Post-consumer resin packaging

Abstract

The present invention relates to sustainable articles for packaging that can be made substantially free of virgin petroleum-based compounds; in particular, the present invention relates to new packaging made from colored post-consumer resins (PCR) with high NIR absorption. There remains a need to establish a circular economy for colored and / or black plastics by bringing waste colored and black plastics into new packaging while using near infrared (NIR) detectable pigments in colorant masterbatches. Therefore, an object of the present invention is to bring colored or black plastic waste into new packaging. It has been found that consumer-acceptable black sustainable packaging using NIR detectable pigments can be obtained by using a multi-layer post-consumer resin, comprising a thinner outer layer of natural plastic waste post-consumer resin (N‑PCR); and a thicker inner layer comprising at least 50% colored plastic waste (J‑PCR).

Description

Technical Field

[0001] The present invention relates to a sustainable article for packaging that can be made substantially free of virgin petroleum-based compounds; in particular, the present invention relates to new packaging made from colored post-consumer resin (PCR) with high NIR absorption. Background Art

[0002] Plastics have become an integral part of people's lives around the world, but with them comes the growing problem of plastic waste. Plastics are useful and versatile materials that are low-cost and easy to use. The problem is not the use of plastics, but the single use of plastics. Through a single use of plastics, 95% of their value is lost.

[0003] However, recent years have witnessed a significant effort to recycle plastics. Plastics that have been collected, sorted, washed and reprocessed into pellets through established consumer recycling streams are defined as post-consumer resin (PCR). This can be used in place of virgin resin to create new plastic packaging for consumer products.

[0004] Plastic recycling efforts are becoming larger in scale, enabling grade sorting. Broadly defined, there are food grade and non-food grade PCR materials.

[0005] Non-food grade PCR is generally divided into 4 types: recycled high-density polyethylene (HDPE), recycled polypropylene (PP), recycled low-density polyethylene (LDPE) and recycled polyethylene terephthalate (PET).

[0006] Recycled HDPE comes in three grades: natural PCR (transparent) obtained from milk or dairy waste bottles, off-white PCR (opaque) obtained from white and / or light-colored bottles, and grey PCR (light or dark) obtained from mixed-color bottles.

[0007] While natural and off-white grades can be easily used to make new packaging as white or colored bottles or containers, this is not the case with the use of gray PCR due to its gray color. It is believed that gray pellets can be used to prepare darker packaging materials, such as black or black shades. However, when attempts were made to color gray PCR with a black pigment detectable by near infrared (NIR) spectroscopy, it was observed that the color obtained was not a true black and there was a significant difference in color when compared to the black color of virgin plastic colored with the same detectable black pigment, thus making the recycled bottles unsuitable for sale; at least for the sale of premium products.

[0008] A possible alternative could be to use carbon black as a pigment. However, plastics or PCRs colored with carbon black cannot be detected by automated near infrared (NIR) sorting systems, which are primarily used in material recovery facilities (MRFs), plastic recovery facilities (PRFs) and reprocessors to separate plastics into different polymer streams for reprocessing into PCRs. Therefore, carbon black colored plastics usually end up as unsorted residues, which are less suitable for reprocessing and are usually disposed of as waste.

[0009] EP 0 654 496 A2 discloses a plastic container made from a post-consumer resin, in particular a lightweight plastic container, which is resistant to stress cracking and includes at least one layer comprising a post-consumer plastic film resin; a fusion blend of a post-consumer plastic film resin and a post-consumer plastic milk resin; or a fusion blend of a post-consumer plastic film resin, a post-consumer plastic latex resin and a virgin high-density ethylene copolymer plastic material.

[0010] Therefore, there remains a need to create a circular economy for colored and / or black plastics by bringing discarded colored and black plastics into new packaging while using near infrared (NIR) detectable pigments in colorant masterbatches.

[0011] Therefore, the object of the present invention is to bring colored or black plastic waste into new packaging.

[0012] Another object of the present invention is to provide a sustainable article for packaging that may be substantially free of virgin petroleum-based compounds.

[0013] Yet another object of the present invention is to provide a sustainable product made from colored or black plastic waste while using near infrared (NIR) detectable pigments as colorant masterbatch.

[0014] Another object of the present invention is to provide a black article having a PCR exceeding 95%.

[0015] Yet another object of the present invention is to provide a black colored article having a PCR exceeding 95% and reduced odor.

[0016] It is yet another object of the present invention to provide such sustainable packaging in a black color that is acceptable to consumers.

[0017] Surprisingly it has been discovered that sustainable packaging in a consumer acceptable black color using NIR detectable pigments can be obtained by using multiple layers of post-consumer resin, comprising a thinner outer layer of natural plastic waste post-consumer resin (N-PCR); and a thicker inner layer comprising at least 50% colored plastic waste (J-PCR). Summary of the invention

[0018] Therefore, in a first aspect, the present invention provides a sustainable article for packaging, comprising multiple layers of post-consumer resin (PCR), wherein the multiple layers include: an outer layer comprising post-consumer resin from natural plastic waste (N-PCR); and an inner layer comprising post-consumer resin from natural plastic waste (N-PCR) or colored plastic waste (J-PCR), wherein at least 50% of the inner layer comprises post-consumer resin from colored plastic waste (J-PCR), wherein the outer layer and / or the inner layer comprises a NIR detectable colorant masterbatch.

[0019] In a second aspect, the present invention provides the use of an article according to any invention for packaging fast moving consumer goods (FMCG).

[0020] In the context of the present invention, reference to "post-consumer resin (PCR)" generally refers to plastics that have been collected, sorted, washed, and reprocessed into pellets through established consumer recycling streams.

[0021] In the context of the present invention, reference to "sustainable" generally refers to a material that has an improvement of more than 10% in some aspects of its Life Cycle Assessment or Life Cycle Inventory when compared to the relevant virgin petroleum-based plastic materials originally used to manufacture the article. As used herein, "Life Cycle Assessment" (LCA) or "Life Cycle Inventory" (LCI) refers to the investigation and evaluation of the environmental impact caused or required by a given product or service due to its existence. LCA or LCI may involve a "cradle-to-grave" analysis, which refers to a full life cycle assessment or life cycle inventory from manufacturing ("cradle") to the use phase and disposal phase ("grave"). For example, a high-density polyethylene (HDPE) container can be recycled into HDPE resin pellets, which are then used to form containers, films or injection molded products, for example, saving a large amount of fossil fuel energy. At the end of its life, polyethylene can be disposed of, for example, by incineration. All inputs and outputs of all stages of the life cycle are considered.

[0022] By reading the following detailed description and the appended claims, these and other aspects, features and advantages will become apparent to those of ordinary skill in the art. For the avoidance of doubt, any feature of one aspect of the present invention may be used in any other aspect of the present invention. The word "comprising" is intended to mean "including", but not necessarily "consisting of" or "composed of". In other words, the steps or options listed do not need to be exhaustive. It should be noted that the examples given in the following description are intended to illustrate the present invention and are not intended to limit the present invention to those examples themselves. Similarly, unless otherwise indicated, all percentages are weight / weight percentages. Except in the operating examples and comparative examples, or in the case of otherwise clearly indicated, all numbers representing the amount of material or reaction conditions, the physical properties of the material and / or the use in this specification should be understood to be modified by the word "about". Numerical ranges expressed in the format of "x to y" should be understood to include x and y. When multiple preferred ranges are described in the form of "x to y" for a particular feature, it should be understood that all ranges combining different endpoints are also considered. DETAILED DESCRIPTION

[0023] In a first aspect, the present invention relates to a sustainable article for packaging. The sustainable article of the present invention is made from post-consumer resin (PCR) and is preferably substantially free of virgin plastic.

[0024] By "substantially free" it is meant that the article comprises less than 5 wt%, preferably less than 3 wt%, more preferably less than 2 wt%, even more preferably less than 1 wt% or even 0 wt% of virgin plastic.

[0025] The PCR used in the present invention is recycled polyethylene, preferably recycled high density polyethylene (HDPE).

[0026] Preferably, the articles of the present invention comprise multiple layers of post-consumer resin (PCR).

[0027] The multilayer comprises at least two layers: an outer layer and an inner layer.

[0028] The outer layer is generally the layer located on the outside of the article and is generally directly visible to the consumer.

[0029] The outer layer of the multi-layer comprises post-consumer resin (N-PCR) of natural plastic waste. Natural plastic waste typically comes from discarded milk bottles or dairy bottles or the like.

[0030] The inner layer of the multilayer comprises post-consumer resin of natural plastic waste (N-PCR) or post-consumer resin of colored plastic waste (J-PCR). Preferably, at least 50% of the inner layer comprises post-consumer resin of colored plastic waste (J-PCR). Preferably, the inner layer comprises at least 60%, more preferably at least 70%, even more preferably at least 80%, still more preferably at least 90% or even 100% of colored plastic waste (J-PCR).

[0031] Colored plastic waste typically comes from discarded colored and / or mixed consumer product bottles. Post-consumer resin from colored plastic waste is often referred to as Jazz PCR (J-PCR).

[0032] Both N-PCR and J-PCR are commercially available from various suppliers such as Viridor, QCP and BIFFA in Europe and KW plastics in North America.

[0033] When present as a bilayer, the weight ratio of outer layer to inner layer is generally from 99:1 to 1:99, but preferably from 1:1, more preferably 3:7 or even 1:3, and preferably to 1:20, more preferably to 1:10 or even to 1:5.

[0034] The multilayers of the present invention may also include a second inner layer which, when present, will be the innermost layer, which is typically the layer in contact with the product.

[0035] When present, the second inner layer comprises natural plastic waste post-consumer resin (N-PCR).

[0036] While the use of an outer layer of N-PCR is primarily intended to provide a more intense color on the outside of the article, providing a second inner (or innermost) layer of N-PCR in a multi-layer article reduces odors that typically come from J-PCR.

[0037] When present as three layers, the weight ratio of outer layer to inner layer to second inner layer is from 1:1.5:1 to 1:98:1, but preferably from 1:2:1, more preferably 1:3:1, while preferably to 1:18:1, more preferably to 1:10:1 or even to 1:8:1 or even to 1:5:1.

[0038] Preferably, the outer layer and / or the inner layer comprises a colorant masterbatch. More preferably, the outer layer comprises a colorant masterbatch. "Colorant masterbatch" refers to a mixture in which a pigment is dispersed in a carrier material at a high concentration. A colorant masterbatch is used to impart color to an article.

[0039] The carrier may be a bio-based or petroleum-based plastic, or a bio-based or petroleum-based oil or made from post-consumer resin (PCR).

[0040] Non-limiting examples of carriers include bio-derived or oil-derived polyethylene (e.g., LLDPE, LDPE, HDPE), bio-derived oils (e.g., olive oil, rapeseed oil, peanut oil), petroleum-derived oils, recycled oils, bio-derived or petroleum-derived polyethylene terephthalate, polypropylene, recycled high-density polyethylene (rHDPE), recycled low-density polyethylene (rLDPE). Preferably, the carrier is recycled high-density polyethylene (rHDPE) or recycled low-density polyethylene (rLDPE).

[0041] When it is desired that all layers be made of 100% PCR, the vector is also preferably selected from PCR. Similarly, when it is desired that a layer have 100% of a particular PCR, the vector is preferably selected from the same PCR.

[0042] The pigment of the masterbatch (when present) is a NIR detectable pigment. Carbon black is not preferred within the scope of the present invention. The NIR detectable pigment is preferably black. The pigment is usually made from a combination of known colors.

[0043] Consumer acceptable black can be defined as a color measured using a reflectometer and expressed as a CIE L*a*b* value, with a value of L less than 25, preferably less than 23, more preferably less than 20, even more preferably less than 15, still more preferably less than 12 or even less than 10, a value in the range of -5 to 5, preferably -2 to 3, more preferably 0 to 2, and b value in the range of -10 to 10, preferably -8 to 5.

[0044] NIR detectable pigments are those detectable by near infrared (NIR) spectroscopy.

[0045] The pigment of the carrier may include, for example, an inorganic pigment, an organic pigment, a polymer resin, or a mixture thereof.

[0046] Optionally, the colorant masterbatch may further include one or more additives. Non-limiting examples of additives include slip agents, UV absorbers, nucleating agents, UV stabilizers, heat stabilizers, clarifying agents, fillers, brighteners, processing aids, fragrances, flavoring agents, and mixtures thereof.

[0047] Such NIR detectable pigments are known in the art and are supplied by various suppliers, such as Clariant globally and Colourtone Masterbatch Ltd in Europe.

[0048] The article according to the present invention is preferably a container; in particular, the article according to the present invention is a non-food grade container.

[0049] method

[0050] The articles of the present invention can be produced using blow molding. Blow molding is a manufacturing process that forms hollow plastic parts from thermoplastic materials. The blow molding process begins by melting the thermoplastic and forming it into a parison or preform. The parison is a tubular plastic part that has a hole at one end through which compressed air can pass. Pressurized gas (usually air) is used to expand the parison or hot preform and press it against the mold cavity. The pressure is maintained until the plastic cools. After the plastic has cooled and hardened, the mold is opened and the part is ejected.

[0051] There are three main types of blow molding: extrusion blow molding, injection blow molding, and injection stretch blow molding. In extrusion blow molding, a molten plastic tube is extruded into a mold cavity and inflated with compressed air. One end of the cylinder is clamped closed. After the plastic part cools, it is removed from the mold. Extrusion blow molding can be used to produce the multilayer article of the present invention.

[0052] use

[0053] In another aspect, the present invention provides the use of an article according to the invention for packaging fast moving consumer goods (FMCG), such as personal care products, beauty products, cosmetics, home care products and / or food products.

[0054] Example

[0055] Example 1

[0056] In this example, a bottle having an inner layer and an outer layer made of J-PCR and 80% of the layers, 1% of which were coloured with Colourtone F95884 and 4% of which were coloured with Colourtone F95884 (Comparative Example A) was compared with a bottle having a layer according to the invention and 80% of the layers, 1% of which were coloured with Colourtone F95884 and 4% of which were coloured with Colourtone F95884 (Example 1).

[0057]

[0058] Pantone Color Coding L value a value b-value Comparative Example A Pantone 432c 25.68 -2.8 -7.33 Example 1 Pantone 532c 11.95 1.26 -7.71 Comparison Pantone 2c 19.37 0.31 9.78

[0059] Even when colored with a black color masterbatch (Colourtone F95884), the resulting color of the bottle of Comparative Example A is greyer. The desired consumer-acceptable black color is achieved in the control bottle using virgin HDPE for both layers. This color matches the color of the bottle having a layer according to the invention (Example 1) but not the bottle of Comparative Example A.

[0060] Example 2

[0061] In this example, a three-layer bottle having all layers made of J-PCR and 3% of the 60% middle layer (inner layer) being colored with Clariant PE94000797 and 3% of the 20% outer layer being colored with Clariant PE94000804 (Comparative Example B) was compared with bottles having layers according to the invention and 3% of the 60% middle layer (inner layer) being colored with Clariant PE94000797 and 3% of the 20% outer layer being colored with Clariant PE94000804 (Examples 2 and 3).

[0062]

[0063] Even with black color masterbatch (intermediate (inner) layer Clariant PE94000797 and outer layer Clariant PE94000804), the resulting color of the bottle of Comparative Example B was gray. The desired consumer-acceptable black color was obtained in bottles of Examples 2 and 3 with layers according to the invention, but not Comparative Example B.

Claims

1. A sustainable article for packaging comprising multiple layers of post-consumer resin (PCR), wherein the multiple layers comprise: a outer layer comprising post-consumer resin (N-PCR) from natural plastic waste; and b an inner layer comprising post-consumer resin of natural plastic waste (N-PCR) or post-consumer resin of colored plastic waste (J-PCR), wherein at least 50% of said inner layer comprises post-consumer resin of colored plastic waste (J-PCR), wherein the outer layer and / or the inner layer comprises a NIR detectable colorant masterbatch, and wherein the article is substantially free of virgin plastic, by “substantially free” it is meant that the article comprises less than 5 wt% of virgin plastic; and The weight ratio of the outer layer to the inner layer is 1:3 to 1:

5.

2. The article according to claim 1, wherein the inner layer comprises 100% colored plastic waste (J-PCR).

3. The article according to claim 1 or 2, wherein the weight ratio of the outer layer to the inner layer is 1:

4.

4. The article of claim 1 or 2, wherein the multiple layers include a second inner layer.

5. The article of claim 1 or 2, wherein the NIR detectable colorant masterbatch is black.

6. The article according to claim 1 or 2, wherein the plastic waste is waste high-density polyethylene (HDPE).

7. The article of claim 1 or 2, wherein the article comprises less than 3% virgin plastic.

8. The article of claim 1 or 2, wherein the article comprises 0% virgin plastic.

9. The article of claim 1 or 2, wherein the article is a container.

10. The article of claim 1 or 2, wherein the article is a non-food grade article.

11. Use of the preparation according to any one of claims 1 to 10 for packaging fast moving consumer goods (FMCG).

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