EP2141082A1

EP2141082A1 - Bag for waste with closing string device and closing method and production method of the bag

Info

Publication number: EP2141082A1
Application number: EP09005914A
Authority: EP
Inventors: Virago Mr. Graziano
Original assignee: Virosac SRL
Current assignee: Virosac SRL
Priority date: 2008-07-02
Filing date: 2009-04-29
Publication date: 2010-01-06
Also published as: IT1391624B1; ITTV20080090A1

Abstract

Bag, particularly a waste bag, with a closing string device and a closing method of the opening of the bag and a production method of the bag, which, in correspondence with the opening border, is provided with a string (200) made of the same material with which the bag is obtained, said string being placed inside or outside one of the two edges defining the opening, with the ends welded at the sides of the bag; the string being wound with a neck around the curled opening, and then laid under the rest portion of the string. Continuous bags production method, in which the biodegradable thermoplastic or plastic material folded film is unwound from the single-folded material coil, along which the string (200) is continuously joined, outside the film or internally between the two edges of the folded film; said string being successively welded to the folded film at the two ends, wherein each welding is carried out at the dividing line between one bag and the contiguous one.

Description

This invention relates to a bag, in plastic materials or thermoplastic material e.g. PE/MD, biodegradable PE/LD as the Mater-Bi^®, particularly useful for containing waste, provided with a string device useful for closing and fixing, even temporarily, the opening of the bag; this invention relates to the method for closing the opening of the bag, as well as to the production method of the bag itself.

Field of the invention

The invention finds particular if not even exclusive application in the field of accessories for bulk material containers, e.g. waste bins, particularly bags of the type made in plastic film, particularly intended to containing organic and dry waste and, in any case, waste in general.
Among the accessories commonly used in the domestic field, the bags intended to contain waste are essentially useful. In most general cases, they are made of a plastic material. The production material, depending on the specific consistence and composition of the waste to be contained, can also be of a biodegradable type. By and large, such bags are manufactured by extruding and heat sealing a plastic film, whose thickness and dimensions can vary according to the particular intended use. Thus, somewhat diffusingly, one can find on the market small sized bags for domestic single-family use and larger and higher consistency bags with a greater capacity particularly intended to contain the waste of apartment buildings besides being particularly useful for the use in the field of a community.
Concerning the production of waste sacks and bags, especially in recent years, an effort has been made dedicated to the research of innovative solutions which had to be, on the one hand, able to make their use easier, and on the other hand to bring about a differentiation of the product so as to allow a possible influence on the choices of a potential consumer. Some innovations moved in the direction of producing a material composition so as to produce the bag by means of the use of biodegradable substances, in other cases still, some solutions have been addressed in the identifying appropriate systems able to allow the easing of the operations concerning the closure of the opening of the bag itself.

Prior art

The object of this invention is therefore directed towards the research of an optimal solution to allow the effective closure of the opening of a bag as well as the production of the bag itself provided with closing means of the opening. Research about anteriority has been carried out in patent literature, which evidenced some not particularly relevant anteriority.
For example, in 1970, GB1333578 (Industriele) already described a plastic bag provided with a string or tie for the closure of the plastic bag which is joined to the plastic bag, in order to avoid separate strings or the loss of the closing string. The invention refers to a combination of a number of plastic bags and a elongated series of integral closing strings made of plastic material, with at least one string for each plastic bag, where the string or tape or ties.
GB1237894 (Papro) describes a waste bag, which is provided with a tape or a rope, joined to the bag by means of a coating sheet.
WO90/08071 (Heiremans et al. ) describes a method and a device to produce a waste bag and a tape to close said bag, wherein the bag is initially obtained by a synthetic material film, with a perforation obtained in said bag and a tape to be pulled which is the closure device. The closing tape is obtained by means of perforation of the synthetic material film, along two parallel lines at a distance between 1 and 3 cm. The synthetic material film used to produce said bags to be wound in coils in a continuous way is of the type obtained by means of extrusion in a cylindrical configuration, in order to be, successively to the extrusion phase, locally welded in such a way as to obtain single bags, joined on the bottom.
JP9208002 (Suzuki ) describes a waste bag to be wound in coils, which is provided with an easily closing tape which is obtained from the same material from which the bag is obtained. The tape is obtained along the border of the opening, folding an edge on itself previously marking a portion of it. Concerning the bag, it is obtained by welding the two side ends of the plastic material film step by step, in such a way as to obtain bags adjacent to one another.
JP8318956 (Takatsu et al. ) proposes a plastic material bag which has an opening closing tape obtained as an integral part of the plastic bag. One bag is joined to the other along the side of the opening.
In conclusion one can reasonably consider as known:

a bag made of a biodegradable thermoplastic material or plastic material with an opening closable by means of a string possibly made of the same material from which the plastic material bag is obtained;
a bag made of a biodegradable thermoplastic material or plastic material in which the closing string is placed and joined along the opening of the bag on the outside of the bag itself;
a bag made of a biodegradable thermoplastic material or plastic material in which the closing string is placed along a channel obtained folding the border in correspondence with the opening of the bag;
a plastic material bag continuously obtained by means of the extrusion of a plastic material film and the subsequent following heat-sealing, wherein the bags are heat-sealed in correspondence with the opening or along the sides.

Drawbacks

In conclusion, we have observed that most of the above described solutions have drawbacks or, in any case, some limitations.
In principle the known string closing systems, in the case in which the tape is integrated or, in any case, provided with the bag, would not allow, due to the arrangement of said tape, an effective closure of the bag, with the result that often, because of the carrying out of a conventional tying as well, an accidental opening can occur. In any case the adopted closing systems do not protect the content, due to the fact that the achievement of an almost hermetic closure of the bag looks not very practicable. The matter is therefore complex because, once the bag containing the waste has been disposed of, a dispersion of the content in the environment usually occurs, causing a lot of problems from the point of view of the hygiene.
From these introductory considerations, one can perceive that the need to find alternative and more effective solutions is definitely relevant.

Summary of the invention

This and other aims are achieved by the present invention according to the characteristics of the included claims, solving the abovementioned problems by means of a bag, particularly a waste bag, with a closing string device and a closing method of the opening of the bag and a production method of the bag, which, in correspondence with the opening border, is provided with a string made of the same material with which the bag is obtained, said string being placed inside or outside one of the two edges defining the opening, with the ends welded at the sides of the bag; the string being wound with a neck around the curled opening, and then laid under the rest portion of the string. Continuous bags production method, in which the biodegradable thermoplastic or plastic material folded film is unwound from the single-folded material coil, along which the string is continuously joined, outside the film or internally between the two edges of the folded film; said string being successively welded to the folded film at the two ends, wherein each welding is carried out at the dividing line between one bag and the contiguous one.

Aims

In this way, through its appreciable creative contribution, the effect of which constitutes immediate technical progress, various advantages are achieved.
A first consisting in producing a plastic material bag, particularly for waste which, due to the fact that it is equipped with a string which is welded to the bag at the two ends, inside or outside and near the opening border, is able to allow a most effective closure of the opening. The implementation of the string around the curled opening allows the effective closing of the opening of the bag, preventing the dispersion of the waste and ensuring better hygiene.
A second aim consisting in that, due to the positioning of the string, the string tying becomes easier and intuitive, this operation being able to even be rapidly performed by a person who is not particularly skilled.
An additional aim was also the fact of allowing the production of a bag with an integrated closing string at a low cost. In particular, the fact that the string is welded to the bag must be considered as well, the string not being allowed to slip off for any reason.
These and other advantages, will be evident from the following detailed description of preferred embodiments, with the aid of the included drawings.

Content of the drawings

Figure 1 represents a front view of the bag of the present invention with the closing string placed along the external side and near the opening of the bag;
Figure 2 represents a front view of the bag of the present invention with the closing string placed along the internal side and near the opening of the bag;
Figure 3 is a perspective view of the single-folded film continuously unwound from an upstream coil, the film being the one to which the string is joined;
Figure 4 is a view of the sequence concerning the execution method of the tying;
Figure 5 is a partial view of the bag closed with the string.

Practical embodiment of the object of the invention

With reference also to the figures, one can observe that a bag (1a, 1b) particularly for waste in one of the cases can be made in such a way that a single-folded film (100) made of a biodegradable thermoplastic or plastic material, unwound from an upstream tubular coil which is cut in halves, has been previously obtained by longitudinally folding the film in half obtaining two specular edges (102, 103) facing each other, wherein the folding side corresponds to the base side (101) of the single-folded film (100) (figure 3). A station for the supplying of the string (200) is present downstream with respect to the unwinding station of the single-folded film (100), the string (200) being made of the same material of the single-folded film (100). The string (200) supplying station sets down the string (200), with a double or a single edge, near one of the overlapped edges (102, 103) at the side defining the opening (104).
In more detail figure 3 illustrates the case in which the string (200) overlaps the edge (103) and longitudinally with respect to the film (100) in such a way as to result in being parallel and close to the opening (104) side. In this way, a following welding station carries out at least one welding (30), orthogonal with respect to the advancing direction of the film (100) with a contextual execution of an intermediate preliminary-cut (40) in correspondence with the overlapped edges (102, 103) defining the dividing line between one bag and the following bag (1a) (Fig. 1). The bag (1a) (Fig. 1) appears with the string (200) placed on the outside against one of the two edges (102, 103), a little bit below and parallel with respect to the opening (104), with the two ends (201, 202) welded in correspondence with the sides along the corresponding welding portion (30).
In a second preferred solution, the string (200) is inserted between the two overlapped edges (102, 103), and longitudinally with respect to the film (100) in such a way as to always result in being parallel and close to the opening's (104) side. Successively performing at least one welding (30) with the contextual execution of an intermediate preliminary-cut (40), the dividing line between one bag and the following bag (1b) is obtained (Fig. 2). In this case, the bag (1b) (Fig. 2) appears with the string (200) placed inside it, a little bit below and parallel with respect to the opening (104), with the two ends (201, 202) welded in correspondence with the sides along the corresponding welding portion (30).
In order to obtain the tying (Fig. 4), the bag (1a, 1b) is curled in correspondence with the opening (104), making the string (200) hang with the head (210) on one of the sides of the bag (1a, 1b). The head (210) is therefore wound around the curled portion of the opening (104) forming at least one neck (211) to be laid under the rest portion (212) and pulled as much as needed to obtain a safe closure, by means of a bottleneck of the opening (104). The operation can also be repeated a second and third time for improved safety.

Reference

(1a, 1b) bag
(100) single-folded film
(102, 103) specular edges
(101) base side
(200) string
(104) opening
(30) welding
(40) intermediate preliminary-cut
(201, 202) end of the string
(210) head
(211) neck
(212) rest portion

Claims

Waste bag with closing a string device and the closing method of the bag and the production method of the bag, characterized in that it has a string (200) in correspondence with the opening (104) made of the same material with which the bag is obtained (1a, 1b), said string (200) being welded with the ends (201, 202) in correspondence with the sides along the corresponding welding portion (30).
Waste bag (1a) with closing string device and closing method of the bag and production method of the bag, according to claim 1, characterized in that the bag (1a) has the string (200) placed on the inside, a little bit below and parallel with respect to the opening (104), with the two ends (201, 202) welded in correspondence with the sides along the corresponding welding portion (30).
Waste bag (1a) with closing string device and closing method of the bag and production method of the bag, according to claim 1, characterized in that it has the string (200) placed on the outside against one of the two edges (102, 103) a little below and parallel with respect to the opening (104), with the two ends (201, 202) welded in correspondence with the sides along the corresponding welding portion (30).
Production method of the bag (1a, 1b) according to one of the previous claims, in which the production cycle includes the single-folded film (100) made of biodegradable thermoplastic or plastic material, unwound from a tubular coil which is cut in halves, obtained by longitudinally folding the film in half obtaining two specular edges (102, 103) facing each other, wherein the folding side corresponds to the base side (101) of the single-folded film (100), said production cycle being characterized in that downstream with respect to the unwinding station of the single-folded film (100) the string (200) is supplied with double or single edge, the string being made of the same material of the single-folded film (100), wherein said string (200) is longitudinally supplied with respect to the film (100) in such a way as to result in being parallel and close to the side of the opening (104), and wherein a following phase provides at least one welding (30), orthogonal with respect to the advancing direction of the film (100) with a contextual execution of an intermediate preliminary-cut (40) in correspondence with the overlapped edges (102, 103) defining the dividing line between one bag and the following bag (1a, 1b).
Closing method of the bag (1a, 1b) according to claims 1 to 3, characterized in that the bag (1a, 1b) is curled in correspondence with the opening (104), making the string (200) hanging with the head (210) on one of the sides of the bag (1a, 1b), so that the head (210) is wound around the curled portion of the opening (104) forming at least one neck (211) to be laid under the rest portion (212) and pulled as much as needed to obtain the closure of the opening (104) by means of a bottleneck.
Waste bag with a closing string device and closing method of the bag and production method of the bag, according to the previous claims, characterized in that the material from which the bag (1a, 1b) and the string (200) are obtained is a biodegradable thermoplastic material.