KR20040019340A - Easy opening, re-closeable gag - Google Patents

Abstract

The bag 10 for storing products such as powder or granular detergents, pet food, coffee, grains, etc. preferably has a perforation 28 which is formed by laser scoring to facilitate opening. The bag also preferably has means 32 for reclosing after the user first opens it by the hook and loop fastening system.

Description

Easy opening, re-closeable gag

Cross Reference of Related Application

This application claims 35 U.S.C. No. for US Provisional Application No. 60 / 307,353 filed on July 23, 2001 (Agency Case # 8644P). To claim priority under section 119 (e).

Today, flexible bags are used to package a wide variety of consumer products, including granular detergents. To be useful as a packaging material, such bags must not be opened during shipment and handling in a store. Currently commercially available detergent bags have several drawbacks. First, present bags have difficulty opening without the use of scissors, knives or other tools. When a consumer tears open the bag, it often results in the contents spilling. In addition, the text printed on the bag and back may be stretched and distorted during opening.

Second, current detergent bags do not provide an efficient and effective means for reclosing the bags once opened. Many consumers require bag reclosability. This is especially true for large packaging materials. The methods of reclosing these bags to date have not been satisfactory. These methods include zippers and adhesive tapes as well as simply folding mechanisms. The main disadvantage of the above described method is that, due to contamination of the reclosing means by the contents of the bag, the reclosing means cannot form a reliable and reusable seal. Also, simple folding mechanisms cannot prevent product leakage.

Third, as the contents of the bag are gradually consumed, it is desirable to be able to adjust the closure means to seal the bag more completely. Current flexible detergent bags do not provide a means of adjustment for tight and reliable sealing.

Thus, there is still a need for flexible bags for packaging consumer products that are easily opened without the use of knives, scissors or other tools. There is also a need for a mechanism that enables the bag to be securely resealed after being opened by the consumer. Reclosure appliances shall not be affected by any contamination. In addition, there is still a need for reclosable means that are adjustable to provide reliable and reliable sealing as the contents of the bag are reduced.

The present invention relates to bags having a perforation line for use in storing products such as, but not limited to, powder or granular detergents, pet food, coffee, cereals, and the like, which provide easy opening. More specifically, the bag further comprises a control means for reclosing.

1 is a horizontal perspective view of a first embodiment of a bag of the present invention;

2 is a vertical perspective view of a first embodiment of a bag of the present invention;

3 is a vertical perspective view of a first embodiment of the present invention;

4 is a horizontal perspective view of a second embodiment of a bag of the present invention;

5 is a horizontal perspective view of a second embodiment of a bag of the present invention;

6 is a horizontal perspective view of a third embodiment of a bag of the present invention;

Fig. 7 is a vertical perspective view in a closed position of the third embodiment of the bag of the present invention.

FIG. 8 shows a typical graph obtained using ASTM D-882 for measuring tensile strength. FIG.

FIG. 9 shows a typical graph obtained using ASTM D-5733 for measuring trapezoidal tear strength for a single specimen.

10 is a vertical perspective view of a fourth embodiment of the present invention.

Fig. 11 is a vertical perspective view in a closed position of the fourth embodiment of the present invention.

The present invention satisfies the aforementioned needs by providing a flexible bag that is easy to open. The bag also has adjustable reclosing means.

The flexible bag according to the first aspect of the present invention includes a front panel and a rear panel each having an upper edge and a lower edge, two side panels folded inward, an upper portion which is sealed by combining the front panel and the rear panel, and A lower portion, wherein the upper portion is further formed with a tear line, at least a portion of one panel of the bag remains undamaged by the tear line. Perforation allows for complete and controlled rupture of the bag.

The bag further includes means for reclosing the bag after the initial opening by the consumer. The reclosable means can be adjusted to provide an effective and reliable closure as the contents of the bag are consumed.

All percentages, ratios, and ratios used herein are by weight unless otherwise indicated. All documents cited herein are hereby incorporated by reference in their entirety.

Reference will now be made in detail to the preferred embodiments of the invention shown in the accompanying drawings. As can be seen, the terms front and back used herein to describe the panel of the bag are used only for the purpose of orientation and may otherwise be reversed. As will be described more fully hereinafter, the present invention relates to a flexible bag containing granular, powder or other contents, preferably granular detergents, with cutouts to facilitate opening. A particularly preferred bag 10 made in accordance with the invention is shown in FIG. 1. The bag 10 has a front panel 12, a back panel 14, and side panels 16, 18, each of which is shown having a top edge 20 and a bottom edge 22. The bag 10 also has an upper portion 24 and a lower portion 26 which are sealed by joining the front panel 12 to the back panel 14 along the upper edge 20 and the lower edge 22. Bag 10 has a perforation 28, at least a portion of at least one of panels 12, 14 having no perforation 28. In a preferred embodiment, the perforations 28 are formed over two side panels 16 and 18 and the front panel 12 or back panel 14.

FIG. 2 shows the same bag 10 as in FIG. 1, with the cut line 28 being opened by pulling either side of the cut line 28.

3 shows the same bag 10 as in FIG. 1 and further comprises a reclosable means 30 (not shown in FIG. 3) 32. The reclosable means 30, 32 may be any mechanical fastening mechanism, preferably consisting of a hook and loop fastening system, one of the resealable means 30 or 32 being a hook Element and the loop element. It is within the scope of the present invention that two elements may be reversed. 4 shows the reclosable means 30 as a small strip attached to the front panel 12 adjacent the top edge 20. It is also within the scope of the present invention that the reclosable means consists of a hook and hook system rather than a hook and loop system.

5 shows the reclosable means 32 as a vertical strip attached to the back panel 14. 6 shows another example of a reclosable means 30. Figure 7 shows the bag in the closed position.

Another preferred embodiment of a reclosable system is shown in FIGS. 10 and 11. One element 30 of the reclosable system is attached to the front panel 12 or back panel 14 with the hook or loop portion facing the panel. A portion of element 30 remains unattached. Closing the bag is accomplished by two successive folds of the upper portion 24 of the bag 10. The first folding causes the non-attached portion of the reclosable system to protrude so that this portion can be fitted to the second element of the system. The second fold substantially joins the mechanical fasteners together. 11 shows this alternative embodiment in a closed position.

Bag material

Bags of the present invention include, but are not limited to, polymeric films, woven materials, nonwoven materials, preferably polyethylene films, more preferably monolayers, coextrusions, two layer laminates, three layer laminates, and It is formed of an elastic material comprising a metallized laminate, all of which may or may not have a lacquer coating. The bag according to the invention can be formed by any method known in the art. One method of forming a flexible bag from continuous web material is disclosed in US Pat. No. 5,054,619 to Muckenfuhs and known in the art.

Perforation

The easy opening of the bag according to the invention is due to the fragility of the film material in the required bag rupture or separation trajectory.

The tear line is such that at least a portion of one panel of the bag is not vulnerable by the tear line. This prevents the entire upper part of the bag from detaching when opened. After opening, a flap formed by cutting the perforation line provides the bag with a handle or gripping area that allows the consumer to hold the bag while loading the product. This feature provides better operability of the bag and allows for easy loading of the contents.

The perforations will degrade the film in a manner that can withstand normal filling, packaging and handling but can be easily opened by the consumer. This operation is accomplished by reducing the film's inherent trapezoidal tear strength. Reduction of trapezoidal breaking strength is also likely to entail a loss of tensile strength.

The perforations are as follows: a) ASTM D-882 Standard Test Method for Tensile Properties of Thin Plastic Sheeting, and b) ASTM D-5733 Standard Test Method for Breaking Strength of Nonwoven Fabrics by Trapezoidal Procedure. Is characterized by. Graphs of the results of these test methods are illustrated in FIGS. 8 and 9. The samples used to generate FIGS. 8 and 9 are taken from the perforation line 28 as shown in FIG. 1. According to ASTM D-882 and ASTM D-5733, the tear line 28 should be parallel to the shortest side (ie, width) of the sample. Tear lines 28 should be formed over the entire width of the sample and should be centered relative to the sample length. The slot for initiating the cutting of the trapezoidal fracture sample should be at the top of the tear line 28.

The perforation line is characterized by three parameters obtained from the standard test method described above. The first parameter is the yield stress value. Referring to FIG. 8, the graph shows the approximate yield stress value (shown as Y1 in FIG. 8) versus the approximate yield stress value (shown as Y2 in FIG. 8) of the film without the cutout. In ASTM D-882 tensile test, the yield stress value of the cut line film should be at least 90% of the yield stress value of the film without cut line. Second, the final or burst stress value (shown as R2 in FIG. 8) of the cut line formed film should be at least 90% of the yield stress value Y1 of the film without the cut line formed.

Third, the average trapezoidal breaking force of the perforated film according to ASTM D-5733 should be less than 4 Kgf. FIG. 9 shows a typical graph obtained using ASTM D-5733 to measure the trapezoidal fracture strength in a single specimen cut line film. With reference to FIGS. 8 and 9, the values representing force, elongation (FIG. 8) and extension (FIG. 9) in the figures should be considered as examples only, not as limiting the invention.

Additionally, the cutout line may include a pattern. Such a pattern may take the form of a continuous line, a dotted line or a combination thereof. However, the best pattern is a dashed line consisting of a plurality of scored parts. The length of each scored portion may vary in the range of about 0.12 mm to 4.4 mm, preferably about 0.3 mm to 2 mm, most preferably about 0.6 mm to 1 mm. The distance between adjacent scored portions may vary in the range of about 0.4 mm to 4 mm, preferably about 1 mm to 3 mm, most preferably about 1.5 mm to 2 mm. The depth of the scored portion may vary depending on the thickness of the film.

A starting notch may be provided at a point along the perforation line. The starting notch provides a certain area, which makes it easier to tear as the scoring becomes deeper. If the cutout extends over the back panel with the vertical seal, the starting notch is easily torn through the multiple plies of the vertical seal to the cutout.

How to form a perforated line

Perforations can be formed using methods including but not limited to scoring, perforation, chemical treatment, preferably laser scoring, laser perforation, mechanical scoring, mechanical perforation, embossing methods, or a combination of these methods. The cutout is preferably formed in the film before it is formed into a bag.

One method of forming a cutout line in a flexible film uses at least one laser. First, a laser beam with sufficient wattage to evaporate a portion of the film material is concentrated in the film. The use of laser technology allows for very precise control of depth or penetration from very shallow scoring to complete the perforation of the film. Lasers using any form of electromagnetic radiation can be used. Lasers suitable for use in the present invention include lasers based on CO2 gas.

The speed of the film and the movement of the laser beam depend on the type of film used as well as the required depth and pattern of scoring. Suitable methods for laser scoring a film include US Pat. Nos. 3,626,143, 3,790,744 and 3,909,582 to the American Can Company, and US Patents to the American National Can Company. 5,158,499 and 5,229,180, US Patent No. 5,001,325 to LPF Verpakkingen BV, US Patent No. 4,743,123 to Wavin BV, and US Pat. And Japanese Patent Nos. 09133018, 07008283, and 06103200 to Dainippon Printing Company.

Another suitable method for forming a cut line is the use of a blade. The blade is installed on an engraving cylinder, which is mounted directly on the film processing machine so that a cut is made before the bag is formed. Different blade patterns can be used to obtain different patterns at the perforations. In addition, the pressure applied to the blades is varied during the process to control the size and depth of the cut to ensure easy opening of the bag.

Embossing is another alternative method for forming a cut line. Embossing techniques weaken specific areas of the film by pressure, temperature, time and strain profile. The required result is achieved by changing the thickness and / or material organization in the embossed trajectory. The basic equipment used for embossing consists of a sealing jaw that can press against the back plate. The deformation profile or pattern is fixed to the jaws and heated. The film is pressed between the deformation profile and the back plate. The key variables known to affect this process are heating temperature, cooling temperature, pressure, heating time, cooling time, film tension during embossing, film tension after embossing, back plate material, back plate thickness, back plate temperature, jaw pattern and Joo thick. The embossing device is installed after the unwinding station of the film and is preferably integrated into the packaging equipment line. Suitable examples of embossing are disclosed in US Pat. No. 5,878,549 to American National Can Company.

Reclosable system

Reclosable systems must be resistant to contamination by the contents of the bag. The main purpose of a reclosable system is to protect the granular product in the bag from leaks, moisture, and other external factors that may affect the integrity of the product. Such a reclosable system is a mechanical fastener, preferably hook and loop or hook and hook type, that is attached to a flexible bag so that the consumer can open and reliably close the bag a number of times the product is used in the bag. It includes.

The system is constructed by placing the fastening material on opposing panels of the bag. Other forms may be contemplated, but in the preferred embodiment the panels are front panel and back panel. Fasteners may be disposable or industrial materials. In order to optimize cost, it is necessary to use disposable materials. Mechanical fasteners can be of any shape and size and can be of any arrangement. The particular type of reclosable system elements should be such that the bag can be sealed over the entire use of the product contained in the bag. Sealing means that the product does not spill when the bag is tilted to the side. In particular, the reclosable system is characterized by the energy required to detach one element of the fastener from the other. This energy should not be less than 2.4 Kgfmm per Kg of product in the bag.

The reclosable system is intended to work with the above-mentioned easy opening which facilitates the opening of the bag. At least one element of the mechanical fastener is disposed on one panel of the bag and the other element of the fastener to which it is coupled is disposed on the opposite panel of the bag. Preferably one element of the mechanical fastener is a vertical strip. The top of the bag (with the small elements of the fastener) is dried up so that the two fastener elements join and tightly seal the bag as the product is consumed. As the product is consumed more, the fastener is closed further down vertically in order to seal tightly. A variation of this design is a button to button closure. This means that the mechanical fastener can consist of two separate buttons for carrying out the sealing. In this case, the seal is a fixed seal instead of an adjustable seal.

Such mechanical fasteners may be attached to the bag by an adhesive. The adhesive may be a hot melt or pressure sensitive adhesive. The hot melt adhesive is applied to the mechanical fastener just before the elements of the mechanical fastener are applied to the bag. The pressure sensitive adhesive is attached to the fastener as a single piece.

The application of this mechanical fastener to the bag can be made in other ways. One way is to attach this fastener to the film before the bag is produced. In this case, the elements of the mechanical fastener are attached to the film while the film roll is being manufactured or while the film roll is unwound from the machine. The mechanical fastener may also be attached to the bag after the bag is formed.

While specific embodiments of the invention have been shown and described, it will be apparent to those skilled in the art that various modifications and changes can be made without departing from the spirit and scope of the invention. Accordingly, it is intended that all such changes and modifications falling within the scope of the invention be included in the appended claims.

Claims (10)

A front panel and a rear panel each having an upper edge and a lower edge, two side panels folded inwardly, and an upper portion and a lower portion formed by combining the front panel and the rear panel, and the upper portion has a perforated line Further formed, the cutout is formed over one of the front panel and the back panel and both side panels, wherein the cutout is preferably chemical treatment, laser scoring, laser drilling, mechanical scoring, mechanical drilling, embossing method or these And a cutout is formed using laser scoring. More preferably, the cutout line is formed using laser scoring. The bag of claim 1 further comprising means for reclosing the bag after opening. A front panel and a rear panel each having an upper edge and a lower edge, two side panels folded inwardly, and an upper portion and a lower portion formed by combining the front panel and the rear panel, and the upper portion has a perforated line Further formed, at least a portion of the upper portion of one panel is unaffected by the perforation line and further comprises means for reclosing the bag after initial opening, said reclosing means preferably hook and loop A mechanical fastening system selected from the group consisting of a fastening system, a hook and a hook fastening system, and combinations thereof, more preferably a phrase is printed on at least one element of the fastening system, even more preferably the fastening On at least one element of the system a description of the use of the contents of the bag is printed The bag characterized by. 4. The reclosing means of claim 3, wherein the reclosing means consists of a hook and loop fastening system comprising a hook element and a loop element, the hook element being located on the front panel of the bag and the loop element being located on the back panel of the bag. Bag characterized in that. 4. The reclosing means of claim 3, wherein the reclosing means consists of a hook and loop fastening system comprising a hook element and a loop element, the loop element being located on the front panel of the bag and the hook element being located on the back panel of the bag. Bag characterized in that. The yield stress value measured according to ASTM method D-882 of the bag having the perforation line is at least 90% of the yield stress value of the bag before the perforation line is added. back. The bag according to claim 1, wherein the final or burst stress value of the bag, measured according to ASTM Method D-882, is at least 90% of the yield stress value of the bag before the tear line is added. The bag as claimed in claim 1, wherein the bag has an average trapezoidal breaking strength of less than 4 Kg as measured according to ASTM method D-5733. The bag as claimed in claim 1, further comprising a laundry detergent. The method of claim 1, wherein the perforations are formed using a method selected from the group consisting of chemical treatment, laser scoring, laser drilling, mechanical scoring, mechanical drilling, embossing methods, or a combination thereof. The perforation line is preferably formed using laser scoring, the perforation line more preferably comprises a pattern consisting of dashed lines comprising a plurality of scored portions, the length of each scored portion being from about 0.12 mm to 4.4 mm, preferably in the range of about 0.3 mm to 2 mm, most preferably about 0.6 mm to 1 mm, and the distance between adjacent scored parts is about 0.4 mm to 4 mm, preferably about 1 mm to 3 mm, most preferably about 1.5 mm to 2 mm.