RU2616855C1 - Sheet material for reforming sealed packaging - Google Patents

Abstract

FIELD: packaging industry.

SUBSTANCE: invention relates to sheet material for reforming sealed flexible packaging. Packaging comprises a sheet of flexible material and has the first configuration, which is a substantially flat configuration, and the second configuration, which is a folded and tight configuration. In the flat configuration both before and after sealing the user can use a sheet as a working surface. Flexible material contains a foldable part and sealing areas arranged on the first and second parts of the packaging on opposite sides of the foldable part. If sealed packaging is desired, user can fold the sheet substantially around the foldable part, so that the sealing areas substantially align with each other. Then the user can press back-to-back the aligned and connected sealing areas to ensure sealing. For access to the sealed content user can simply pull folded sections of flexible material substantially from each other, to separate engaged sealing areas.

EFFECT: disclosed is a sheet material for reforming sealed packaging.

30 cl, 10 dwg, 18 tbl

Description

Cross references to related applications

This application claims priority to U.S. Patent Application No. 61/794,029, filed March 15, 2013, the entire contents of which are incorporated herein by reference.

Technical field

The present application relates essentially to a sheet material capable of forming a flexible packaging, and more particularly to a sheet material capable of folding into a resealable flexible packaging.

State of the art

One type of packaging known in the art is a bag or bag, which essentially consists of a flexible plastic or film. This type of packaging is substantially rectangular and sealed on three sides, so that the packaging has an open neck to provide access to the inside of the packaging. In one form, a packaging uses a valve made of material extending along one side of the neck and a pocket on the other side of the neck that receives a valve for closing, similar to an envelope. In another form, the package includes a zipper type with a slider or a press-on zipper on the neck that is capable of sealing the package.

Although these packages are suitable for many purposes, it can be difficult to place contents such as sandwiches that are large and bulky in relation to the neck. This is especially true for dirty or non-uniform content. In one illustrative example, to store a peanut butter and jam sandwich, a user needs to make a sandwich and then place it in a package. In order to keep the sandwich intact, the user clamps the sandwich on both sides and manually enters the package to place the sandwich in it. If a sandwich leaks on one side, peanut butter and / or jam may spread on the inside of the package or around the neck, causing unwanted contamination.

SUMMARY OF THE INVENTION

This document describes a package including a sheet of flexible material, which has a first configuration representing a substantially flat configuration and a second configuration representing a folded and sealed configuration. In a flat configuration, both before and after use, the user can use the sheet to prepare the contents as a work surface or substrate. Then, if it is desired to provide airtight packaging, the user can fold the sheet around the desired contents to seal the contents therein. Preferably, the flexible material includes a foldable part or bend line, previously applied, marked with a sign or imaginary, and sealing areas located on opposite sides of the bend line. Thus, if a sealed package in a folded configuration is desired, the user can fold the sheet substantially around the folding part so that the sealing areas are substantially aligned with each other. The user can then press the aligned and close-fitting sealing areas to provide sealing. To access the sealed contents, the user can simply pull the folded sections of the flexible material substantially apart to separate the sealing areas. The user can then advantageously use the sheet in a flat configuration after opening as a work surface or substrate.

In a first form, the package includes a sheet of flexible material that includes edges, an inner surface, and an outer surface. The folding part is located across the sheet between the edges and divides the sheet into first and second flexible panels. The adhesion bands are located on the inner surface of the sheet along its side edges, and the end adhesion bands are located on the inner surface of the sheet along its side edges. The clutch bands include the first and second opposite parts of the clutch strip located on the first and second panels, respectively, configured to align and engage respectively to form a sealed package by folding the first and second panels together with respect to the folding part. The package further includes one or more opposite leaky valves on the outer edges of the inner surfaces of the folded sheet located along each side of the sealed package between the edges of the sheet and the adhesion bands, the opposite leaky valves on the outer edges being able to grab them and pull them in different directions to separate the first and a second part of the clutch strip to separate the engaged clutch strip along the edges.

The package may further include one or more intermediate engagement bands extending between at least one of the lateral engagement bands and the end engagement bands. One or more intermediate engagement bands are configured to tightly engage and provide the user with the ability to divide the sealed interior space of the package into a plurality of sealed interior spaces of the package.

In a second form, the package includes a sheet of flexible material and a low-adhesive binding agent. The sheet has edges and a foldable part between them. The foldable part divides the sheet into first and second flexible panels, and the low-adhesive bonding agent is located on the inner surface of the sheet along the edges of the first and second flexible panels. The bonding agent is made with the possibility of alignment and engagement as a result of folding together the first and second panels of the sheet relative to the folding part. Therefore, to form an airtight package in a second configuration, the user can fold the sheet relative to the foldable part so as to substantially align the low-adhesive bonding agent located on the first and second flexible panels and press to seal the sheet around the contents. A non-adhesive binding agent may have the properties and compositions described herein.

In a third form, the package includes a sheet of flexible material and complementary connecting components such as mating strips and a resealable bonding agent. The sheet has end edges, side edges, an inner surface and an outer surface. The folding part is located across the sheet to divide the sheet into first and second flexible panels. In this form, each of the symmetrical sealing regions includes one of the complementary coupling components and a resealable coupling agent. The first connecting component is attached to the sheet adjacent to one end edge, and the second connecting component is attached to the sheet adjacent to the other end edge. Thus, the first and second connecting components are placed on opposite sides of the sheet on both sides of the fold line when the sheet is in a flat configuration. The resealable coupling agent includes opposed side strips located on the inner surface of the sheet and extending between the first and second connecting components adjacent to the side edges of the sheet. Therefore, in order to form an airtight package, the user can fold the sheet relative to the fold line so as to substantially align the first and second mating portions and to substantially align the resealable bonding agent. The package further includes opposing leaky valves on the outer edges of the inner surfaces of the folded sheet, located along each side and the end of the sealed package between the side edges of the sheet and the adhesion strips and the end edges and connecting components, respectively. Opposite leaky valves on the outer edges are configured to grab and pull them in different directions to separate the first and second parts of the clutch strip to separate the engaged clutch strip along the side edges and the hooked connecting components along the end edges.

In another approach, the resealable binding agent in the forms described above may be a low-adhesive binding agent, the composition of which is described in more detail below. A poorly adhesive binding agent has a stronger bond with itself than with other surfaces or materials. Thus, a slightly adhesive binder in the sealing areas can maintain sealing properties even if the binder comes into contact with the contents of the package.

Brief Description of the Drawings

In FIG. 1 is a perspective view of a first form of a resealable packaging with a flexible sheet in a flat configuration with a resealable bonding agent adjacent to its edges;

in FIG. 1A is a perspective view of a second form of a resealable packaging with a flexible sheet in a flat configuration with a re-sealable bonding agent adjacent to its edges and intermediate re-sealable adhesion bands;

in FIG. 2 is a perspective view of a resealable packaging shown in FIG. 1, with a sheet in a folded and sealed configuration;

in FIG. 3 is a perspective view of a roll of flexible material divided into sheets for the resealable packaging shown in FIG. 1 by means of thin parts directed transversely through a flexible material;

in FIG. 4 is a perspective view of a third form of a resealable package with a flexible sheet in a flat configuration with interlocking locking parts at opposite ends of the sheet and a re-sealing binding agent extending between the locking parts on the sides of the sheet;

in FIG. 4A is a perspective view of a fourth form of resealable packaging with a flexible sheet in a flat configuration with a re-sealable bonding agent adjacent to its side edges, complementary connecting components adjacent to its end edges and intermediate re-sealable adhesion bands;

in FIG. 5 is a perspective view of the resealable packaging shown in FIG. 4, with a sheet in a folded and sealed configuration;

in FIG. 6 is a perspective view of a fifth shape of a resealable package with a flexible sheet in a flat configuration with a re-sealable bonding agent adjacent to its edges;

in FIG. 7 is a perspective view of a resealable packaging shown in FIG. 6, with a sheet in a folded and sealed configuration; and

in FIG. 8 is a perspective view of a roll of flexible material divided into sheets for the resealable packaging shown in FIG. 6 by means of thin sections directed transversely through the flexible material.

DETAILED DESCRIPTION OF THE INVENTION

In general terms, in accordance with these various approaches, the apparatus and methods described herein describe a resealable packaging configured to transition between a first, flat and open configuration and a second, folded and sealed configuration, various forms of which are shown in FIG. . 1-8. In the examples of forms described herein, a bonding agent, an interlocking closure, or combinations thereof along the outer edges of the film web can be advantageously used to open and close between the first and second configurations.

The first example of the form is shown in detail in FIG. 1 and 2. The resealable package 10 includes a sheet 12 shown in a first substantially flat or open configuration. This form of packaging uses a flexible packaging film or plastic sheet material. The packaging sheet material may be a flexible single or multilayer film, sheet or other material, including materials such as polyethylene terephthalate (PET), polypropylene (1111), which may or may not be oriented along one or two axes, linear low density polyethylene (LLDPE), ethylene vinyl alcohol (EVOH) and / or polyethylene (PE) as a few examples. The sheet 12 is divided into the first part of the sheet 14 and the second part of the sheet 16, in some approaches, by the fold line 18 extending across the sheet 12. In other approaches, the sheet is divided into parts 14, 16 by means of a folding area or part 18. An optional fold line 18 can be pre-marked on sheet 12, for example by mechanical folding, marking, continuous or intermittent, and / or have a designation, such as printing, marking, etc. on sheet 12 with a clear indication of its location. The packaging 10 thus formed can be folded relative to the fold line or the folding part 18 so that the first and second parts 14, 16 are brought into contact with each other or are adjacent to each other.

In one approach, sheet 12 includes first and second end edges 20, 22 and first and second opposite side edges 24, 26. The first opposite side edges 24 form the side edges of the sheet part 14 and are connected to the second opposite side edges 26 that form the side edges of the part of the sheet 16, on the fold line or foldable portion 18, so that the side edges 24, 26 extend continuously between the end edges 20, 22. It should be understood that the example of the shape shown in the figures is just one example of a resealable package 10 and Sheet 12. Other sizes, shapes, and configurations are also possible.

In the first illustrated form shown in FIG. 1 and 2, the package 10 further includes first and second adhesion zones 28, 30 located on the periphery or around the perimeter of the first and second parts of the package or panels 14, 16, respectively. As described herein, the binder can be applied or printed on sheet 12 by any suitable method. The first and second adhesion zones 28, 30 are substantially symmetrical with respect to the fold line or folding part 18, so that the zones 28, 30 are essentially aligned when the first and second parts of the package 14, 16 are rotated or folded together. More specifically, each of the first and second engagement zones 28, 30 may include an end engagement portion 32 extending adjacent to the end edges 20, 22, and opposing lateral engagement portions 34 extending adjacent to the first and second opposite lateral edges 24, 26. B in one form, the adhesion zones 28, 30 have a substantially uniform width around the periphery of the sheet 12, ranging from about 0.64 centimeters to about 3 centimeters (from about 0.25 inches to about 1 inch), and in some approaches, approximate no 1 centimeter (about 0.5 inches).

As shown in the figure, the opposite side portions 34 of the first and second engagement zones 28.30 are connected to each other via a fold line or folding part 18 and connected to the corresponding end engagement portion 32, so that the first and second engagement zones 28, 30 provide a continuous boundary adhesion at the periphery of the sheet 12 and also provides a substantially free of binding agent inner surface 36 covering both parts of the sheet 14, 16. In the planar configuration shown in FIG. 1, the inner surface 36 can be used as a work surface. For example, the inner surface 36 can be used as a preparatory surface for creating a sandwich or the like. or use as a backing during lunch.

If desired, adhesion zones 28, 30 may include serrated edges or discontinuous parts, i.e. strips of non-sticking outer parts to facilitate separation of the adhesion zones 28, 30 when they are hermetically connected to each other. These teeth, stripes, etc. may extend along the length of the engagement zones 28.30, may be limited by one or both side portions 34, or one or both side portions 32, selected portions thereof, or one or both corners connecting the side and end portions 34, 32.

Although sheet 12 is shown as being substantially rectangular and configured to fold into a substantially rectangular sealed package, other suitable shapes can be used as described above. For example, the sheet 12 may be configured to fold into a triangular sealed package with corresponding adhesion zones, the sheet may also be essentially round or oval or other symmetrical shape.

In this configuration, the user can prepare the contents of the package, if necessary, to decompose the contents on the inner surface 36 in the first or second part. The user can then fold the opposite part relative to the fold line or foldable part 18, essentially align the first and second adhesion zones 28, 30, and compress the aligned zones 28, 30 to seal the first and second parts of the package 24, 26 tightly together to form a sealed inner space 38 and, thus, form or assemble a sealed bag or package, as essentially shown in FIG. 2. When the user wants to open the package, the first and second parts 14, 16 can be pulled essentially from each other from any edge, except for the fold 18, to gain access to the contents and / or use the uncomplicated inner surface 36 as a substrate, etc. .

In one form, the adhesion zones 28, 30 are spaced apart from adjacent edges 20, 22, 24, 26 of sheet 12, so that binder-free parts, flaps or edges 40 are present along all the edges of the sealed bag or package, except for the folded edge 18, as shown in FIG. 1 and 2. These bonding agent-free parts 40 provide non-stick grip surfaces so that the user can grip and separate the first and second adhesion zones 28, 30 when they are sealed together. The user can advantageously choose any attached edge for opening, and the user is not limited to opening one neck, which was characteristic of the previous flexible packaging. In fact, the user can even open 2 or more edges at the same time through the parts 40. Alternatively, only the end sections of the clutch 32 can be separated from the end edges 20, 22, or only parts of the end and side sections of the clutch 32, 34 can be moved deeper, or they can have non-sticking grip portion.

As shown in FIG. 1 and 2, the first and second parts of the package 14, 16 are substantially symmetrical. However, this is not necessary since only the first and second adhesion zones 28, 30 are substantially symmetrical, so that they are hermetically sealed when the first and second parts 14, 16 are folded relative to the fold line 18. Thus, as shown in FIG. 6-8, one of the first and second parts may be longer so that a longer valve 40 is present, which is easier to grip, extending from the sealed configuration. Moreover, the first and second parts can have many shapes and sizes to ensure uniqueness and attract consumer attention. The non-stick portions, flaps, or edges 40 can be any size relative to the width of the strips or adhesion zones 28, 30. In some approaches, the width of the parts 40 ranges from about 0.158 centimeters to about 0.64 centimeters (from about 1/16 inch to about 1 / 4 inches), and the ratio of the width of the bonding agent 28, 30 to the width of the parts 40 may be from about 1: 1 to about 16: 1. In other approaches, portions 40 can be up to about 3 centimeters (up to about 1 inch), and portions 40 can be wider than binder 28, 30.

As shown in FIG. 1A, an alternative shape of the sheet 12 is similar to the sheet shown in FIG. 1, and thus has the same reference numbers for common components. In this approach, the sheet 12 may further have one or more strips of a binder agent 42 deposited on the inner surface 36 and extending between the end portions of the clutch 32; one or more symmetrical pairs of bands of the bonding agent / bonding agent 44 deposited on the inner surface and extending between the side portions of the clutch 34; or any combination thereof. These strips 42, 44 allow the user to divide the sealed inner space 38 into many smaller sealed inner spaces 36A by aligning and compressing the desired strips 42, 44 when folding sheet 12. This can advantageously allow the user to separately store different contents within the same package in an individually sealed area, areas or packages. As shown in the figure, the bands 42, 44 extend substantially perpendicular to each other and to the adhesion bands 28, 30, 32; however, these strips 42, 44 may also extend obliquely to each other, for example diagonally across the sheet 36.

In the second form shown in FIG. 4, 4A and 5, the package 50 is shown having many similar features with the package shown in FIG. 1, 1A and 2. Thus, for simplicity of description, like reference characters will be used for like elements. The package 50 in this form includes a sheet 12 shown in a substantially flat or open configuration. The sheet 12 is divided into the first part 14 and the second part 16 by means of a fold line or a foldable part 18 transversely passing through it. As shown in the figure, the sheet 12 includes first and second end edges 20, 22 and first and second opposite side edges 24, 26. The first opposing side edges 24 are connected to the second opposing side edges 26 on the fold line 18, so that the side edges 24, 26 extend between the end edges 20, 22.

The package 50 of this form includes the first and second adhesion zones 52, 54 located in the first and second parts of the package 14, 16, respectively. The first and second adhesion zones 52, 54 are substantially symmetrical with respect to the crease line 18, so that the zones 52, 54 are substantially aligned when the first and second parts of the package 14, 16 are rotated together. More specifically, each of the first and second adhesion zones 52, 54 includes opposing lateral clutch portions 56 extending adjacent to the first and second opposing lateral edges 24, 26. In the illustrated form, the adhesion zones 52, 54 have a substantially uniform width in the range from about 0.64 centimeters to about 3 centimeters (from about 0.25 inches to about 1 inch), more preferably about 1 centimeter (about 0.5 inches).

The package 50 further includes a first and second non-stick complementary connecting components 58, 60 extending adjacent the end edges of the package 20, 22, respectively. Non-adhesive connecting components 58, 60 are made with the possibility of tight joining, connection or meshing when compressing them together. In one approach, the non-adhesive connecting components may be a recess and a trough, a contact tape, a latch and a zipper, with a slider as a few examples. As shown in the figure, the opposite side portions of the clutch 56 extend between the ends 62 of the connecting components 58, 60 and the fold line 18, so that there is a continuous continuous length of binder between the respective ends 62 of the connecting components 58, 60. Then, when the first and second parts 14, 16 rotate or fold together relative to the fold line or foldable part 18, the first and second engagement zones 52, 54 and the connecting components 58, 60 are aligned, respectively. The user can then apply compression pressure to the grip zones 52, 54 and the connecting components 58, 60, respectively, to seal the package in the airtight configuration shown in FIG. 5. In an additional approach, the connecting components 58, 60 can be hermetically connected to each other using a zipper or the like.

As shown, the mating members 58, 60 and the first and second engagement zones 52, 54 are connected to provide a continuous, closed, airtight boundary forming the inner surface 64. In a flat configuration, the inner surface 64 can be used as a work surface. For example, the inner surface 64 can be used as a preparatory surface for creating a sandwich, etc. or as a substrate.

In this configuration, if necessary, the user can prepare the contents of the package, decompose the contents on the inner surface 64 in the first or second part thereof. The user can then fold the opposite part relative to the fold line 18, essentially align the first and second adhesion zones 52, 54 and the mating elements 58, 60 and compress to tightly engage the first and second parts of the package 14, 16 to form a sealed inner space 66. As shown in FIG. 4A, a package 50 of this shape may further have one or more optional binding agent strips 42 applied to the inner surface and extending between the connecting components 58, 60; one or more symmetrical pairs of optional binding agent strips 44 applied to the inner surface and extending between the lateral portions of the clutch 56; or combinations thereof, as shown in FIG. 1A.

In one form, the connecting components 58, 60 are spaced apart from adjacent end edges 20, 22 of the sheet 12, so that gripping surfaces 68 are present so that the user can separate the first and second mating elements 58, 60 when they are hermetically connected to each other. The user can then continue to pull the first and second parts 14, 16 substantially apart from the fold line 18 to separate the first and second engagement zones 52, 54. In addition, the lateral portions of the engagement 56 can be spaced from the side edges 24, 26, or portions of the lateral sections of the clutch 56 can be moved inland, or they may have non-sticking gripping portions 70 to provide an edge, valve, or gripping surface similar to those shown in FIG. 1, 1A and 2.

As shown in FIG. 4, 4A and 5, the first and second parts of the package 14, 16 are substantially symmetrical. However, this is not necessary since only the first and second engagement zones 52, 54 and the first and second mating elements 58, 60 are substantially symmetrical with respect to the fold line 18. Thus, one of the first and second parts may be longer so that a valve is present, which is easier to grasp, passing from a sealed configuration. Moreover, the first and second parts can have many shapes and sizes to ensure unusualness and attract consumer attention.

In a further form, a binding agent suitable for the sheets or packages described herein may be a low-adhesive binding agent, such as essentially described in US Patent Application No. 13 / 035,399, the contents of which are incorporated herein by reference in their entirety. A more detailed description of a specific non-adhesive binding agent is provided below.

In one aspect, the non-adhesive bonding agent for the adhesion zones 28, 30, 52, 54 and the sheet 12 is substantially constructed or has a composition to minimize adhesion of the bonding agent to undesirable surfaces or food materials while maintaining functioning as an effective resealable fastener. Thus, the binding agent has a unique composition or device to achieve the selected stickiness and separation, so that the fastener based on the binding agent can be opened and closed many times to seal the contents of the package 10, 50 during use by the consumer, but at the same time, the binder the agent should not be detached from the carrier film forming opposite inner surfaces of the sheet 12.

Thus, the binder can be a UV curable binder with a relatively low tack to minimize adhesion to unwanted surfaces, selected peeling strength when bonding or opening, sufficient to allow safe re-closing of the packaging 10, 50, and enough high peeling strength to allow re-opening and closing of the packaging 10, 50. At the same time, the bonding agent also has a strong bond with the carrier film from sheet 12, so that the binding agent did not detach when the package 10, 50 was opened. In one approach, the binding agent may include specific mixtures of a UV curable acrylic oligomer and a tackifier. In other approaches, the binder may include specific mixtures of a UV curable acrylic oligomer, a tackifier, and an elastomeric (rubber) component.

The bonding agent is preferably a UV-curable, pressure-sensitive adhesive bonding agent (PSA), which exhibits adhesion properties and low tack, but despite low tack, still forms a strong bond with the carrier film forming the opposite inner surfaces of the sheet 12. Essentially it is known that a material based on a binding agent, as a rule, is easier to attach to similar materials (self-adhesion) than to dissimilar materials. Suitable adhesion materials used herein essentially exhibit relatively low adhesiveness to unwanted surfaces, but at the same time, high bond strength to desired surfaces (so that they cannot be detached from the flexible front and rear panels) and relatively high bonding strength adhesion or self-adhesion to similar surfaces to keep the flexible package or bag closed, but still allow manual opening or peeling of the package. Selected materials based on a binding agent also allow separation or delamination from such similar materials, so that the adhesion layers can repeatedly exfoliate from each other without significant damage to the adhesion material and / or any substrate below. When the adhesion material is peeled off or peeled, the selected adhesion materials have sufficient intrinsic integrity and essentially peel off at the bonding bond interface substantially purely without substantially tearing off the material particles, pulling into the yarn, disengaging from the substrate and / or other significant material defects (i.e. rolling, etc.). Advantageously, bonding agent-based fasteners retain peeling strength, with opposing adhesion bands in contact with each other with an average peeling strength of more than about 31 Newton per meter (N / m) (about 80 grams per linear inch (gpli)), and preferably from approximately 31 to approximately 348 N / m (approximately 80 to approximately 900 gpli). Moreover, in some cases, the binding agent-based fasteners 14 retain a peel strength of more than about 31 N / m (about 80 gpli) and / or at least about 30 to about 200% of the average initial peel strength after five repeated tight closures and openings.

In another aspect, the package 10, 50 and the bonding agent are also designed to interact with each other so that the bond or peeling strength of the bonding agent with the inner surface of the sheet 12 is substantially higher than the peeling strength when opened between the layers of the bonding agent itself. Thus, the bonding agent essentially remains attached to the inner surfaces of the sheet 12, and essentially does not tear, stretch or detach from the inner surfaces of the sheet 12, when the consumer opens the package 10, 50 and the layers of the bonding agent are separated. For example, in one approach, the bond or peel strength of the binder with the carrier film of the package is greater than approximately 348 N / m (approximately 900 gpli) and is capable of withstanding many peeling and re-sealing cycles without being separated from the carrier film. In addition, the bonding agent is cured so that it can withstand more than 100 double passages with methyl ethyl ketone (MEK) as solvent (ASTM D5402-06).

The bonding agent is preferably a UV-curable, more preferably a UV-curable PSA, which exhibits adhesion properties and low tack, but forms a strong bond with the carrier film of sheet 12. It is generally known that a binder-based material is generally it is easier to attach to similar materials (self-adhesion) than to dissimilar materials. Suitable adhesion materials used herein substantially exhibit relatively low adhesiveness to undesirable surfaces, high bond strength to desired surfaces (so that they cannot be detached from the flexible first and second panels), and relatively high adhesive bonding or self-adhesion to similar surfaces for keeping the flexible packaging or bag closed, but at the same time maintaining the possibility of opening or peeling manually. Selected materials based on a binding agent also allow separation or delamination from such similar materials, so that the adhesion layers can repeatedly exfoliate from each other without significant damage to the adhesion material and / or any substrate below. When the adhesion material is peeled off or peeled, the selected adhesion materials have sufficient intrinsic integrity and essentially peel off at the bonding bond interface substantially purely without substantially tearing off the material particles, pulling into the yarn, disengaging from the substrate and / or other significant material defects (i.e. rolling, etc.).

The first component of the binding agent is one or more UV curable acrylate or acrylic oligomers. For example, the UV curable acrylic oligomer may be an acrylic or methacrylic acid ester having a plurality of reactive or functional groups (i.e., acrylic or methacrylic oligomers). Typically, the functional group includes one UV reactive center. UV reactive centers in most cases are double carbon bonds conjugated to another unsaturated center, such as an ester carbonyl group. In one approach, the UV curable acrylic oligomer is an ester of acrylic or methacrylic acid and a polyfunctional alcohol, which means that the oligomer contains more than one acrylated or methacrylated hydroxyl group on the main hydrocarbon chain of the oligomer. In one approach, the binding agent may include from about 1 to about 90% by weight. UV curable acrylic oligomers with functional groups from about 1.2 to about 6.0. In another approach, UV curable acrylic oligomers can have a functional group of from about 2.0 to about 3.0, and / or can be used in a binder in an amount of from about 20 to about 70% by weight.

In one form, the multifunctional UV curable acrylic ester is an ester of acrylic acid and vegetable oil having a number of reactive functional groups of 2.0 or more. In another aspect, the UV curable acrylic oligomer may comprise epoxidized soybean oil acrylate. In general, the amount of UV curable acrylic oligomers used, selected based on the preferred proportion of binder component (ACR) (described later herein), may affect the properties of the final binder. For example, when the amount of UV curable acrylic oligomer is too small based on the preferred ACR, the cure rate of the final binder is too low. On the other hand, when the amount of UV-curable acrylic oligomer is too large based on the preferred ACR, the final binder can cure normally, but have insufficient self-adhesion characteristics for repeated sealing.

The second component of the binding agent is a tackifier. In one approach, the binding agent may include from about 1 to about 65% weight. tackifying agent. In another approach, the tackifier may be present in an amount of from about 20 to about 65%. The tackifier may include a tackifying resin or a curable combination of polymer and monomer which, upon curing, can provide the desired tack levels and self-adhesive properties suitable for a resealable fastener. In one aspect, the tackifier may comprise an aliphatic acrylated urethane oligomer. Many other types of adhesive control agents suitable for UV curable PSA can also be used in a re-sealable clutch system.

An optional third component of the binding agent is an elastomeric or rubber component. In one approach, the elastomeric component may include at least one curable acrylated (i.e. modified with acrylic compounds) or methacrylated ester of an elastomeric polymer with hydroxyl end groups (i.e., an elastomeric polyol). This elastomeric component may include acrylic modified polybutadiene, saturated polybutadiene and / or elastic polyurethane. In one aspect, methacrylated polybutadiene can be used. When used in a binder, the elastomeric material can be used in amounts of from about 0 to about 20%. In one aspect, the elastomeric material is used in amounts of from about 5 to about 15%. Satisfying binders with the desired low-adhesive, re-sealing properties described herein can be obtained without an elastomeric component; however, it is believed that the elastomeric component contributes to optimal coating performance. The optimal characteristics of the binding agent can be set by properties, such as, for example, self-adhesion, tack, viscosity and curing rate. The elastomeric component is suitable for controlling the properties of peeling strength, adhesion to the substrate, increasing elasticity, controlling viscosity and modulating the curing rate.

The average initial peeling strength of a properly cured binder, determined by the test in accordance with method ASTM D3330 / D3330M-04, method F, can be from about 31 N / m to about 348 N / m (from about 80 gpli to about 900 gpli ) and in particular from about 108 N / m to about 309 N / m (from about 280 gpli to about 800 gpli). The bonding agent is also configured to maintain its average peeling strength after repeated open and close operations (i.e., adherence). The cured binder can preferably maintain its average initial peel strength in the range of from about 108 to about 309 N / m (from about 280 to about 800 gpli) for at least five repeated peeling / re-sealing cycles. The adhesion retention value during peeling / re-sealing / peeling may preferably be from about 30 to about 200% of the initial value. When the binding agent is contaminated with crackers, the adhesion retention value may be from about 30% to about 150% of the initial value, and the cracker contamination test method described herein was used.

In another approach, at least a portion of sheet 12 and, in some cases, the outer layer in contact with the bonding agent may include a polymer coating, a layer, a filler, and / or a sealant layer to enhance interfacial bonding between the bonding agent and the packaging substrate of sheet 12. In one The polymer coating form can be selected from ethylene vinyl acetate (EVA), a polyolefin (such as polyethylene), or mixtures thereof. If a polymer layer is used, it may include particles of a cohesive filler. In one form, the filler may be micro- or nanoscale fillers of clay, calcium carbonate, montmorillonite, microcrystalline silica, dolomite, talc, mica, oxides (silicon oxides, aluminum oxides, titanium oxides, etc.) and other additives and / or combinations thereof, added to the polymer coating, the first and / or second panel 14, 16, a sealant layer on this basis or the surface (s) layer (s) of the packaging substrate from sheet 12, or at least on them to enhance binding of the binder clasp agent with sheet 12.

In particular, organoclay filler can be used, and in one aspect, the organoclay filler is montmorillonite modified with organic compounds. An organoclay is a natural clay modified with organic compounds, such as montmorillonite clay, treated or impregnated with surfactants, such as quaternary ammonium salts. Montmorillonite belongs to the phyllosilicate group of minerals, which, as a rule, contain hydrated hydroxide, silicate of sodium, calcium, aluminum, and magnesium. Without striving to be limited by any theory, it is believed that a substrate with an organoclay filler may be able to facilitate the production of effective and resealable fasteners based on a bonding agent, since the filler promotes the formation of a strong bond between the low-adhesive bonding agent and the packaging substrate, so that the bonding agent does not detaches from the packaging substrate from sheet 12 when the packaging 10, 50 is opened.

Effectively dispersing clay or other filler in polyethylene and EVA, which can be used for the sealant layer or other coating of the packaging substrate of sheet 12, can be difficult due to incompatibility of clay-containing fillers and certain polymers. Thus, the introduction of filler using a filler composition comprising a filler mixed with a compatible carrier helps to mix and disperse the filler in the sealant layer. In one approach, a clay-containing filler may be incorporated in a linear low density polyethylene grafted maleic anhydride (MA-LLDPE) carrier which is used in a coating or applied to a substrate. Without striving to be limited by any theory, it is believed that the sections of maleic anhydride in the carrier have an affinity for the clay-containing filler, and the sections of polyethylene in the carrier mix well with other sealant layer polymers. An example of clay-containing filler compositions is available from PolyOne Corporation (Avon Lake, Ohio). Without striving to be limited by any theory, it is believed that particles of clay modified with organic compounds, which can be highly polar, and / or a linear density polyethylene carrier grafted with maleic anhydride (MA-LLDPE) present with clay-containing fillers contribute to the improvement adhesion of the cured coating of the binding agent to the surface of the substrate, increasing the surface energy of the substrate layer.

In addition, it is also believed that at the microscopic level, clay or other filler additive (s) can roughen the surface of the substrate, which positively affects the friction coefficient of the substrate and increases the available contact area between the substrate and the coating, thus providing more centers for manifestations of chemical and / or mechanical binding. In one approach, it is estimated that from about 0.5% to about 20% weight. from the filler composition in the sealant layer has a beneficial effect on the bond strength of the bonding agent with the packaging substrate from sheet 12, so that the bond with the substrate is stronger than the peeling strength between the adhesion portions, so that the engaged sealing zones 28, 30, 52, 54 do not detach when opened . In addition, the filler can roughen the surface of the substrate, allowing it to glide freely on the metal surfaces of the packaging equipment without binding, thus allowing to reduce or eliminate migratory additives that improve the slip in the polymer coating or layer.

In some cases, an optional component of the polymer layer on the substrate of sheet 12 may include a migratory slip improver that helps reduce the coefficient of friction between the substrate and other surfaces, allowing the substrate to slide freely on metal surfaces or on itself. In one aspect, a slip improving erucamide supplement (i.e., unsaturated fatty primary amide) can be used. Slip improvers were used in an amount of 2000 ppm to 7000 ppm; however, it has been found that at such high levels, it is difficult for the binding agent to bond with the low energy surface of the substrate, since the slip improver blocks the surface centers at which adhesion can occur. However, the addition of filler allows the use of a significantly lower level of glidant additives, such as less than about 1000 ppm. In other cases, the substrate contains less than about 700 ppm slip improver, or in other cases, the slip improver is absent. Since the use of a filler reduces the coefficient of friction between the substrate and other surfaces, the effect was previously provided by the addition of a migrating additive that improves gliding, this reduces the concentration of a migrating additive that improves gliding, or eliminates its use. A level of a migratory slip improver that is lower than that commonly used can also enhance the bonding of the cured coating to the substrate both initially and over time, since the additive is less likely to interfere with the bonding of the coating to the substrate. Without striving to be limited by any theory, it is believed that fatty acid amides in a glidant additive, which are low molecular weight components, can migrate or plaque on the surface of the polymer layer, affecting the strength of the bond between sheet 12 and the bonding agent. At the same time, corona treatment or open flame treatment can initially burn all fatty acid amides on the surface of the polymer layer, which leads to a high initial bond strength of the binding agent. Over time, additional fatty acid amides can migrate or plaque on the surface of the polymer layer, which leads to a decrease in bond strength over a long shelf life.

In addition, before applying the bonding layer to the packaging substrate, in some cases, the substrate may be surface pretreated to increase surface energy and / or a primer layer may be applied. For example, possible surface treatment methods may include corona treatment, plasma treatment, open flame treatment, and the like, or chemical coatings such as primers or adhesion enhancers may be used. Corona treatment can increase the surface energy of the substrate, which improves the ability of the coating to bind and remain bound to the substrate. Corona pretreatment may include a cloud of ions that oxidize the surface and make the surface susceptible to coating. Corona pretreatment essentially oxidizes reactive sites on polymer substrates. In corona treatment, ideally, the surface energy after treatment should be approximately 40 dyne or higher.

Without striving to be limited by any theory, it is believed that in some cases, treating the surface of the substrate with a corona discharge helps to ensure a strong bond between the coating layer and the surface of the substrate by increasing the surface energy of the surface of the substrate. In addition to corona treatment, a combination of a low concentration pretreatment enhancing the slip additive and introducing the filler composition into the substrate together result in a strong bond between the resealable fastener and the substrate.

It has been found that in order to achieve balanced peeling, tack and bond with the packaging substrate, as described herein, the amounts of the three components of the binding agent must have a specific proportion of the binding component (i.e., ACR) of the acrylate oligomer with respect to the elastomeric and adhesive components . The ACR for the binding agent is preferably equal to:

In another approach, the ACR may be from about 0.8 to about 1.5.

It was found that the ACR range for the three components in the composition provides a unique binder composition, which has the property of low adhesion to dissimilar substances (i.e. machine components, crumbs, microparticles, food pieces, etc.), however, it can attach itself to itself with sufficient peeling strength to maintain adhesion between them, as well as resistance to contamination. The bonding agent with this particular ACR also provides a re-sealing function that does not cause a significant reduction or does not result in loss of its adhesion / peeling / re-sealing characteristics when it is subjected to repeated opening and closing operations. An ACR of less than about 0.5 is essentially undesirable since curing such a binding agent will require significantly greater amounts of UV radiation energy. If the ACR exceeds about 1.5, the bonding agent will quickly cure, but will have low (or zero) peeling strength, which is unacceptable for a fastener based on a bonding agent described herein. In addition to the desired ACR range, a satisfactory binder composition may in some cases also have other specific parameters, such as the stability of the mixture of components, a certain viscosity of the composition, a certain cure rate, and / or a certain peeling strength.

It is important not only the desired ACR of the components of the binding agent, but the components of the binding agent must also be compatible with each other so that they form a stable fluid mixture. In this context, a binding agent is considered stable if it (at least two or three main components) remains a homogeneous liquid, i.e. no apparent phase separation of the components and gelation during storage at room temperature (approximately 21-24 ° C (approximately 70-75 ° F)) up to three days is not observed.

In addition, the composition of the binding agent may have a viscosity in the range of from about 10,000 to about 50,000 centipoise (cP) or less at room temperature or about 2000 cP or less at about 160 ° F (71 ° C), and in some cases, about 200 cP or less at 160 ° F (71 ° C). This viscosity range involves applying a binder to a carrier film using conventional printing, rolling a roll, or applying techniques using a splined head.

In order to provide a sufficiently cured adhesive layer on the substrate, the bonding agent can be cured using UV sources capable of transmitting energy in the range of from about 100 mJ / cm ² to about 800 mJ / cm ² . This in turn helps to ensure that the bonding agent is sufficiently cured, which is determined by the test value of the abrasion resistance of the IEC (ASTM D5402-06) from approximately 100 double passes or more (described in more detail later in this document).

In one alternative approach, the first peeling strength between the engaged end bands of the bonding agent 32 is less than the first peeling strength between the engaged side bands of the bonding agent 34. For example, the first peeling strength between the end bands of the bonding agent 32 may be from about 39 N / m to 77 N / m (approximately 100 gpli and 200 gpli); and the first peeling strength between the side bands of the bonding agent 34 may be from about 116 N / m to about 348 N / m (about 300 gpli and about 900 gpli). In other words, the peeling strength between the engaged side bands 34 of the bonding agent can be from about 3 times to about 9 times the peeling strength between the hooked end bands 32 of the bonding agent.

In an alternative approach, through the use of a low-adhesive binding agent, for example, having the composition described above, the first and second adhesion zones can have a wider range than described above, or can cover most or all of the first and second parts of the package 14, 16. Low-adhesive properties can to allow the use of sheet 12 as a work surface anyway, since the bonding agent will not substantially adhere to the contents of the package 10, 50. For example, a complete coating of sheet 12 may allow be adapted to consumers size sheet 12, and hence the resulting package. This can provide additional longevity to the perishable contents of the package by better matching the contents and reducing free space around the contents.

Low grip can also be advantageously used to store packaging in a continuous roll 100 of sheets 12, as shown in FIG. 3 and 8. Since the low-adhesive bonding agent does not substantially adhere to other surfaces, it generally does not adhere to the outer surfaces of adjacent sheets 12 in the roll 100, so that successive unfolding and separation of the sheets 12 will not require overcoming the binding force as necessary characteristic of normal binding agents. In one approach, the individual sheets 12 can be separated by a mark or perforated contour 102, applied mechanically or laser. This allows the user to optionally separate the sheet 12 from the roll 100, similar to the operation of a roll of paper towels. In addition, the use of a sheet roll 100 as a storage system advantageously reduces the need for packaging materials, i.e. Holds more packages in a smaller area and allows you to pack the roll in shrink film or in-line packaging instead of a cardboard box. Alternatively, the sheets 12 can be individually wound onto the roll 100 as separate sheets, the user simply unwinding it to separate the pre-cut sheet. In another approach, sheets 12 can be stacked or stacked together in a dispenser, where the user can peel, pull, or otherwise separate sheet 12 for use.

In an approach involving coating most or all of the first and second parts of the package 14, 16, the sheets 12 can be supplied in the form of a continuous roll, which will allow the user to cut the sheet of the desired size. Thus, the sheets 12 can have functionality similar to a plastic film, except for the tendency of the plastic film to bend over and adhere.

In an alternative approach, sheets 12 can be stored on roll 100 in a second, folded configuration. In this approach, the sheets 12 are pre-folded and the adhesion zones 28, 30 are hermetically connected to each other, while they are detachably attached to adjacent sheets 12. Thus, the user can pull and detach the sheet 12 from the roll 100. Then, the user could pull the first and second parts 14, 16 essentially from each other to open the package, insert the desired contents and re-seal the package 10.

EXAMPLES

Example 1

Various mixtures of acrylic oligomers that regulate the stickiness of products and elastomeric materials were tested for compatibility and storage stability (stable was called a mixture in which gel formation does not occur or visible separation after storage for 3 days at room temperature). Table 1 below shows the combinations tested and used in the content.

Components are identified as follows:

A = acrylated epoxidized soybean oil (CN 111 US, Sartomer Company, Exton, PA).

B = methacrylated polybutadiene (Ricacryl® 3500, Sartomer Company).

C = Aliphatic Acrylate Oligomer, High Tack (CN 3001, Sartomer Company). This component contains a mixture of aliphatic urethane acrylate and tackifying hydrocarbon resins.

D = copolymer of polybutadiene and styrene (Ricon 184, Sartomer Company).

E = high-sticky aliphatic urethane oligomer oligomer (CN 3211, Sartomer Company).

F = tackifying concentrate obtained from a light colored aromatic resin with a mild odor (PRO 11236, Sartomer Company).

The stability or compatibility of these components of the binding agent may be a factor for the production, transportation, in-plant storage and use of a liquid coating mixture. Stability was evaluated visually by the appearance and consistency of the observed composition after storage for 3 days (approximately 72 hours). It was found that samples 1,2 and 5 in table 1 provided visually satisfactory mixtures of various components of the binding agent, which remained homogeneous after 3 days, i.e. no separation of the components or gelation was observed. Although sample 2 provided a stable composition, this binder component had an undesirable ACR value and poorly cured (shown in the IEC abrasion test results in table 3 below for sample 10 with a similar composition). However, samples 1 and 5 provided stable binder mixtures that were well cured and also had the desired ACR in the range of 0.5 to 1.5. Other mixtures of samples either separated, or became too viscous and / or formed gels (i.e., sample 8 became gel-like after 3 days). Sample 8 formed a gel, which indicates that the composition formed by the aliphatic acrylate or component E, together with the tackifying component F, was incompatible.

Therefore, in order to obtain a stable binding agent that is suitable for the application described herein, a stable binding agent must essentially satisfy one of the following and, in some cases, more than one of the following, and in other cases, all of the following conditions: compatible components, curable, desired ACR value, all three components are present (i.e. acrylic oligomer, elastomer and tackifier).

Example 2

Based on the data on the initial compatibility of the binding agents for the stable formulations of Example 1, these formulations were further improved to produce five adhesive coating formulations, all of which were stable for at least 24 hours as a mixture of the components shown in Table 2.

Components A-F are indicated above in Example 1. Samples 9 and 10 correspond to samples 1 and 2 of Example 1, respectively. Sample 11 is a variant of sample 5 of example 1. The remaining sample compositions were new.

After the five binding agent compositions showed good compatibility for at least one day, all five samples were mixed with approximately 1% photoinitiator (Esacure® KTO 46, Lamberti Spa, Italy) and then further tested. The photoinitiator was formed from a liquid mixture of trimethylbenzoyl diphenylphosphine oxide, α-hydroxyketones and benzophenone derivatives. Samples were then applied to carrier films containing a copolymer of ethylene vinyl acetate (EVA), a metallocene linear low density polyethylene (LLDPE) and about 12 percent of an organoclay composition (approximately 57-63% organic clay modified clay and a linear density polyethylene carrier grafted with maleic anhydride , PolyOne Corporation, McHenry, Illinois). In particular, the substrate contained approximately 77% by weight. EVA, approximately 10% weight. metallocene LLDPE and approximately 13% weight. organoclay compositions. Then, the samples were cured after being applied to the carrier films, and curing was carried out using UV radiation in three passes under a D-lamp, which is a mercury metal halide lamp. One pass under the D-lamp was approximately equivalent from 75 mJ / cm ² to 100 mJ / cm ² . After curing the coating, the cured adhesive layer was evaluated for the degree of cure and the bonding efficiency of the film.

The degree of cure of the binder was tested using a solvent abrasion test, which is referred to as methyl ethyl ketone abrasion test (IEC), in accordance with ASTM D5204. Good cure results show an abrasion resistance value in the IEC of 100 double passes or more, indicating that the bonding agent is well cured and thus exhibits abrasion resistance in the IEC. Poorly cured binding agents did not show significant resistance to IEC (for example, 10 double passes or less). The results of the abrasion test in IEC are shown in table 3 below.

The stickiness and initial peeling strength were also determined and indicated subjectively. The adhesiveness of the adhesion layer was determined by touch and the adhesiveness was evaluated on a scale of low (L), medium (M) and high (H). Similarly, the subjective power required to peel samples manually was also evaluated on a scale of L, M, and N. The results of these tests are shown in Table 3.

All samples had at least medium tack and peeling strength. Sample 10 showed the highest subjective stickiness and peeling strength, but the worst cure according to the abrasion test in the IEC is approximately 10, which showed that after approximately 10 passes of the IEC, the binding agent was removed from the substrate. Samples 12 and 13 showed turbidity when performing an abrasion test in IEC, most likely due to the fact that component D, a copolymer of styrene and polybutadiene, rose to the surface during abrasion in the IEC. Therefore, although samples 12 and 13 fall into the desired range of the proportion of binding agent, component D is apparently incompatible with the other two components and, therefore, is not a satisfactory binding compound. It was desirable to detect a binding agent with a medium or low subjective level of stickiness, medium or high subjective peeling force and the result of the abrasion test in the IEC from 100 double passes and above without the formation of turbidity, which was shown to a minimum extent by samples 9 and 11.

Example 3

The curing efficiency of three different binding agent compositions was tested by applying the binding agent to the same carrier film as described in Example 2, followed by curing in three different ways; through the stage of UV curing ("UV curing"), performed on industrial equipment, the stage of electron beam (EL) curing ("EL curing"), performed on a similar industrial system, like UV curing, but using electron beam technology, and through EL curing performed on laboratory equipment ("EL lab. curing"). Table 4 below shows the compositions of the three tested binding agents. Both the industrial EL system and the laboratory EL system are involved in the comparison due to the different energy levels provided by each of them. The acrylic oligomer is CN 111 US, the elastomer is Ricacryl® 3500, and the tackifying component is CN3001, as described in Example 1.

"UV curing" included passing the coated sample under the UV lamp at a speed of approximately 7.6 m / min (approximately 25 ft / min) in air and conducting from about 2 to 4 passes so that the sample passed under the entire length of the UV lamps 2 to 4 times. The energy provided by a single pass under a UV lamp at 7.6 m / min (25 ft / min) was equivalent to approximately 100 mJ / cm ² . "UV curing" on an industrial system (Faustel Corporation, Germantown, Wyoming) was performed in a nitrogen atmosphere at a speed of from about 38.1 m / min to about 76 m / min (from about 125 ft / min to about 250 ft / min) with a single pass and at from about 2 Mrad to about 2.4 Mrad, and “UV lab. "curing" was also performed in a nitrogen atmosphere with a requirement of about 6 to 8 passes under a laboratory EL system, which was operated at a speed of approximately 3 m / min (approximately 10 ft / min). The total accumulated dose for 6-8 passes through the laboratory EL block ranged from approximately 2 Mrad to approximately 4 Mrad. It should be understood that in some cases, the smooth surface nature of the fastener-based fastener is desirable for good peeling strength of the binding agent with the binding agent. If the surface of the bonding agent has tubercles, for example it has the consistency of an orange peel, fasteners based on the bonding agent are generally poorly attached to each other. It was noted that all samples of cured coatings had a relatively smooth and even surface. After all samples were cured, the peeling strength was tested in accordance with ASTM Method D3330 / D3330M-04, Method F, these results are shown in Table 5 below.

Surprisingly, UV curing (UV curing) was found to be superior in efficiency to both EL curing. EL curing performed on an industrial line did not adhere at all, i.e. peeling strength 0 N / m (0 gpli). EL lab. curing had some adhesion, but UV cured samples generally had the best adhesion.

Regarding the results of UV curing, samples 15 and 16 had acceptable peel strength ranges (i.e. 185 N / m and 263 N / m (480 gpli and 680 gpli), respectively), while sample 14 had lower tensile strength flaking (i.e. 77 N / m (200 gpli)). The lower peeling strength observed in sample 14 is likely due to the composition of the binding agent used in sample 14, which did not fall within the desired range of 0.5 to 1.5 (i.e., its ACR was 2.2) .

Without striving to be limited by any theory, it is believed that curing by UV radiation in atmospheric air (approximately 21% oxygen) provides curing from the bottom of the sample up to its surface due to the fact that oxygen prevents curing by free radicals in the adhesion sites adjacent with a surface or close to it. Adhesive components have a more aliphatic nature and, consequently, lower surface energy than, for example, components containing an ester or urethane. In some cases, chemical systems self-organize into the lowest possible energy state, if you give them enough time. In the present case, it is believed that the slower curing rate in the UV method provides enough time for the adhesive components of the coating to migrate to the surface. In comparison, the EL curing method leads to a much higher curing reaction rate, thus providing a more random polymer structure in which cross-linking in the growing polymer chain is formed too quickly for significant development of surface-triggered self-ordering. Thus, EL curing can have the opposite curing scenario compared to the UV method, in which EL curing usually takes place in an atmosphere filled with compressed nitrogen and can occur faster on the surface and slower near the substrate. This can lead to completely different binding agent behavior solely on the basis of various curing methods. In a typical situation, such a quick cure would be desirable, however, when curing the coating described herein, such a quick cure is a drawback, since this method does not provide enough time to completely organize the components of the binding agent.

Without striving to be limited by any theory, it is further believed that the slower UV curing time allows growing polymer units to be ordered, so that the polar polymer units prefer the substrate, and non-polar units prefer the surface, while the presence of non-polar units near the substrate surface allows the coating from a binding agent to bind and adhere to itself. This allows the components of the binder agent that are most compatible with the carrier film to accumulate at the interface of the substrate / binder, thereby enhancing adhesion to the substrate, which may be one of the factors helping to avoid detachment from the carrier film.

Example 4

Two inventive, resealable fasteners based on a binding agent, samples 17 and 18, were prepared as shown in Table 6. Two samples of binding agents were compared to a standard fastener based on a pressure sensitive adhesive (PSA control, sample 19), obtained from Nabisco Chips Ahoy Snack'n Seal® industrial packaging using a standard PSA (Fasson 5700, Avery Dennison Corp., Pasadena, CA).

The coated substrate contained approximately 77.2% EVA, approximately 10% metallocene LLDPE, and approximately 12.8% PolyOne 231-615 organoclay filler composition, masterbatch. The masterbatch contains from about 57% to about 63% organic clay modified clay and a carrier containing MA-LLDPE and polyethylene. Sample 17 was cured in a UV curing system having an average light energy of approximately 730 mJ / cm and an average line speed of approximately 30 m / min (approximately 100 ft / min) at an average temperature of thermostat 54 ° C (130 ° F). Sample 18 was cured in a UV curing system having a light energy of approximately 700 mJ / cm ² at a line speed of approximately 30 m / min (approximately 100 ft / min) at a thermostat temperature of 71 ° C (160 ° F). The standard binding agent, PSA control, was already obtained in the final form attached to the cookie packaging (Kraft Foods).

A crumb contamination test was performed on all three packages to find out if food particles would adversely affect the sealing of the corresponding binding agent. The crumb test procedure consisted of the following steps: First, Triscuit® crackers were purchased and crushed using the bottom of a glass vessel. As a result of breaking the crackers, small particles were thus formed, comparable to those that could be found at the bottom of the packet. Then an annular contacting device with a diameter of 5 centimeters (2 inches) was placed on the binding agent of the sample for testing. About 5 grams of crumbs were placed in a ring on a sample. The sample and the ring were shaken slightly from side to side so that the crumbs settled on the surface of the binding agent of the resealable fastener. The ring was removed from the sample and the crumbs were gently shaken off the sample and removed. The ring was again placed on the substrate in its original position and the area open to the crumbs was visually evaluated for the number of crumbs held. A visual rating scale was used from zero to 100, where zero meant no visible retained crumbs, and 100 meant that the entire surface was covered with glued crumbs. The test results of cracker crumbs are shown in table 7.

In addition, the peeling strength of binding agents after contamination with cracker crumbs was tested. Peeling strength was measured using a standard test procedure, ASTM D3330 / D3330M-04, method F, in which bond strength was checked by peeling one side of the other and measuring the desired peeling strength. The initial peeling strength, the subsequent peeling strength after the initial contamination with cracker crumbs, and the second peeling strength after the second round of contamination with cracker crumbs, in which the sample was contaminated by the same procedure as in the initial contamination, were measured. The results for the samples are presented in table 7.

As can be seen from the results, the adhesion ability (i.e., peeling strength) of the PSA control, according to the measurement results in accordance with method ASTM D3330 / D3330M-04, method F, dropped to about 5% of the initial value of the peeling force (t ie from about 193 N / m to about 9.7 N / m (from about 500 gpli to about 25 gpli)) after only two exposure to cracker crumbs. In comparison, both samples based on binding agent 17 and 18 retained at least approximately 41% of the initial value of the peeling force after two exposure to cracker crumbs, and sample 18 actually showed an increase in the peeling force after contamination and after repeated closures and openings. In addition, visual estimates of crumb contamination for samples based on a binding agent ranged from 0 to 10 compared with values from 60 to 80 for the PSA control.

On uncontaminated samples 17, 18 and 19, a rolling ball adhesive test was also performed, which is a modified version of ASTM D3121 and meets the parameters of the ASTM D3121 test method, unless otherwise indicated. The modified test measured how strongly the surface of the coating adheres to dissimilar materials, such as the polar surface of a rolling glass ball.

The rolling ball method included: releasing a glass ball placed 5 centimeters (two inches) upward on a standard inclined surface installed in the ASTM method, after which the ball accelerates down the inclined surface and rolls along the horizontal surface of the sample adhering when the bonding agent is pressed. A modified version of the test included the use of a glass ball instead of a metal ball, the glass ball having a diameter of approximately 0.318 centimeters (approximately 1/8 inch) and the use of a shortened discharge point on an inclined surface (i.e., as indicated above, 5 centimeters (two inches ) uphill). Relative tack was determined by measuring the distance the ball moved along the bonding agent to a stop, starting from the end of the ramp. A longer travel distance of the rolling ball indicates a lower stickiness to the polar surface of the glass ball and indicates that the coating has a lower tendency to adhere to the rollers and metal surfaces of the packaging equipment compared to coatings with a shorter travel distance of the rolling ball, which indicated higher stickiness. A longer travel distance of the rolling ball may also correlate with a lower tendency to stick to food crumbs. In this measurement, the result was limited to a maximum of 10 centimeters (4 inches) since the maximum size of the samples available for testing was 10.2 centimeters × 10.2 centimeters (4.0 inches × 4.0 inches). The results of the stickiness test with a rolling ball are shown in table 8.

As shown in the results, two inventive samples, 17 and 18, had lower surface tack than the control sample, as evidenced by the fact that the glass ball rolled easily over the surface of the resealable fastener and rolled off after 10 centimeters (4 inches) ) the length of the sample. On the other hand, the glass ball adhered to the PSA control almost immediately after contact with the surface of the PSA control, indicating a high stickiness of the coating surface.

Example 5

The re-peeling test was carried out to test the ability to re-seal and peel for many repetitions. Received approximately twenty samples; samples 20-35 were obtained using the composition of the binding agent from sample 17, example 4, and samples 36-38 were obtained using the composition of the binding agent from sample 18, example 4. Samples were obtained on an industrial pilot coating line by flexographic coating method. The liquid binder coating system was preheated to 160 ° F (71 ° C) and circulated through a doctor blade, which was mounted on an engraved chromium oxide ceramic roll. An engraved roll (which was also thermostated at 160 ° F (71 ° C)) transferred the liquid coating from the bonding agent to the structured rubber roll. The structured rubber roll in turn transferred the structured coating onto a moving carrier film (the method shown in FIG. 6). After exiting the coating system, the film passed through an 18.3 m (60 ft) section of thermostat. A device for UV treatment, consisting of 3 rows of UV lamps, was placed at the outlet of the thermostat. The configuration of the line with the UV zone at the exit of the thermostat ensured the maximum path length from the coating system where the material was applied to the UV curing system, which maximized the amount of time available for the liquid coating to flow from the bonding agent and aligned before crosslinking into a crosslinked polymer network. It is believed that in some cases, a smooth and even coating surface helps to achieve the desired peeling force of the bonding agent from the bonding agent for a fully cured bonding agent.

Conducted a series of experimental coating operations. Changed line speed, thermostat temperature and the number of rows of UV lamps. The experimental design and experimental observations are summarized in table 9 below. The apparent surface roughness, the resistance to IEC, and the separation of the binding agent along the link of the binding agent to the binding agent for the sample were determined before testing. In general, samples formed at line speeds from 91.4 m / min to 152.4 m / min (300 ft / min to 500 ft / min) had a visible rough surface and low or subjectively absent peeling force. Instrumental measurement of the peeling force for these samples was for the most part impossible, since the joined samples were separated by themselves, leaving no room for additional tests. Samples formed at 30.5 m / min (100 ft / min) had a visible rough surface and an average peeling force of the bonding agent from the bonding agent. These samples were further characterized using instrumental testing of the peeling force, the data of which are shown in tables 10 and 11 below. In the re-peeling / re-sealing tests, only samples were used that were not separated by themselves, as shown in Table 9. These were samples 21, 22, 29, 30, 31, 32, 35, 36, and 38.

The first series of peeling tests was performed using short peeling intervals, i.e. approximately three minutes between peeling / re-sealing cycles. The results of this test are included in table 10, which shows the average values for two tested samples prepared under the same conditions. These results are compared with sample 19, PSA control, example 4.

The second series of peeling tests was performed using intervals of longer duration between peeling, i.e. approximately 24 hours between peeling / re-sealing cycles in order to understand the effect of a longer contact time of the binder with the binder, the first peeling being carried out approximately one week after sample preparation. The results of the test for peeling / re-sealing with an extended interval are shown in table 11.

The results show that the samples, including the composition of the binding agent of sample 17, Example 4, do not show such a pronounced decrease in the peeling force, which usually occurs with repeated peeling if the interval between peeling is 24 hours (i.e., samples 21, 22 , 29, 30, 31, 32 and 35 in this example). When sample 17 of the binding agent was allowed to remain in contact with itself for approximately 24 hours between peeling, the binding agent restored to approximately 85% of the initial value of the peeling force even after five cycles of peeling / re-sealing. Sample 30 had significantly lower average peeling forces compared to other test samples. Although the combined samples were not separated by themselves, they had insufficient surface smoothness due to the higher line speed of 91 m / min (300 ft / min).

Moreover, it was unexpectedly found that the samples, including the binding agent compositions of sample 18, example 4, actually increased the value of the peeling force (i.e., sample 36 in this example) with repeated peeling both at short and long intervals between cycles peeling test, similar to its results in the peeling test after contamination in table 7, which indicate a complete restoration of the peeling force after re-sealing. An increase in the peeling force was observed only for sample 36. Sample 36 was a sample cured using a slow line speed, which could help to ensure a smooth and even surface of the sample (see table 9). Sample 38 was obtained at a higher line speed than sample 36, resulting in a rough surface, which could lead to a decrease in the value of the peeling force, as well as to a low initial value of the peeling force.

For comparison, the PSA control showed the recovery property only when the interval between exfoliation was long, i.e. was 24 hours. With a short time interval, the peeling force for the control sample actually fell by about 40%.

On the whole, for both peeling / re-sealing tests, samples 22, 32, 35, and 36 showed the best results. All four of these samples correlate with binding agents obtained under similar processing conditions. For example, all four samples are characterized by low line speeds at 30 m / min (100 ft / min) and at least two or more included rows of UV lamps. Binders that failed peel / re-seal tests probably did not have enough time to spread and level before UV curing.

Example 6

An aging study was carried out using binding agent samples 17 and 18, Example 4 in Table 6, to understand the effect of the long contact time of the binding agent with the binding agent on the peeling characteristics. Various properties of the binding agent were tested over a seven-week period, including the subjective initial peeling force (i.e. low, medium, high), the appearance after peeling, subjective stickiness or tendency to stick to the fingers (i.e. no, low, medium, high), the strength of the coating (i.e., the abrasion resistance test in the solvent of IEC ASTM D5204) and instrumental peeling (i.e. 5 consecutive peeling repeated for one sample at intervals of approximately 3 minutes using the ASTM D3330 / D method 3330M-04, method F; tested and averaged the results of two samples), all at different contact times of the binding agent with the binding agent. Binding agents were applied to the same carrier films used in Example 2. Table 12 below shows the aging results for sample 17. Table 13 below shows the aging results for sample 18.

It should be noted that the average value of the peeling strength was the average of five repeated peeling for one sample, which were successively carried out at intervals of approximately three minutes. Thus, the first peeling was carried out and the value of peeling strength was recorded, and the sample of the resealable fastener was re-sealed. After three minutes passed, the resealable fastener was again separated and the value of the peeling force was recorded. The method was repeated until five exfoliations were performed.

The subjective exfoliation force, subjective stickiness, and abrasion test results in the IEC were excellent for both samples 17 and 18, regardless of the duration of contact of the binding agent with the binding agent. The values of the peeling force (i.e., the initial and subsequent peeling for one sample) remained stable for sample 17, regardless of the duration of contact of the binding agent with the binding agent in the range from zero days to 7 weeks. Sample 17 showed a much more stable peeling / re-sealing cycle than sample 18. After the initial peeling of sample 17, the loss in bond strength of the binding agent with the bonding agent, represented by a decrease in the peeling force during subsequent peeling, was substantially less than about 10% for each subsequent peeling and was stable regardless of the contact time of the binding agent with the binding agent.

Starting from week 3, visible changes were observed in both samples 17 and 18 (i.e., noticeable white staining and increased turbidity) when the aged samples were peeled off. It is believed that this apparent change is evidence of microscopic surface deformation of the bonding agent caused by forces acting on the surface of the bonding agent during manual or instrumental peeling. Surface deformation did not affect the essential functional characteristics of the bonding agent (i.e., tack or peeling strength). Ultimately, the sample 17 held a little better, its peeling strength either increased with time, i.e. he restored the peeling strength, or essentially retained approximately 10% loss during subsequent peeling. Example 7

Sample 17, example 4 of the inventive, resealable binding agent-based fastener, was compared with three other inventive re-sealing fastener-based fasteners, samples 39-41 having the compositions shown in Table 14.

Component BR 144 is an acrylic oligomer (BR 144, Bomar Specialties Company, Torrington, Connecticut). The CN 2302 component is also an acrylic oligomer (CN 2302, Sartomer Company). All three samples 39-41 have BR 144 acrylic oligomer in their composition, with samples 39 and 40 having two acrylic oligomers, and sample 41 has three acrylic oligomers present in the composition.

Binders were applied to the same carrier films as used in Example 2. Samples 39-41 were cured in a UV curing system having an average line speed of approximately 7.6 m / min (approximately 25 ft / min) and three passes under UV -lamps, amounting to from about 400 mJ / cm ² to about 600 mJ / cm ² .

The coating strength was tested for four binding agents (i.e., the abrasion resistance test in the solvent of IEC ASTM D5204), as well as the initial peeling strength using ASTM method D3330 / D3330M-04, method F. A stickiness test with a rolling a ball, which was a modified version of the ASTM D3121 test, as described in Example 4, except that the size of the sample available for testing was approximately 6.4 centimeters wide and approximately 18 centimeters long (approximately 2.5 inches) and about 7 inches wide). These results are shown in table 15.

Initial peeling strength, i.e. for the initial exfoliation performed in laboratory conditions, increased for new compositions by approximately 30-300% compared with sample 17 having only one component containing an acrylic oligomer. The distance of movement of the rolling ball increased for new compositions by more than 300% compared with sample 17.

As shown in the results, new formulations containing two or more acrylic oligomers have generally improved performance compared to Sample 17 from the rolling ball test and the peeling strength test. All samples had excellent cure rates, as evidenced by the abrasion test in IEC. In particular, all new sample compositions, i.e. samples 39-41 had a lower surface tack than sample 17, and in particular samples 40 and 41 had an even lower surface tack, as evidenced by the fact that the glass ball rolled easily over the surface of the resealable fastener and rolled off after 18 centimeters (7 inches) of sample length.

Example 8

The four inventive binder-based fastener fasteners of Example 7 were tested in various re-peeling tests. Samples were initially separated and opened and the peeling force was measured in grams per linear inch (gpli) using the ASTM D3330 / D3330M-04 test method, method F, then re-sealed for three minutes and peeling was repeated. This method was repeated every three minutes until ten experimental points were obtained. The results are presented below in table 16.

Example 9

A repeat test at 24-hour intervals was performed using the same four inventive samples from Example 7. The samples were initially separated and opened by measuring the required peeling force. Then the samples were re-sealed and left for 24 hours in a controlled environment, i.e. at 72 ° F and 50% relative humidity, until peeling and opening again. These actions were repeated until five experimental points were collected, or within five days. The results are presented below in table 17.

All four samples retained their peeling characteristics during the five-day test period, with none of the samples falling below 154 N / m (400 gpli) on any day of testing. Samples 39 and 41 actually increase the peeling force and restore the original peeling force or increase the peeling force during the test period. Thus, if these samples are left sealed for at least 24 hours, their adhesion is restored or increased.

Example 10

In example 10, similar to example 9, the test was performed using the four samples described in example 7; however, after each peeling, the adhesion region was brought into contact with whole coffee grains, re-sealed, left closed for 24 hours and re-peeled.

After each peeling, whole grains of coffee were placed on the surface of the binder and removed after less than five minutes. The samples were re-sealed, left for 24 hours in a controlled environment, i.e. at 22 ° C (72 ° F) and 50% relative humidity, until peeling and opening again. These actions were repeated until five experimental points were collected, or within five days. The results are presented below in table 18.

Although the data show a slight decrease in peeling strength, the peeling force values still exceeded 77 N / m (200 gpli) after five peeling / contamination cycles with whole coffee grains.

Example 11

A rolling ball stickiness test was carried out as described in Example 4 on a film without a binding agent for comparison with the stickiness values for a slightly adhesive binding agent. The results are presented below in table 18. Rolling No. 3 from sample 1 included a fairly sharp turn shortly after contact with the film.

Those skilled in the art will find that with respect to the above described embodiments, a wide range of modifications, changes and combinations can be made without departing from the spirit and scope of the present invention, and that such modifications, changes and combinations should be considered as being within the scope of the inventive concept. .

Claims (53)

1. A sheet made with the possibility of folding in a resealable package containing: a sheet of flexible material having edges, an inner surface and an outer surface; a folding part located across the sheet, wherein the folding part divides the sheet into first and second panels, which are arranged to fold relative to each other around the folding part; adhesion zones on the inner surface of the sheet along its edges, wherein the adhesion zones have first and second opposite portions of the adhesion zone on the first and second panels, respectively; the first and second sections of the adhesion zone, made with the possibility of engagement with the formation of a sealed package, when the first and second panels of the sheet are folded together around the folding part; and opposite leaky valves on the outer edges of the inner surfaces along each edge of the sealed package between the edges of the sheet and the adhesion zones, the opposite leaky valves on the outer edges are made to grab them and pull them in different directions to separate the first and second sections of the adhesion zone. 2. The sheet according to claim 1, wherein the sheet includes opposite end edges and opposite side edges, and it further comprises complementary connecting components located on the inner surface of the sheet along its end edges, wherein one of the complementary connecting components is located along one of the opposite end edges and the second of the complementary connecting components is located along the other opposite end edge; moreover, the adhesion zones pass between complementary connecting components and a folding part along each of the opposite side edges. 3. The sheet according to claim 2, in which the opposite leaky valves on the outer edges of the inner surfaces of the folded sheet are additionally located between each end edge of the sheet and a corresponding complementary connecting component. 4. The sheet according to claim 2, in which the complementary connecting components are mating strips. 5. The sheet according to claim 4, in which the mating strips are connected together with the use of fasteners of the "lightning" type. 6. The sheet of claim 1, further comprising one or more intermediate adhesion zones extending between the adhesion zones on the inner surface of the sheet along its edges. 7. The sheet according to claim 1, in which the folding part is a fold line. 8. The sheet according to claim 7, in which the fold line is marked with a sign located on the outer surface or on the inner surface. 9. The sheet according to claim 7, in which the fold line is previously applied. 10. The sheet according to claim 1, in which the opposite leaky valves at the outer edges contain the first and second valves and at least part of the first valve is larger than part of the second valve. 11. A sheet made with the possibility of folding in a resealable packaging, and the sheet contains: a sheet of flexible material having edges, an inner surface and an outer surface; a folding part located across the sheet between the edges, and the folding part divides the sheet into first and second flexible panels, which are made with the possibility of folding relative to each other around the folding part; adhesion material located on the inner surface of the sheet along the edges of the first and second flexible panels; moreover, the clutch material is made with the possibility of alignment and engagement as a result of folding together the first and second panels around the folding part; moreover, the adhesion material includes a UV-cured pressure-sensitive adhesive material comprising at least one UV-curable acrylic oligomer, at least one tackifying component and optionally at least one elastomeric material; moreover, the proportion of the binder component (ACR) in the UV-cured pressure-sensitive adhesive, defined by formula (A), in which the weight percent of the UV-cured acrylic oligomer with respect to the sum of the weight percent of the tackifying component and optionally at least one elastomeric material, ranges from about 0.5 to about 1.5:

; moreover, such an ACR value is effective, so that the UV sealant fastener closure has a first peel strength between the engaged adhesive agent of from about 39 newtons per meter (N / m) to about 348 N / m (from about 100 grams per linear inch (gpli) to about 900 gpli) and up to five subsequent peel strengths between the engaged binding agent, from about 30 percent to about 200 percent of the first peel strength; and moreover, the ACR and the packaging walls are effective for the formation of the bond strength of the UV-cured adhesive when pressed by a bonding agent and the inner surface of the sheet exceeding the first peeling strength and subsequent peeling strengths between the bonding agent, so that the first and second panels can be re-separated without peeling the opposite layers adhesion from the inner surface of the sheet. 12. The sheet of claim 11, wherein the sheet is detachably attached to a plurality of sheets in a twisted configuration. 13. The sheet of claim 12, wherein the plurality of sheets are twisted in a folded configuration. 14. The sheet of claim 11, further comprising one or more intermediate adhesion zones passing between a bonding agent located on the inner surface of the sheet along its edges. 15. The sheet according to claim 11, in which the folding part is a fold line. 16. The sheet according to p. 15, in which the fold line is pre-applied. 17. The sheet according to claim 11, wherein: the sheet has side edges and end edges; the folding part is located across the sheet between the side edges; and the clutch material located on the inner surface of the sheet includes side strips of clutch material located along the side edges, and end strips of clutch material located along the end edges of the first and second flexible panels. 18. The sheet according to claim 17, in which strips of adhesion material located along the edges of the first and second flexible panels are spaced from them to provide grip-free areas of binding agent. 19. The sheet according to claim 17, in which the first peeling force between the engaged end strips of the adhesion material is less than the first peeling force between the engaged side strips of the adhesion material. 20. The sheet according to claim 19, in which the first peeling force of the end stripes of the adhesion material is from about 39 N / m to 77 N / m (about 100 gpli and 200 gpli); and the first peeling force of the side bands of adhesion material is from about 116 N / m to about 348 N / m (about 300 gpli and about 900 gpli). 21. The sheet according to claim 17, in which the angular portion of the end and side strips of the clutch material has serrated edges. 22. The sheet according to claim 17, in which the outer parts of at least one of the end and side strips of the clutch material have serrated edges to provide easier opening when the strips of clutch material are engaged. 23. The sheet according to claim 11, in which the clutch material is located across most of the inner surface of the sheet. 24. The sheet according to claim 23, in which the clutch material is located on the entire inner surface of the sheet. 25. A sheet made with the possibility of folding in a resealable package containing: a sheet of flexible material having end edges, side edges, an inner surface and an outer surface; a folding part located across the sheet, wherein the folding part divides the sheet into first and second flexible panels, which are arranged to fold relative to each other around the folding part; complementary connecting components located on the inner surface of the sheet along its end edges, wherein one component is located along one of the opposite end edges, and the complementary component is located along the other end edge; opposite adhesion bands located on the inner surface of the sheet along each of its lateral edges; folding part located across the sheet between the side edges, and the folding part divides the sheet into first and second flexible panels that are capable of folding relative to each other around the folding part so that the complementary connecting components and adhesion bands are aligned and tightly engaged to form a tight inner space and opposite leaky valves on the outer edges of the inner surfaces of the folded sheet, located along each side and the end of the sealed package between the side edges and adhesion strips and between the end edges and the connecting components, the opposite leaky valves on the outer edges are made with the ability to grab them and pull in different directions for separating the first and second parts of the clutch strip to separate the engaged clutch strip along the lateral edges and the engaged connector nye component along the end edges. 26. The sheet according to p. 25, in which the folding part is a fold line. 27. The sheet according to p. 26, in which the fold line is previously applied. 28. The sheet according to p. 25, in which the connecting components are mating strips. 29. The sheet according to p. 28, in which the mating strip are connected with the use of fasteners of the type "lightning". 30. The sheet of claim 25, further comprising one or more intermediate engagement bands extending between at least one of the lateral engagement bands and the connecting components; moreover, one or more intermediate adhesion bands are made with the ability to align when the sheet is folded, to provide the ability to divide the sealed inner space into many sealed inner spaces.

Images