blocking is prevented. In contrast, it is normal to add an agent or a slip agent, but the present invention is characterized in that the blocking state can be used effectively.

  According to the interior bag of the present invention, two or two or more films or sheets in a blocking state are left as they are, preferably a film in a blocking state by overlapping the inner surfaces of a cylindrical film or sheet by multilayer inflation molding. Or use a sheet.

  Here, the term “blocking” is a general term also in the field of film or sheet molding and processing, but “Practical Plastic Glossary” (published by Plastics Age Co., Ltd., edited by Osaka City Industrial Research Institute). , Revised in September 1989, 3rd edition), “When plastic or rubber films or sheets are stacked, they may adhere to each other and cannot be easily peeled off. This is called blocking.” It is as it is.

  According to a fourth aspect of the present invention, in the inner bag used for the outer container according to any one of the first to third aspects, one opening of the cylindrical body portion is sealed with a bottom plate to form a bag shape. Adopts a structure in which two end plates are welded with the end portion of the cylindrical body sandwiched between both bottom plates, and air is sealed between both bottom plates.

  The invention of claim 5 is a method of manufacturing an interior bag used for the exterior container of claim 4 above, wherein the end of the cylindrical body is placed on the first bottom plate placed on the saddle bed. A structure is adopted in which the first bottom plate, the cylindrical body portion, and the second bottom plate are welded at the same time by stacking and further stacking the second bottom plate thereon and then heat-pressing with a scissors along the periphery of both bottom plates. .

  When two bottom plates are used and the cylindrical body is sandwiched between the bottom plates and welded, the liquid penetrates into each welded portion of the cylindrical body and the bottom plate due to the weight and internal pressure of the liquid stored in the interior bag. However, the leaked liquid stays in the gap between the bottom plates and must pass through the welded portion of the bottom plate and the cylindrical body portion again in order to go outside. In this case, it stays in the gap between the bottom plates. Since the liquid is not subjected to weight or internal pressure, there is a low possibility that the liquid will pass through the welded portion and leak to the outside.

  A sixth aspect of the present invention is the inner bag used in the outer container according to any one of the first to fourth aspects, wherein the short sleeve has a discharge port at a lower portion and a flange portion at one end. The collar part is sandwiched between two synthetic resin holding members with a hole in the center, and the discharge port protrudes from the hole provided in the interior bag body, along the circumferential shape of the collar part. A configuration is adopted in which the inner bag body and the discharge port are joined together with both the holding members by the weld portions formed continuously and the weld portions formed continuously along the outer periphery of the both holding members.

  The interior bag having the above structure using the two holding members and the two welded portions for joining the discharge port has the holding member and the inner bag body, the holding member and the holding member, with the weight and internal pressure of the liquid stored in the inner bag. Even if liquid permeates through each welded portion formed continuously between the holding member and the collar of the discharge port, the leaked liquid stays in the gap between the two holding members, and in order to go outside, the holding member again. And the inner bag body, the holding member and the welded portion of the discharge port collar, and in this case, the liquid remaining in the gap between the two holding members is not subjected to weight or internal pressure. The possibility of leaking outside through the section is low.

  The invention according to claim 7 is the interior bag used for the exterior container according to claim 6, wherein a short cylindrical reinforcing member having a flange portion at one end is provided in the discharge port from the inside of the interior bag body. Uses a structure that is welded and fixed in the inserted state.

  By the reinforcing member, it is possible to further prevent the liquid inside the discharge port from coming into direct contact with the welded portion between the flange portion of the discharge port and the upper holding member, and further prevent the liquid from leaking out.

  The invention according to claim 8 is an outer container such as a container or a drum can in which the inner bag according to any one of the first, second, third, fourth, sixth or seventh aspect is accommodated.

  The interior bag of this invention is used for an exterior container, and an effect arises, and the exterior container which accommodated these interior bags previously can exhibit the above-mentioned effect.

  In the inventions according to claims 1 to 3, the strength of the film or sheet is sufficient because the film or sheet in the blocking state is firmly attached so as not to be peeled off during the inner bag making process. There is no problem that the contents are leaked due to cutting and corroding an outer container such as a container / drum or the contents are contaminated with impurities.

  In addition, since it can be manufactured by a simple process, it is inexpensive, and the outer surface of the film or sheet is not sticky but slippery. There is also an effect that the processing is easy.

  According to the interior bag of the invention of claim 4, in addition to the above effect, since the end of the cylindrical body is sandwiched between the two bottom plates, it is welded between the stored item and the outside. In addition, there will be two welded parts, a welded part between the cylindrical body part and the upper bottom plate, and a welded part on the cylindrical body part and the lower part. By the presence of these two welded parts, for example, Even if the stored item melts the welded portion with a solvent, it takes time to invade the two welded portions to the outside due to the presence of two welded portions. Even if it exists, the storage period can be lengthened, and accidents in which stored items leak to the outside are extremely reduced.

  Also, in the unlikely event that the stored item leaks from the welded portion between the bottom plate at the top and the cylindrical body, there is air between the two bottom plates, so the leaked stored item moves within this gap, so the leakage at this point It is easy to confirm, and the effect that it becomes easy to notice before leaking to the outside also occurs.

  In addition, since air is sealed in the gap between the two bottom plates, this layer of air acts as a cushion to reduce the impact of falling items when the items are thrown in from the top. There is also an effect that the container is not damaged and the stored item itself is not damaged.

  According to the invention of claim 5, the conventional base bag and the base for manufacturing the interior bag are used as they are, and the first bottom plate, the end of the cylindrical body portion, and the second bottom plate are stacked in this order on the base. With the simple procedure of welding, it is possible to easily obtain the interior bag having the effect of the fourth aspect.

  According to the invention of claim 6, it does not permeate due to the weight or internal pressure of the liquid container from the seal part (welding part) that joins the interior bag body and the discharge port, which was a weak point in the past, and leaks to the outside. It is possible to effectively utilize the characteristics of the inner bag having enhanced strength, solvent resistance, moisture resistance, and gas barrier properties by blocking two or more layers of films or sheets.

  According to the invention of claim 7, in addition to the effect of the invention of claim 6, the reinforcing member covers the welded portion between the discharge port and the upper holding member. Leakage can be prevented.

  According to invention of Claim 8, these exterior containers have various effects which said interior bag has, for example, the intensity | strength of an interior bag is enough, a damage | wound and a piece are produced, the content leaks, and an exterior container is corroded. And the problem that the contents are contaminated with impurities mixed from the outside can be exhibited.

  Hereinafter, embodiments of the present invention will be described in more detail.

[First Embodiment]
The raw material film or sheet used for making the interior bag of the present invention is two or more films or sheets in a blocking state. Various resins can be used as long as they are thermoplastic resins. Polyolefins such as polyethylene, polypropylene, ethylene vinyl acetate copolymer, polyesters such as polyvinyl chloride, polystyrene, polyethylene terephthalate, polyamides, etc. Is mentioned.

  Two or more films or sheets in the blocking state of these thermoplastic resins are used to make a bag, but the two films or sheets may be different types of resins, A combination of the same resins may be used.

  A preferred method for obtaining a film or sheet in a blocking state is a method for obtaining a film or sheet in a blocking state by superimposing inner surfaces of cylindrical films or sheets formed by inflation molding. A cylindrical film or sheet obtained by inflation molding is used, and a film or sheet in which the inner side surfaces are overlapped with a pinch roller or the like to be in a blocking state can be easily obtained.

  However, when the roll is continuously rolled with a roller, the outer surfaces of the blown cylindrical film or sheet are in contact with each other, so that a blocking state is likely to occur here. In order to eliminate the problem even when a film or sheet in a blocking state is rolled, a multilayer cylindrical film or sheet in which the outer layer does not cause a blocking state by multilayer inflation molding is obtained, and the inner layer surfaces are pinched rollers. It is preferable to obtain a film or sheet which has been put into a blocking state by being overlapped with each other. Thereby, even if it rolls, it can handle without a problem and the trouble in the bag making process by the roll film or sheet | seat of a blocking state is eliminated.

  As the multilayer film or sheet, a two-layer structure consisting of an inner layer and an outer layer is sufficient, but an intermediate layer having three or more layers may be provided. In either case, the innermost layer of the tubular film or sheet is The materials are made to easily cause a blocking state, and the outermost layer is selected for its material or set for inflation molding so that they do not cause a blocking state.

  As the resin used for the inner layer, as described above, polyolefin such as polyethylene, polypropylene, ethylene vinyl acetate copolymer, polyester such as polyvinyl chloride, polystyrene, polyethylene terephthalate, polyamide, etc. can be used, and the outer layer can be used. It is a preferable embodiment to use an antiblocking agent or a slip agent blended therein.

  As the anti-blocking agent and the slip agent, known ones such as a high melting point wax, a long chain fatty acid amide, and a metal soap can be used.

  Another preferred embodiment is an embodiment in which a resin that easily causes a blocking phenomenon is used for the inner layer of multilayer inflation molding, and a resin that is less likely to cause a blocking phenomenon is used for the outer layer. The inner layer is preferably high-pressure low-density polyethylene, linear low-density polyethylene, high-density polyethylene, ethylene vinyl acetate copolymer, metallocene-based polyethylene or ethylene-α-olefin copolymer, or a mixture thereof. The thing which was done is mentioned. (As the α-olefin, an α-olefin having 3 to 8 carbon atoms such as propylene, 1-butene, 1-hexene and 1-octene is preferably exemplified.

Among these, an ethylene-α-olefin copolymer using a metallocene catalyst is particularly preferable. The ethylenically -α- olefin copolymer, but those commercially available known one can be used, inter alia density 0.88~0.92g / cm ^3, in particular those of 0.89~0.915g / cm ^3, Melt flow rate (190 ° C., load 2.16 kg) of 0.01 to 50 g / 10 min, especially 0.1 to 20 g / 10 min, molecular weight distribution (GPC measurement at Mw / Mn, column temperature 140 ° C.) Is preferably from 1.5 to 4.5, particularly preferably from 2 to 4. Preferable examples that satisfy these requirements include trade name Harmolex NF324A manufactured by Nippon Polyethylene Corporation.

  As the resin used as the outer layer with respect to the inner layer, a resin having lower adhesion than the inner layer resin and less likely to cause a blocking state is used. For example, a high melting point polypropylene resin, a high density high density polyethylene or It is also a preferred embodiment to apply a resin which does not cause a blocking state by blending an anti-blocking agent with the above-mentioned resins for the inner layer or other resins.

  As another preferred embodiment, it is effective to improve the bag making characteristics by providing a three-layer structure and providing an intermediate layer to increase the rigidity of the film or sheet. As an intermediate | middle layer, a high density polyethylene, a polypropylene, etc. are mentioned preferably.

  The resin of each layer has an anti-blocking agent, a slip agent, an antistatic agent, a lubricant, a neutralizing agent, an antioxidant, a light stabilizer, a weathering agent, a flame retardant, and a nucleating agent to the extent that the object of the present invention is not impaired. Additives such as pigments, colorants, fillers and foaming agents can be optionally blended.

  A multilayer tubular film or sheet formed by multilayer inflation molding is formed by laminating inner layers to form a laminated film or sheet. Preferably, the multilayer film or sheet is blocked during a series of inflation moldings, that is, during molding. That is, the inner layer resin and the outer layer resin are supplied to an inflation film molding machine equipped with an extruder, and are multilayer co-extruded from a circular die under continuous resin temperature extrusion conditions, cooled while being inflated with air pressure (usually air cooling), and continuously A cylindrical bubble-like multilayer film or sheet is formed, and the bubble-like multilayer film or sheet is sandwiched between a pair of pinch rolls and the inner layers are laminated and bonded together in a series of continuous processes. Since the surface of the laminated film or sheet is composed of an outer layer resin that hardly causes a blocking state, it can be easily rolled.

  In multi-layer inflation molding, it is inflated with air pressure as described above, followed by air cooling or water cooling, but cooling from the outside causes a cooling rate difference between the outer layer and the inner layer, but the height from the extrusion die to the upper pinch roller is increased. Increasing the difference between the inner and outer layers increases the cooling of the inner layer, and the inner layer is easily wound up by a pinch roller in a state where a blocking state is likely to occur. It is also possible to obtain a sheet.

  The thickness of the film or sheet before the blocking state is about 0.01 to 0.5 mm, preferably 0.02 to 0.3 mm, and the thickness of the laminated film or sheet after the blocking state is about 0.02 to 1 mm, Preferably it is 0.04-0.6 mm.

  Although this laminated film or sheet is used as an interior bag, various shapes can be adopted as the contents-accommodating interior bag of the outer container used for the container or drum can. This interior bag is formed by welding a bottom film or sheet of a container made of a thermoplastic resin and a body film or sheet as described in 1) Patent Document 1, and 2) in Patent Document 2. In this way, the bottom end of the cylindrical body portion is overlapped with the upper end opening, or 3) a seal portion in which one end of a cylindrical body made of synthetic resin as in Patent Document 3 is sealed is tied up. It can be applied to any type using a resin film or sheet.

  An outer container such as a container or a drum can containing the inner bag made in this way accommodates various liquids and powders and is used for transportation and storage.

[Second Embodiment]
The interior bag according to the second embodiment of the present invention has a shape in which a bottom plate is connected to a cylindrical body portion. If a method of forming the interior bag is described with reference to FIGS. Two bottom plates, a first bottom plate 1 and a second bottom plate 2, and a cylindrical body portion 3 serving as a main body are prepared.

  The first bottom plate 1, the second bottom plate 2, and the cylindrical body 3 are made of synthetic resin, and each synthetic resin is manufactured using two or two or more films or sheets in a blocking state, The material is not particularly limited as long as the material has strength, flexibility and flexibility suitable as an interior bag, and a known synthetic resin such as PE, PA, PET, EVAL (registered trademark) (EVOH), or the like is used. The cylindrical body 3 has a cylindrical diameter approximately the same as the diameters of the first bottom plate 1 and the second bottom plate 2.

  As these synthetic resins, an antistatic agent is used to prevent ignition due to the generation of static electricity when an ignitable solvent (liquid) such as toluene having an ignitability is added in accordance with the characteristics of the stored items. You may use what was added, or used what made the film or sheet | seat of two or more layers the blocking state in order to improve the intensity | strength and chemical-resistance of a main body.

  First, the first bottom plate 1 is placed on the disk-shaped gantry 4 shown in FIG. 1, and further, the cylindrical body 3 is overlapped on the outer side of the gantry 4, and from the gantry 4 of the cylindrical body 3. The end projecting upward is folded and overlapped around the first bottom plate 1 inside the base 4 (FIG. 2A).

  The 2nd bottom plate 2 is piled up on the edge part of the 1st bottom plate 1 and the cylindrical trunk | drum 3 which were accumulated on the stand 4 so that it may become the same position as the 1st bottom plate 1 (FIG.2 (B)).

  Next, a non-welded film or sheet 5 is stacked on the second bottom plate 2, and then non-welded to the overlapping portion of the periphery of the first bottom plate 1 and the second bottom plate 2 and the end of the cylindrical body 3. These synthetic resins are welded and bonded by heating the ridge 6 from above the film or sheet 5 (FIG. 2C).

  When the scissors 6 are moved along the periphery of the first bottom plate 1 and the second bottom plate 2 while being thermocompression bonded, the first welded portion 7 in which the periphery of the first bottom plate 1 and the end of the cylindrical body 3 are welded is formed. Similarly, the second welded portion 8 is formed by welding the end of the cylindrical barrel portion 3 and the periphery of the second bottom plate 2, and the cylindrical barrel portion 3, the first bottom plate 1 and the second bottom plate 2 are bonded and fixed. (FIG. 2D).

  FIG. 3 shows an interior bag 9 made up of the first bottom plate 1, the second bottom plate 2, and the cylindrical body portion 3 obtained by the above manufacturing method, and the opening side of the cylindrical body portion 3 as necessary. In addition, a top plate (not shown) with a storage opening may be provided.

  Since the end portion of the cylindrical body 3 is sandwiched and welded around the first bottom plate 1 and the second bottom plate 2 of the interior bag 9, a gap is generated between the first bottom plate 1 and the second bottom plate 2. The air at the time of manufacture is in a sealed state.

  When the inner bag 9 is stored in the outer container with the bottom plate facing down, and the stored item is dropped from the upper side and stored, the stored item hits the bottom plate due to its weight and gives an impact. The air enclosed in the gap between the bottom plates 2 serves as a cushion, and absorbs the impact of the fall of the stored items.

  For this reason, even if the stored item is a heavy granular material, the outer container will not be damaged by the impact of dropping during storage, and if the stored item is a granular material that is prone to breakage, the stored item will drop. Thus, even if it hits the first bottom plate 1, the air layer between it and the second bottom plate 2 below becomes a cushion, and damage to the stored items is prevented.

  FIG. 4 is an enlarged view of the interior bag 9 around the first bottom plate 1 and the second bottom plate 2 and in the vicinity of the first welded portion 7 and the second welded portion 8. Therefore, the penetration of the liquid storage 10 to the welded portion is strong, and there is an insufficiently welded portion in the first welded portion 7 where the first bottom plate 1 and the cylindrical body portion 3 are joined. If there is a portion with a small welding width dimension, the stored item 10 may leak out as indicated by the dotted arrow in the figure.

  However, in order to leak the stored item 10 that has passed through the first welded portion 7 to the outside of the interior bag 9, the second welded portion 8 in which the cylindrical body portion 3 and the second bottom plate 2 are joined is further provided. The presence of the second welded portion 8 prevents leakage of the stored item 10.

  As described above, the welded portion is provided in the two-stage structure of the first welded portion 7 and the second welded portion 8 between the inside and the outside of the interior bag 9 in which the stored item 10 is stored. Thus, it is possible to prevent the leakage accident to the outside of 10 from becoming almost zero.

  Note that when the stored item 10 leaks from the first welded portion 7, a space is generated due to the air existing in the gap between the first bottom plate 1 and the second bottom plate 2, and the stored item 10 is within this space. When the outer container is transparent or the stored item is transparent, it is easy to notice before an accident that passes through the second welded portion 8 and finally leaks to the outside.

  Since the interior bag 9 of the second embodiment is a laminated body having a structure of two or more layers in a blocking state, it is excellent in strength and solvent resistance, and is a defect of the interior bag manufactured using welding. There is no leakage from a certain seal part (first welded part 7, second welded part 8), and if a synthetic resin to which an antistatic agent has been added is further used, no static electricity is generated and there is a risk of explosion due to ignition. It can be used for storage of the solvent.

  In addition, in this 2nd Embodiment, although the bottom plate was circular shape, it is not limited to this, It is also possible to make it square shape and polygonal shape according to the shape of an exterior container.

[Third Embodiment]
FIG. 5 shows a process for producing a gusset-shaped interior bag when the exterior container is a container container as a third embodiment. First, a welded property of PE or the like formed on a tubular film or sheet by inflation molding. A synthetic resin film or sheet 21 having a two-layer structure in a blocking state is prepared by laminating a film or sheet made of material with a pinch roller or the like so that the inner side surfaces are overlapped and flattened (FIG. 5 ( A)).

  Next, a synthetic resin film or sheet 22 having a structure in which one surface is a weldable material and the other surface is a non-weldable material is prepared. Good.

  Two sheets of this synthetic resin film or sheet 22 are prepared, folded in half with the surface made of the non-weldable material 23 as a valley side, and on both sides of the synthetic resin film or sheet 21 with the folding side inward. Overlap (FIG. 5B).

  Furthermore, on the synthetic resin film or sheet 21 and the two synthetic resin films or sheets 22, the synthetic resin made of a welding material such as PE and obtained by the same manufacturing method as the synthetic resin film or sheet 21. The film or sheet 24 is stacked (FIG. 5C).

  FIG. 7 shows two synthetic resin films or sheets 22 on a synthetic resin film or sheet 21 made of a weldable material in the state shown in FIG. It is a disassembled perspective view explaining the state which bent and overlapped on the trough side, and also the state which laminated | stacked the synthetic resin film or sheet | seat 24 which consists of a weldable material on it further easily.

  Next, as shown in FIG. 6 (D), the synthetic resin film or sheet 21, the synthetic resin film or sheet 22, and the synthetic resin film or sheet 24 are stacked on the film or sheet laminate. These films or sheet laminates are welded and joined together by crimping and heating using a welding rod or the like along the welding line 26 continuously drawn along the outer shape of the shape.

  Further, the outer side along the welding line 26 is removed by cutting or the like to obtain a bag body. At this time, the welding line 26 is not welded along the side that becomes the filling port of the interior bag, but is welded at both ends. The portion sandwiched between the lines 26 becomes the filling port 27 (FIG. 6E).

  FIG. 8 is a perspective view of the bag body of FIG. 6 (E). As shown in FIG. 5 (C) and FIG. 7, the synthetic resin film or sheet 21 and the synthetic resin film or sheet 22 facing each other. The folded surface of the weldable material is welded and joined by a welding wire 26, and the synthetic resin film or sheet 22 of the folded outer surface of the weldable material and the synthetic resin film or sheet 24 are joined. Are welded and joined by the welding wire 26, but the inner side of the synthetic resin film or sheet 22 that is folded is made of the non-weldable material 23, so that joining by welding is not performed.

  Therefore, the welded portion welded along the weld line 26 includes a welded portion 28 that joins the synthetic resin film or sheet 21 and the synthetic resin film or sheet 22, and the synthetic resin film or sheet 24 and the synthetic resin film. Or the welding part 29 which joins the sheet | seat 22, and two welding parts exist (refer FIG.6 (D) (E), FIG.8, FIG.9).

  Next, the lowermost part of the bag constituted by the synthetic resin films or sheets 21, 22, and 24 is cut into a rectangular shape slightly smaller than the size of the bottom film or sheet member 19 described later, and an opening is provided. The opening is covered and closed with a bottom film or sheet member 19 made of a welding material having a rectangular shape slightly larger than the opening, and the discharge port 11 is joined to a hole 25 provided in the bottom film or sheet member 19. Then, the discharge port 11 is once closed, and in this state, when air is fed from the portion that is the upper unfilled filling port 27, the bag made of the synthetic resin film or sheets 21, 22, and 24 expands, As shown in FIG. 9, a container outer container inner bag 20 having a rectangular shape matching the inside of the container outer container is obtained.

  In this case, the synthetic resin film or sheet 22 forming a pair of opposite side surfaces is weldable on the inside and non-weldable material 23 on the outside, but welded with the interior bag 20 turned inside out. It can also be used with the portions 28 and 29 inside the interior bag 20, in which case the side surface made of the synthetic resin film or sheet 22 is the non-weldable material 23 on the inside and the weldable material on the outside. (Not shown).

  As shown in FIG. 9, in the interior bag 20 used for the container outer container of the finished product, an extendable nozzle member 30 housed in the discharge cylinder of the container outer container used communicates with the discharge port 11. Will be connected.

  In the embodiment described above, the synthetic resin film or sheet 22 having a two-layer structure of the weldable material and the non-weldable material is used by superimposing one by one on one side. The number of sheets 22 used is not limited to that of the above-described embodiment. For example, the sheets 22 may be welded after being stacked in a bellows shape on both sides so as to be two or more on one side.

  Next, the details of the structure for connecting the discharge port 11 to the hole 25 provided in the bottom film or sheet member 19 connected to the lower part of the inner bag 20 used for the container outer container, as shown in FIG. Like the conventional one, the discharge port 11 has a short cylindrical shape with both end portions penetrating, and a collar portion 12 is provided at one end, and the collar portion 12 is disposed inside an interior bag 20 used for a container exterior container. The discharge port 11 protrudes from the hole 25 of the bottom film or sheet member 19 and is fixed.

  First, a holder 13 having a disc shape made of a synthetic resin and having a hole through which the main body cylindrical body of the discharge port 11 passes in the center, and a disc shape made of a synthetic resin and penetrating the discharge port 11 in the center. A holding body 14 having a hole having the same size as the hole is prepared.

  Next, the holding body 13 is overlaid on the bottom film or sheet member 19, the hole provided in the holding body 13 is matched with the hole 25 of the bottom film or sheet member 19, and the interior of the container exterior container is used in the overlapping portion of the hole. By passing the cylindrical body of the discharge port 11 from the inside of the bag 20, the holding body 13 is sandwiched between the flange 12 and the bottom film or sheet member 19 in the discharge port 11.

  Next, the holding body 14 is further overlapped on the flange 12 of the discharge port 11 so that the hole provided in the holding body 14 and the hole of the discharge port 11 are aligned (see FIG. 10).

  Further, in this state, on the circumference along the flange 12 portion of the discharge port 11 and on the circumference along the outer circumference of the holding body 13 and the holding body 14, along the welding lines 15 and 16 shown in FIG. 12. A welding part is formed by continuous welding treatment by pressing and heating using a welding rod or the like.

  Along the inner welding line 15, a welded portion 17 a between the bottom film or sheet member 19 and the holding body 13, a welded portion 17 b between the holding body 13 and the flange 12, and a welded portion 17 c between the flange 12 and the holding body 14. A welded portion 18 a between the bottom film or sheet member 19 and the holding body 13 and a welded portion 18 b between the holding body 13 and the holding body 14 are formed along the outer welding line 16.

  Synthetic resins constituting the respective parts are welded and joined together by the respective welded portions 17a, 17b, 17c, 18a, and 18b formed in this circumferential shape and sealed at this portion, and the interior of the interior bag 20 used for the container exterior container The liquid container stored in the container will not leak out.

  By the way, as shown in FIG. 11, the inner bag 20 used for the container outer container and the bottom film or sheet member 19 are welded and connected at the welding portion 31, but the inner bag 20 used for the container outer container and the bottom portion are used. If the overlapping portion with the film or sheet member 19 is made large, the width of the welded portion 31 can be widened, and leakage of the liquid storage can be sufficiently prevented. A portion for fixing the frame to the bottom film or sheet member 19, in particular, a welded portion 17 c that welds the flange portion 12 of the discharge port 11 is restricted by the width of the flange portion 12 and does not have a sufficient width.

  However, even when the liquid penetrates the seal portion that fixes the discharge port 11 due to the internal pressure of the liquid stored in the interior bag 20 used for the container exterior container and leaks in a minute amount beyond the seal portion. Immediately no liquid leaks out of the interior bag 20 used for the container exterior container.

  This is because the liquid that has permeated and passed through the welded portion 18a or 18b, which is the outer seal portion, of the liquid stored in the inner bag 20 used for the container outer container is the bottom film or sheet member 19 and the holding body 13, respectively. However, in order for these liquids to leak further outside the bottom film or sheet member 19, they must pass through the welded portions 17a or 17b, respectively. .

  Further, the liquid that is in the gap with the holding body 14 along the upper surface of the flange portion 12 from the upper side of the discharge port 11 and penetrates the weld portion 17c that cannot take a width greater than the width of the flange portion 12 also causes the weld portion 18b to enter. In order to enter the gap between the holding body 13 and the holding body 14 and leak out to the outside of the bottom film or the sheet member 19 as in the case of the permeated liquid, the liquid must pass through the welded portion 17b.

  Due to the internal pressure of the liquid container, etc., the liquid container penetrates into the seal portions (welding portions 18a, 18b, 17c) of the respective attachment portions and leaks in a minute amount, so that the bottom film or sheet member 19 and the holding member 13 Even if the gap or the gap between the holding member 13 and the holding member 14 is entered, the liquid penetrates another sealing portion (welded portions 17a and 17b) in order to leak to the outside of the bottom film or sheet member 19. However, since the total weight and internal pressure of the stored liquid are not applied to the liquid that has permeated and passed through the first seal portion, it again penetrates the seal portion (welded portions 17a and 17b) to the outside. There is little risk of leakage.

  Although the holding members 13 and 14 used in this embodiment are disk-shaped, the present invention is not limited to this, and may be a polygonal shape such as a triangle, a quadrangle, or a rectangle.

  By using the interior bag used for the container exterior container having the above structure, the structure of the interior bag body has two or more layers, which is excellent in strength and solvent resistance against damage, and the stored item itself is not affected by the outside. In addition to being excellent in moisture resistance and gas barrier properties, it is possible to almost eliminate leakage of stored items from the sealing portion of the joint portion of the discharge port, which has been problematic in the past, and does not contaminate the inner wall of the container outer container It becomes an interior bag used for an optimal container exterior container for a container exterior container.

[Fourth Embodiment]
Next, the structure of the outlet shown in FIGS. 14 and 15 using the reinforcing member 32 shown in FIG. 13 in the interior bag 20 of the third embodiment will be described. The reinforcing member 32 is made of a hard material such as HDPE, for example. Thus, the main body cylinder portion having an outer diameter that can be accommodated inside the cylinder of the discharge port 11 is provided, and a flange portion 33 is provided at one end portion.

  As shown in FIG. 14, the reinforcing member 32 is used in such a manner that the main body cylindrical portion of the reinforcing member 32 is placed in the cylindrical portion of the discharge port 11 in a state where the flange portion 12 of the discharge port 11 is sandwiched between the holding bodies 13 and 14. Inserted into the interior, the flange 33 is overlaid on the holding body 14, and in this state, inserted into the bottom film of the interior bag 10 or the hole 5 of the sheet member 19.

  In this state, as shown in FIG. 15, on the circumference along the portion of the flange portion 12 of the discharge port 11 and on the circumference along the outer periphery of the flange portion 33 of the holding bodies 13 and 14 and the reinforcing member 32, 8 are bonded and heated using a welding rod or the like so as to be along the same lines as the welding lines 15 and 16 shown in FIG.

  Along the inner welding line, a welded portion 17a between the bottom film or sheet member 19 and the holding body 13, a welded portion 17b between the holding body 13 and the flange portion 12, a welded portion 17c between the flange portion 12 and the holding body 14, A welded portion 17d between the holding body 14 and the flange 33 is formed, and a welded portion 18a between the bottom film or sheet member 19 and the holding body 13 and a weld between the holding body 13 and the holding body 14 along the outer welding line. The welded portion 18c between the portion 18b and the holding body 14 and the flange portion 33 is formed.

  Furthermore, the front-end | tip part of the main body cylinder part of the reinforcement member 32 and the discharge port 11 are heated, and the welding part 34 is formed continuously.

  According to the above configuration, for example, in the structure of the third embodiment shown in FIG. 11, when the liquid stored in the welded portion 17 c penetrates and leaks into the welded portion 17 b immediately below, the liquid leaks to the outside. Whereas the portions where the welded portions 17c and 17b are located are most liable to leak liquid, in the structure shown in FIG. 15, the stored liquid must be passed through the welded portions 18c and 17d or the welded portion 34. Therefore, it is possible to prevent liquid leakage at the portion.

EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example and a comparative example, this invention is not limited by these.
In the following Examples 1 to 10 and Comparative Examples 1 to 4, the resins used for inflation molding are as follows.

mLLDPE-A: Ethylene-α-olefin copolymer “Harmolex NF324A” by metallocene catalyst manufactured by Nippon Polyethylene Co., Ltd., MFR = 1.0 g / 10 min, density = 0.906 g / cm ³
mLLDPE I A2: 100 parts by weight of the above-mentioned LDLDPE-A is mixed with 1 part by weight of silica as an anti-blocking agent (“Silicia 350” manufactured by Fuji Lisilia Chemical Co., Ltd. After blending with a mixer, it was melt kneaded and pelletized with a φ40 mm single screw extruder (cylinder and die temperature set at 200 ° C.).
mLLDPE-B: “Harmolex NF444A” manufactured by Nippon Polyethylene Co., Ltd., MFR = 2.0 g / 10 min, density = 0.912 g / cm ³
mLLDPE-B2: 1 part by weight of silica (“Silysia 350” manufactured by Fuji Lisilia Chemical Co., Ltd.) is added to 100 parts by weight of the above-mentioned mLLDPE-B. The blending method is the same as mLLDPE-A2.
HDPE: High density polyethylene “Novatech HD HY443” manufactured by Nippon Polyethylene Co., Ltd., MFR = 1.1 g / 10 min, density 0.956 g / cm ³ .
EVA: ethylene vinyl acetate copolymer “Novatech EVA LV430” manufactured by Nippon Polyethylene Co., Ltd., MFR = 1.0 g / 10 min.
LDPE-2: Low Density Polyethylene “Novatec LD LF441B” manufactured by Nippon Polyethylene Co., Ltd., MFR = 2.0 g / 10 min, density = 0.924 g / cm ³ 100 parts by weight of silica as an antiblocking agent (Fuji Lisilia Chemical 1 part by weight of “Silicia 350” manufactured by Co., Ltd. is blended in the same manner as mLLDPE-A2.
PP: Polypropylene “Novatec PP EG7F” manufactured by Nippon Polypro Co., Ltd., MFR = 1.3 g / 10 min (230 ° C.), density = 0.900 g / cm ³

[Examples 1-5 and Comparative Examples 1-2]
Both inner layer and outer layer are φ50mm single screw extruder, two-type two-layer cylindrical die with die diameter φ75mm and lip gap 2.5mm, extruder set temperature = 180 ° C, adapter set temperature = 190 ° C, die set temperature = 190 Air-cooled inflation molding at ℃, Oshiyama resin amount = 30 kg / h (inner layer and outer layer combined), inner layer / outer layer ratio = 1/1, film thickness 60 µm (120 µm after blocking) and film width 400 mm It was. The height from the die upper surface to the first pinch roll was 5.0 m, and the air cylinder pressure of the first pinch roll was 5.5 kgf / cm ² .

[Examples 6 to 10 and Comparative Examples 3 to 4]
Inner layer, intermediate layer, and outer layer are φ40mm single screw extruder, three-type three-layer cylindrical die with die diameter φ100mm and lip gap 2.5mm, extruder set temperature = 180 ° C, adapter set temperature = 190 ° C, die set temperature = 190 ° C., Extruded resin amount = 20 kg / h (inner layer / intermediate layer / outer layer combined), inner layer / intermediate layer / outer layer = 1/2/1, film thickness 60 μm (120 μm after blocking) and film width 400 mm Air-cooled inflation molding was performed. The height from the die upper surface to the first pinch roll was 6.0 m, and the air cylinder pressure of the first pinch roll was 5.0 kgf / cm ² .

The strength, pinhole resistance, and the like of the above-mentioned blocked inner bag film were evaluated.
The evaluation method is as follows.

[Peel strength]
In order to measure the blocking force between the inner layers of an inflation molded film, the film is cut into a strip of 2 cm width in the longitudinal direction (MD) of the film, and the shear peel strength of the blocking state part (10 cm ^{2 in} area) for a length of 5 cm Was measured with a tensile tester. The test was conducted in a temperature-controlled room at a temperature of 23 ° C. and a humidity of 50%. The speed of the tensile test was 300 mm / min, and the maximum strength until peeling was defined as “peel strength”.

[Bag making aptitude]
In the blocked state, two sheets of film were stacked, and a 400 mm square pouch-shaped interior bag was formed using an impulse sealer around the periphery (four sides). The state of the interior bag was observed, and the wrinkle generation state of the bag and the wrinkle generation state of the heat seal part were visually confirmed.

[Film Impact]
The measurement was performed in a temperature-controlled room at a test temperature of 23 ° C. and a humidity of 50% while still in the blocked state. A “film impact tester” manufactured by Toyo Seiki Seisakusho Co., Ltd. was used, and a “1/2 inch hemispherical” head was used at the punching tip. The number of tests N was 12 times, and the film impact was determined by the arithmetic average of 10 points excluding the maximum value and the minimum value.

[Pinhole resistance]
Using a Gelboflex test apparatus manufactured by Tester Sangyo Co., Ltd., pinholes after 3000 repetitions at 23 ° C. were measured. For the measurement, a blocked film was used, and the size was 20 cm wide × 30 cm long. The measurement was performed 3 times each in the longitudinal direction (MD) and the width direction (TD) of the film, and the average value of 6 measurements was obtained.

  On the other hand, two non-blocking films were stacked to have the same thickness, and as a comparative example, physical properties were compared with the examples, and the examples and comparative examples were compared.

It is front sectional drawing which shows the manufacturing method of the interior bag of 2nd Embodiment of this invention. (A), (B), (C), and (D) are partially enlarged sectional views showing the manufacturing method of the present invention. It is front sectional drawing which shows the interior bag of 2nd Embodiment of this invention. It is a partially expanded sectional view which shows the principal part of the interior bag of 2nd Embodiment of this invention. (A), (B), and (C) are the top view and front view which show the manufacturing process of the interior bag of 3rd Embodiment of this invention. (D) (E) is the top view and front view which show the manufacturing process of the interior bag of 3rd Embodiment of this invention. It is a one part disassembled perspective view of the manufacturing process of the interior bag of 3rd Embodiment of this invention. It is a one part perspective view of the manufacturing process of the interior bag of 3rd Embodiment of this invention. It is a perspective view of the interior bag of 3rd Embodiment of this invention. It is front sectional drawing which shows the structure of the discharge port of the interior bag of 3rd Embodiment of this invention. It is front sectional drawing which shows the discharge port of the interior bag of 3rd Embodiment of this invention. It is a top view which shows the discharge port of the interior bag of 3rd Embodiment of this invention. It is a perspective view of the reinforcement member used for the interior bag of 4th Embodiment to this invention. It is front sectional drawing which shows the structure of the discharge port of the interior bag of 4th Embodiment of this invention. It is front sectional drawing which shows the discharge port of the interior bag of 4th Embodiment of this invention. It is a partially expanded sectional view which shows the principal part of the conventional interior bag. It is a partially expanded sectional view which shows the principal part of the conventional interior bag. (A) (B) is front sectional drawing which shows the structure of the discharge port of the conventional interior bag.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st bottom plate 2 2nd bottom plate 3 Cylindrical trunk | drum 4 Casing base 5 Non-welding film or sheet 6 7 First welding part 8 Second welding part 9 Inner bag 10 Stored goods 11 Discharge port 12 Butt part 13 Holding body 14 Holder 15 Welding wire 16 Welding wires 17a, 17b, 17c Welding portions 18a, 18b Welding portion 19 Bottom film or sheet member 20 Inner bag 21 Synthetic resin film or sheet 22 Synthetic resin film or sheet 23 Non-weldable material 24 Synthesis Resin film or sheet 25 Hole 26 Welding wire 27 Filling port 28 Welding part 29 Welding part 30 Nozzle member 31 Welding part 32 Reinforcing member 33 Gutter part 34 Welding part

Claims (8)

  An interior bag for containing contents used in an exterior container such as a container or a drum can, the bag being made using two or more films or sheets in a blocking state, and used for the exterior container .   The inner bag used for the outer container according to claim 1, wherein the inner surface of the cylindrical film or sheet formed by inflation molding is overlapped to form a bag using the film or sheet in a blocking state. .   The exterior container according to claim 2, wherein the film or sheet used for bag making is a film or sheet obtained by stacking inner layers of a multilayer cylindrical film or sheet obtained by multilayer inflation molding to form a blocking state. Interior bag used for   One opening of the cylindrical body is sealed with a bottom plate to form a bag, and the two bottom plates are welded with the ends of the cylindrical body sandwiched between both bottom plates, and between the bottom plates Air is enclosed, The interior bag used for the exterior container of any one of Claim 1 thru | or 3 characterized by the above-mentioned.   A method of manufacturing an interior bag used for the exterior container according to claim 4, wherein the end of the cylindrical body is overlaid on the first bottom plate placed on the base, and further on An interior used for an exterior container, wherein the first bottom plate, the cylindrical body, and the second bottom plate are welded at the same time by stacking the two bottom plates and then heat-pressing with a scissors along the periphery of both bottom plates. Bag manufacturing method.   It has a discharge port in the lower part, and the discharge port has a short cylindrical shape with a collar part at one end, and the collar part is sandwiched between two synthetic resin holding members having a hole in the center, and provided in the interior bag body With the discharge port projecting from the hole, the inner bag body is formed by the weld portion continuously formed along the circumferential shape of the collar portion and the weld portion continuously formed along the outer periphery of both holding members. The interior bag used for the exterior container according to any one of claims 1 to 4, wherein the discharge port is joined together with both holding members.   The outer container according to claim 6, wherein a short cylindrical reinforcing member having a flange at one end is welded and fixed to the discharge port in a state of being inserted from the inner side of the inner bag body into the discharge tube. Interior bag used for   An outer container such as a container or a drum can in which the inner bag according to any one of claims 1, 2, 3, 4, 6 or 7 is accommodated.

Images