JP2024083116A - Label and label peeling method - Google Patents

Abstract

[Problem] To provide a label that can be easily peeled off from a substrate without immersing the container in liquid. [Solution] The label (10) is a label (10) that is adhered to a substrate (1) that is used for recycling or reuse, and includes an adhesive layer (11) that can adhere to the substrate (1), and a printed layer (14) that is laminated on the adhesive layer (11) and includes a heating element (20) that generates heat when irradiated with energy rays (60) at a position corresponding to at least a part of the outer periphery of the adhesive layer (11). [Selected Figure] Figure 1

Description

The present invention relates to a label and a method for peeling the label.

Technologies for separating labels from containers for recycling purposes are known. For example, U.S. Patent No. 5,399,433 discloses a label adapted to be adhered to a beverage bottle, which shrinks at a designated washing temperature from a temperature range between about 50°C and about 95°C. The invention described in U.S. Patent No. 5,399,433 specifies the degree of shrinkage and shrinkage stress of the laminate when shrinking at the designated washing temperature, thereby separating the label from the container even when the adhesion of the label to the container is high.

JP 2012-502305 A

However, when recycling or reusing labeled objects, it may be necessary to remove the label from the container by washing and then dry the object. Also, when a label is attached to a container that should not be immersed in liquid, such as an electronic device, an ink cartridge, or a paper package, it may not be possible to remove the label from the object by washing.

In addition, one technique for separating the label from the container is to use an alkaline liquid, but in that case, a post-treatment process is required to treat the waste liquid. Also, in the above case, the container and label are usually crushed before being separated from each other, so the container cannot be reused.

One aspect of the present invention aims to provide a label that can be easily peeled off from a substrate without immersing the substrate in a liquid, and a method for producing the label.

In order to solve the above problems, a label according to one embodiment of the present invention is a label that is adhered to a substrate to be used for recycling or reuse, and includes an adhesive layer that can adhere to the substrate, and a printed layer that is laminated on the adhesive layer and includes a heating element that generates heat when irradiated with energy rays at a position corresponding to at least a portion of the outer periphery of the adhesive layer.

A label peeling method according to one aspect of the present invention is a label peeling method for peeling a label adhered to an adhesive object from the adhesive object, and includes an irradiation step of irradiating the label with energy rays, and a heating step of causing a heating element included in a printing layer laminated on an adhesive layer that adheres the label to the adhesive object, at a position corresponding to at least a portion of the outer periphery of the adhesive layer, to generate heat by irradiation with the energy rays.

According to one aspect of the present invention, it is possible to provide a label and a method for producing the same that can be easily peeled off from an object to be adhered without immersing the object in a liquid.

1 is a cross-sectional view of a label according to a first embodiment of the present invention. FIG. 2 is a plan view showing an example of the configuration of the label. 4 is a front view showing the label after being irradiated with energy rays. FIG. FIG. 11 is a plan view showing another example of the configuration of the label. 11A and 11B are plan views showing other examples of the shape of the label. 4A to 4C are diagrams illustrating a method for peeling the label from the substrate. FIG. 2 is a diagram showing an example of a peel test device in a test example of the present invention. 1 is a table showing some of the results of the test. 1 is a table showing other results of the test. 13 is a plan view showing the formation pattern of the glue suppression portion of Examples 9 and 10. FIG.

[Embodiment]
An embodiment of the present invention will be described in detail below. However, the following description is merely an example of a label according to the present invention, and the technical scope of the present invention is not limited to the illustrated example.

(Label Overview)
When recycling or reusing a labeled object such as a container, it is often necessary to peel the label that has been attached to the object from the object. When peeling a label from an object, depending on the properties of the object, it may not be possible to use a liquid.

Figure 1 is a cross-sectional view of a label 10 according to a first embodiment of the present invention. As shown in Figure 1, the label 10 has a printed layer 14 that at least partially contains a heating element 20 that generates heat when irradiated with energy rays 60, and can be adhered to an object to be adhered 1 by an adhesive layer 11. The label 10 is made such that the heating element 20 contained in the printed layer 14 is heated by the energy rays 60, thereby making it possible to easily peel the label 10 from the object to be adhered 1 without immersing the object to be adhered 1 in liquid.

(Subject to be adhered)
The substrate 1 is an object to which the label 10 is adhered. The substrate 1 is not particularly limited and may be a beverage container. In addition, since the label 10 can be easily peeled off from the substrate 1 without immersing it in liquid, even if the substrate 1 is an electrical device that is not preferably immersed in liquid, an ink cartridge, or a plastic tank that contains cleaning liquid, the label 10 can be peeled off from the substrate 1 and the substrate 1 can be reused.

(Basic label structure)
The label 10 is a label that is affixed to the substrate 1 for reuse or recycling. Here, reuse refers to reusing the substrate 1. Recycling refers to using the substrate 1 as a material to create a new product.

Figure 2 is a plan view showing an example of the configuration of label 10. 2001 in Figure 2 is a view of label 10 from the front side (the side on which adhesive layer 11 is not formed), and 2002 in Figure 2 is a view of label 10 from the back side (the side on which adhesive layer 11 is formed).

As shown in FIG. 2 2001 and FIG. 2 2002, in this embodiment, the label 10 has a substantially rectangular shape. The label 10 includes an adhesive layer 11 and a label body 12.

(Adhesive layer)
The adhesive layer 11 is a layer that can adhere to the substrate 1, and adheres the label body 12 to the substrate 1. As shown in 2002 in Fig. 2 , the adhesive layer 11 is provided on one surface 12a of the label body 12 at a position that corresponds to the outer periphery of the label body 12 when the label body 12 is viewed in plan, and adheres the label body 12 to the substrate 1.

This allows the outer periphery of the label body 12 to be adhered to the substrate 1. Therefore, when the label 10 is adhered, the outer periphery of the label body 12 does not turn over, and the label body 12 can remain adhered to the substrate 1 while the user is using the substrate 1, for example.

The adhesive layer 11 may be provided over the entire surface of one side 12a of the label body 12, or may be provided only on a portion of the surface.

The adhesive used in the adhesive layer 11 may be any adhesive that can be peeled off after adhesion, and there are no particular limitations on the material, but it is desirable that the adhesive strength at room temperature is 1.0 N/25 mm or more and 20.0 N/25 mm or less. This allows the label 10 to be suitably peeled off from the substrate 1 at the location corresponding to the printed layer 14 containing the heating element 20 when the heating element 20 contained in the printed layer 14 described below generates heat.

Furthermore, if the adhesive strength is too weak, the label 10 may unintentionally peel off from the substrate 1, while if the adhesive strength is too strong, adhesive is likely to remain on the substrate 1 when the label 10 is peeled off from the substrate 1. Furthermore, if the adhesive strength is too strong, it will be difficult for a user to peel the label 10 off the substrate 1. Therefore, it is more desirable for the adhesive strength to be 5.0 N/25 mm or more and 10.0 N/25 mm or less at room temperature.

In addition, the adhesive layer 11 is formed with a glue suppressing portion 30 in an area corresponding to the center of the label body 12 when the label body 12 is viewed in a plan view, which weakens the adhesive strength of the adhesive layer 11 compared to when the adhesive layer 11 is directly adhered to the object 1.

The adhesive suppression portion 30 can be formed, for example, by printing ink on the surface of the adhesive layer 11 opposite the label body 12. The adhesive suppression portion 30 may be formed by printing a colorless transparent ink, or may be formed by printing a colored ink. Note that the adhesive layer 11 may be selectively formed on the label body 12, resulting in a configuration without the adhesive suppression portion 30.

Explaining based on 2002 in FIG. 2, if the adhesive layer 11 is configured without the adhesive suppression portion 30, the adhesive layer 11 must be provided along the outer periphery of the label body 12. In contrast, if the adhesive suppression portion 30 is formed, for example, even if the adhesive suppression portion 30 is formed on a part of the outer periphery, the adhesive exists along the outer periphery of the label body 12, so that the outer periphery of the label body 12 can be adhered to the object 1.

The label 10 may also be provided with a release paper that covers the exposed portion of the adhesive layer 11. This allows the label 10 to be easily distributed even when it is not adhered to the substrate 1.

(Label body)
As shown in Fig. 1, the label body 12 includes a base layer 13, a printing layer 14, and a shrink layer 15. In other words, the label body 12 includes the printing layer 14 in addition to the adhesive layer 11 in the label 10. The label body 12 includes the base layer 13, the printing layer 14, and the shrink layer 15 laminated in this order from the adhesive layer 11 side. The label 10 may be a transfer label used for cosmetics or fake tatoes, in which case the label body 12 includes only the printing layer 14.

(Printing layer)
The printing layer 14 is laminated on the adhesive layer 11 and includes a heating element 20 that generates heat when irradiated with energy rays 60 at a position corresponding to at least a part of the outer periphery of the adhesive layer 11. Here, "laminated on the adhesive layer 11" does not only mean that the printing layer 14 is directly laminated on the adhesive layer 11, but also means that the printing layer 14 is laminated on the adhesive layer 11 with another layer being present between the adhesive layer 11 and the printing layer 14, as shown in this embodiment.

In this embodiment, as shown in 2001 in FIG. 2, the heating element 20 is included in the printed layer 14 located in a region along the outer periphery of the label body 12 when the label body 12 is viewed in a plan view. Specifically, the heating element 20 is included in the printed layer 14 located in a region along the outer periphery of the label body 12 when the label body 12 is viewed in a plan view. Note that in FIG. 2 and FIG. 4 described later, the region in the printed layer 14 that includes the heating element 20 is shown as a heating element-containing portion 141.

The energy rays 60 include, for example, ultraviolet rays, microwaves, and electron beams, and are irradiated, for example, from an irradiation source 50 (see FIG. 6). When the energy rays 60 are ultraviolet rays, it is preferable that the irradiation source 50 is an LED (light-emitting diode) light source.

The heating element 20 may be an ink that generates heat when exposed to energy rays 60, or a material that generates heat when exposed to energy rays 60 may be mixed into the ink. When the energy rays 60 contain ultraviolet rays, the ink used for the heating element 20 may be, for example, black ink or indigo ink, and the material mixed into the ink for the heating element 20 may be an ultraviolet absorbing material. By using a medium mixed with an ultraviolet absorbing material as the heating element 20, the printing layer 14 can be made transparent, improving the design of the label 10.

The printing layer 14 may also be, for example, a varnish mixed with an ultraviolet absorbing material or an anchor coating agent mixed with an ultraviolet absorbing material.

When microwaves are included as the energy rays 60, the ink used as the heating element 20 may be, for example, black ink or silver ink, and the material mixed into the ink as the heating element 20 may be an iron oxide pigment such as red iron oxide, a transparent conductive film, or the like. The frequency of the microwaves used as the energy rays 60 is preferably about 2.45 GHz.

It is preferable that the temperature at which the heating element 20 is heated by the energy rays 60 is approximately 60 degrees or higher and 85 degrees or lower. In addition, in the process of peeling the label 10 from the substrate 1, only the heating element 20 contained in the printing layer 14 of the label 10 is heated by the energy rays 60, so the thermal impact on the substrate 1 can be minimized.

The thickness of the printed layer 14 is not particularly limited, but can be 1 μm or more and 5 μm or less. In addition, in the printed layer 14, in the area other than the heating element-containing portion 141, for example, product-related information may be printed. Product-related information is, for example, the product name, picture, manufacturer name, logo mark, product description, etc.

Furthermore, the heating element 20 may be included in the entire printed layer 14, in which case the printed layer 14 may be formed only partially on the label body 12. For example, as illustrated in 2001 of FIG. 2, the printed layer 14 may be formed only on the heating element-containing portion 141. In that case, the label body 12 may further be laminated with a printed display layer on which product-related information is printed.

(When the label is exposed to energy rays)
3 is a front view showing the state in which the label 10 is irradiated with energy rays 60. When the label 10 is irradiated with the energy rays 60, the heating element 20 included in the printed layer 14 generates heat due to the irradiation of the energy rays 60. Then, due to the heat of the heating element 20 generated by the energy rays 60, the adhesive strength of the adhesive layer 11 is reduced in a part of the outer periphery of the adhesive layer 11 located in a region corresponding to the printed layer 14 in which the heating element 20 is included.

Heat also distorts the base layer 13 and the printed layer 14. As a result of the base layer 13 and the printed layer 14 distorting in the areas where the adhesive strength of the adhesive layer 11 has decreased, the label 10 shown by the dashed line that was adhered to the substrate 1 floats away from the substrate 1 as shown by the solid line in Figure 3.

In addition, since the printing layer 14 located in the area along the outer periphery of the label body 12 contains the heating element 20, the label 10 can be lifted from the substrate at the outer periphery of the label body 12 by irradiating the label 10 with energy rays 60. Furthermore, as described above, the adhesive layer 11 has a glue suppressing portion 30 formed at a position corresponding to the center of the label body 12, so that the entire label 10 can be easily peeled off from the substrate 1 by lifting the label 10 from the substrate 1 at the outer periphery of the label body 12.

(Base layer)
The base material layer 13 shown in Fig. 1 is a support for the label 10, and is laminated on the back side (adhesive layer 11 side) of the printed layer 14. A conventionally known material can be used as the base material layer 13, and may be, for example, a YUPO (registered trademark) type or PP (polypropylene). Since the base material layer 13 is laminated on the adhesive layer 11 side of the printed layer 14, there is no restriction on the transmittance of the base material layer 13 for transmitting the energy ray 60, and even a white base material layer 13 can be used, for example.

There are no particular restrictions on the material of the base layer 13, but it is preferable that it is one that is easily deformed by heat. Specifically, it is preferable that the base layer 13 has a dynamic viscoelasticity expressed as tan δ (= loss modulus G" (Pa) / storage modulus G' (Pa)) of 0.10 or more at 80°C. This causes the base layer 13 to be significantly distorted by the heat generated by the heating element 20, and the label 10 floats before the heat is conducted to the substrate 1, making it possible to peel the label 10 from the substrate 1 while minimizing the thermal effects on the substrate 1.

(Shrink layer)
The shrink layer 15 is laminated on the front side of the printing layer 14 (the side opposite to the base layer 13) to protect the printing layer 14. The shrink layer 15 is heat shrinkable. By having the shrink layer 15 in the label body 12, the label body 12 itself can be further shrunk by the heat generated by the heating element 20, so that the label 10 can be more easily separated from the object 1. In addition, since the label 10 separates from the object 1 in a predetermined temperature range, even if the energy ray 60 continues to be irradiated, the heat of the heated label 10 is less likely to be transmitted to the object 1, which has the effect of preventing the object 1 from being overheated.

Since the energy rays 60 are irradiated from the shrink layer 15 side of the label 10, for example, if the shrink layer 15 is PET (polyethylene terephthalate) based or PP based, the shrink layer 15 preferably has a transmittance of 70% or more and 100% or less, and more preferably has a transmittance of 70% or more and 95% or less. This allows the energy rays 60 to efficiently penetrate the printing layer 14.

In this embodiment, the label body 12 is formed by laminating the base layer 13, the printing layer 14, and the shrink layer 15 in this order from the adhesive layer 11 side, but this is not limited to the above. For example, the label body 12 does not need to include the shrink layer 15.

In that case, for example, a material having heat shrinkability may be used for the base layer 13. This causes the base layer 13 to heat shrink due to heat generated by the heating element 20, so that the label 10 can be easily peeled off from the substrate 1 even if the label body 12 does not include a shrink layer 15.

The label body 12 may also be constructed by laminating the printed layer 14 and the base layer 13 in this order from the adhesive layer 11 side. By laminating the base layer 13 on the front side of the printed layer 14, the printed layer 14 can be protected by the base layer 13 even without the shrink layer 15.

Furthermore, a protective layer that does not have heat shrinkability may be used instead of the shrink layer 15. In that case, the label body 12 may be constructed by laminating the base layer 13, the printing layer 14, and the protective layer in this order from the adhesive layer 11 side.

It may also be provided by laminating a shrink layer 15 on the label body 12. This causes the shrink layer 15 used for lamination to thermally shrink due to heat generated by the heating element 20, so that the label 10 can be suitably peeled off from the substrate 1 while protecting the label body 12.

(Other examples of label configurations)
Fig. 4 is a plan view showing another example of the configuration of the label 10. Reference numeral 4001 in Fig. 4 is a view of the other example of the label 10 as seen from the front side, and reference numeral 4002 in Fig. 4 is a view of the other example of the label 10 as seen from the back side. Reference numeral 4003 in Fig. 4 is a view of yet another example of the label 10 as seen from the front side, and reference numeral 4004 in Fig. 4 is a view of yet another example of the label 10 as seen from the back side.

As shown in 4001 and 4002 of FIG. 4, in the label 10, the adhesive layer 11 is provided on the entire surface of one surface 12a of the label body 12, and the adhesive suppression portion 30 may be formed in the shape of multiple dots over the entire surface of the adhesive layer 11.

The heating element 20 may also be included in the printing layer 14 located at a corner 16, which is the area where two adjacent sides intersect on the outer periphery of the label body 12 when the label body 12 is viewed in a plan view.

In other words, if the label 10 has a substantially rectangular shape, the heating element-containing portion 141 in the printed layer 14 may be located at any one of the four corners 16.

In this case, the adhesive layer 11 provided over the entire surface of one surface 12a of the label body 12 has a plurality of dot-shaped glue suppressing portions 30 formed over the entire surface. Therefore, the adhesive layer 11 can adhere the entire label body 12 to the object 1 while suppressing the adhesive force, so that the label body 12 can be stably adhered to the object 1.

Furthermore, the printing layer 14 located at the corner 16 of the label body 12 contains a heating element 20. The corner 16 is a part of the label 10 that is easily peeled off, and since the adhesive strength of the adhesive layer 11 is suppressed by the glue suppressing portion 30, the label 10 easily floats off the substrate 1 at the corner 16. Furthermore, since the adhesive strength of the entire adhesive layer 11 is also suppressed by the glue suppressing portion 30, even if the adhesive layer 11 is provided over the entire surface 12a of the label body 12, the label 10 floating at the corner 16 allows the label 10 to be easily peeled off from the substrate 1.

As shown in 4003 and 4004 of FIG. 4, in the label 10, the adhesive layer 11 is provided at a position corresponding to the entire surface on one side 12a of the label body 12, and in the adhesive layer 11, in a region R1 corresponding to the printed layer 14 (heating element-containing portion 141) containing the heating element 20, the adhesive layer 11 may be formed so that the adhesive strength becomes weaker from the center of the adhesive layer 11 toward the outer periphery of the adhesive layer 11.

The adhesive layer 11 is provided at a position corresponding to the entire surface of one surface 12a of the label body 12, so that the label body 12 can be stably adhered to the object to be adhered 1. Furthermore, the adhesive layer 11 in the region R1 corresponding to the heating element-containing portion 141 is formed so that the adhesive strength becomes weaker from the center of the adhesive layer 11 toward the outer periphery of the adhesive layer 11. Therefore, in the region R1 corresponding to the heating element-containing portion 141, the label 10 becomes more easily separated from the object to be adhered 1 the closer it is to the outer periphery of the label body 12, so that the label 10 can be preferably lifted off the object to be adhered 1.

(Other examples of label shapes)
Fig. 5 is a plan view showing another example of the shape of the label 10. In the above embodiment, the label 10 is described as being substantially rectangular, but the shape of the label 10 is not particularly limited. As shown in Fig. 5, the label 10 may have protrusions 17 at both ends and may be substantially T-shaped.

The protruding portion 17 is a portion of the label 10 that is easily peeled off, and by providing the adhesive layer 11 and the heat-generating portion 141 of the printing layer 14 on the protruding portion 17, the label 10 can be more easily peeled off from the substrate 1 by irradiation with the energy beam 60.

(How to remove the label)
6 is a diagram for explaining a peeling method for peeling the label 10 from the target object 1. When peeling the label 10 from the target object 1, as shown in FIG. 6, first, the label 10 is irradiated with energy rays 60 from an irradiation source 50 (irradiation step). In addition, in the printing layer 14 laminated on the adhesive layer 11 that adheres the label 10 to the target object 1, the heating element 20 included in a position corresponding to at least a part of the outer periphery of the adhesive layer 11 is heated by irradiation with the energy rays 60 (heat generation step). As a result, the label 10 is separated from the target object 1 at the location where the heating element 20 generates heat, and the label 10 is peeled off from the target object 1, or a clue for peeling the label 10 from the target object 1 can be created.

Alternatively, air or the like may be blown toward the portion where the label 10 has floated from the substrate 1. This ensures that the label 10 can be peeled off from the substrate 1. As a result, the label 10 can be easily peeled off from the substrate 1 without immersing the substrate 1 in liquid.

(effect)
When recycling or reusing containers, etc., if a label is removed from the container by washing, the container must be dried afterwards. Also, if a label is attached to a container that should not be immersed in liquid, such as an electronic device or an ink cartridge, the label may not be removable from the container by washing.

In addition, one technique for separating labels from containers is to use an alkaline liquid, but in that case, a post-treatment process is required to treat the waste liquid. Also, in the above case, the containers and labels are usually crushed before being separated from each other, so the containers cannot be reused.

Another possible method would be to use an adhesive layer whose adhesive strength weakens when exposed to special light, thereby lowering the adhesive strength and allowing the label to be peeled off from the container. However, this would require the label to be configured so that light can reach the adhesive layer, and would result in restrictions such as the label having to be made of a transparent substrate.

In contrast, in the label 10 according to this embodiment, the label 10 can be peeled off from the substrate 1 by irradiating the label 10 with energy rays 60. This allows the label 10 to be easily peeled off from the substrate 1 without immersing the substrate 1 in liquid. It also makes it possible to peel the label 10 off from the substrate 1 without destroying the substrate 1 or the label 10. In other words, the peeling process in the recycling process (the process of peeling the label 10 off the substrate 1) is carried out in a non-destructive state.

Furthermore, no large-scale equipment is required to peel the label 10 from the substrate 1, and even an average consumer can easily peel the label 10 from the substrate 1 if they have the irradiation source 50.

In addition, since the heating element 20 contained in the printed layer 14 only needs to be irradiated with energy rays 60, the restrictions on the transmittance of each layer constituting the label body 12 are relaxed depending on the stacking order of the printed layers 14 in the label body 12, so the label 10 can be peeled off from the substrate 1 without compromising the design of the label 10.

In addition, when the object 1 is an ink cartridge or the like, it may be desirable to prevent the user from peeling off the label 10 from the object 1 until the object 1 is to be collected. Even in such a case, with the label 10, the outer periphery of the label body 12 adheres to the object 1 when the label 10 is adhered (see 2002 in FIG. 2), so when the object 1 is sold or used, there is no clue on the label 10 for the user to peel off the label 10, and the user cannot peel the label 10 from the object 1. In other words, the label 10 can be peeled off from the object 1 for the first time at the time of the peeling process. Or, a clue for peeling the label 10 from the object 1 can be created for the first time at the time of the peeling process.

In addition, with this configuration, the label 10 can be peeled off from the substrate 1 without immersing it in liquid, making it easy to recycle or reuse the substrate 1. This effect also contributes to achieving, for example, Goal 12 of the Sustainable Development Goals (SDGs) advocated by the United Nations, "Responsible Consumption and Production."

[Test Example]
The test results of one test example of the present invention will be described below. For the sake of convenience, the same reference numerals will be used to designate members having the same functions as those described in the above embodiment, and the description thereof will not be repeated.

In this test example, a peeling test was conducted in which ultraviolet light was irradiated as the energy ray 60 for a predetermined period of time on the labels 10 of Examples 1 to 10, which have different configurations, and a delabeling evaluation and adhesive residue evaluation were performed on each label 10.

The delabeling evaluation was carried out by evaluating the degree of peeling of each label 10 after irradiating each label 10 with ultraviolet light, and was carried out by visually checking the degree of peeling of each label 10 after irradiating each label 10 with ultraviolet light. The evaluation results are shown in the tables shown in Figures 8 and 9. Figure 8 is a table showing some of the results of the peeling test, and Figure 9 is a table showing other results of the peeling test.

In the delabeling evaluation, delabeling evaluation AA indicates a result in which 70% or more of the area of the label 10 peeled off from the support plate 71 within 10 seconds after the start of ultraviolet irradiation. Delabeling evaluation A indicates a result in which 70% or more of the area of the label 10 peeled off from the support plate 71 within 10 to 12 seconds after the start of ultraviolet irradiation. Delabeling evaluation B indicates a result in which 70% or more of the area of the label 10 peeled off from the support plate 71 within 12 to 15 seconds after the start of ultraviolet irradiation.

The adhesive residue evaluation was carried out by irradiating each label 10 with ultraviolet light and then evaluating the presence or absence of adhesive remaining on the support plate 71 where the label 10 had peeled off. The evaluation was carried out by irradiating each label 10 with ultraviolet light and then visually inspecting the peeled off portion of each label 10 on the support plate 71.

In the adhesive residue evaluation, adhesive residue evaluation A indicates that no adhesive was left behind on the area where the label 10 was peeled off. Adhesive residue evaluation B indicates that adhesive was left behind on the area where the label 10 was peeled off.

(Procedure of test)
7 is a diagram showing an example of a peel test device 70 in a test example of the present invention. The peel test device 70 was composed of an irradiation source 50 and a support plate 71. As the irradiation source 50, a UV-LED (ultraviolet light-emitting diode, Phoseon Technology Co., Ltd.) with a wavelength of 385 nm, an output of 20 W, and an irradiation area of 75 mm x 20 mm was used.

First, the irradiation source 50 was placed on a horizontal surface so that ultraviolet light was irradiated from the irradiation source 50 in a horizontal direction. A PE (polyethylene) plate was used as the support plate 71, which replaced the adherend 1, and the label 10 was adhered to the support plate 71. The support plate 71 was fixed to the horizontal surface with a fixture 72 so that the ultraviolet light was irradiated vertically onto the label 10 and the distance L1 from the irradiation source 50 to the label 10 was 40 mm. In this state, the label 10 was irradiated with ultraviolet light at maximum output for a predetermined time (within 15 seconds) and evaluated.

The label 10 was roughly a square with sides of 30 mm. After the label 10 was adhered to the support plate 71, a loaded roller weighing 2 kg was moved back and forth twice on the label 10 to fix the label 10 to the support plate 71. The label 10 left for 24 hours was used as the test sample.

Example 1
The label 10 in Example 1 used a label body 12 including a base layer 13 and a printed layer 14. The base layer 13 was synthetic paper PP with a thickness of 80 μm, the printed layer 14 was made to be 1 μm or more and 2 μm or less in thickness, and black ink was used for the heating element 20. The synthetic paper PP is a film material made of polypropylene that has the properties of paper (opacity and ease of printing). The black ink used was a UV (ultraviolet) curable flexographic ink, and the black ink was cured by UV irradiation to form the printed layer 14 on the entire surface of the label body 12 using a flexographic coater.

The adhesive of the adhesive layer 11 is a medium adhesive 111, and the adhesive layer 11 is formed on the entire surface of the label body 12. Here, the medium adhesive 111 is an adhesive whose adhesive strength is 5.0 N/25 mm or more and 10.0 N/25 mm or less at room temperature.

In Example 1, as shown in FIG. 8, the delabeling evaluation was B and the adhesive residue evaluation was A, confirming that the label 10 peeled off from the support plate 71 satisfactorily.

Example 2
The configuration of the label 10 in the second embodiment is different from that of the label 10 in the first embodiment in that indigo ink is used for the heating element 20, but the other configurations are the same.

In Example 2, as shown in FIG. 8, the delabeling evaluation was B and the adhesive residue evaluation was A, confirming that the label 10 peeled off well from the support plate 71 even when indigo ink was used for the heating element 20.

Example 3
The configuration of the label 10 in Example 3 is different from that of the label 10 in Example 1 in that a transparent varnish containing 15% by weight of an ultraviolet absorbing agent is used as the printing layer 14, but the other configurations are the same.

In Example 3, as shown in FIG. 8, the delabeling evaluation was B and the adhesive residue evaluation was A, confirming that the label 10 peeled off well from the support plate 71 even when a transparent varnish containing an ultraviolet absorber was used in the printing layer 14.

Example 4
The configuration of the label 10 in Example 4 is different from that of the label 10 in Example 1 in that the thickness of the printed layer 14 is 4 μm, but the other configurations are the same. In order to make the thickness of the printed layer 14 4 μm, a bar coater was used to form the printed layer 14.

In Example 4, as shown in FIG. 8, the delabeling evaluation was A, and the adhesive residue evaluation was A, confirming that the label 10 peeled off from the support plate 71 more effectively by making the printing layer 14 thicker.

Example 5
The configuration of the label 10 in Example 5 is the same as that of the label 10 in Example 4 except that the label 10 in Example 5 further includes a shrink layer 15 having a thickness of 15 μm. Note that in the label 10 in Example 5, the shrink layer 15 is provided by applying a UV-curable adhesive onto the printing layer 14 in Example 4 using a flexo coater, and then laminating a shrinkable PP film.

In Example 5, as shown in FIG. 8, the delabeling evaluation was AA and the adhesive residue evaluation was A, confirming that the provision of the shrink layer 15 allowed the label 10 to be more effectively peeled off from the support plate 71.

Example 6
The configuration of the label 10 in Example 6 is the same as that of the label 10 in Example 4 except that the adhesive of the adhesive layer 11 is a medium adhesive 112. Here, the medium adhesive 112 has an adhesive strength in the same range as the medium adhesive 111, and the type of adhesive is different from that of the medium adhesive 111.

In Example 6, as shown in FIG. 8, the delabeling evaluation was B and the adhesive residue evaluation was A, confirming that the label 10 peeled off well from the support plate 71 even when different types of adhesive were used as long as the adhesive strength was similar.

Example 7
The configuration of the label 10 in Example 7 is the same as that of the label 10 in Example 4 except that the adhesive of the adhesive layer 11 is a medium adhesive 113. Here, the medium adhesive 113 has an adhesive strength in the same range as the medium adhesive 111, and the type of adhesive is different from the medium adhesive 111 and the medium adhesive 112.

In Example 7, as shown in Figure 8, the delabeling evaluation was AA and the adhesive residue evaluation was A, confirming that even with adhesives of similar adhesive strength, the label 10 can be more effectively peeled off from the support plate 71 by appropriately selecting the type of adhesive.

Example 8
The configuration of the label 10 in Example 8 is the same as that of the label 10 in Example 4 except that the adhesive of the adhesive layer 11 is a strong adhesive 140. Here, the strong adhesive 140 is an adhesive having an adhesive strength of 15.0 N/25 mm or more and 20.0 N/25 mm or less at room temperature.

In Example 8, as shown in FIG. 8, the delabeling evaluation was A and the adhesive residue evaluation was B, confirming that the label 10 peeled off from the support plate 71 well even when an adhesive with high adhesive strength was used, but that the adhesive was attached to the support plate 71. Therefore, it was confirmed that it is preferable to use a medium adhesive glue 111 to medium adhesive glue 113 as the adhesive when recycling the adhesive-receiving object 1 in actual operation.

Example 9
The configuration of the label 10 in Example 9 is different from that of the label 10 in Example 4 in that the adhesive layer 11 is provided with a glue suppressing portion 30, but the other configurations are the same. 1001 in Fig. 10 is a plan view showing a formation pattern (pattern 1) of the glue suppressing portion 30 in the adhesive layer 11 in Example 9. As shown in 1001 in Fig. 10, the label 10 in Example 9 has the adhesive layer 11 provided on the entire surface of the label body 12, and the glue suppressing portion 30 formed outside the outer peripheral frame range of a width of 5 mm along the outer periphery. In other words, the glue suppressing portion 30 is formed in a region corresponding to the center of the label body 12 when the label body 12 is viewed in a plan view.

The adhesive suppression portion 30 was formed by partially applying a UV-curable adhesive suppression ink to the adhesive layer 11 using a flexo coater.

In Example 9, as shown in FIG. 9, the delabeling evaluation was AA and the adhesive residue evaluation was A, confirming that by forming the adhesive suppression portion 30 in the area corresponding to the center of the label body 12, the label 10 can be more effectively peeled off from the support plate 71.

Example 10
The configuration of the label 10 in Example 10 is different from that of the label 10 in Example 9 in that the range in which the glue suppressing portion 30 is provided in the label body 12 is different, but the other configurations are the same. 1002 in Fig. 10 is a plan view showing a formation pattern (pattern 2) of the glue suppressing portion 30 of the adhesive layer 11 in Example 10. In the label 10 in Example 10, as shown in 1002 in Fig. 10, the adhesive layer 11 is provided on the entire surface of the label body 12, and the glue suppressing portion 30 is formed at the four corners.

In Example 10, as shown in FIG. 9, the delabeling evaluation was AA and the adhesive residue evaluation was A, confirming that forming the adhesive retainer 30 at the four corners allowed the label 10 to be more effectively peeled off from the support plate 71.

〔summary〕
The label (10) according to aspect 1 of the present invention is a label (10) to be adhered to a substrate (1) to be used for recycling or reuse, and comprises an adhesive layer (11) capable of adhering to the substrate (1), and a printed layer (14) laminated on the adhesive layer (11) and including a heating element (20) that generates heat when irradiated with energy rays (60) at a position corresponding to at least a portion of the outer periphery of the adhesive layer (11).

According to the above configuration, the heat of the heating element (20) generated by the energy rays reduces the adhesive strength of the adhesive layer (11) in at least a part of the outer periphery of the adhesive layer (11). In addition, the printed layer (14) is distorted at the location corresponding to the adhesive layer (11) whose adhesive strength has been reduced by the heat of the heating element (20). The printed layer (14) is distorted at the location where the adhesive strength of the adhesive layer (11) has been reduced, and the label (10) floats away from the adherend (1). This makes it possible to peel the label (10) from the adherend (1) or to create a clue for peeling the label (10) from the adherend (1). As a result, it is possible to realize a label (10) that can be easily peeled from the adherend (1) without immersing the adherend (1) in liquid.

In the label (10) according to aspect 2 of the present invention, in the above aspect 1, if the label body (12) is a configuration including a printed layer (14) other than the adhesive layer (11) in the label (10), the heating element (20) is included in the printed layer (14) located in any region of the outer periphery of the label body (12) when the label body (12) is viewed in plan, and the adhesive layer (11) may be provided on one surface (12a) of the label body (12) at a position corresponding to the outer periphery of the label body (12).

According to the above configuration, the adhesive layer (11) is provided on one surface of the label body (12) at a position corresponding to the outer periphery of the label body (12) when the label body (12) is viewed in a plan view, so that the outer periphery of the label body (12) can be adhered to the object to be adhered (1). Therefore, when the label (10) is adhered, the label body (12) does not turn over at the outer periphery of the label body (12), and the label body (12) can be maintained in an adhered state to the object to be adhered (1) while, for example, a user is using the object to be adhered (1).

In addition, since the printing layer (14) located in any region of the outer periphery of the label body (12) contains a heating element (20), the label (10) can be lifted from the substrate (1) at the outer periphery of the label body (12) by irradiating the label (10) with energy rays (60), making it easier to peel the label (10) from the substrate (1).

The label (10) according to aspect 3 of the present invention is the same as in aspect 2 above, except that the heating element (20) is included in a printing layer (14) located in an area along the outer periphery of the label body (12) when the label body (12) is viewed in plan, and the adhesive layer (11) may be formed with a glue suppressing portion (30) that weakens the adhesive strength compared to when the adhesive layer (11) is directly adhered to the object (1).

According to the above configuration, the printing layer (14) located in the area along the outer periphery of the label body (12) contains a heating element (20), so when the energy ray (60) is irradiated to the label (10), the label (10) floats away from the object (1) at the outer periphery of the label body (12). In addition, the adhesive layer (11) is formed with a glue suppressing portion (30) that weakens the adhesive strength compared to when the adhesive layer (11) is directly adhered to the object (1), so by floating the label (10) away from the object (1) at the outer periphery of the label body (12), the entire label (10) can be easily peeled off from the object (1).

The label (10) according to aspect 4 of the present invention is the same as in aspect 2 above, except that the heating element (20) is included in a printed layer (14) located at a corner (16) where two adjacent sides meet on the outer periphery of the label body (12) when the label body (12) is viewed in plan, and the adhesive layer (11) is provided over the entire surface of one surface (12a) of the label body (12), and a glue suppressing portion (30) is formed in the shape of multiple dots over the entire surface of the adhesive layer (11) to weaken the adhesive strength compared to when the adhesive layer (11) is directly adhered to the object (1).

According to the above configuration, the adhesive layer (11) provided on the entire surface of one side of the label body (12) has a plurality of dot-shaped glue suppressing portions (30) formed all over the surface. Therefore, the adhesive layer (11) can adhere the entire label body (12) to the object (1) while suppressing the adhesive force, so that the label body (12) can be stably adhered to the object (1).

Furthermore, the printing layer (14) located at the corner (16), which is the portion where two adjacent sides that form the outer periphery of the label body (12) intersect, contains a heating element (20). The corner (16) is a place where the label (10) is likely to peel off, and since the adhesive strength is further suppressed by the adhesive suppressing portion (30), the label (10) easily floats off the object (1) at the corner (16). Furthermore, since the adhesive strength of the entire adhesive layer (11) is also suppressed by the adhesive suppressing portion (30), even if the adhesive layer (11) is provided over the entire surface of one side of the label body (12), the label (10) can be easily peeled off from the object (1) due to the label (10) floating at the corner (16).

In the label (10) according to aspect 5 of the present invention, in the above aspect 2, the adhesive layer (11) is provided at a position corresponding to the entire surface on one side (12a) of the label body (12), and in the adhesive layer (11), in a region (R1) corresponding to the printed layer (14) containing the heating element (20), the adhesive strength may be formed to become weaker from the center of the adhesive layer (11) toward the outer periphery of the adhesive layer (11).

According to the above configuration, the adhesive layer (11) is provided at a position corresponding to the entire surface on one side of the label body (12), so that the label body (12) can be stably adhered to the object (1). In addition, the adhesive layer (11) in the region (R1) corresponding to the printed layer (14) containing the heating element (20) is formed so that the adhesive strength becomes weaker from the center of the adhesive layer (11) toward the outer periphery of the adhesive layer (11). Therefore, in the region (R1) corresponding to the printed layer (14) containing the heating element (20), the label (10) becomes more easily separated from the object (1) toward the outer periphery of the label body (12), so that the label (10) can be preferably lifted off the object (1).

The label (10) according to aspect 6 of the present invention may further include a heat-shrinkable shrink layer (15) in any of aspects 1 to 5 above.

With the above configuration, the heat generated by the heating element (20) can further shrink the label body (12) itself, making it easier for the label (10) to separate from the substrate (1).

The method for peeling off a label (10) according to aspect 7 of the present invention is a method for peeling off a label (10) adhered to an object (1) from the object (1), and includes an irradiation step of irradiating the label (10) with energy rays (60), and a heating step of causing a heating element (20) included in a printing layer (14) laminated on an adhesive layer (11) that adheres the label (10) to the object (1) at a position corresponding to at least a part of the outer periphery of the adhesive layer (11) to generate heat by irradiation with energy rays (60).

According to the above configuration, the heating element (20) included in the printing layer (14) heats up at least a part of the outer periphery of the adhesive layer (11) due to the energy rays (60) irradiated in the irradiation step, and the heat of the heating element (20) reduces the adhesive strength of the adhesive layer (11). In addition, the heat of the heating element (20) distorts the printing layer (14) at the location corresponding to the adhesive layer (11). The printing layer (14) distorts at the location where the adhesive strength of the adhesive layer (11) is reduced, and the printing layer (14) floats away from the adherend (1). This allows the label (10) to peel off from the adherend (1), or creates a clue for peeling the label (10) from the adherend (1). As a result, the label (10) can be easily peeled off from the adherend (1) without immersing the adherend (1) in liquid.

The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in each embodiment are also included in the technical scope of the present invention.

REFERENCE SIGNS LIST 1: Adhesive object 10: Label 11: Adhesive layer 12: Label body 12a: One surface of the label body 13: Base material layer 14: Printed layer 15: Shrink layer 16: Corner portion 20: Heating element 30: Adhesive suppressing portion 60: Energy ray R1: Region corresponding to the printed layer containing the heating element

Claims (5)

A label to be attached to an adhesive substrate for recycling or reuse,
An adhesive layer capable of adhering to the object to be adhered;
a printing layer laminated on the adhesive layer and including a heating element that generates heat when irradiated with energy rays at a position corresponding to at least a part of the outer periphery of the adhesive layer;
Equipped with a label. When the configuration of the label other than the adhesive layer and including the printing layer is defined as a label body,
the heating element is included in the printing layer located in any region of the outer periphery of the label body when the label body is viewed in plan,
The adhesive layer is provided on one surface of the label body at a position corresponding to the outer periphery of the label body.
The label of claim 1. the heating element is included in the printing layer located in a region along the outer periphery of the label body when the label body is viewed in plan,
The adhesive layer is formed with a glue suppressing portion that weakens the adhesive strength compared to when the adhesive layer is directly adhered to the adherend.
The label of claim 2. Further comprising a heat-shrinkable shrink layer.
The label of claim 1. A label peeling method for peeling a label adhered to an adhesive object from the adhesive object, comprising the steps of:
an irradiation step of irradiating the label with an energy beam;
a heating step of heating a heating element included in a printed layer laminated on an adhesive layer that adheres the label to the adhesive target at a position corresponding to at least a part of an outer periphery of the adhesive layer by irradiating the energy beam,
How to remove the label.

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