Recyclable shrink labels and articles

Abstract

The present disclosure provides a recoverable shrink label comprising a heat shrink film having a first surface and a second surface opposite the first surface; and a light blocking layer disposed adjacent to the first surface and including a light blocking component, the light blocking layer configured such that the recyclable shrink label blocks at least 80% of incident light having a wavelength in the range of 200 nm to 900 nm. The recoverable shrink label may also include a marking layer. The recoverable shrink label may also include a high opacity layer. The recoverable shrink label may be applied to a container, for example, a recoverable container. Comprising the recoverable shrink label can be recovered in a process in which both the container and the label are identified as resin and can be introduced into a corresponding recovery stream. In some cases, the container and the label both comprise PET.

Description

[0001] This application is a divisional application of the invention patent application with application number 2022800384447 filed on May 13, 2022 and invention name “Recyclable heat shrinkable film for recyclable containers”.

[0002] Related Applications

[0003] This application claims priority to U.S. Provisional Patent Application No. 63 / 188,794, filed on May 14, 2021, the entire contents of which are incorporated herein. Technical Field

[0004] The present application relates to recyclable packaging, and in particular to a recyclable shrink label and corresponding products. Background Art

[0005] The global packaged consumer goods market is eager to use recyclable packaging for most products. Clear PET packaging provides a cost-effective and recyclable packaging option. Dairy, food, health supplements and other markets also require light-protective packaging to block light waves that are harmful to ingredients from affecting the shelf life and performance of these products. Traditionally, harmful light waves are blocked using pigmented bottles or containers and / or white shrink films with or without printed functional light-blocking layers. The market for recycling pigmented PET is very small and most of these bottles and containers are not recycled.

[0006] Therefore, for many markets, including the food and health products markets, there is still a need for recyclable light protection packaging products.

[0007] Any discussion of prior publications and other prior knowledge is not an admission that such material is published, known or forms part of the common general knowledge. Summary of the invention

[0008] A recyclable shrink label is disclosed herein.

[0009] According to one embodiment, a recyclable shrink label includes a heat shrink film having a first surface and a second surface opposite to the first surface; and a light blocking layer disposed adjacent to the first surface and including a light blocking component, the light blocking layer being configured such that the recyclable shrink label blocks at least 80% of incident light having a wavelength in the range of 200 nanometers to 900 nanometers. The heat shrink film may have a thickness of 15 micrometers to 100 micrometers or 30 micrometers to 80 micrometers.

[0010] The recyclable shrink label may further include a marking layer. The marking layer may be arranged on the first surface. The recyclable shrink label may further include a high opacity layer. The high opacity layer may contain a white pigment. The high opacity layer may be arranged between the marking layer and the light blocking layer.

[0011] The heat shrinkable film may include polyester, polyolefin or a combination thereof, or may be made of these materials. In some cases, the heat shrinkable film includes polyethylene terephthalate (PET), modified polyethylene terephthalate (PETG or PET-G), polyvinyl chloride (PVC), polystyrene or oriented polystyrene (OPS), polylactic acid (PLA), polypropylene (PP), polyethylene (PE) or a combination thereof, or may be made of these materials. In some cases, the heat shrinkable film may include polyethylene terephthalate (PET), modified polyethylene terephthalate (PETG or PET-G), polyvinyl chloride (PVC), polystyrene or oriented polystyrene (OPS), polylactic acid (PLA), polypropylene (PP), polyethylene (PE) or a combination thereof. In some cases, the heat shrinkable film may include polyethylene terephthalate (PET), modified polyethylene terephthalate (PETG or PET-G), polyvinyl chloride (PVC), polystyrene or oriented polystyrene (OPS), polylactic acid (PLA), polypropylene (PP), polyethylene (PE) or a combination thereof. In some cases, the heat shrinkable film may include polyethylene terephthalate (PET).

[0012] When heated to 100°C, the heat shrink film may shrink or contract by about 1% to about 90%. The heat shrink film may shrink or contract by about 1% to about 90% in the transverse direction. When heated to 100°C, the entire recyclable shrink label may shrink or contract by about 1% to about 90%. The entire recyclable shrink label may shrink or contract by about 1% to about 90% in the transverse direction.

[0013] The high opacity layer may comprise a pigment selected from titanium dioxide (TiO2), precipitated calcium carbonate (PCC), aluminum silicate, aluminum oxide, mica-based pigments coated with a thin layer of white pigment, or combinations thereof.

[0014] The light-blocking component may include metal particles. The metal particles may have a particle size of 0.1 micron to 100 microns. The light-blocking component may include zinc, aluminum, copper, silver or their alloys, titanium dioxide, carbon black, mica, reflective pigments, polymers capable of blocking light, minerals capable of blocking light or their combinations, or be composed of these materials. The light-blocking layer may be present on the label in an amount of 0.5 ppr to 25 ppr. The light-blocking component may be present in an amount of 0.1 ppr to 10 ppr, 0.2 ppr to 5 ppr or 0.3 ppr to 3 ppr.

[0015] According to one embodiment, a product is provided, which includes a container having an outer surface; and the above-mentioned recyclable shrink label arranged on the container. In some embodiments, the first surface of the heat shrink film faces the outer surface of the container. The container may contain a polymer, glass, metal or a combination thereof, or be made of these materials. The container may contain polyethylene terephthalate (PET), or be made of polyethylene terephthalate (PET) (for example, composed of PET). The container may contain transparent polyethylene terephthalate (PET), or be made of transparent polyethylene terephthalate (PET) (for example, composed of transparent PTE). The recyclable shrink label may contain polyethylene terephthalate (PET), or be made of polyethylene terephthalate (PET). In some cases, the polyethylene terephthalate (PET) forms the outermost layer of the recyclable shrink label.

[0016] According to one embodiment, a method for manufacturing a label for a container is provided, the method comprising depositing a marking layer on a heat shrink film; optionally depositing a high opacity layer on the marking layer; and depositing a light-blocking composition on the marking layer, the heat shrink film or the high opacity layer, wherein the light-blocking layer comprises one or more light-blocking components, and wherein the label is capable of blocking at least 80% of incident light having a wavelength in the range of 200 nanometers to 900 nanometers.

[0017] According to one embodiment, a method for recycling an article is provided, the article comprising a container defining an outer surface; and the above-mentioned recyclable shrink label disposed on the container, optionally with the first surface facing the outer surface of the container, the method comprising: determining that the container and the recyclable shrink label contain polyethylene terephthalate (PET); introducing the article into a polyethylene terephthalate (PET) recycling stream; and washing the article to remove ink and pigment from the recyclable shrink label. The washed article can be transparent and not contaminated by light-blocking components or other pigments or inks. The article can be washed in an alkaline bath. The article can be cut into pieces before washing. According to one embodiment, during the recycling process, the ink and coating are cleanly separated from the PET heat shrink film, thereby allowing the pure PET to be recovered and processed into a reusable resin.

[0018] The above summary of the present invention is not intended to illustrate every disclosed embodiment or every implementation of the present invention. The following description more specifically illustrates exemplary embodiments. Guidance is provided by lists of examples at multiple locations in this application, and these examples can be used in various combinations. In each case, the enumerated list is only a representative group and should not be interpreted as an exclusive list.

[0019] According to one embodiment, the present invention provides a recyclable shrink label, comprising: a heat shrink film having a first surface and a second surface opposite to the first surface, the heat shrink film having a thickness of 15 to 100 microns or 30 to 80 microns; and a light blocking layer arranged adjacent to the first surface and comprising a light blocking component, the light blocking layer being configured such that the recyclable shrink label blocks at least 80% of incident light having a wavelength in the range of 200 to 900 nanometers.

[0020] According to another embodiment, the recyclable shrink label further comprises a marking layer, optionally wherein the marking layer is arranged on the first surface.

[0021] According to another embodiment, the recyclable shrink label further comprises a high opacity layer, which optionally contains a white pigment.

[0022] According to another embodiment, the recyclable shrink label includes a marking layer, and wherein the high opacity layer is disposed between the marking layer and the light blocking layer.

[0023] According to another embodiment, the heat shrinkable film comprises polyester, polyolefin, or a combination thereof.

[0024] According to another embodiment, the heat shrinkable film includes polyethylene terephthalate (PET), modified polyethylene terephthalate (PETG or PET-G), polyvinyl chloride (PVC), polystyrene or oriented polystyrene (OPS), polylactic acid (PLA), polypropylene (PP), polyethylene (PE), or a combination thereof.

[0025] According to another embodiment, the heat shrinkable film is in the form of a sleeve or a tube.

[0026] According to another embodiment, when heated to 100° C., the heat shrinkable film retracts or shrinks by about 1% to about 90%, and optionally, the heat shrinkable film retracts or shrinks by about 1% to about 90% in a transverse direction.

[0027] According to another embodiment, wherein the entire recyclable shrink label retracts or shrinks by about 1% to about 90% when heated to 100° C., optionally wherein the entire recyclable shrink label shrinks by about 1% to about 90% in a transverse direction.

[0028] According to another embodiment, the high opacity layer comprises a pigment selected from titanium dioxide (TiO2), precipitated calcium carbonate (PCC), aluminum silicate, aluminum oxide, mica-based pigments coated with a thin layer of white pigment, or combinations thereof.

[0029] According to another embodiment, the light-blocking component comprises metal particles. Optionally, the metal particles have a particle size of 0.1 micrometer to 100 micrometers.

[0030] According to another embodiment, the light-blocking component comprises zinc, aluminum, copper, silver or alloys thereof, titanium dioxide, carbon black, mica, reflective pigments, light-blocking polymers, light-blocking minerals or combinations thereof.

[0031] According to another embodiment, the light blocking layer is present in an amount of 0.5 ppr to 25 ppr.

[0032] According to another embodiment, the light blocking layer contains 0.1 ppr to 10 ppr, 0.2 ppr to 5 ppr, or 0.3 ppr to 3 ppr of light blocking components.

[0033] According to another embodiment, the present invention provides an article, comprising: a container having an outer surface; and a recyclable shrink label according to any of the above embodiments arranged on the container, optionally wherein the first surface of the heat shrink film faces the outer surface of the container.

[0034] According to another embodiment, the container comprises a polymer, glass, metal, or a combination thereof.

[0035] According to another embodiment, the container comprises polyethylene terephthalate (PET), optionally, the container consists of polyethylene terephthalate (PET), optionally, the container comprises transparent polyethylene terephthalate (PET).

[0036] According to another embodiment, the recyclable shrink label comprises polyethylene terephthalate (PET), and, optionally, wherein the polyethylene terephthalate (PET) forms an outermost layer of the recyclable shrink label.

[0037] According to another embodiment, the present invention provides a method for manufacturing a label for a container, comprising: depositing a marking layer on a heat shrinkable film; optionally depositing a high opacity layer on the marking layer; and depositing a light-blocking composition on the marking layer, the heat shrinkable film or the high opacity layer, wherein the light-blocking layer contains one or more light-blocking components, and wherein the label is capable of blocking at least 80% of incident light having a wavelength in the range of 200 nanometers to 900 nanometers.

[0038] According to another embodiment, the present invention provides a method for recycling an article, the article comprising a container defining an outer surface; and a recyclable shrink label according to any of the preceding embodiments arranged on the container, optionally, the first surface facing the outer surface of the container, the method comprising: determining that the container and the recyclable shrink label contain polyethylene terephthalate (PET); introducing the article into a polyethylene terephthalate (PET) recycling stream; and washing the article to remove ink and pigment from the recyclable shrink label.

[0039] According to another embodiment, the cleaned article is transparent and is not stained by light-blocking components or other pigments or inks.

[0040] definition

[0041] The words "preferred" and "preferably" refer to embodiments of the present invention that can provide certain benefits in certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. In addition, the description of one or more preferred embodiments does not mean that other embodiments are useless, nor is it intended to exclude other embodiments from the scope of the present invention.

[0042] The term "comprise" and its variations do not have a limiting meaning when they appear in the specification and claims. Such terms should be understood to imply the inclusion of the stated steps or elements or a group of steps or elements, but not the exclusion of any other steps or elements or a group of steps or elements.

[0043] "Consisting of" means including and limited to any item following the phrase "consisting of." Thus, the phrase "consisting of" indicates that the listed elements are required or mandatory, and that no other elements are present. "Consisting essentially of" means including any elements listed after the phrase, and limited to other elements that do not interfere with or contribute to the activity or function specified in the disclosure of the listed elements. Thus, the phrase "consisting essentially of" indicates that the listed elements are required or mandatory, but other elements are optional and may or may not be present, depending on whether they substantially affect the activity or function of the listed elements.

[0044] The term "substantially" as used herein has the same meaning as "almost completely" and may be understood to modify the following term by at least about 90%, at least about 95%, or at least about 98%. The term "insubstantially" as used herein has the same meaning as "insignificantly" and may be understood to have the opposite meaning of "substantially", i.e., modifying the following term by no more than 10%, no more than 5%, or no more than 2%.

[0045] Unless otherwise specified, "a," "an," "the," and "at least one" are used interchangeably to mean one or more than one.

[0046] As used herein, the term "or" is generally used in its ordinary meaning, including "and / or," unless the content clearly dictates otherwise.

[0047] The term "and / or" means one or all of the listed elements, or a combination of any two or more of the listed elements.

[0048] Any reference to a standard method (eg, ASTM, TAPPI, AATCC, etc.) refers to the most recent available version of that method at the time of filing this disclosure, unless otherwise indicated.

[0049] Additionally, the recitations of numerical ranges herein by endpoints include all numbers subsumed within that range (eg, 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.).

[0050] As used herein, “up to” a certain number (eg, up to 50) includes the number (eg, 50).

[0051] The terms "within the range" or "within a range" (and similar expressions) include the endpoints of the stated range.

[0052] For any method disclosed herein including discrete steps, these steps may be performed in any feasible order. Moreover, any combination of two or more steps may be performed simultaneously, depending on the circumstances.

[0053] Unless otherwise specified, all headings are for the convenience of the reader and should not be used to limit the meaning of the text that follows the heading.

[0054] References in this specification to "one embodiment," "an embodiment," "certain embodiments," or "some embodiments," etc., mean that a particular feature, configuration, composition, or characteristic described in conjunction with that embodiment is included in at least one embodiment of the present disclosure. Thus, the appearance of such phrases in various places in this specification does not necessarily refer to the same embodiment of the present disclosure. Furthermore, in one or more embodiments, the particular features, configurations, compositions, or characteristics may be combined in any appropriate manner.

[0055] Unless otherwise indicated, all numerical values ​​used to express the quantity of ingredients, molecular weight, etc. in the specification and claims should be understood to be modified by the term "approximately" in all cases. The term "approximately" as used in conjunction with a measured amount herein refers to the variation of the measured amount as expected by a person of ordinary skill in the art when making the measurement and taking a level of care commensurate with the purpose of the measurement and the accuracy of the measuring equipment. Accordingly, unless otherwise indicated, the numerical parameters listed in the specification and claims are approximate values, which can vary depending on the desired properties that the present invention attempts to obtain. Each numerical parameter should be constructed at least according to the number of significant figures reported and by applying general rounding techniques, but this is not intended to limit the basic principle that is equivalent to the scope of the claims.

[0056] Although the numerical ranges and parameters setting forth the overall scope of the invention are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible. However, all numerical values ​​necessarily include a certain range resulting from the standard deviation of their respective testing measurements.

[0057] The terms "polymer" and "polymeric material" include, but are not limited to, organic homopolymers, copolymers, such as block, graft, random and copolymers, terpolymers, etc., and blends and modifications thereof. In addition, unless otherwise specifically limited, the term "polymer" shall include all possible geometric configurations of the material. These configurations include, but are not limited to, isotactic, syndiotactic and atactic symmetries.

[0058] The term "copolymer" refers to a polymer containing two or more different monomer units or segments, including terpolymers, tetrapolymers, and the like.

[0059] As used herein, the term "ink" refers to a colored material used for writing and printing. Generally speaking, ink has four main components: (1) a colorant, which consists of a pigment, a dye, or a mixture of pigments and / or dyes that defines the color of the colorant, (2) a resin, which is a soluble or solvent-based binder that holds the colorant on the substrate, (3) an optional solvent or water for dissolving the resin (the solvent or water is removed after printing on the label), and (4) an optional additive for adjusting the properties of the ink. Pigments can be organic and inorganic. The inks herein can be divided into metallic inks and non-metallic inks. As used herein, the term "metallic ink" refers to an ink to which metal flakes or powders are added as pigment additives to the ink. Metallic inks exhibit reflectivity or gloss when printed. Therefore, the "non-metallic ink" herein refers to an ink that does not contain such metal flakes or powder components.

[0060] As used herein, the term "opaque" refers to a substrate or printed substrate having an opacity greater than or equal to 50%.

[0061] As used herein, the term "opacity" refers to a property of a substrate or printed substrate that measures the ability of the substrate to hide or conceal an object placed behind the substrate relative to the observation point. Opacity can be reported as the ratio of the diffuse reflectance of a substrate backed by a black object with a reflectivity of 0.5% to the diffuse reflectance of the same substrate backed by a white object with an absolute reflectivity of 89%, expressed as a percentage. Opacity can be measured according to the method described in ASTM D 589-97 "Standard Test Method for Opacity of Paper" (15 ° / diffuse light source A, 89% reflectivity backing and paper backing). A substrate with high opacity will not allow a large part of the light (if any) to pass through the substrate. A substrate with low opacity will allow a large part of the light (if not almost all) to pass through the substrate. Opacity can range from 0 to 100%. As used herein, the term "low opacity" refers to a substrate or printed substrate with an opacity of less than 50%. As used herein, the term "high opacity" refers to a substrate or printed substrate with an opacity greater than or equal to 50%.

[0062] As used herein, the term "mark" refers to a sign or indication that can be used to convey information. The information conveyed can be an indication of a source, the characteristics of the product in the package, the quantity of the product in the package, the quality of the product in the package, or any other information. A mark can be a symbol, such as a graphic similar to a target for training archers, which indicates a specific retail store. A mark can be a text representing any language or combination of languages ​​for oral communication. A mark can be a pattern of color, line, or a combination thereof. A mark can be a diagram of a tangible object, such as an apple, which indicates the source of a computer of a specific brand. A mark can be an artistic drawing depicting a tangible object or a fictional work or a logo of any kind. A single point of a single color can be a mark. A mark can be the type, texture, smell, or rustling sound of the material used to form the package. A mark can be a combination of any and all of the aforementioned marks.

[0063] As used herein, the term "ppr" means pounds per ream and is used as a unit of measurement for dry pounds of ink or coating per unit area of ​​a substrate (eg, film or label). A ream is understood to be 3000 square feet (approximately 289 square meters).

[0064] As used herein, the term "BCM" refers to billion cubic micrometers per square inch (μm 3 / inch 2 ), and is used as a unit of measurement for the liquid volume of an ink or coating.

[0065] The term "line screen" as used herein refers to how many halftone lines are printed per linear inch.

[0066] The term "viscosity" as used herein refers to the flow rate of a liquid and is measured using a calibrated No. 2 Zahn viscosity cup.

[0067] As used herein, the term "COF" refers to dynamic coefficient of friction and static coefficient of friction values. COF can be measured according to the method described in ASTM D1894-14 "Standard Test Method for Static and Dynamic Coefficient of Friction of Plastic Film and Sheeting". BRIEF DESCRIPTION OF THE DRAWINGS

[0068] The present disclosure will be further explained below with reference to the accompanying drawings.

[0069] These idealized drawings are not drawn to scale and are merely illustrative rather than restrictive.

[0070] Figure 1A schematically illustrates one embodiment of a disclosed article according to one embodiment;

[0071] Figure 1B schematically illustrates one embodiment of a disclosed article according to one embodiment;

[0072] Figure 1C schematically illustrates one embodiment of a disclosed article according to one embodiment;

[0073] Figure 1D schematically illustrates one embodiment of a disclosed article according to one embodiment;

[0074] Figure 1E schematically illustrates one embodiment of a disclosed article according to one embodiment;

[0075] Figure 2 is a schematic diagram of an article including a tag of the present disclosure according to one embodiment;

[0076] Figure 3-5 is a graphical representation of the data from Example 1. DETAILED DESCRIPTION

[0077] The present disclosure relates to an opaque and recyclable label. The present disclosure also relates to an opaque and recyclable shrinkable label.

[0078] The term "label" is used broadly herein. Although many of the embodiments described herein may be characterized as shrink sleeves, the present disclosure and the term "label" are not limited to these embodiments. The label may cover at least some colorless or transparent portions of the package. The label may be used to block light from reaching the product within the package. The label may be used to provide graphical elements and information about the product, such as product information (e.g., ingredient list and / or nutrition table) required by regulations (if applicable).

[0079] According to one embodiment, the label of the present disclosure has a layered structure. The layered structure may include one or more shrink film layers and one or more light-blocking (opaque) layers. The layered structure may also include other layers, such as additional polymer layers, markings, adhesive layers, slip coatings, protective top layers, another functional layer, or combinations thereof. Such additional layers may be placed between shrink film, marking layers, high opacity layers, or light-blocking layers, or may be placed on the outside of any such layers. The shrink film has a first surface and a second surface opposite to the first surface. When the label is applied to a container (e.g., a bottle), the first surface may be the face facing the container, and the second surface may face the outside of the container. The light-blocking layer may be arranged adjacent to the first surface. That is, generally, the light-blocking layer may be arranged between the shrink film and the container. Other layers (if any) may be arranged adjacent to the first surface or the second surface. The term "adjacent" is used herein to indicate which side of the layer is closest to the label. Additional optional layers may be arranged between adjacent layers. The term "directly adjacent" is used to indicate that the layers discussed are in contact with each other and there is no intermediate layer.

[0080] It is desirable that the label blocks light (e.g., ambient light and sunlight, e.g., from 200 nm to 900 nm) so that the contents of the container covered by the label can be protected from light. It is also desirable that the label is recyclable. Typically, for a transparent, crystallizable heat shrinkable film (e.g., PET shrink film), if no ink remains on the film after an alkali wash cycle typically used in the PET recycling process, the film is considered recyclable.

[0081] Previously, white PET film with a black coating printed on the inside of the label was the only shrink label solution that met the ideal light blocking threshold. White PET cannot be recycled with clear PET bottles or containers, so these products are not recycled but sent to landfills. According to one embodiment, the label of the present disclosure is light blocking and provides the ability to maintain and improve product shelf life while maintaining the recyclability of clear PET packaging using light blocking clear shrink film.

[0082] According to one embodiment, the inks (including light-blocking inks) used in the labels of the present disclosure are designed to be washed off the film during the recycling process, thereby allowing recycling of the labels and the containers they cover.

[0083] In addition, according to one embodiment, the label of the present disclosure allows the use of transparent PET bottom container or bottle, which maintains the recyclability of the container or bottle. The label can also potentially reduce or eliminate the need to include any additional additives (such as pigments) in the container itself. For example, the label can be used on transparent, hard PET containers and bottles. Any ink and coating printed on the PET shrink film can be formulated to be washed off from the film during the recycling process, thereby allowing the transparent PET film below to be recycled together with the transparent PET hard plastic. The ink and coating can be formulated to gather together by a reaction similar to coagulation during the rinsing process, which prevents or reduces the ink and coating from contaminating the transparent film and rigid PET at the bottom of the PET alkali recovery bath process equipment. For example, the ink and coating can be cross-linked and / or have additives that help smaller particles to gather into larger particles during the cleaning process. This larger particle can then be filtered out from the rinse water, which helps to prevent contamination of the PET film and the transparent PET hard plastic.

[0084] membrane

[0085] According to one embodiment, the label comprises a heat shrinkable film or a heat shrink film. The terms "heat shrink film" and "shrink film" are used interchangeably herein. Any suitable heat shrink film may be used. In some embodiments, the heat shrink film is a polyester heat shrink film used in the packaging industry. The heat shrink film may also be described as a film that is not heat stable and thus shrinks when exposed to heat.

[0086] The heat shrinkable film is a substantially two-dimensional polymer film having two major surfaces. The term "substantially two-dimensional" is used to refer to an object having much larger dimensional measurements in two dimensions compared to much smaller dimensional measurements in the third dimension (e.g., thickness). In some embodiments, a useful heat shrinkable film or an article comprising such a heat shrinkable film shrinks by 1% to 90% in the transverse direction (TD) and by up to 10% in the machine direction (MD). In some embodiments, a useful heat shrinkable film or an article comprising such a heat shrinkable film shrinks by 1% to 90% in the machine direction and by up to 10% in the transverse direction. As used herein, "transverse direction" refers to a direction perpendicular to the working direction. As used herein, "machine direction" refers to a direction parallel to the working direction.

[0087] There is no particular restriction on the composition of the heat shrinkable film (whether two-dimensional or three-dimensional), and the heat shrinkable film may include a high-density polymer or a low-density polymer, or a combination thereof. A low-density polymer having a density of less than 1 gram per cubic centimeter may be preferred. Such a low density allows flotation separation from a denser substrate with water during recycling. In some embodiments, the label comprises a heat shrinkable film having a density of 1 gram per cubic centimeter or less.

[0088] According to one embodiment, the label comprises a heat shrink film having a thickness of 15 microns or more, 30 microns or more, 35 microns or more, 37 microns or more, 40 microns or more, 45 microns or more, 50 microns or more, or even 60 microns or more. The preferred heat shrink film is composed of a film having a thickness of no more than 100 microns or less, no more than 90 microns or less, no more than 90 microns or less, no more than 85 microns or less, no more than 80 microns or less, no more than 75 microns or less, no more than 70 microns or less, no more than 65 microns or less, or even no more than 60 microns or less. In some embodiments, the thickness of the heat shrink film ranges from 15 microns to 100 microns, 30 microns to 80 microns, 40 microns to 60 microns, or even 40 microns to 55 microns.

[0089] According to one embodiment, the label includes a heat shrink film that shrinks when heated to a shrink start temperature or higher. The shrink start temperature may be higher than 22.5°C, or in the range of about 40°C to about 200°C. The shrinkage of the heat shrink film is usually measured using a hot water bath method, in which the film is immersed in a hot water bath for 10 seconds. The measurement may be repeated at different temperatures, for example at 100°C and 80°C. The shrinkage may be reported at a given temperature, or shown as a shrinkage curve. The shrinkage values ​​given herein are measured at 100°C. When heated to 100°C, the heat shrink film shrinks 1% or more, 2% or more, 5% or more, 10% or more, 20% or more, 30% or more, 40% or more, or 50% or more of the size before heating. When heated to 100°C, the heat shrink film shrinks 90% or less, 80% or less, 75% or less, 70% or less, or 50% or less of the size before heating. When heated to 100° C., the heat shrink film can shrink 1% to 90%, 2% to 80%, or 5% to 70%. Shrinkage can occur in the machine direction, the transverse direction, or both. In some embodiments, the heat shrink film shrinks primarily only in the transverse direction. In some embodiments, the heat shrink film shrinks primarily only in the machine direction.

[0090] In some embodiments, the polymer film that can be used in the label has balanced shrinkage characteristics. The balanced shrinkage characteristics enable the film to tension the pleats and wrinkles initially formed in the label when the label is applied to a curved surface, and the pleats and pleats are smoothed, and the graphic deformation of the label is minimized. In some embodiments, the film that can be used in the label has unbalanced shrinkage characteristics. Films with unbalanced shrinkage (i.e., films with a very high degree of shrinkage in one direction and a lower to moderate degree of shrinkage in another direction) may be particularly useful. In some embodiments, particularly useful films are films with one-dimensional shrinkage (e.g., shrinkage in the transverse direction) because films with one-dimensional shrinkage can provide the ability to more easily pre-deform the markings formed thereon compared to films with biaxial shrinkage. In some embodiments, the film can be used in a process known as "roll-to-roll shrinkage", in which the film shrinks primarily in the machine direction.

[0091] Preferably, the shrink film is heat shrinkable but still has sufficient hardness (e.g., modulus) to be dispensed using conventional label application equipment and converting processes, including handling, printing, coating, slitting, sewing, cutting, and label application. The desired hardness of the film depends on the size of the label, the speed of application, the shape and moisture content of the container surface, and the label application equipment used.

[0092] The shrink film can be manufactured by conventional processes. For example, the shrink film can be produced using a blowing, calendering or tenter extrusion process.

[0093] The shrink film that can be used in the label can be a single-layer structure or a multilayer structure. One or more layers of the shrink film can be formed by a polymer selected from various types of polymers, for example, polyester and polyolefin. The exemplary specific polymer or polymer type that can be used to form the shrink film can, for example, include polyethylene terephthalate (PET), modified polyethylene terephthalate (PETG or PET-G), polyvinyl chloride (PVC), polystyrene or oriented polystyrene (OPS), polylactic acid (PLA), copolymers, non-petroleum-based biopolymers, and their copolymers and blends. Other exemplary specific types of polymers that can be used to form the shrink film can include polyolefins, such as polypropylene (PP), polyethylene (PE), and their copolymers and blends. In certain embodiments, exemplary specific copolymers can, for example, include copolymers of PP and PE. In a preferred embodiment, the shrink film includes polyethylene terephthalate (PET) and can be recycled together with PET bottles. In certain embodiments, the shrink film is composed of polyethylene terephthalate (PET).

[0094] Shrink film is usually applied to a substrate or a container (e.g., bottle, can, tube, etc.) or a plurality of containers (e.g., multi-pack container) on or around the polymer film. Two parts of the film (e.g., two edges) can be combined to form a seal or seam, thereby forming a sleeve or tube structure. When heated to 100 ° C, the shrink film retracts or shrinks 1% or more, 2% or more, 5% or more, 10% or more, 20% or more, 30% or more, 40% or more, or 50% or more. When heated to 100 ° C, the shrink film can retract or shrink 90% or less, 80% or less, 75% or less, 70% or less, or 50% or less of its size before heating. When heated to the shrink start temperature or higher temperature, the shrink film can retract or shrink 1% to 90%, 2% to 80%, or 5% to 70%. Shrinkage can be carried out in the machine direction, the transverse direction, or both directions. In some embodiments, the heat shrink film mainly shrinks only in the transverse direction. In some embodiments, the heat shrink film mainly shrinks only in the machine direction. The amount of shrinkage of the shrink film may depend largely on the container around which the shrink film is to be shrunk, or may be selected based on the container. The film shrinks to conform to the contours of the underlying article. In one embodiment, the shrink film is microporous to allow trapped air to be released from the interface between the label and the article to which the label is adhered. In another embodiment, the shrink film is liquid permeable to allow fluid to escape from the surface of the adhesive or the article. In one embodiment, vents or slits are provided in the shrink film. In some embodiments, perforations, pinholes, or such features may be avoided as desired to maximize light blocking properties.

[0095] The layer of the shrink film or the layer applied to the shrink film may optionally contain pigments, fillers, stabilizers, light protectants or other suitable modifiers if desired.

[0096] The shrink film may have any suitable color. However, for recyclability, useful shrink films may specifically include transparent shrink films and white shrink films (e.g., white floatable films). Transparent shrink films may be made white by including one or more additional layers containing a pigment that makes the shrink film appear white. White shrink films may also be prepared, for example, by adding a white pigment during extrusion or molding.

[0097] Useful shrink films may also include a layer of an ink-loving composition that enhances the printability of the shrink film and the quality of the printed layer obtained therefrom. A variety of such compositions are known in the art, and these compositions typically include a binder and a pigment, such as silica or talc, dispersed in the binder. The presence of an ink-loving composition can reduce the drying time of certain inks. Such an ink-loving composition is described in U.S. Pat. No. 6,153,288 (Shih et al.), the disclosure of which is incorporated herein by reference.

[0098] The adhesion of ink on the surface of the polymer shrink film can be improved by techniques known to those skilled in the art as needed or desired. For example, as described above, before applying the ink, an ink primer or other ink adhesion promoter can be applied to the surface layer of the shrink film. Alternatively, the surface of the shrink film can be treated by methods such as corona treatment or flame treatment to improve the adhesion of the ink on the polymer film layer.

[0099] Available ink primers can be transparent or opaque, and the primer can be a solvent-based, water-based or UV-based digital printing ink diluted with known solvents and / or additives to achieve the viscosity required for a specific printing process. In one embodiment, the primer is radiation-curable (e.g., UV-curable). The ink primer can include a lacquer and a diluent. The lacquer can be composed of one or more polyolefins, polyamides, polyesters, polyester copolymers, polyurethanes, polysulfones, polyvinylidene chloride, styrene-maleic anhydride copolymers, styrene-acrylonitrile copolymers, ionomers based on sodium salts or zinc salts or ethylene methacrylic acid, polymethyl methacrylate, acrylic polymers and copolymers, polycarbonates, polyacrylonitrile, ethylene-vinyl acetate copolymers, and mixtures of two or more thereof. Examples of usable diluents include alcohols, such as ethanol, isopropanol and butanol; esters, such as ethyl acetate, propyl acetate and butyl acetate; aromatic hydrocarbons, such as ketones, such as acetone and methyl ethyl ketone; aliphatic hydrocarbons, such as heptane; and mixtures thereof. The ratio of the lacquer to the diluent depends on the viscosity required to apply the ink primer, and the selection of such viscosity is within the skill of the art. The thickness of the ink primer layer can be about 0.5 microns to about 20 microns, about 1 micron to about 4 microns, or about 1.5 microns to about 3 microns.

[0100] A transparent or opaque polymeric top layer or outer layer may be present in the labels of the present disclosure. The top layer or outer layer can provide the desired protective properties for the label before and after the label is attached to the article (e.g., container). In some embodiments, the presence of a transparent or opaque top layer on the print layer can provide additional properties, such as antistatic properties, hardness and / or weather resistance, and the top layer can protect the print layer from weather, sunlight, wear, moisture, water, etc. The transparent or opaque top layer can enhance the properties of the underlying print layer to provide a more shiny and richer image. The transparent or opaque top layer can change the aesthetics of the underlying print layer or label (e.g., matte effect or soft touch effect). The protective transparent protective layer can also be designed to be wear-resistant, radiation-resistant (e.g., UV-resistant), chemical-resistant, and heat-resistant, thereby protecting the label (especially the print layer) from degradation caused by these reasons. The outer layer can also contain an antistatic agent or an anti-blocking agent to make it easier to handle when the label is applied to the container at high speed. The layer can be applied to the print layer by techniques known to those skilled in the art. The polymer film may be deposited from solution or applied as a preformed film (laminated onto the print layer), or applied by any other suitable means known in the art.

[0101] When there is a transparent or opaque top layer or outer layer, the layer can have a single layer or a multilayer structure. The thickness of the protective layer is generally in the range of about 1 micron to about 125 microns, about 12.5 microns to about 125 microns, and in one embodiment about 25 microns to about 75 microns. Examples of top layers are described in U.S. Pat. No. 6,106,982 (Mientus et al.), which is incorporated herein by reference.

[0102] The facing or outer layer may comprise polyolefins, thermoplastic polymers of ethylene or propylene, polyesters, polyurethanes, polyacrylic acids, polymethacrylic acids, epoxy resins, vinyl acetate homopolymers, copolymers or terpolymers, ionomers, and mixtures thereof.

[0103] The transparent top layer or outer layer may contain ultraviolet light absorbers and / or other light stabilizers. Suitable ultraviolet light absorbers include those available from BASF under the trade names "Tinuvin" and "Chimassorb", such as Tinuvin 111, Tinuvin 123, Tinuvin 622, Tinuvin 770, Tinuvin 783, Chimassorb 119, and Chimassorb 944. The concentration of the ultraviolet light absorber and / or light stabilizer is up to about 2.5% by weight of the transparent protective layer, and in one embodiment is about 0.05% to about 1% by weight. However, in some embodiments, the transparent top layer or outer layer does not contain ultraviolet light absorbers or stabilizers.

[0104] The transparent top or outer layer may contain an antioxidant.Any antioxidant useful in making thermoplastic films may be used.

[0105] According to one embodiment, an exemplary label includes a transparent recyclable shrinkable PET film having an optional antistatic coating, high TD shrinkage, low MD shrinkage, very low shrink force, and a gentle shrinkage curve. According to one embodiment, the label of the present disclosure can meet certain industry standards, including the Association of Plastic Recyclers (APR)'s Key Guidance Protocol for Transparent PET Articles with Labels and Caps (PET-CG-02), etc., which can be considered that the standard recognizes that the film can be fully recycled with the container or bottle. In some embodiments, the label of the present disclosure is recyclable according to the "Assessment of the Near Infrared (NIR) Sorting Potential of Complete Plastic Articles (SORT-B-01)", "Assessment of the Sorting Potential of Plastic Articles Utilizing Metal, Metallized or Metal Printed Components (SORT-B-03)" or both standards. That is, according to one embodiment, the label of the present disclosure is fully recyclable. For example, the label can include ink that can be washed off during typical PET recycling washing (alkali washing), and the polymer used in the label is preferably transparent (preferably transparent PET). According to one embodiment, the label contains no or substantially no ink that cannot be washed off in an alkaline wash. According to one embodiment, the label contains no or substantially no colored plastic (including white plastic) that cannot be recycled.

[0106] High opacity coating composition

[0107] According to one embodiment, the label includes a high opacity layer formed from a high opacity coating composition. In some embodiments using a transparent shrink film, it may be useful for the disclosed articles to include an optional high opacity layer on the article or on a layer applied to the transparent shrink film. The high opacity layer can be applied by applying the high opacity coating composition to one or more layers of the label.

[0108] Useful high opacity coating compositions can include aqueous or non-aqueous ink compositions. In some embodiments, the high opacity coating compositions include white pigments. Examples of useful white pigments include, for example, titanium dioxide (TiO2), precipitated calcium carbonate (PCC), aluminum silicate, aluminum oxide, mica-based pigments coated with a thin layer of white pigment (e.g., TiO2), and combinations thereof.

[0109] In some embodiments, the high opacity coating composition may include white pigment, anionic surfactant, latex particles and the balance of water. In other cases, the high opacity coating composition may include additives such as fluorescent whitening agents, biocides, additional surfactants, cosolvents and / or wetting agents.

[0110] Useful high opacity coating compositions can include, for example, compositions formulated for use as rotogravure inks (eg, rotogravure solvent-based inks), flexographic inks, lithographic inks, or digital printing inks (eg, inkjet, nanographic printing).

[0111] The high opacity coating composition can be placed on the shrink film using any method known in the art, including but not limited to gravure printing (e.g., rotary gravure printing), flexographic printing and lithographic printing (e.g., offset lithography), plateless printing (e.g., digital printing), post-printing application, and screen printing, etc. Gravure printing is the transfer of liquid ink from a metal image carrier directly to a substrate. The image is below the surface of the image carrier substrate. Flexographic printing is the transfer of liquid ink directly to a substrate, usually from a photopolymer image carrier, although other image carriers exist. The image is raised on the surface of the image carrier substrate. Offset lithography is the indirect transfer of paste ink from a rubber "blanket" that serves as an intermediary between the substrate and the thin lithographic metal image carrier to a substrate. Some examples of plateless printing include liquid toner electrophotography, dry toner electrophotography, on-demand inkjet, continuous inkjet, or NANOGRAPHY TM .

[0112] In embodiments where the high opacity coating composition is applied to a shrink film or a layer on a shrink film by rotogravure coating or rotogravure printing, the high opacity coating composition can have a viscosity of, for example, 16 seconds to 40 seconds, 16 seconds to 25 seconds, or 19 seconds to 24 seconds as measured using a No. 2 Zahn cup.

[0113] In the embodiment where the high opacity coating composition is applied to the layer on the shrink film or the shrink film by gravure coating or rotogravure coating, one or more rotogravure printing rollers can be used to apply the high opacity coating composition. The roller can be adjusted to provide a desired amount of coating composition on the surface of the shrink film or the layer. The roller can have a unit volume of 1.0 BCM or more, 5 BCM or more, 10 BCM or more, or 15 BCM or more. The unit volume can be 2 BCM or less, 25 BCM or less, or 20 BCM or less. For example, the unit volume can be in the range of 1.0 BCM to 30.0 BCM or 5 BCM to 25 BCM. The roller can have a unit width value of 25 microns or more, 50 microns or more, or 100 microns or more. The roller can have a unit width value of 300 microns or less, 250 microns or less, or 200 microns or less. The unit width value can be, for example, in the range of 25 microns to 300 microns. The roller may have a channel width of 1 micron or more, 5 microns or more, 10 microns or more, 20 microns or more, or 30 microns or more. The channel width may be 75 microns or less, or 50 microns or less. The channel width may be in the range of 1 micron to 75 microns. The roller may have a wire mesh value of 25LPI or more, 50LPI or more, 100LPI or more, 150LPI or more, or 200LPI or more. The wire mesh value may be 400LPI or less, 350LPI or less, 300 or less, 250 or less, or 200 or less. The wire mesh value may be in the range of 25LPI to 400LPI. According to some exemplary embodiments, the desired dry coating weight may be 0.5ppr or more, 1ppr or more, 5ppr or more, 10ppr or more, or 15ppr or more. The desired dry coating weight may be 25ppr or less, 20ppr or less, or 15ppr or less. Desired dry coating weights may range from 0.5 ppr to 25 ppr.

[0114] Applying the high opacity coating composition to a shrink film or a layer on a shrink film forms a high opacity layer. The high opacity layer need not be constant, continuous or complete across the shrink film. In some embodiments, the high opacity layer forms a pattern of discrete dots of ink. In other embodiments, the high opacity layer forms a continuous layer of ink.

[0115] Light blocking layer

[0116] According to one embodiment, the label includes a layer of light-blocking material, such as light-blocking ink. The light-blocking material can be applied to the shrink film or to a layer applied to the shrink film, such as applied to the high opacity layer mentioned above. The light-blocking material can be applied in the form of a light-blocking composition comprising one or more light-blocking components.

[0117] According to one embodiment, the label comprising a light-blocking layer blocks at least 80%, at least 90%, at least 95%, at least 96%, at least 98%, at least 99%, or even almost 100% or 100% of incident light having a wavelength of 200 nanometers to 900 nanometers. According to one embodiment, the label comprising a light-blocking layer blocks at least 95%, at least 96%, at least 98%, at least 99%, at least 99.5%, approximately 100% or 100% of incident light having a wavelength of 220 nanometers to 800 nanometers. According to one embodiment, the label comprising a light-blocking layer blocks at least 98%, at least 99%, at least 99.5%, approximately 100% or 100% of incident light having a wavelength of 220 nanometers to 750 nanometers. According to one embodiment, the label comprising a light-blocking layer blocks at least 99%, at least 99.5%, approximately 100% or 100% of incident light having a wavelength of 220 nanometers to 600 nanometers. According to one embodiment, the label comprising a light-blocking layer blocks at least 99%, at least 99.5%, approximately 100%, or 100% of incident light having a wavelength of 220 nanometers to 500 nanometers. According to one embodiment, the label comprising a light-blocking layer blocks at least 99%, at least 99.5%, approximately 100%, or 100% of incident light having a wavelength of 220 nanometers to 450 nanometers. The amount of light blocked by the label can be measured using a UV-visible spectrophotometer, such as the Shimadzu UV-2600i model.

[0118] According to one embodiment, the label includes a light-blocking layer containing one or more light-blocking components. In certain embodiments, the light-blocking component includes one or more metals. In certain embodiments, available light-blocking components may include pigments encapsulated with metals or metal-containing compounds. Examples of light-blocking components include, but are not limited to, organic and inorganic pigments designed for solvent printing or water-based printing, such as metallic pigments. The pigment may be encapsulated or non-encapsulated. Available metallic pigments may, for example, include zinc, copper, silver, aluminum, and alloys and combinations thereof. In other embodiments, the light-blocking component includes titanium dioxide and related fillers, carbon black, mica, reflective pigments, and other polymers and minerals capable of blocking light.

[0119] According to one embodiment, the light-blocking component is a granular material. The particles of the light-blocking component may have a particle size of 0.1 micron or more, 0.5 micron or more, 1 micron or more, 2 microns or more, 3 microns or more, 4 microns or more, or 5 microns or more. The particle size of the particles of the light-blocking component may be 100 microns or less, 50 microns or less, 25 microns or less, 15 microns or less, 12 microns or less, 10 microns or less, 8 microns or less, 7 microns or less, or 6 microns or less. In some embodiments, the particle size of the light-blocking component is in the range of 0.1 micron to 100 microns, 1 micron to 50 microns, or 2 microns to 25 microns. The particle size here refers to the average particle size measured by laser diffraction.

[0120] Useful light-blocking coating compositions can include, for example, compositions formulated for use as rotogravure inks (eg, rotogravure solvent-based inks), flexographic inks, lithographic inks, or digital printing inks (eg, inkjet, nanographic printing).

[0121] In addition to the light-blocking components, the light-blocking composition may also contain solvents (such as alcohols, esters, ketones or hydrocarbon mixtures), resins (such as nitrocellulose, polyamide, vinyl or acrylic), or additives (such as waxes, plasticizers, surfactants, corrosion inhibitors or cross-linking agents) to adjust the properties of the composition.

[0122] The amount of the light-blocking component in the light-blocking composition can be 3.0 weight % or more, 5.0 weight % or more, or 10 weight % or more. The amount of the light-blocking component in the light-blocking composition can be 50.0 weight % or less, 40 weight % or less, 30 weight % or less, or 25 weight % or less. The amount of the light-blocking component in the light-blocking composition can be 3.0 weight % to 50 weight %, 5.0 weight % to 40 weight %, or 10 weight % to 25 weight %. The amount of the light-blocking component on the label can vary according to the required light-blocking amount and the specific light-blocking component used. In certain embodiments, the light-blocking component can be present on the label in an amount of 0.1 ppr to 10 ppr, 0.2 ppr to 5 ppr, or 0.3 ppr to 3 ppr.

[0123] The light-blocking coating composition can be applied to the shrink film (or a layer on the shrink film) using any method known in the art, including, for example, but not limited to gravure printing (e.g., rotary gravure printing), flexographic printing and lithographic printing (e.g., offset lithography), plateless printing (e.g., digital printing), post-printing application, and screen printing. Gravure printing is the transfer of liquid ink from a metal image carrier directly to a substrate. The image is below the surface of the image carrier substrate. Flexographic printing is the transfer of liquid ink directly to a substrate, usually from a photopolymer image carrier, although other image carriers exist. The image is raised on the surface of the image carrier substrate. Offset lithography is the indirect transfer of paste ink from a rubber "blanket" that serves as an intermediary between the substrate and the thin lithographic metal image carrier to a substrate. Some examples of plateless printing include liquid toner electrophotography, dry toner electrophotography, on-demand inkjet, continuous inkjet, or NANOGRAPHY TM .

[0124] In embodiments where the light-blocking coating composition is applied to a shrink film or a layer on a shrink film by rotogravure coating or printing, the light-blocking coating composition can have a viscosity of 16 seconds or more, 17 seconds or more, 18 seconds or more, or 19 seconds or more measured using a No. 2 Zahn cup. The viscosity can be 40 seconds or less, 25 seconds or less, or 24 seconds or less. For example, the viscosity can range from 16 seconds to 40 seconds, 15 seconds to 25 seconds, or even 19 seconds to 24 seconds.

[0125] The light-blocking composition can be applied to the label at an appropriate rate to produce the required light-blocking properties. When using gravure coating or rotary gravure coating, the amount of the composition used can be controlled by adjusting the engraving specifications of the gravure printing cylinder. The cylinder can have a unit volume of 1.0 BCM or more, 5 BCM or more, 10 BCM or more, or 15 BCM or more. The unit volume can be 2 BCM or less, 25 BCM or less, or 20 BCM or less. For example, the unit volume can be in the range of 1.0 BCM to 30.0 BCM or 5 BCM to 25 BCM. The cylinder can have a unit width value of 25 microns or more, 50 microns or more, or 100 microns or more. The cylinder can have a unit width value of 300 microns or less, 250 microns or less, or 200 microns or less. The unit width value can be, for example, in the range of 25 microns to 300 microns. The roller may have a channel width of 1 micron or more, 5 microns or more, 10 microns or more, 20 microns or more, or 30 microns or more. The channel width may be 75 microns or less, or 50 microns or less. The channel width may be in the range of 1 micron to 75 microns. The roller may have a wire mesh value of 25 LPI or more, 50 LPI or more, 100 LPI or more, 150 LPI or more, or 200 LPI or more. The wire mesh value may be 400 LPI or less, 350 LPI or less, 300 or less, 250 or less, or 200 or less. The wire mesh value may be in the range of 25 LPI to 400 LPI. According to some exemplary embodiments, the desired dry coating weight may be 0.1 ppr or more, 0.2 ppr or more, 0.3 ppr or more, 0.4 ppr or more, 0.5 ppr or more, 1 ppr or more, 5 ppr or more, 10 ppr or more, or 15 ppr or more. The desired dry coating weight may be 25 ppr or less, 20 ppr or less, or 15 ppr or less. The desired dry coating weight may be in the range of 0.1 ppr to 25 ppr, 0.4 ppr to 15 ppr, or 0.5 ppr to 10 ppr.

[0126] In some embodiments, the light-blocking coating composition can be applied to the shrink film or the layer on the shrink film by rotogravure coating or printing using a single (1) rotogravure printing cylinder with a line screen of 25 LPI to 400 LPI. In some embodiments, the light-blocking coating composition can be applied to the shrink film or the layer on the shrink film by rotogravure coating using a single (1) rotogravure printing cylinder with a line screen of 120 LPI or using two (2) rotogravure printing cylinders with a line screen of 200 LPI. The resulting dry coating weight can be in the range of 0.5 ppr to 10 ppr.

[0127] Applying the light-blocking coating composition to a shrink film or a layer on a shrink film forms a light-blocking layer. The light-blocking layer need not be constant, continuous or complete across the shrink film. In some embodiments, the high opacity layer forms a pattern of discrete dots of light-blocking composition. In other embodiments, the high opacity layer forms a continuous layer of light-blocking composition.

[0128] Marker layer

[0129] The disclosed labels may also include a marking layer applied to a layer on the label or on the shrink film, for example including the high opacity layer discussed above. The marking layer may be applied by applying one or more image forming composition layers or applying one or more partial image forming composition layers.

[0130] Useful image forming compositions can include, for example, compositions formulated for use as rotogravure inks (e.g., rotogravure solvent-based inks), flexographic inks, lithographic inks, or digital printing inks (e.g., inkjet, nanographic printing). Almost any combination of inks or ink compositions that can be used to form markings (e.g., images and associated text for forming product labels) can be used to form the marking layer disclosed herein.

[0131] There is no particular limitation on suitable ingredients of the image forming composition. Some examples of suitable ingredients that can be used in the image forming composition are disclosed below.

[0132] In some embodiments, the image forming composition comprises a solvent, such as an organic solvent or water, or a combination thereof. The amount of solvent in the composition can be adjusted to provide a desired color density and viscosity (eg, measured using a calibrated No. 2 Zahn cup).

[0133] The image forming composition may include any suitable inorganic or organic pigment. Examples of inorganic pigments include pigments such as titanium dioxide, chrome yellow, molybdenum orange, iron blue, cadmium yellow, chrome green, ultramarine, calcium carbonate, magnesium carbonate, silica aerogel or kaolin. Examples of organic pigments include, for example, Hansa yellow, lamp black, phthalocyanine, red lake C, benzidine yellow, fluorescent pink, channel black or rhodamine. The typical amount of the pigment in the ink composition for gravure printing can be in the range of 1% by weight to 20% by weight.

[0134] The image forming composition may include a binder resin such as polyamide, nitrocellulose, shellac, a vinyl polymer, a rosin ester, or an acrylic polymer.

[0135] The image forming composition can be placed on the shrink film (or on a layer on the shrink film) using any method known in the art, including, for example, but not limited to gravure printing (e.g., rotary gravure printing), flexographic printing and lithographic printing (e.g., offset lithography), plateless printing (e.g., digital printing), post-printing application, and screen printing. Gravure printing is the transfer of liquid ink from a metal image carrier directly to a substrate. The image is below the surface of the image carrier substrate. Flexographic printing is the transfer of liquid ink directly to a substrate, usually from a photopolymer image carrier, although other image carriers exist. The image is raised on the surface of the image carrier substrate. Offset lithography is the indirect transfer of a paste ink from a rubber "blanket" that serves as an intermediary between the substrate and the thin lithographic metal image carrier to a substrate. Some examples of plateless printing include liquid toner electrophotography, dry toner electrophotography, on-demand inkjet, continuous inkjet, or NANOGRAPHY TM .

[0136] Applying the image forming composition to a shrink film or a layer on a shrink film forms a marking layer. The marking layer need not be constant, continuous or complete across the shrink film.

[0137] The marking layer can be an ink or a graphic layer, and the marking layer can be a monochrome or multi-color printing layer, depending on the information printed and / or the predetermined pattern design. These information include variable imprint data, such as serial numbers, bar codes, trademarks, etc. The thickness of the marking layer is generally in the range of about 0.5 to about 10 microns, in one embodiment in the range of about 1 to about 5 microns, and in another embodiment is about 3 microns. The ink used in the marking layer can include commercially available water-based, solvent-based, oil-based or energy-curable inks. Examples of commercially available inks include INXFlexContour (a product of INX, considered to be an energy-curable ink for shrink sleeve applications), Genesis GS (a product of INX, considered to be a gravure solvent-based ink for shrink sleeve and roll-fed applications), FlexiTechShrink-U (a product of Flint Group, considered to be a flexographic solvent-based ink for shrink sleeve applications) or PluriTech Shrink-U (a product of Flint Group, considered to be a gravure solvent-based ink for shrink sleeve applications).

[0138] In one embodiment, the marking layer may comprise polyester / vinyl ink, polyamide ink, acrylic ink and / or polyester ink. The marking layer may be formed in a conventional manner, for example, by applying an ink composition comprising a resin of the above type, a suitable pigment or dye, and one or more suitable volatile solvents to one or more desired areas on a shrink film or a layer on a shrink film by rotogravure, flexographic or lithographic processes, etc. After applying the marking forming composition, the volatile solvent component of the ink composition evaporates, leaving only the non-volatile ink component to form the marking layer.

[0139] The total amount of ink on the label depends on the graphic (marking layer), the background (e.g., white) layer, and the light-blocking layer. The total amount of ink can be 0.5 ppr or more, 1 ppr or more, 5 ppr or more, 10 ppr or more, or 15 ppr or more. The total amount of ink can be 30 ppr or less, 25 ppr or less, 20 ppr or less, or 15 ppr or less. The total amount of ink can be in the range of 0.5 ppr to 30 ppr.

[0140] Products and containers

[0141] Figure 1A An article 10 (e.g., a bottle or other container) is shown having a heat shrink label 100 applied to an outer surface thereof. The heat shrink label 100 includes a heat shrink film 120, a marking layer 125 (e.g., a graphic) is disposed on one surface of the heat shrink film 120, and the opposite surface includes a high opacity layer 110 and a light blocking layer 115 disposed on the high opacity layer 110. In this embodiment, the light blocking layer 115 is closest to the article to which the heat shrink label 100 is applied.

[0142] Figure 1B An article 10 (e.g., a bottle or other container) is shown having a heat shrink label 101 applied to an outer surface thereof. The heat shrink label 101 includes a heat shrink film 120, a light blocking layer 115 is disposed on one surface of the heat shrink film 120, and the opposite surface has a high opacity layer 110. A marking layer 125 is disposed on the surface of the high opacity layer 110 opposite to the heat shrink film 120. In this embodiment, the light blocking layer 115 is closest to the article 10 to which the heat shrink label 101 is applied.

[0143] Figure 1CAn article 10 (e.g., a bottle or other container) is shown, which has a heat shrink label 102 applied to its outer surface. The heat shrink label 102 includes a heat shrink film 120, a marking layer 125 is provided on the surface of the heat shrink film 120, a high opacity layer 110 is provided on the surface of the marking layer 125, and a light blocking layer 115 is provided on the high opacity layer 110. In this embodiment, the light blocking layer 115 is closest to the article 10 to which the heat shrink label 102 is applied.

[0144] Figure 1D An article 10 (e.g., a bottle or other container) is shown having a heat shrink label 103 applied to an outer surface thereof. The heat shrink label 103 includes a heat shrink film 120 having a light-blocking layer 115 disposed on one surface of the heat shrink film 120 and an indicia layer 125 disposed on an opposite surface. In this embodiment, the light-blocking layer 115 is closest to the article 10 to which the heat shrink label 103 is applied. Such an embodiment may be useful, for example, where a dark or black background is acceptable or desirable for the printed label.

[0145] Figure 1E An article 10 (e.g., a bottle or other container) is shown, which has a heat shrink label 104 applied to its outer surface. The heat shrink label 104 includes a heat shrink film 120, a marking layer 125 is provided on the surface of the heat shrink film 120, and a light blocking layer 115 is provided on the surface of the marking layer 125. In this embodiment, the light blocking layer 115 is closest to the article 10 to which the heat shrink label 104 is applied.

[0146] It should also be noted that additional layers not shown in these embodiments (including tie layers, adhesive layers, primer layers, etc.) may optionally be included between or adjacent to any of the layers shown.

[0147] The articles or containers to which the labels are applied may be provided in a variety of forms or shapes. Non-limiting examples of suitable articles include containers with and without closures, such as bottles, cans, tubes, trays, lids, toys, utensils, etc. Figure 2An exemplary article 1 is shown in FIG. The article 1 includes a container 10 (e.g., a bottle) defining an outer surface 11. The recyclable shrink label 100' of an embodiment of the present disclosure is arranged on the outer surface 11. The first side of the recyclable shrink label 100' faces the container 10, and the second side 150 faces outward. The article or container can be made of any polymer (e.g., a conventional polymer or a biopolymer), glass, or metal (e.g., aluminum). Examples of suitable polymeric materials include high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyethylene terephthalate (PET), polypropylene (PP), polylactic acid (PLA), polyvinyl chloride, polycarbonate, nylon, fluorinated ethylene propylene, polystyrene, and the like. The article or container can be made of recyclable materials. The article or container can be made of the same or similar polymer as the label, such as PET. The article or container can be manufactured by various methods known in the art, such as blow molding, injection molding, thermoforming, rotational molding, and the like.

[0148] Available containers include, for example, bottles with closures, tubes with closures, cans, etc. In some embodiments, available beverage containers may include one or more recyclable synthetic pigments and / or resins. Preferably, the container can be processed in an existing recycling stream, such as a mechanical PET recycling stream. Non-limiting examples of suitable pigments and / or resins include, but are not limited to, high melting point PET powder; PET comonomers; reactants or byproducts of PET polymerization; polyethylene naphthalate (PEN); terephthalic acid (TPA or PTA); bis(hydroxyethyl) terephthalate (BHET); dimethyl terephthalate (DMT); dimethyl 2,6-naphthalate (NDC); and isophthalic acid (IPA).

[0149] The container or article may have a transparent appearance. In one embodiment, the container or article has a translucent appearance. The translucent appearance can be achieved, for example, by treating the transparent container or article, adding some ingredients (such as dyes and pearlescent agents) to the base polymer, using polypropylene and / or polyethylene mixed with a clarifying agent. The treatment includes, for example, spraying, sandblasting, and mold surface treatment.

[0150] In one embodiment, the continuous roll labels of the embodiments of the present disclosure can be applied to the articles or containers in an automated labeling line process. The automated labeling line process can have a line speed of at least 10 units per minute, at least 25 units per minute, at least 50 units per minute, at least 100 units per minute, or at least 250 units per minute. Although there is no desired upper limit, in practice, the automated labeling line process can have a line speed of up to 2000 units per minute, such as no more than 500, no more than 600, no more than 700, no more than 800, no more than 900, or no more than 1000 units per minute.

[0151] The invention is defined in the claims. However, a non-exhaustive list of non-limiting exemplary aspects is provided below. Any one or more of the features of these aspects may be combined with any one or more features of another example, embodiment or aspect described herein.

[0152] According to an exemplary embodiment, a transparent shrink film (e.g., a transparent PET shrink film) having a thickness of, for example, 15 microns to 100 microns, 20 microns to 80 microns, or 25 meters to 70 meters is formed from a very wide master roll. The process provides the correct width for the material size requirements of the production order. Typically, the printed art is repeated over the width of the film to maximize the total number of labels printed on each roll. The slitting step allows the film to be converted to the correct width for the seaming process. The shrink film can be printed using a rotogravure press, for example, with solvent-based inks, for example. Light-blocking inks can be printed on either side of the film at one or more printing stations. A high opacity coating can also be optionally applied to either side of the film together with the light-blocking layer to provide a white opaque background for the art or graphics of the label set in the marking layer. When using a transparent film, the graphics can be printed directly on the film, followed by applying a high opacity layer (e.g., white ink), and then applying a light-blocking layer. The graphics are visible through the transparent film and are protected by the film. Alternatively, the graphics can be printed on a white opaque background. When printing graphics using a rotogravure press, typically, the graphics are repeatedly printed on a web of film, and then the web is slit into individual label rolls. Any number of colors can be printed, each with its own printing cylinder and ink station to apply different inks, colors and / or coatings. The ink is then blown dry using a hot air convection blower at each printing station. For rotogravure printing, a line screen of no less than 25 LPI to a maximum of 300 LPI can be used. Viscosity readings in the range of 16-28 measured using a No. 2 Zahn cup are typical viscosities of the ink. The light-blocking layer can be a solvent-based or water-based composition and diluted with known solvents and / or additives to achieve the viscosity required for a specific printing process. In some embodiments, at commercial press speeds of 100 meters / minute to 300 meters / minute, multiple engravings can be performed for the light-blocking layer and the high opacity layer (if used) to provide the desired ink coverage. All layers, including the high opacity layer and the light-blocking layer, can be shrunk together with the shrink film to ensure proper adhesion and color density after undergoing the shrinking process. These layers are preferably capable of passing a tape test using a tape of the type recommended for the ink system, or a Sutherland Ink Rub Tester test using a 4 lb. rub block for over 100 rubs, or both. The light-blocking layer is typically designed to have a low dynamic coefficient of friction (COF), such as less than 0.22.

[0153] The printed film can then be converted into a continuous tube from a flat roll, and a solvent is applied on one side of the edge of the film. The seaming machine can overlap the solvent edge side of the film on the edge that is not coated with solvent, so that both sides are chemically combined, thereby forming a continuous film tube that is wound into a large roll. For example, the standard seam speed can be within the range of 200 meters per minute to 500 meters per minute. Then, the label coil after the seam / into a tube can be wound into a finished roll of a smaller length, for example, so as to be transported to a client and applied to a predetermined container. The label comprising a light-blocking layer can, for example, block at least 80%, at least 90%, at least 95%, at least 96%, at least 98%, at least 99% or even almost 100% or 100% of the incident light with a wavelength of 200 nanometers to 900 nanometers.

[0154] According to one embodiment, a method for recycling an article includes determining the type of material (e.g., type of plastic) used to make a container and a recyclable shrink label, introducing the article into a corresponding recycling stream, and washing the article to remove ink and pigment from the recyclable shrink label. In some cases, the article and label contain PET or are made of PET and can be identified as PET and introduced into a PET recycling stream. In other cases, the article and label can contain another resin or be made of another resin and be introduced into a corresponding recycling stream. In some preferred embodiments, the label applied to the article contains the same resin as the article or is made of the resin. The washed article can be transparent and not contaminated or substantially contaminated by light-blocking components. The article can be washed in an alkaline bath. The article can be cut into pieces before washing. According to one embodiment, during the recycling process, ink and coating are cleanly separated from the heat shrink film, thereby allowing pure resin to be recovered and processed into reusable resin.

[0155] Exemplary Embodiments

[0156] Embodiment 1 is a recyclable shrink label, which includes a heat shrink film having a first surface and a second surface opposite to the first surface, optionally, wherein the heat shrink film has a thickness of 15 to 100 microns or 30 to 80 microns; and a light blocking layer arranged adjacent to the first surface and including a light blocking component, the light blocking layer being configured to block at least 80% of incident light having a wavelength in the range of 200 to 900 nanometers.

[0157] Embodiment 2 is the recyclable shrink label of embodiment 1, the recyclable shrink label further comprising a marking layer, optionally, wherein the marking layer is arranged on the first surface. The marking layer may be adjacent to the first surface. The marking layer may be adjacent to the light blocking layer. The marking layer may be arranged between the first surface and another layer (e.g., a high opacity layer).

[0158] Embodiment 3 is the recyclable shrink label of embodiment 1, further comprising a high opacity layer, the high opacity layer optionally comprising a white pigment.

[0159] Embodiment 4 is the recyclable shrink label of embodiment 3, wherein the high opacity layer is arranged between the marking layer and the light blocking layer. The high opacity layer can be adjacent to the marking layer. The high opacity layer can be adjacent to the light blocking layer.

[0160] Embodiment 5 is the recyclable shrink label of any one of embodiments 1 to 4, wherein the heat shrink film comprises polyester, polyolefin, or a combination thereof.

[0161] Embodiment 6 is a recyclable shrink label of any one of embodiments 1 to 5, wherein the heat shrinkable film comprises polyethylene terephthalate (PET), modified polyethylene terephthalate (PETG or PET-G), polyvinyl chloride (PVC), polystyrene or oriented polystyrene (OPS), polylactic acid (PLA), polypropylene (PP), polyethylene (PE), or a combination thereof. The heat shrinkable film may be composed of polyethylene terephthalate (PET), modified polyethylene terephthalate (PETG or PET-G), polyvinyl chloride (PVC), polystyrene or oriented polystyrene (OPS), polylactic acid (PLA), polypropylene (PP), polyethylene (PE), or a combination thereof. The heat shrinkable film may be composed of only one of polyethylene terephthalate (PET), modified polyethylene terephthalate (PETG or PET-G), polyvinyl chloride (PVC), polystyrene or oriented polystyrene (OPS), polylactic acid (PLA), polypropylene (PP), polyethylene (PE), or a combination thereof. The heat shrinkable film may be composed of polyethylene terephthalate (PET).

[0162] Embodiment 7 is the recyclable shrink label of any one of embodiments 1 to 6, wherein the heat shrink film comprises a seam.

[0163] Embodiment 8 is the recyclable shrink label of any one of embodiments 1 to 7, wherein the heat shrink film is in the form of a sleeve or a tube. The heat shrink film can be configured to be sleeved on a bottle.

[0164] Embodiment 9 is the recyclable shrink label of any one of embodiments 1 to 8, wherein, when heated to 100° C., the heat shrink film retracts or shrinks by about 1% to about 90%. The heat shrink film may shrink by 1% or more, 2% or more, 5% or more, 10% or more, 20% or more, 30% or more, 40% or more, or 50% or more of the size before heating. When heated to 100° C., the heat shrink film may shrink by 90% or less, 80% or less, 75% or less, or 70% or less of the size before heating. The heat shrink film may shrink in the transverse direction.

[0165] Embodiment 10 is the recyclable shrink label of any one of embodiments 1 to 9, wherein the entire recyclable shrink label retracts or shrinks by about 1% to about 90% when heated to 100° C. The entire recyclable shrink label may shrink in a transverse direction.

[0166] Embodiment 11 is the recyclable shrink label of embodiment 1, wherein the high opacity layer comprises a pigment selected from titanium dioxide (TiO2), precipitated calcium carbonate (PCC), aluminum silicate, aluminum oxide, mica-based pigments coated with a thin layer of white pigment, or combinations thereof.

[0167] Embodiment 12 is the recyclable shrink label of any one of embodiments 1 to 11, wherein the light-blocking component comprises metal particles, and optionally, wherein the metal particles have a particle size of 0.1 micrometer to 100 micrometers.

[0168] Embodiment 13 is the recyclable shrink label of any one of embodiments 1 to 12, wherein the light-blocking component comprises zinc, aluminum, copper, silver or alloys thereof, titanium dioxide, carbon black, mica, reflective pigments, polymers capable of blocking light, minerals capable of blocking light or combinations thereof. The light-blocking component may be composed of an aluminum-based component.

[0169] Embodiment 14 is the recyclable shrink label of any one of embodiments 1 to 13, wherein the light-blocking layer is present in an amount of 0.5 ppr to 25 ppr. The light-blocking layer may have a dry coating weight of 0.1 ppr or more, 0.2 ppr or more, 0.3 ppr or more, 0.4 ppr or more, 0.5 ppr or more, 1 ppr or more, 5 ppr or more, 10 ppr or more, or 15 ppr or more. The dry coating weight may be 25 ppr or less, 20 ppr or less, or 15 ppr or less. The dry coating weight may be in the range of 0.1 ppr to 25 ppr, 0.4 ppr to 15 ppr, or 0.5 ppr to 10 ppr.

[0170] Embodiment 15 is the recyclable shrink label of any one of embodiments 1 to 14, wherein the light-blocking layer comprises 0.1 ppr to 10 ppr, 0.2 ppr to 5 ppr, or 0.3 ppr to 3 ppr of the light-blocking component.

[0171] Embodiment 16 is the recyclable shrink label of any one of embodiments 1 to 15, wherein the label comprising a light-blocking layer blocks at least 80%, at least 90%, at least 95%, at least 96%, at least 98%, at least 99%, or even almost 100% or 100% of incident light having a wavelength of 200 nanometers to 900 nanometers. The label comprising a light-blocking layer can block at least 95%, at least 96%, at least 98%, at least 99%, at least 99.5%, about 100% or 100% of incident light having a wavelength of 220 nanometers to 800 nanometers. The label comprising a light-blocking layer can block at least 98%, at least 99%, at least 99.5%, about 100% or 100% of incident light having a wavelength of 220 nanometers to 750 nanometers. The label comprising a light-blocking layer can block at least 99%, at least 99.5%, about 100% or 100% of incident light having a wavelength of 220 nanometers to 600 nanometers. The label comprising the light-blocking layer can block at least 99%, at least 99.5%, approximately 100%, or 100% of incident light having a wavelength of 220 nanometers to 500 nanometers. The label comprising the light-blocking layer can block at least 99%, at least 99.5%, approximately 100%, or 100% of incident light having a wavelength of 220 nanometers to 450 nanometers.

[0172] Embodiment 17 is an article, comprising: a container comprising an outer surface; and the recyclable shrink label of any one of embodiments 1 to 16 disposed on the container, optionally, the first surface facing the outer surface of the container.

[0173] Embodiment 18 is the article of embodiment 17, wherein the container comprises a polymer, glass, metal, or a combination thereof.

[0174] Embodiment 19 is the article of any one of embodiments 16 to 18, wherein the container comprises polyethylene terephthalate (PET), optionally wherein the container consists of polyethylene terephthalate (PET), optionally wherein the container comprises transparent polyethylene terephthalate (PET).

[0175] Embodiment 20 is the article of any one of embodiments 16 to 19, wherein the recyclable shrink label comprises polyethylene terephthalate (PET), and, optionally, wherein the polyethylene terephthalate (PET) forms an outermost layer of the recyclable shrink label.

[0176] Embodiment 21 is the article of any one of embodiments 16 to 20, wherein the container and the recyclable shrink label comprise the same material. The container and the recyclable shrink label may comprise polyethylene terephthalate (PET).

[0177] Embodiment 22 is a method for manufacturing a label for a container, the method comprising depositing a marking layer on a heat shrink film; optionally depositing a high opacity layer on the marking layer; and depositing a light-blocking composition on the marking layer, the heat shrink film or the high opacity layer, wherein the light-blocking layer comprises one or more light-blocking ingredients, and wherein the light-blocking layer is capable of blocking at least 80% of incident light having a wavelength in the range of 200 nanometers to 900 nanometers.

[0178] Embodiment 23 is a method for recycling an article, the article comprising a container defining an outer surface; and a recyclable shrink label of any one of embodiments 1 to 16 arranged on the container, optionally, the first surface facing the outer surface of the container, the method comprising determining that the container and the recyclable shrink label contain polyethylene terephthalate (PET); introducing the article into a polyethylene terephthalate (PET) recycling stream; and washing the article to remove ink and pigment from the recyclable shrink label.

[0179] Embodiment 24 is the method of embodiment 23, wherein the cleaned article is transparent and is not contaminated by light-blocking components or other pigments or inks.

[0180] Embodiment 25 is the method of embodiment 24, wherein cleaning comprises cleaning in an alkaline bath.

[0181] Embodiment 26 is the recyclable shrink label of any one of embodiments 1 to 16, further comprising an additional layer comprising an additional polymer layer, an additional marking layer, an adhesive layer, a slip coating, a protective top layer, another functional layer, or a combination thereof.

[0182] The present invention is illustrated by the following examples. It is to be understood that the particular examples, materials, amounts and procedures are to be interpreted broadly in accordance with the scope and spirit of the invention as set forth herein.

[0183] Objects and advantages of this disclosure are further illustrated by the following examples, but the particular materials and amounts of materials recited in these examples, as well as other conditions and details, should not be construed to unduly limit this disclosure.

[0184] Unless otherwise indicated, all parts, percentages, ratios, etc. in the examples and the remainder of the specification are by weight. In the following examples, these abbreviations are used: g = gram, min = minute, hr = hour, mL = milliliter, L = liter. If not otherwise indicated in the following tables, the chemicals were obtained from Sigma-Aldrich, St. Louis, Missouri, USA.

[0185] Examples

[0186] Example 1

[0187] Exemplary articles were made, as shown in Table 1A below. The light blocking ability of the samples at wavelengths of 400 nm, 500 nm, 600 nm and 700 nm was tested using a UV-Vis spectrophotometer (Shimadzu UV-2600i model). The samples were tested before shrinking. Samples 6 and 7 were also tested after shrinking. The results are shown in Table 1B.

[0188] The first and second layers are high opacity layers printed with white ink. The third layer contains white ink and, for samples 1-3, blue ink. The fourth and fifth layers are light-blocking layers. The light-blocking component is a bronze-colored metal particle.

[0189] Table 1A: Samples

[0190]

[0191] Table 1B: Light blocking percentage at different wavelengths

[0192]

[0193]

[0194] Figure 3-5 The UV-Vis spectra of the samples are shown. Figure 3 The transmittance of each sample in Table 1B is shown. Figure 4 is an enlarged view of the lower panel, showing sample 2-7. Figure 5 Shown is a comparison of Samples 6 and 7 (before shrinkage) with Sample 6 after shrinkage and Sample 7 after shrinkage.

[0195] Example 2

[0196] Samples with various color patterns were prepared to evaluate the effect of color on light blocking properties and the effect of the light blocking layer on color appearance.

[0197] The samples were prepared using APR certified recyclable 40 micron clear PET shrink sleeve film. The ink was printed onto the film using a solvent based rotogravure ink. The film was first printed using a single color (yellow, red, or reflective blue). Three layers of white ink were then overlaid over the printed color. The film was then printed using a 12 BCM (billion cubic microns per square inch, or 10 9 The light-blocking composition is applied over the white ink layer using a rotogravure printing cylinder having a printing capacity of 100 μm3 / square inch.

[0198] The light blocking ability of the samples in the wavelength range of 220 nm to 900 nm (before shrinkage) was tested using a UV-visible spectrophotometer (Shimadzu UV-2600i model). The results are shown in Table 2. The samples were also visually observed to evaluate the effect of the light blocking layer on the color appearance.

[0199] Table 2. Light blocking

[0200] Wavelength (nanometers) Yellow film Red film Blue film 220 100.0％ 100.0％ 100.0％ 300 100.0％ 100.0％ 100.0％ 400 100.0％ 100.0％ 100.0％ 500 99.8％ 99.9％ 99.9％ 600 98.6％ 99.1％ 100.0％ 700 98.3％ 98.5％ 99.9％ 800 98.2％ 98.3％ 98.6％ 900 97.9％ 98.2％ 98.3％

[0201] The observations show that inks with lower L* values ​​(darker colors on the L*a*b* scale) slightly improve light blocking at certain wavelengths (e.g., 600-700 nm). It was also observed that the light blocking composition had an effect on the visual appearance of the color. It was concluded that more saturated or more opaque colors could be used to produce the desired color effect.

[0202] Example 3

[0203] The effect of the thickness of the light-blocking layer on the light-blocking ability was evaluated. Various samples were prepared using APR certified recyclable 40 micron clear PET shrink sleeve film. The ink was printed onto the film using a solvent-based rotogravure ink. The film was first printed using three layers of white ink. Over the white ink layer, various thicknesses of the light-blocking composition were applied using a "belt" rotogravure cylinder (each printing pass had a different engraving specification), the pass having a range of BCM to 12 BCM (billion cubic micrometers per square inch, or 10 9 The light-blocking composition comprises a metal light-blocking component having a gray or silver appearance.

[0204] The light blocking ability of the samples in the wavelength range of 220 nanometers to 900 nanometers (before shrinkage) was tested with an ultraviolet-visible spectrophotometer (Shimadzu UV-2600i model). The results are shown in Table 3. The samples were also visually observed to evaluate the effect of the light blocking layer on the appearance of the white layer printed before it. It was observed that the thickness of the light blocking layer was inversely proportional to the brightness of the white. As the thickness of the light blocking layer increased, the brightness of the white layer decreased. As the thickness of the light blocking layer decreased, the brightness of the white layer increased.

[0205] Table 3. Light blocking

[0206]

[0207] Example 4

[0208] The light blocking properties of labels prepared according to the present disclosure were compared to commercially available light blocking labels.

[0209] Similar to Example 3, sample labels were prepared by engraving a "belt-shaped" rotogravure cylinder with channels having a volume of 12 BCM, 10 BCM, 8 BCM, and 6 BCM to apply the light-blocking layer. The comparative samples were two (2) different commercially available white PET films, each printed with black ink on one side by a rotogravure cylinder having a volume of 10 BCM. The comparative samples were not recyclable.

[0210] The samples were tested as described in Example 3. The results are shown in Table 4.

[0211] Table 4. Light blocking

[0212]

[0213]

[0214] The observation results show that when the light-blocking layer is thicker, the label of the present disclosure provides light-blocking properties comparable to those of commercially available labels. When the light-blocking layer is not too thick, the light-blocking properties are reduced, as shown in Example 3.

[0215] It was observed through visual comparison that the labels of the present disclosure exhibited better brightness characteristics.

[0216] Example 5

[0217] The light blocking performance of labels prepared according to the present disclosure was compared to comparative labels used for light blocking and available on the market.

[0218] Sample labels were prepared using APR certified recyclable 40 micron clear PET shrink sleeve film. The ink was printed onto the film using solvent based rotogravure inks. The marking layer (four different color inks) was first printed on the film. The printed marking layer was then covered with three layers of white ink. The printed marking layer was then covered with a volume of 12 BCM (billion cubic microns per square inch, or 10 9 The light-blocking composition is applied over the white ink layer using a rotogravure printing cylinder having a printing capacity of 100 μm3 / square inch.

[0219] The comparative samples (Comparative Sample 3 and Comparative Sample 4) are two (2) different printed labels currently used for products that need to block light to protect their contents. Comparative Sample 3 is printed on a white film with almost the same graphics as the sample label, and is printed black on the inside to help block light. Comparative Sample 4 is printed on a white film with a different graphics than the sample label or Comparative Sample 3, and is printed black on the inside to help block light. The comparative samples are not recyclable.

[0220] The samples were tested as described in Example 3. The light blocking results are shown in Table 5 below.

[0221] Table 5. Light blocking

[0222] Wavelength (nanometers) Sample Label Comparative Example 3 Comparative Example 4 220 100.0％ 100.0％ 100.0％ 300 100.0％ 100.0％ 100.0％ 400 99.9％ 99.8％ 99.8％ 500 99.3％ 99.7％ 99.7％ 600 99.1％ 99.5％ 99.5％ 700 98.9％ 99.3％ 99.3％ 800 98.8％ 99.1％ 99.1％ 900 98.7％ 98.9％ 98.9％

[0223] It was observed that the labels of the present disclosure provided light blocking properties comparable to commercially available labels.

[0224] It was observed through visual comparison that the label of the present disclosure exhibited better brightness characteristics, and the color of the marking layer appeared more vivid.

[0225] Example 6

[0226] The ability of typical recycling equipment to properly sort the disclosed labeled bottles was tested for compatibility with APR sorting requirements. The samples were tested in accordance with APR document SORT-B-03, Evaluation of the Sorting Potential of Plastic Articles Utilizing Metal, Metallized, or Metal Printed Components, dated May 15, 2018. Further guidance can be found in APR documents PET-CG-02, Key Guidance Protocol for Transparent PET Articles with Labels and Closures, and PET-B-02, Benchmark Evaluation of Transparent PET Articles with Labels and Closures.

[0227] Labels with 12 BCM light blocking layer were prepared as described in Example 2. The labels were attached to clear PET bottles. Bottles with labels were tested in vertical and horizontal orientations on the Eriez Xtreme test line. Before the test began, the candidate article was compressed. Determine if the article is ferrous. Ferrous articles were tested using a plate magnet. The article was then passed through a tunnel metal detector in vertical and horizontal orientations and the spherical equivalent of the sample was calculated. A sphere size of 0-2 mm indicates a recyclable sample.

[0228] The sample was found to exhibit a sphere size of 0.5 mm in the longitudinal direction and 0.6 mm in the transverse direction.

[0229] The bottle was also passed through an eddy current sorter and an NIR sorter for identifying PET products. The bottle was identified as PET by the NIR sorter. The bottle was also not caught by the eddy current sorter. In other words, the bottle passed the recycling standards for plastic bottles (such as PET).

[0230] The complete disclosures of all patents, patent applications and announcements cited in this article and electronically available materials are incorporated herein by reference. If there is any inconsistency between the disclosure of this application and the disclosure of any file incorporated herein by reference, the disclosure of this application shall prevail. The foregoing detailed description and examples are provided only for the purpose of clear understanding. These contents should not be construed as constituting any unnecessary limitations. The present invention is not limited to the exact details shown and described, and changes that are obvious to those skilled in the art should be included in the present invention defined by the claims.

Claims

1. A recyclable shrink label, comprising: A heat shrinkable film, wherein the heat shrinkable film comprises polyester, wherein the polyester is selected from polyethylene terephthalate (PET), modified polyethylene terephthalate (PETG or PET-G), polyvinyl chloride (PVC), polystyrene or oriented polystyrene (OPS), polylactic acid, copolymers and mixtures thereof, or the heat shrinkable film comprises polyolefin, wherein the polyolefin is selected from polypropylene (PP), polyethylene (PE) and copolymers and mixtures thereof, and the heat shrinkable film has a thickness of 30 μm to 100 μm; a light-blocking layer, the light-blocking layer being arranged on the heat-shrinkable film or on an intermediate layer arranged on the heat-shrinkable film, and comprising a light-blocking component, the light-blocking layer being configured such that the recyclable shrink label blocks at least 80% of incident light having a wavelength in a range of 250 nanometers to 900 nanometers; wherein the light-blocking component comprises particles, the particles comprising at least one of the following: metals, metal oxides, reflective pigments, carbon black, mica, and combinations thereof; wherein the dynamic coefficient of friction (COF) of the light-blocking layer is less than 0.22; and High opacity layer; The shrink label is constructed such that no ink remains on the shrink label after an alkaline wash cycle of a recycling process.

2. The recyclable shrink label according to claim 1, wherein: The heat shrinkable film includes PETG.

3. The recyclable shrink label according to claim 1, wherein: The heat shrinkable film includes PET.

4. The recyclable shrink label according to claim 1, further comprising a marking layer.

5. The recyclable shrink label according to claim 1, wherein: The high opacity layer comprises a pigment selected from the group consisting of titanium dioxide (TiO2), precipitated calcium carbonate (PCC), aluminum silicate, aluminum oxide (alumina), mica-based pigments coated with a thin layer of white pigment, or a combination of two or more thereof.

6. The recyclable shrink label according to claim 1, wherein: The recyclable shrink label includes a marking layer, and wherein the high opacity layer is disposed between the marking layer and the light blocking layer.

7. The recyclable shrink label according to claim 1, wherein: When heated to 100° C., the heat shrinkable film retracts or shrinks by about 1% to about 90%.

8. The recyclable shrink label according to claim 1, wherein: When heated to 100° C., the heat shrinkable film retracts or shrinks by about 1% to about 90% in the transverse direction.

9. The recyclable shrink label according to claim 1, wherein: When heated to 100° C., the entire recyclable shrink label retracts or shrinks by about 1% to about 90%.

10. The recyclable shrink label according to claim 1, wherein: When heated to 100° C., the entire recyclable shrink label retracts or shrinks by approximately 1% to 90% in the transverse direction.

11. The recyclable shrink label according to claim 1, wherein: The light-blocking component particles include zinc, aluminum, copper, silver, titanium dioxide, or a combination or alloy of two or more thereof.

12. The recyclable shrink label according to claim 1, wherein: The light-blocking layer contains 0.1 ppr to 10 ppr of light-blocking components.

13. A recyclable shrink label, comprising: A heat shrinkable film, comprising polyethylene terephthalate (PET) or modified polyethylene terephthalate (PETG or PET-G), wherein the heat shrinkable film has a thickness of 30 μm to 100 μm; a light-blocking layer, the light-blocking layer being arranged on the heat-shrinkable film or on an intermediate layer arranged on the heat-shrinkable film, and comprising a light-blocking component, the light-blocking layer being configured such that the recyclable shrink label blocks at least 80% of incident light having a wavelength in a range of 250 nanometers to 900 nanometers; wherein the light-blocking component comprises particles, the particles comprising at least one of the following: metals, metal oxides, reflective pigments, carbon black, mica, and combinations thereof; and wherein the dynamic coefficient of friction (COF) of the light-blocking layer is less than 0.22; The shrink label is constructed such that no ink remains on the shrink label after an alkaline wash cycle of a recycling process.

14. The recyclable shrink label of claim 13, further comprising a marking layer.

15. The recyclable shrink label according to claim 13, further comprising a high opacity layer, the high opacity layer comprising a pigment selected from the group consisting of titanium dioxide (TiO2), precipitated calcium carbonate (PCC), aluminum silicate, aluminum oxide (alumina), mica-based pigments coated with a thin layer of white pigment, or combinations thereof.

16. The recyclable shrink label according to claim 15, wherein: The recyclable shrink label includes a marking layer, wherein the high opacity layer is disposed between the marking layer and the light blocking layer.

17. The recyclable shrink label according to claim 13, wherein: When heated to 100° C., the heat shrinkable film retracts or shrinks by about 1% to about 90%.

18. The recyclable shrink label according to claim 13, wherein: When heated to 100° C., the entire heat shrinkable film retracts or shrinks by about 1% to about 90%.

19. The recyclable shrink label according to claim 13, wherein: The particles of the light-blocking component include one or more metals.

20. The recyclable shrink label according to claim 13, wherein: The light-blocking component particles include zinc, aluminum, copper, silver, titanium dioxide, or a combination or alloy of two or more thereof.

21. The recyclable shrink label according to claim 13, wherein: The light blocking layer is present in an amount of 0.5 ppr to 25 ppr.

22. The recyclable shrink label according to claim 13, wherein: The light-blocking layer contains 0.1 ppr to 10 ppr of light-blocking components.

23. A recyclable shrink label, comprising: A heat shrinkable film, comprising polyester, the polyester selected from polyethylene terephthalate (PET), modified polyethylene terephthalate (PETG or PET-G), and combinations thereof, the heat shrinkable film having a thickness of 15 to 100 microns; A light-blocking layer, the light-blocking layer comprising a light-blocking component, the light-blocking component comprising particles, the particles having a particle size of 0.1 micrometer to 100 micrometers, the particles comprising at least one of metals, metal oxides, reflective pigments, carbon black and mica, the light-blocking layer being configured so that the recyclable shrink label blocks at least 80% of incident light having a wavelength in the range of 200 nanometers to 900 nanometers.

24. The recyclable shrink label according to claim 23, wherein: The heat shrinkable film includes PETG.

25. The recyclable shrink label according to claim 23, wherein: The heat shrinkable film includes PET.

26. The recyclable shrink label of claim 23, further comprising a marking layer.

27. The recyclable shrink label of claim 23, further comprising a high opacity layer, wherein: The high opacity layer comprises a pigment selected from the group consisting of titanium dioxide (TiO2), precipitated calcium carbonate (PCC), aluminum silicate, aluminum oxide (alumina), mica-based pigments coated with a thin layer of white pigment, or a combination of two or more thereof.

28. The recyclable shrink label according to claim 27, wherein: The recyclable shrink label includes a marking layer, wherein the high opacity layer is disposed between the marking layer and the light blocking layer.

29. The recyclable shrink label of claim 23, wherein: When heated to 100° C., the heat shrinkable film retracts or shrinks by about 1% to about 90%, and optionally, wherein the heat shrinkable film retracts or shrinks by about 1% to about 90% in a transverse direction.

30. The recyclable shrink label of claim 23, wherein: When heated to 100° C., the entire heat shrinkable film shrinks or contracts by about 1% to about 90%; optionally, the entire heat shrinkable film shrinks or contracts by about 1% to about 90% in a transverse direction.

31. The recyclable shrink label of claim 23, wherein: The light-blocking component particles include zinc, aluminum, copper, silver, titanium dioxide, or a combination or alloy of two or more thereof.

32. The recyclable shrink label of claim 23, wherein: The light-blocking layer contains 0.1 ppr to 10 ppr of light-blocking components.

33. An article comprising a container and a recyclable shrink label according to any one of claims 1 to 32 applied to the container.

34. The article of claim 33, wherein the light-blocking layer is disposed between a shrink film and the container.

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