JPH02258559A - Production of plastic film bag easily opened and its opening method - Google Patents

Abstract

PURPOSE: To laterally expand pleats and to separate the mouth-forming edges of a bag corresponding to the expansion of the pleats so that a finger or a hand can be easily inserted into a bag mouth by forming the expandable pleats on one or both of front wall and rear wall, and drawing out the handles. CONSTITUTION: The pleats 32 are vertically formed on the walls 14, 16 of a bag over the entire vertical height of the bag. These pleats 32 include an intermediate panel 34 between the panel forming parts 36, 36 integrally therewith. The lower edges of the pleats 32, 32 of the walls 14, 16 are sealed on its lateral joint part. When the handles 24, 24 are side outwardly drawn out, the static adhesion of the parts particularly near the mouth portion 26 is conquered by the separating motion of the panel portions acting so that the panel portions of the pleats are relatively slided, the intermediate panel 34 is reversed, the outermost panel of the pleats is separated, and further the walls 14, 16 of the bag is separated from one another, and a gap sufficient for fully opening the bag by a hand can be formed between the upper edges of the walls.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a bag made of plastic film that inherently has a tendency to be difficult to open, and to a bag that can be easily opened, a method for manufacturing the bag, and a method for opening the bag.

[Background of the invention]

BACKGROUND OF THE INVENTION Plastic bags, ie bags made of thermoplastic synthetic resins, such as polyethylene films, are already widely used as bags for various products such as agricultural products, foodstuffs, and other general and specialty items. Such bags are produced in a variety of shapes and configurations, but
One of the most widely known is what is commonly referred to as a T-shirt bag.

This T-shirt (type) bag usually has a pair of gusset parts (gussets and/or reinforcement parts) formed on the sides, and a pair of gusset parts (gussets and/or reinforcement parts) formed on the sides and extending upward. It has a handle and a transverse mouth or opening therebetween. Other types of conventional handheld bags include bags having a handle in the center and bags having handle means formed by cutting and removing the front and rear walls of the bag. It is also possible to divide the bag into multiple compartments, as in commonly owned U.S. Pat. There are also simply flat bags without handles or gussets, such as those often found on product stands.

Plastic bags as described above have various significant advantages over traditional paper bags for various products, foodstuffs, etc., and have therefore gained wide acceptance in the market. However, a particular problem with the use of plastic bags is the difficulty of opening the bag. For example, the static adhesion that always exists between the extremely thin films of each bag.
ng). Furthermore, there is also a tendency for the films to stick together as a result of the migration of additives and other chemicals to the surface of the plastic film. The adhesion of the bag sheets together is also achieved by cutting operations to form the opening of the bag.
This is often caused, for example, by the formation of slight cold welds between the cut edges of the sheets.

In either case, the sheet or film at the bag opening cannot be insulated, but it eliminates the bag's natural tendency to remain closed;
It is inherently difficult to first be able to grasp or pinch the sheet or film sufficiently to effect the desired opening of the mouth. This is true whether the bags are removed from a pack, cut from a roll, or separated into individual bags.

[Object of the Invention, Summary of Structure, and Effects] The present invention particularly relates to plastic bags, that is, bags made of thermoplastic resin film, in which a means for facilitating opening of the bag opening is provided integrally with each bag. Regarding the bag provided as part.

More particularly, the invention proposes to produce a plastic bag with an expandable pleat formed on one or both of the front and rear walls. The position of the pleats in each bag is determined depending on the type and nature of the bag. The present invention also proposes and enables multiple ways to utilize pleats to open the bag. These methods vary from manipulating the folds directly to manipulating the edges of the bag away from the folds, and also include such manipulations, such as removing the bag from the bag. It also includes operations performed in conjunction with other operations such as placing the bag on a mounting table. Particularly in the case of T-shirt type bags, where the handle is usually pulled outward when the bag is taken out of the bag and/or engaged with the arms of the R stand, this may be necessary in conjunction with the other operations mentioned above. It is convenient to use the folds as an opening. As will be described in more detail below, when the handle is pulled outward, this causes the folds to expand laterally and the edges of the opening of the bag also undergo a corresponding isolating movement, preventing the fingers or hand from reaching the opening. This makes insertion easier.

To facilitate the opening of the bag opening, the front and rear seats or front and rear walls of the bag are essentially provided with thermal melting transversely to the bag opening formed by their free upper edges. There is a pleat (bleat) extending vertically over the entire height of the bag between the bottom of the bag formed by the closure and the integral lower edge. The pleats in the sheet or wall are formed by two opposing wall sections with an intermediate panel section between them, the two wall sections forming overlapping panels of equal width. This configuration allows the pleats to be used in different ways for opening the bag opening. For example, in the case of a T-shirt type bag, the two folds of the folds can be separated by pulling the handle outward, or in the case of a bag with no handle and a straight flat top, by pulling the upper opposing corners outward. The panel formations slide relative to each other and the intermediate panel portion rotates or pivots between them, thereby causing electrostatic or static cling.
It is possible to overcome the inherent tendency of sheets or films to become difficult to separate from each other due to chemical adhesion, cold welding, etc., and to isolate the panel sections from other walls of the van and to separate the corresponding walls or At least the opening portion can be moved in the lateral direction. By providing not only one layer of the bag but also the base wall with a panel portion similar to that described above that works together in a sliding and sliding manner, it is possible to further facilitate separation between walls or sheets at the bag opening. I can do it. This is because, with this configuration, the mutual release of the edges forming the bag opening is more assured, the initial separation between the sheets and the opening of the bag opening is facilitated, and the opening into the opening is facilitated. Approaches can be made without any hindrance.

It will be appreciated that it is necessary to open the bag further by hand in order to place the item inside the bag.

However, the above-described difficulties with respect to the initial separation of sheets or walls resulting from static adhesion or cold welding etc. are overcome. Moreover, such a construction does not require any additional materials compared to conventional bags, nor does it require any special manipulation or handling, just as is normally done with T-shirt style bags. Initial opening can be performed by simply pulling the upper corners of the bag slightly outward at both ends of the bag opening, as is commonly done when the bag is placed on a mounting table or the like.

In addition, the pleats on the wall are thicker at these points and form vertical free ends, so they can be pinched directly with two fingers and pulled forward. , which makes it possible to isolate the walls of the bag, first at the bag opening and then over the entire height of the bag. This opening method can be performed at the same time as bags are being pulled from a stack or roll thereof, thereby allowing the bag to be removed and opened at the same time. Advantageously, individual bags can be opened by directly pinching the pleats on the two walls of the bag.

Another method of using pleats to open a bag is to pinch or pinch the pleated front and rear sides of the bag opening with two fingers and slide the fingers over each other. This will cause the bulges of the pleats to slide over each other and unravel, allowing the edges of the opening to open wide enough to pinch those edges, and then open the opening. It becomes possible to open directly.

In the case of a carry bag or a bag with a flat or straight top edge, the pleats are usually located in the center of the bag and extend vertically downward from the opening to the sealed lower edge. This central arrangement of the pleats is advantageous because once the initial expansion has taken place in the center of the bag opening, it is possible to fully open the bag by pinching the upper edge of the bag with your fingers. This is because it becomes easier.

The use of pleats in the walls (film) of plastic film bags can be used, for example, in bags having multiple chambers or compartments of the type disclosed in the above-referenced U.S. Pat. No. 4,696,403. This is particularly advantageous in cases where In the above-mentioned US patent, the bag is divided into individual chambers that are laterally adjacent, and each chamber is configured to serve as an individual container. Typically, the compartments formed in standard width bags have relatively narrow openings, making it necessary to open them individually. This relatively narrow opening width makes opening the bag more difficult. The invention proposes to form pleats in one or both of the front and rear walls of each compartment. With this arrangement, depending on the method adopted for opening the folds, all the compartments can be opened simultaneously or they can be opened individually.

In the actual manufacturing process of making bags from usually continuous film tubes, there is only one additional step, and this is the creation of longitudinal pleats on the opposing front and/or rear walls of the bag. This means that at least one thread is formed.

The formation of the pleats is performed in a step prior to the heat sealing step and before forming the upper and lower edges of the bag and before forming the bag opening.

By forming the bag as described above, it is possible to reduce the width of the bag, which has the dual purpose of reducing the space and container dimensions required for storage and shipping of the bag product. The following effects can also be achieved. Furthermore, when the bag is roll-shaped, the core supporting the roll and the bag container for storing it can be made smaller, which is an economical effect. Since bags of the type that are relevant to this invention are manufactured in units of millions, economy in all aspects of manufacturing, shipping and bag use is an important factor for all products. However, there is a considerable amount of money involved.

Each panel of pleats formed in the wall (film or sheet) of the bag is only secured along the sealed bottom of the bag. Therefore, although the total width of the bag is reduced at the time of shipment, when the bag is opened,
The folds can be fully expanded to cover the entire height of the bag, except for the area immediately adjacent to the bag. Thus, despite the pleats, the full effective width of the bag can be utilized during use. Furthermore, since the pleats remain fixed on the lower edge of the bag when opened, the portion of the pleats that are directly external to this lower edge creates a flat bottom, thereby creating a flat bottom. The convenience of stuffing products, etc. into the bag is planned.

It will be understood from the details of the present invention described in detail below that the present invention has other objects, structural features, and effects other than those described above.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the accompanying drawings, FIG. 1 shows a basic handbag or T-shirt bag 10, and FIG. A flat or straight bag 12 with a flat top edge is shown.As shown, these bald areas 10 and 12 are formed by a synthetic resin film (
It is formed from a predetermined length of a cylindrical body (or a sheet), and this cylindrical body is crushed into a flat plate to form the front wall or seam 4 (on the near side in the drawing) and the seam 4 (on the opposite side in the screen).
A rear wall or sheet 16 is formed. These walls1.
The opposing lateral edges of 4.16 are integral with each other directly in the bag 12 and through an inwardly formed side gusset 18 in the bag 10. Although any bag may be formed without the gusset 18, its provision has been found to be a particularly preferred arrangement for obtaining the greatest possible width and volume in the bag. T
In the case of a shirt-type bag, the gusset portion 18 also serves the function of reinforcing the handle. Therefore, the gusset portion 18 corresponds to a gore and/or a reinforcing portion.

The upper edge 20 and lower edge 22 of the T-shirt type bag 10 in the transverse direction are processed by heat-sealing or the like to the front wall 14 and the rear wall 16 so as to sandwich the upper and lower edges of the gusset part 18. Closed by. A bag mouth or opening 26 extending transversely between the oppositely formed handles 24, 24 and their inner ends is essentially a U-shaped cut inwardly from the top edge of the bag. (cut out)
It is formed by doing the following. If desired, the opening 26
The connection or transition between each end of the handle 24 and the handle 24 can be shaped to avoid stress concentration.

In the case of the flat top bag 12 shown in FIG.
4 and the entire length of the upper edge of the rear wall 16 form a bag opening 26. The lower edges of these walls 14,16 are sealed in a known manner, for example by heat sealing.

The bags 10 and 12 described above are known and are used on a large scale commercially. However, as discussed above, a major problem with such bags is that it is difficult to open the opening and gain access to the interior. This problem occurs due to various factors, but
These include static adhesion and the tendency of the opening edges to stick together as a result of the cutting operation. It should be noted here that in the accompanying drawings, the thickness of the wall or sheet of the bag is considerably exaggerated by two lines for the sake of illustration. It should be understood that the actual thickness of the sheet or film is less than the single line drawn in the illustration.

The present invention provides a means to facilitate the initial opening of the opening 26 by separating or isolating the top edges 28 and 30 of the front wall 14 and the rear wall 16, which form the opening 26, from each other. It is particularly oriented. Essentially, this means consists of two panel sections formed in the vertical direction of one or both of the bag walls 14 and 16 in an integral series and overlapping manner, with these panel sections being formed transversely with respect to each other. It is configured to be slidable and such that as a result of this mutual movement, the portions of the opening in the wall of the bag are laterally separated from one another.

More specifically, each of the bag walls 14 and 16 is formed with a vertical burrito 32. The pleats 32 are formed vertically downward from the top edges 28 or 30, preferably throughout the vertical height of the bag for various reasons, including manufacturing considerations. Also,
This pleat 32 includes an intermediate panel portion 34 between and integral with two equal width portions of the wall 14 (or 16), namely panel formations 36, 36 (FIG. 2). The panel formation 36.36 is also the flat portion of the two parts of the wall 14 (or 16) on either side of the centrally located pleat.
Form the panel part of the pleats. Folds 32 in walls 14 and 16
．． The lower end of 32 is sealed at a transverse seam or lower edge or sealed bottom.

The directions in which the folds 32 formed on the front wall 14 and the folds 32 formed on the rear wall work 6 are opposite to each other as shown in FIGS. 1 and 5, or as shown in FIG. 4. The outer bends 38, 38 of the pleats can be placed on either side of their common vertical center line or on the same side thereof. It will be appreciated that the inward bends of the pleats are located inwardly of the inward bends of the lateral gussets 18. Furthermore, folds 3
Although the width of the gusset portions 18.2 is illustrated as being only slightly less than the transverse distance between the gusset portions 18.18, its actual width should be such that sufficient sliding relative movement exists to effect the desired separation of the walls of the bag. -layers can be made as narrow as possible.

FIG. 15 schematically illustrates a method for manufacturing a basic bag according to the present invention. The method includes manufacturing a continuous cylindrical body A of plastic film material. This cylindrical body A is formed with at least one longitudinally continuous pleat B, which consists of inner and outer panel parts or panel forming parts that overlap with each other with an intermediate panel part in between. is integral with the inner and outer panel sections, but apart from this continuity there is substantially no interconnection or joint between the panel sections.

The pleated cylindrical body is crushed to form a front wall and a rear wall C9C that are integral with each other at both side edges, and the pleats B are formed on one or both of these front and rear walls. Formed in substantially the same plane as the plane.

Forming transverse seals in the front and rear walls at longitudinally spaced locations of the tubular body, thereby allowing the front and rear walls to form longitudinally spaced , forming a series of individual bags E each having a sealed bottom formed by a transverse seal.

With respect to the basic T-shirt type bag 10 shown in FIG. 1, the automatic opening of the opening 26 thereof is performed in the normal manner associated with placing the bag on the platform, as shown in FIG. This can be achieved by grasping the handles 24 and 24 and pulling them outward. Handle24.
The laterally outward pulling or movement of 24 as described above causes relative sliding movement of the panel portions of the pleats, causing the intermediate panel portions 34 to reverse or invert and isolate the outermost panel portions of the pleats. , and more importantly acts to isolate the walls 14 and 16 of the bag from each other. Such isolating movement of the panel parts overcomes static adhesion or similar sticking between the walls 14 and 16, especially their parts near the opening 26, and provides sufficient space for the bag to be fully opened by hand. A gap can be created between the upper edges of the walls.

As is apparent from FIG. 11, the opening of the pleated flat-top bag 12 is located outside the central vertical pleat 32 in the wall of the bag, as in the case of the T-shirt bag 10. This can be done by pinching the upper portions and pulling those portions outward to unwind or open the pleats 32 formed in either or both of the front and rear walls.

If the pleats 32 are not provided, the transverse movement of the handles 24, 24 of the bag 10 or the upper corners of the bag 12 as described above will only result in a longitudinal movement of the edges of the opening. There is no tendency for mutual separation of the walls or for the effect of openings. When the opening pleats are provided, sufficient forces are developed across the edges of the opening to cause them to separate laterally.

Bag 10 or 1 by putting products etc. in the bag
2 can be left completely open,
At this time, the pleats 32.32 and, if provided, the gusset portions 18.18 can also be fully expanded over substantially the entire height of the bag, excluding the area of the sealed bottom. . At the bottom of the bag, the lateral gussets 18.18 fold into a triangular shape, thus making it possible to form a flat bottom. The central pleats 32, 32 are folded in the bottom seal or in the immediate vicinity of the lower edge 22, again further enhancing the formation of a generally flat bottom, a particularly desirable requirement for the storage of goods, etc. Make it easy.

Figure 6 shows bag 4 bent over the other side of the bag with a flat top edge.
0, in this bag, holes for forming handles, i.e., handle holes 42, are punched and formed in the front and rear walls at a distance from the free top edge of the upper edge forming the opening. has been done.

The wall portion 44 between this hole and the top edge becomes the handle. In addition, in the bag 40 of this example, the already described folds 3
2, an opening vertical pleat 46 is provided along the entire height of the bag 40 between the free top edge and the closed lower edge and vertically. . Forming a flap 46 is particularly preferred for bags such as bag 40. This is the handle hole 42
This is because the formation of the bag necessarily tends to increase the degree of mutual adhesion at the site of the opening of the overlapping walls, making normal opening of the bag more difficult. The initial opening of the bag 40 can be performed by the method shown in FIG.

Referring now to FIG. 7, the bag 5 illustrated therein
0 is basically a two-compartment T-shirt type bag, in which a vertical joining line 52 in the center forms two compartments or compartments 54, 54, each connected to a handle 56, and The bag 50 is divided into two containers. The construction of this bag is similar to that of the previously referenced U.S. Pat. No. 4,696.
．． As disclosed in detail in No. 403.

Opening these openings 58,58 is particularly difficult due to the limited width of the compartments 54,54 and the formation of the openings 58 of each chamber between the handles 56,56. . Accordingly, one of the important objects of the present invention is to provide a method that facilitates the opening of the openings 58 in each compartment of the bag 50.

The bag 50 has a front wall and a rear wall, which form two compartment front and rear walls, respectively. Each layer of the bag has a pair of opening pleats 60.60 extending the entire vertical height of the bag, these pleats being located in the center of each of the two compartments 54.54. Each strip is provided downward from the opening of the partition. Each pleat 60 generally corresponds to the already mentioned pleat 3.
2 and 36, with an intermediate panel portion formed between equally wide portions of the walls of the compartment, i.e., panel formations. With this configuration, the two partition chambers 54,54 can be opened at the same time by grasping the oppositely formed handles 56,56 and pulling them outward, as shown in FIG. Instead of this method of using the pleats, especially when the bag 50 is divided to form multiple containers, the use of the pleats for the initial opening of the bag is shown in FIG. As shown, it is possible to directly pinch the area of the fold where the thickness has increased to perform initial isolation in the lateral or anteroposterior direction of the upper edges of the partition. As shown in the figure, it is preferable to simultaneously pinch the folds of the two overlapping walls and pull them apart.

Still another method is to hold the folded portions of the front and rear walls of the partition between two fingers and shift them in the longitudinal direction.

As a result, the panel part of the pleats can be deformed to wrap around the opening of the partition and can be isolated to the outside.
You can then put your finger into the opening and fully open the bag. This method is illustrated in FIG. 14, taking the case of a single-chamber bag as shown in FIG. 5 as an example.

The initial opening method shown in FIGS. 13 and 14 is T
It will be clear that it is equally applicable to all bags disclosed herein, formed with single or multiple chambers, including shirt-shaped bags and flat-topped bags.

As mentioned above, regardless of the particular type of bag, it is possible to provide pleats on only one of the front and back walls of the bag, as shown by the T-shirt style bag in FIG.
It is possible to form pleated bags. Such bags are particularly constructed to be supported by the arms of the member supporting the bags so that they can be filled one after the other. By providing pleats on the front wall of the bag, the user can spread out the pleats by pinching the pleats at the opening of the bag and pulling them toward the user. You can prepare for stuffing by separating the area from the wall and pulling the bag towards you. Similarly, regarding the multi-chamber bag shown in FIGS. 7 and 10, an example in which vertical folds are provided on both the front wall and the rear wall of the compartment has been described, but one side of each compartment It is also possible to easily implement a structure in which only one wall is provided with pleats and the other wall is not provided with pleats.

FIG. 8 shows a plastic film bag 62, also in accordance with the present invention, but inside the bag there is a front wall 68.
A plurality of chambers or partition chambers 64 are formed by internal partitions 66 formed by fixing the rear wall 70 and the rear wall 70 to each other by heat fusion. In the illustrated example, a total of two partitions are formed, one on each side of the central handle 72 that protrudes in the vertical direction, but it is possible to form two or more partitions. In that case, it is preferable to form chambers equally balanced on both sides of the central handle 72 so as not to cause any inconvenience in carrying the bag.

Each partition 64 opens upward through an opening of the partition formed along the outer upper edge of the handle 72 and between the overlapping front wall 68 and rear wall 70. According to the invention, each compartment 64 has front and rear compartment walls that are part of the front and rear walls of the bag. These partition walls have opening pleats 74.7
4, which are formed as described above and extend downwardly from the compartment opening, preferably over the entire height of the compartment. With this configuration, it is possible to open all the compartments simultaneously by the method shown in FIG. 10 or by the method shown in FIG. 11. Instead of these methods, it is also possible to open each partition by the methods shown in FIGS. 13 and 14.

The use of pleats for initial opening is particularly important in bags with multi-chamber or compartmental configurations such as those shown in Figures 7 and 8; This is because as the effective width of the plastic film bag decreases, the inherent difficulty in opening the plastic film bag increases greatly. Thus, multi-chambered or compartmentalized film bags are both practical and highly preferred for a variety of reasons, including those detailed in the above-referenced U.S. Pat. No. 4,696,403. However, the current situation is that various problems have arisen in their use, particularly with respect to access to the partitioned room.

Therefore, by providing a basic bag with the pleats according to the invention, the use of such a bag can be made easy, efficient and practical from all points of view. I can do it.

FIG. 9 schematically illustrates a method for manufacturing bags in the form of a continuous strip suitable for back packaging in roll form, adapted from the embodiments disclosed herein. Bags from this roll are used one after the other by separating the first bag from the next bag in a known manner. Depending on the type of bag and the manner in which the bag is grasped for separation from the roll, the unfolding of the pleats can occur at the same time as the bag is being separated or afterward. With reference to FIG. 12, it will be appreciated that it is also possible to provide the bags in a stacked manner.

It is believed that the above description provides a detailed explanation of the present invention. Other embodiments and modifications that may occur to those skilled in the art are considered to be within the scope of the invention.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a plastic film upper shirt-type bag with a pair of expandable pleats in overlapping walls. FIG. 2 is an enlarged cross-sectional view of the bag taken substantially along the plane I-1 of FIG. 1 showing the pleats formed in the front and rear walls; FIG. 3 is a perspective view of the upper portion of the bag of FIG. 1, with the opening opened by pulling the opposing handles outward; FIG. 4 is a perspective view similar to FIG. 3 showing a modified example of pleat formation. FIG. 5 is a perspective view of a pleated flat top bag or a bag lacking a protruding handle. FIG. 6 is a perspective view showing a modified example of a bag with a flat top edge in which carrying holes are formed in the front and rear walls. FIG. 7 is a perspective view of a bag having central vertical dividing lines or joining lines forming respective pleated compartments. FIG. 8 is a perspective view showing a bag having a handle and an internal partition in the center and pleats on both sides of the partition. FIG. 9 is a schematic perspective view of a rolled product of a pleated bag according to the invention. FIG. 10 is a partial perspective view showing a method of opening the compartment-forming bag of FIG. 7. FIG. 11 is a partial perspective view showing how to open a flat top bag. FIG. 12 is a partial perspective view showing a method of pulling out and opening bags one after another from a group of bags hung on an arm of a mounting table by directly pinching the front wall of the bag. FIG. 13 is a partial perspective view showing a method of opening the bag or its compartment by directly pulling apart the opposing pleats with fingers. FIG. 14 is a partial perspective view showing an opening method in which the pleat forming portions of the front wall and the rear wall are shifted parallel to each other to cause the pleats to expand. FIG. 15 is a schematic diagram illustrating a manufacturing method for manufacturing a pleated bag according to the present invention. 1.0.12,40,50.62...(plastic film) bag (10...handbag or T-shirt type bag, 12...flat top edge bag), 14...front wall (sheet or film), 16... Rear wall (sheet or film), 18... (side) gusset part, 20.
... Upper edge, 21... (sealed) lower edge (or sealed bottom), 24,56.72... Handle (means), 2
6.58... (bag) opening, 32.46, 60.
74... Opening initiation means or pleats (bleats or pleats), 34. ．． 36... Panel part (34... Intermediate panel part, 36... Panel forming part), 42... Handle hole, 52... Joining line (partition means), 54.64
...room or partition, 66... (internal) partition (partition means). FIG, 6 FIG, 7゜FIG, 13゜FIG, I5゜

Claims (1)

[Scope of Claims] 1. A bag consisting of a front wall and a rear wall that are integral and overlap at both side edges, the front wall and the rear wall having an opening in the transverse direction of the bag and having opposite ends. having overlappingly engaged upper edges forming a sealing bottom and sealing lower edges forming a sealing bottom such that outward movement of the opposing ends of the opening with respect to each other causes a corresponding displacement of the front and rear walls. An easy-to-open plastic film bag that is provided with an opening initiation means integral with the bag, which separates the upper edge in the front-rear direction and initiates opening of the opening. 2. It has a handle that is integral with the front and rear walls and extends above the opening at the opposite end of the opening, and when these handles are moved outward with respect to each other, 2. The easy-to-open bag of claim 1, wherein the opposite end of the responsive opening is configured to move outwardly, and the opening initiation means is spaced inwardly from and formed between the carrying handle. A bag made of plastic film. 3. The opening initiation means comprises pleats formed downwardly from the opening toward the lower sealing edge and in the front and rear walls, each pleat consisting of overlapping panel sections that are substantially independent with respect to each other; are slidable relative to each other when the opposing ends of the opening are moved outwardly, and each pleat panel portion has an intermediate panel portion that allows the opposing ends of the opening to be moved outwardly. 3. The easily openable plastic film according to claim 2, wherein the intermediate panel portion is inverted when the plastic film is opened, thereby facilitating separation of the other panel portions of the pleats in the front-back direction and the corresponding separation of the front and rear walls. made bag. 4. Each pleat is formed to span the entire height of the corresponding front and/or rear wall, and the lower end of the panel portion of the pleat is sealed at the sealed lower edge of the front and rear walls to form the lower end of the panel. Claim 3, wherein the pleats are configured such that the pleats can be completely opened at a portion spaced upward from the lower end of the panel.
Easy-to-open plastic film bag as described. 5. The easy-to-open plastic film bag according to claim 4, which has gusset parts integral with both side edges of the front and rear walls. 6. The easy-to-open plastic film bag according to claim 5, wherein a single pleat is formed at the center of each of the front and rear walls. 7. The opening initiation means comprises at least one pleat formed downwardly from the opening toward the lower sealing edge and in either the front or rear walls, each pleat being a substantially independent overlapping panel with respect to each other; the panel portions are slidable relative to each other when the opposing ends of the aperture are moved outwardly, and each pleat panel portion has an intermediate panel portion that extends outwardly from the opening. Claim 1, wherein the intermediate panel section is inverted when the opposing end section is moved outward, thereby facilitating separation of the other panel sections of the pleat in the front-back direction and the corresponding separation of the front and rear walls. Easy-to-open plastic film bag as described. 8. The easy-to-open plastic film bag according to claim 7, wherein holes are formed in the front and rear walls at intervals in the vertical direction from the upper edge to provide a handle means. 9. Consisting of a front wall and a rear wall, these walls having a closed lower edge and a handle integral with these walls extending laterally and upwardly, with a transverse opening between the lower ends of the handles. The bag is made of a thermoplastic film material having an opening integral with the bag, which automatically opens the opening in response to the movement of the handles laterally and outwardly with respect to each other. A T-shirt type bag with means. 10. The opening initiation means comprises pleats formed downwardly from the opening toward the lower sealing edge and in the front and rear walls, each pleat consisting of overlapping panel sections that are substantially independent with respect to each other; are slidable relative to each other when the opposing ends of the opening are moved outwardly;
and each pleat panel portion has an intermediate panel portion;
When the opposite end of the opening is moved outward, this intermediate panel section is inverted, making it easy to separate the other panel sections of the pleats in the front-back direction and the corresponding front and rear walls. The T-shirt type bag according to claim 9. 11. Each pleat is formed over the entire height of the corresponding front wall and/or rear wall, and the lower end of the panel portion of the pleat is sealed at the sealing lower edge of the front and rear walls, The edge and the area immediately adjacent to the edge form a panel lower end that has an overlapping configuration to avoid separation of the panel parts,
11. The T-shirt type bag according to claim 10, wherein the pleats have no fixed portion at a portion spaced upwardly from the lower end of the panel and are configured to be completely openable. 12. The T-shirt type bag according to claim 11, further comprising a gusset portion integral with both side edges of the front and rear walls. 13. A bag comprising overlapping front and rear walls that are integral at opposite edges, the front and rear walls forming an opening in the top transversely of the bag, the upper side of the bag being in overlapping engagement. an edge, a sealed lower edge forming a sealed bottom, and partition means forming transversely adjacent compartments within the bag, each compartment having a predetermined width and overlapping front and rear walls of the bag; an upper compartment opening formed by a portion of an overlappingly engaged upper edge of the bag having a front compartment wall and a rear compartment wall comprising portions and engaging the compartment wall; vertical pleats for the opening are formed in at least one of the front and rear walls of each compartment, each pleat extending from the compartment opening to the sealed bottom of the bag. , an easy-to-open plastic film bag consisting of stacked panels that can be expanded in the transverse direction. 14. The panel portions of the stacked configuration of each pleat are slidable transversely relative to each other when the front and/or rear walls of the compartment are moved outwardly to the sides of the pleat, thereby opening the opening of each compartment. The upper edges forming the compartments can be separated in the front-rear direction, and each pleat panel has an intermediate panel section, and the front and/or rear walls of the compartment are separated from each other in the front-rear direction. A claim in which the intermediate panel is inverted when it is moved laterally outward, facilitating isolation of the other panel portions of the pleats in the front-back direction and the corresponding isolation of the front and rear walls of the partition chamber. 14. The easy-open plastic film bag according to 13. 15. Each pleat is formed over the entire height of the front and/or rear wall of the corresponding compartment, and the lower edge of the panel portion of the pleat is sealed at the sealing lower edge portion of the front and rear walls of the bag. 15. The easy-open plastic film bag of claim 14, wherein the pleats form a lower edge of the panel and are constructed such that the pleats can be fully opened at a location spaced upwardly from the lower edge of the panel. 16. Handles integral with the front and rear walls of the bag, extending outward from the front and rear walls of the partition chamber and above the opening at the top of the bag, facing both sides of the partitioning means, and these handles are outside of each other. 16. The easy-to-open plastic film bag according to claim 15, which is a handheld bag configured so that when the bag is moved in one direction, the opening of each compartment can be expanded accordingly. 17. Claim 17, wherein a separation line is provided in the longitudinal direction of the partitioning means for selectively separating the bags between the partitions, thereby forming individual containers each having a partition. 16. The bag made of plastic film that is easy to open. 18. The easy-to-open plastic film bag according to claim 17, wherein each of the front and rear walls of each partition is provided with pleats at the center thereof. 19. Claim 19, wherein a dividing line is provided in the longitudinal direction of the partition means for selectively dividing the bag between the partition chambers, thereby forming individual containers each having a partition chamber. 15. The easy-open plastic film bag according to 15. 20. A handle is provided at the center of the upper edges of the front and rear walls of the bag integrally with those walls, and the handle projects upward from the upper edges to form a central carrying means for the bag. 16. The easy-to-open plastic film bag according to claim 15, further comprising: a partition means provided below the handle in a vertical direction so as to coincide with the handle so as to form partition chambers on both sides of the handle. 21. Widely used by consumers to contain various products, foodstuffs, etc., so that consumers can easily overcome the inherent tendency of bags to be difficult to open, and thus make it easier to open the bag. A plastic film bag of the type described above, having a flat front wall and a rear wall made of plastic film material, the walls overlapping and joining together at side edges forming both side edges of the bag. front and rear walls, with a closed bottom of the bag formed by a straight heat-sealed lower edge of those walls and an opening of the bag formed by a substantially unjoined upper edge of those walls; at least one fold is formed on at least one side of the
The pleats extend continuously from the opening of the bag to the closed bottom and consist of sections of the front and/or rear walls that are folded to form overlapping inner and outer panel sections; but have substantially no other interconnected portions other than their overlapping portions and lie substantially in the same plane as the walls on which they are formed and the walls are formed with pleats. By rotating the pleats from the plane, it is possible to separate the inner and outer panel portions of the pleats in the front-rear direction or the outer-interior direction, and correspondingly isolate the portions of the front and rear walls of the bag adjacent to the panel portions. An easy-to-open plastic film bag having a structure that overcomes the inherent tendency of bags to be difficult to open and thus makes it easy to open the bag. 22. Widely used by consumers to contain various products, foodstuffs, etc., so that consumers can easily overcome the inherent tendency of bags to be difficult to open, and thus make it easier to open the bag. A method for manufacturing a plastic film bag of a type in which measures have been taken to ensure that the bag is made of plastic film, the process comprising: forming a continuous cylindrical body of plastic film material; at least one longitudinally continuous section of the tubular body folded to form a panel section that is continuous with the intermediate panel section and that apart from the intermediate section is folded to form a panel section that is substantially free of other interconnections. A step of forming the pleats of the strips into a cylindrical body, forming an integral overlapping flat front wall and a rear wall at both side edges, and disposing the above-mentioned at least one pleat on one of the front wall and the rear wall to form a substantially flat front wall and a rear wall. a step of forming a cylindrical body in the same plane as the cylindrical body, a step of forming a sealing portion in the transverse direction of the front wall and a rear wall at portions spaced apart in the longitudinal direction of the cylindrical body, and a step of forming the sealing portion in the transverse direction of the front wall and the rear wall. the opening comprising the step of at least substantially separating the front wall and the rear wall at longitudinally spaced locations so as to form a series of individual bags with each bag forming a sealed bottom of each bag; Easy method for manufacturing plastic film bags. 23. A method for opening a plastic film bag formed by overlapping front and rear walls having overlapping upper edges forming an opening, and having a sealed lower edge and sealed side edges, the method comprising: providing a pleat extending vertically downward from the opening of the bag on at least one of the wall and the rear wall; touching the pleat forming part of the front wall and the rear wall with a finger;
pinching them together, then sliding the fingers in opposite directions to slide the front and back walls near the opening and laterally unfold the upper edges forming the opening. A method for opening a plastic film bag comprising separating the two and allowing the fingers to be engaged between them. 24. A method for opening a plastic film bag formed by overlapping front and rear walls having overlapping upper edges forming an opening, and having a sealed lower edge and sealed side edges, the front Provide folds extending vertically downward from the opening of the bag on each of the walls and the rear wall, pinch the forming parts of the front and rear folds with both hands near the upper edge, and push these pinched parts outward. A method for opening a bag made of plastic film, comprising moving and unfolding the upper edges forming an opening, laterally separating them so that fingers can be engaged between them.