KR20220094703A - Adhesive separating composition capable of reusing pet bottle by easy desorption of adhesion layer, label using the same and reusing method of pet bottle - Google Patents

Abstract

The present invention relates to a composition for adhesive separation which enables recycling of PET bottles by the easy detachment of an adhesive layer, a manufacturing method of a label using the same, and a recycling method of PET bottles using the same. More specifically, the present invention relates to a composition for adhesive separation, which provides a label material and a label structure which enable easy recycling of PET bottles, and thus can protect adhesive strength and ensure ease of recycling without weakening adhesive force by stable removal of a part of a label adhesive layer, a manufacturing method of a label using the same, and a recycling method of PET bottles using the same. In particular, the present invention is to provide a method of recycling PET bottles in which an area of an adhesive separation layer is maintained within a range of the entire PET bottle area and a label area, so that a label can be easily detached during recycling of the PET bottles.

Description

A composition for adhesive separation that enables the recycling of PET bottles due to the easy detachment of the adhesive layer, and a recycling method of labels and PET bottles using the same OF PET BOTTLE}

The present invention relates to a composition for separating adhesives that enable recycling of PET bottles due to easy detachment of an adhesive layer, a label using the same, and a recycling method for plastic bottles, and more particularly, to a label material that enables easy recycling of PET bottles, a label To provide a structure, and thus to a composition for adhesive separation capable of protecting adhesive strength and securing ease of recycling in a state in which adhesive strength is not weakened by stable partial removal of the label adhesive layer, and a method for recycling labels and plastic bottles using the same.

In particular, it is to provide a method for recycling the plastic bottle by maintaining the area of the adhesive separation layer within a certain range of the total area of the PET bottle and the area of the label, so that the label can be easily detached during recycling of the PET bottle.

In general, in order to increase the recyclability of plastic bottles by reducing the application area of the label adhesive, the adhesion of the adhesive side is lowered, the recyclability of the PET bottle is increased by making the label detachable easily, and the material and structure of the packaging label are changed due to the easy label detachment. is needed

As an example, looking at the manufacturing process of label adhesive removal, a transparent silicone solution is partially applied to the adhesive part sealed after the adhesive is completed. Then, when the curing of the application part is carried out in a state in which the transparent silicone solution is applied, the applied transparent silicone solution is cured to form an anti-adhesive layer, thereby preventing the adhesive from being easily detached.

However, since the transparent silicone coating film produced by the above process completely blocks the adhesive performance, there is a problem in that it is difficult to reproduce or restore the label adhesive.

Therefore, there is a need for research and development on labels that are easily detachable after use of PET bottles while maintaining adhesive properties.

Korean Patent Publication No. 10-2020-0120914 Korean Patent Publication No. 10-1636707 Korean Utility Model Publication 20-0273127 Korean Utility Model Publication 20-0396941 Korean Patent Publication No. 10-2069463

The present invention lowers the high adhesive performance of the acrylic emulsion adhesive on the adherend surface with low surface energy, thereby facilitating the separation of the label from the adherend surface. In order to proceed, it is possible to facilitate the separation characteristics of the label by using an adhesive separation layer formed to be less than a certain area of the adhesive surface. An object of the present invention is to provide a composition for adhesive separation that enables recycling of PET bottles due to easy detachment of the adhesive layer as described above, a label using the same, and a recycling method of plastic bottles.

According to an embodiment of the present invention, the adhesive separation composition that enables the recycling of PET bottles due to the easy detachment of the adhesive layer is 30% to 40% by weight of a triacrylate-based compound, 30% to 40% by weight of an aliphatic urethane acrylate compound %, 5 wt% to 10 wt% of amorphous silica, 1 wt% to 5 wt% toluene, 1 wt% to 5 wt% ammonium salt, and 1 wt% to 5 wt% solvent.

The triacrylate-based compound is characterized in that it is represented by the following formula (1).

[Formula 1]

The ammonium salt is one or a mixture of two selected from a trialkylammonium salt and a dialkylmethylammonium salt, and the trialkylammonium salt, the alkyl of the dialkylmethylammonium salt is an alkyl having 1 to 5 carbon atoms, Anion is characterized in that it is halogen or hydroxide.

A label that enables recycling of PET bottles due to easy detachment of the adhesive layer, which is an embodiment of the present invention, includes a release layer (10); an adhesive layer 20 formed on the release layer; a film layer 30 formed on the adhesive layer; a printed layer 40 formed on the film layer; And a protective layer 50 formed on the printed layer; is a label that enables recycling of PET bottles due to easy detachment of the adhesive layer comprising a, and the adhesive separation composition is applied on one side of the adhesive layer facing the release layer. The adhesive separation layer forms a line pattern formed in an oblique direction, and the line pattern includes lines of a predetermined width spaced apart at a predetermined interval, the label is rectangular, and the rectangular shape is formed. If the direction of the lower side is defined as the x-axis and the direction of the upper side of the rectangle is defined as the y-axis, the angle between the long axis direction and the x-axis direction of the line pattern of the applied adhesive separation layer is 40° to 50°, and the The ratio of the area of the label to the area of the adhesive separation layer is 1:0.4 to 0.6, the ratio of the total area of the plastic bottle to the area of the adhesive separation layer is 1:0.1 to 0.3, and the adhesive separation composition is a triacrylate-based compound 30% to 40% by weight, 30% to 40% by weight of an aliphatic urethane acrylate compound, 5% to 10% by weight of amorphous silica, 1% to 5% by weight toluene, 1% to 5% by weight of an ammonium salt, a solvent 1% to 5% by weight.

In the recycling method of a plastic bottle with a label, which is an embodiment of the present invention, when recycling the plastic bottle, one of the four corners of the label is pulled to separate the label from the circular plastic bottle, and the plastic bottle is circular. , In addition, irregularities are formed on the surface of the plastic bottle to which the label is attached, and when a direction parallel to the bottom surface of the plastic bottle is defined as the x-axis, the long axis direction of the line pattern of the applied adhesive separation layer and the plastic bottle The angle between the x-axis direction of the bottom surface of the is 45°.

The present invention has the effect of adjusting the adhesive force by easily peeling the label off when recycling the PET bottle by forming the adhesive separation layer having high adhesive performance on the adherend surface with low surface energy in an oblique direction.

1 is a schematic view showing a labeled PET bottle of the present invention.
2 is a schematic diagram showing a cross-sectional view of the label of the present invention.
3 is a schematic view showing the formation of an adhesive separation layer on the adhesive layer of the present invention.
4 is a photograph of a PET bottle having a label attached thereto according to an embodiment of the present invention.
5 is a view showing a simulation result of the surface area of a PET bottle according to an embodiment of the present invention.
6 and 7 are tables showing measured areas and experimental results according to an embodiment of the present invention.

Hereinafter, the present invention according to an exemplary embodiment will be described in detail with reference to the accompanying drawings for a composition for separating the adhesive that enables recycling of a PET bottle due to the easy detachment of the adhesive layer, a label using the same, and a recycling method of a PET bottle.

In the following drawings, the same reference numerals refer to the same components, and the size of each component in the drawings may be exaggerated for clarity and convenience of description. On the other hand, the embodiments described below are merely exemplary, Various modifications are possible from this embodiment. Hereinafter, what is described as "upper" or "upper" may include not only directly on in contact but also on non-contacting. Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. The singular expression includes the plural expression unless the context clearly dictates otherwise. Also, when a part "includes" a component, it means that other components may be further included, rather than excluding other components, unless otherwise stated. In addition, terms such as “.unit” and “module” described in the specification refer to a unit that processes at least one function or operation.

(Composition for adhesive separation)

The adhesive separation composition of the present invention can adjust the adhesive force by easily separating the label from the PET bottle for recycling of the PET bottle. The composition for separation of the adhesive of the present invention as described above is 30% to 40% by weight of a triacrylate-based compound, 30% to 40% by weight of an aliphatic urethane acrylate compound, 5% to 10% by weight of amorphous silica, and 1% by weight of toluene to 5% by weight, 1% to 5% by weight of an ammonium salt, and 1% to 5% by weight of a solvent.

The triacrylate-based compound may contain 30% to 40% by weight, and may be one or a mixture of two selected from the group consisting of a compound represented by Formula 1 and a compound represented by Formula 2 below.

[Formula 1]

[Formula 2]

The adhesive separation composition of the present invention may further include 1% to 3% by weight of a tetraacrylate-based compound and 1% to 3% by weight of a diacrylate compound.

The tetra acrylate-based compound may preferably be a compound represented by the following formula (3).

[Formula 3]

The diacrylate-based compound may preferably be one or a mixture of two selected from the group consisting of a compound represented by the following formula (4) and a compound represented by formula (5).

[Formula 4]

[Formula 5]

The aliphatic urethane acrylate compound may contain 30% to 40% by weight, and the urethane acrylate is preferably an aliphatic urethane acrylate that does not include a benzene ring in terms of adhesion, curability, hardness, and the like.

The urethane acrylate may have 3 or less functional groups, preferably 1 to 3 functional groups. When the number of functional groups of the aliphatic urethane acrylate exceeds three, the flexibility of the label may be insufficient. The molecular weight of the aliphatic urethane acrylate may preferably be about 800 to about 2,500 g/Mol, and more preferably about 1,000 to about 1,600 g/Mol.

The amorphous silica may include 5 wt% to 10 wt%. Amorphous silica is contained in the adhesive separation composition, and accordingly, the amorphous silica exists in a form integrated with the triacrylate compound, thereby increasing the durability and strength of the label.

The toluene may be included in an amount of 1 wt% to 5 wt% for coating properties.

The solvent may include 1 wt% to 5 wt%. The solvent is preferably an organic solvent having a boiling point of 100°C to 200°C, and preferably a compound represented by the following formula (6) in terms of coatability and dryness.

[Formula 6]

The ammonium salt is one or a mixture of two selected from a trialkylammonium salt and a dialkylmethylammonium salt, and the trialkylammonium salt, the alkyl of the dialkylmethylammonium salt is an alkyl having 1 to 5 carbon atoms, The anion may be halogen or hydroxide.

The adhesive separation composition of the present invention may further include 0.1 wt% to 0.3 wt% of a plasticizer. A plasticizer may be used to make the pressure-sensitive adhesive separation layer flexible, and a compound represented by the following Chemical Formula 7 may be preferably used.

[Formula 7]

(Label that enables recycling of PET bottles due to easy detachment of the adhesive layer)

1 shows a PET bottle with a label of the present invention, and FIG. 2 shows a label that enables recycling of the PET bottle due to the easy detachment of the adhesive layer of the present invention. As shown in Figure 2, the label of the present invention, the release layer (10); an adhesive layer 20 formed on the release layer; a film layer 30 formed on the adhesive layer; a printed layer 40 formed on the film layer; and a protective layer 50 formed on the printed layer.

Here, the label of the present invention may form a pressure-sensitive adhesive separation layer 22 coated with an adhesive separation composition inside the pressure-sensitive adhesive layer 20 facing the release layer 10 . For example, a space for forming the adhesive separation layer 22 may be formed in advance inside the adhesive layer 20 , and may be formed by applying the adhesive separation layer 22 to the space. When using the label, the back layer 10 may be separated and the adhesive layer 20 and the adhesive separation layer 22 may be attached to the adherend to be used.

Alternatively, the label of the present invention may form a pressure-sensitive adhesive separation layer 22 coated with an adhesive separation composition on one side of the pressure-sensitive adhesive layer 20 rather than the inside of the pressure-sensitive adhesive layer 20 facing the release layer 10 . . For example, the adhesive separation layer 22 coated with the adhesive separation composition on one surface of the flat adhesive layer 20 may be formed in an oblique direction. When using the label, the back layer 10 may be separated and the adhesive layer 20 and the adhesive separation layer 22 may be attached to the adherend to be used.

The composition for separation of the adhesive is 30% to 40% by weight of a triacrylate-based compound, 30% to 40% by weight of an aliphatic urethane acrylate compound, 5% to 10% by weight of amorphous silica, 1% to 5% by weight of toluene , 1 wt% to 5 wt% of an ammonium salt, and 1 wt% to 5 wt% of a solvent may be included. In addition, if necessary, 1 wt% to 3 wt% of a tetra acrylate compound, 1 wt% to 3 wt% of a diacrylate compound, and 0.1 wt% to 0.3 wt% of a plasticizer may be further included.

Since the components of the adhesive separation composition are the same as the adhesive separation composition that enables recycling of PET bottles due to the easy detachment of the adhesive layer described above, a detailed description thereof will be omitted.

3 is a schematic view showing the formation of an adhesive separation layer on the adhesive layer of the present invention. As shown in FIG. 3A , the adhesive separation layer 22 forms a line pattern formed in an oblique direction, and the line pattern may be formed in which lines of a predetermined width are spaced apart from each other at predetermined intervals. Here, it is preferable that the ratio of the line width (α) of the line pattern to the interval (β) between the lines is 1:1.5 to 1.8 in order to prevent voids when separating the label from the PET bottle.

On the other hand, if the label and the adhesive layer 20 of the present invention are rectangular in size, the direction of the lower side of the rectangle is defined as the x-axis and the direction of the upper side of the rectangle is defined as the y-axis, the applied adhesive separation layer 22 ), the angle θ between the long axis direction and the x-axis direction of the line pattern of the line pattern preferably has 40° to 50°, more preferably 45°.

The ratio of the area of the label to the area of the adhesive separation layer 22 is preferably 1:0.4 to 0.6, and the aspect ratio of 1:0.4 to 0.5 is easily removable while maintaining adhesiveness when separating the label from the PET bottle. more preferably in

In addition, the ratio of the total area of the PET bottle to the area of the adhesive separation layer is preferably 1:0.1 to 0.3, and 1:0.15 to 0.2 is easily detachable while maintaining the adhesiveness when separating the label from the plastic bottle. more preferably.

As shown in FIG. 3B , the adhesive separation layer 22 forms a line pattern formed in an oblique direction, and also separates the adhesive separation layer 22 in the form of a line surrounding the entirety of the adhesive separation layer 22 . A layer 23 may be further included. The outer adhesive separation layer 23 may use the same component as the adhesive separation layer 22 . By using the outer adhesive separation layer 23, it is possible to prevent a lifting phenomenon at the outer edge of the label. In addition, in the outer adhesive separation layer 23, a non-continuous region 20A may be formed at any one edge of the label. As a part that separates the label when recycling the PET bottle, if it is peeled off from the non-continuous area 20A at any one edge of the label as described above, it has the advantage of being more easily recyclable.

Each layer constituting the label will be described in detail below.

The release layer 10 is formed to protect the film layer, and basically, release property, adhesion, surface smoothness, dimensional stability, etc. are required. In addition, a low peeling force is required because it should be well peeled from the adhesive layer. Therefore, the release layer 10 of the present invention can be used without any limitation as long as it satisfies the above physical properties. For example, it may be formed using paper, laminated paper, plastic film, etc., preferably polyethylene laminated paper may be used.

The adhesive layer 20 can be easily separated from the release layer, is for attaching the film layer 30 to the substrate, and any material that satisfies the above physical properties can be used without any limitation. For example, by mixing 2-ethylhexyl acrylate, n-butyl acrylate, polyethylene, rosin ester, hydrolysis products, acrylic ester, benzenesulfonic acid, etc., it can be used as a stretched or unstretched cast film or inflation film. .

It is preferable to use a film layer having excellent mechanical properties such as tensile strength, rigidity, and surface hardness and optical properties such as gloss and transparency for the film layer 30, and any material satisfying the above physical properties can be used without any limitation. can For example, a film layer may be prepared by using a compatibilizer and a dispersant in a mixture of polypropylene, polybutene, and polyisobutylene.

The printing layer 40 may be printed on the film layer 30 by a printing method, or a printed transparent film layer may be used.

The protective layer 50 is formed by mixing a protective film composition including epoxy acrylate, urethane acrylate, trimethylolpropane, silica, photoinitiator, ammonium salt, solvent, and additives, applying it on the printed layer, and curing it with a UV lamp. can be

(How to recycle PET bottles)

When a label having an adhesive layer is attached to a round plastic bottle and the label is separated for recycling after use of the plastic bottle, it is important to separate the label without leaving traces of the label on the PET bottle. In particular, if the surface of the PET bottle to which the label is attached has irregularities, it is preferable that the line pattern to which the adhesive separation layer is attached has an oblique direction in terms of preventing voids or the like when the label is separated.

That is, if a direction parallel to the bottom surface of the plastic bottle is defined as the x-axis, the angle between the long axis direction of the line pattern of the applied adhesive separation layer and the x-axis direction of the bottom surface of the plastic bottle is 45° can be used

By attaching the label as described above, the label can be easily separated from the round plastic bottle by pulling any one of the four corners of the label when recycling the plastic bottle.

(Example)

39 wt% of a triacrylate-based compound represented by Formula 1, 39 wt% of an aliphatic urethane acrylate compound, 10 wt% of amorphous silica, 4 wt% of toluene, ammonium salt (trialkylammonium salt, carbon number 3, anion is hydroxide) 4 By weight, 4% by weight of the solvent represented by Chemical Formula 6 was mixed to prepare a composition for adhesive separation. In a commercially available label having a release layer, an adhesive layer, a film layer, a printing layer, and a coating layer, the adhesive separation composition is applied in a diagonal direction in the form of a line on the adhesive layer facing the release layer, and the label is placed on the surface of a plastic bottle. was attached.

4 is a photograph of a PET bottle having a label attached thereto according to an embodiment of the present invention.

In relation to the determination of the area and amount of the adhesive separation composition and the adhesive of the label in the plastic bottle, the surface area of the PET bottle (excluding the cap of the plastic bottle, the same shall apply hereinafter) and the application area of the label and the adhesive separation composition are measured by device analysis, and the conversion value of the ratio is calculated saved In addition, for the device measurement for this determination, the area was obtained through 3D area calculation by scanning the corresponding area through a 3D scanner. The test equipment used was Einscan Pro 2X PLUS (manufacturer SHINING 3D).

As for the determination criteria, the area and amount of the pressure-sensitive adhesive separation layer to which the pressure-sensitive adhesive separation composition has been applied was judged as the best recycling if the heat-alkaline pressure-sensitive adhesive separation composition was used, less than 20% of the surface area of the PET bottle and less than 60% of the label area.

As shown in FIG. 5 , as a result of the device analysis, the area of the PET bottle (mm ² ), the label area (mm ² ), and the application area of the adhesive separation composition and the pressure-sensitive adhesive (mm ² ) were simulated.

6 shows the measured area for determination of the area and amount of the pressure-sensitive adhesive release composition and the pressure-sensitive adhesive, and FIG. 7 illustrates the results of determination of the area and amount of the pressure-sensitive adhesive release composition and the pressure-sensitive adhesive.

As shown in FIGS. 6 and 7 , it was confirmed that the label of the present invention has excellent properties in terms of material, structure, and ease of recycling of the packaging material.

The present invention is not limited to the above embodiments, but can be manufactured in a variety of different forms, and those of ordinary skill in the art to which the present invention pertains can take other specific forms without changing the technical spirit or essential features of the present invention. It will be understood that it can be implemented as Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

100 labels
200 PET Bottles
10 release layer
20 adhesive layer
22 adhesive separation layer
30 film layer
40 printed layers
50 protective layer

Claims (5)

30% to 40% by weight of triacrylate compound, 30% to 40% by weight of aliphatic urethane acrylate compound, 5% to 10% by weight of amorphous silica, 1% to 5% by weight of toluene, 1% by weight to ammonium salt 5% by weight, and 1% to 5% by weight of a solvent, the adhesive separation composition that enables the recycling of PET bottles due to the easy detachment of the adhesive layer. The method according to claim 1,
The triacrylate-based compound is an adhesive separation composition that enables recycling of PET bottles due to the easy detachment of the adhesive layer, characterized in that it is represented by the following formula (1).
[Formula 1]

3. The method according to claim 2,
The ammonium salt is one or a mixture of two selected from a trialkylammonium salt and a dialkylmethylammonium salt, and the trialkylammonium salt, the alkyl of the dialkylmethylammonium salt is an alkyl having 1 to 5 carbon atoms, Anions are halogen or hydroxide, characterized in that the adhesive separation composition that enables the recycling of PET bottles due to the easy detachment of the adhesive layer. release layer 10; an adhesive layer 20 formed on the release layer; a film layer 30 formed on the adhesive layer; a printed layer 40 formed on the film layer; and a protective layer 50 formed on the printed layer; is a label that enables recycling of PET bottles due to easy detachment of the adhesive layer comprising:
Forming a pressure-sensitive adhesive separation layer on one side of the pressure-sensitive adhesive layer facing the release layer is coated with a composition for separation adhesion,
The adhesive separation layer forms a line pattern formed in an oblique direction, and in the line pattern, lines of a certain width are spaced apart from each other at regular intervals,
The label is rectangular, and when the direction of the lower side of the rectangle is defined as the x-axis and the direction of the upper side of the rectangle is defined as the y-axis, the angle between the long axis direction and the x-axis direction of the line pattern of the applied adhesive separation layer is 40 ° to 50 °,
The ratio of the area of the label to the area of the adhesive separation layer is 1:0.4 to 0.6,
The ratio of the total area of the plastic bottle and the area of the adhesive separation layer is 1:0.1 to 0.3,
The adhesive separation composition is 30% to 40% by weight of a triacrylate-based compound, 30% to 40% by weight of an aliphatic urethane acrylate compound, 5% to 10% by weight of amorphous silica, 1% to 5% by weight of toluene , A label that enables recycling of PET bottles due to easy detachment of the adhesive layer, characterized in that it contains 1 wt% to 5 wt% of an ammonium salt, and 1 wt% to 5 wt% of a solvent. It is a recycling method of plastic bottles with the label of claim 4,
When recycling the plastic bottle, pull any one of the four corners of the label to separate the label from the plastic bottle,
The plastic bottle has a circular shape, and irregularities are formed on the surface of the plastic bottle to which the label is attached. If the direction parallel to the bottom of the plastic bottle is defined as the x-axis, The plastic bottle recycling method, characterized in that the angle between the long axis direction and the x-axis direction of the bottom surface of the plastic bottle is 45°.

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