US-12617187-B2 - Multilayer film for packaging and method of manufacture thereof

US12617187B2US 12617187 B2US12617187 B2US 12617187B2US-12617187-B2

Abstract

Disclosed is a multilayer film for packaging. The multilayer film has a layer of ink and an adjacent layer of substrate. The layer of ink includes functionalised graphene and a material selected from cellulose, polylactic acid and a polyhydroxyalkanoate.

Inventors

Stefano BORINI
Malik QASIM
Simon Broughton

Assignees

Toraphene Limited

Dates

Publication Date: 20260505
Application Date: 20240506
Priority Date: 20170526

Claims (8)

1 . A multilayer film for packaging comprising: a first layer of substrate comprising a first layer of ink deposited on a surface of the first layer of substrate, a second layer of substrate comprising a second layer of ink deposited on a surface of the second layer of substrate, wherein the first layer of ink and the second layer of ink comprise functionalized graphene and cellulose interspersed, wherein the first layer of substrate and the second layer of substrate have functional groups that interact with a functional group of the functionalized graphene; wherein the first layer of ink and the second layer of ink are nano-fibrous structures formed by the functionalized graphene interspersed with the cellulose; and wherein the first layer of ink and the second layer of ink are sandwiched between the first layer of substrate and the second layer of substrate, wherein the first layer of ink is arranged between the first layer of substrate and the second layer of ink and wherein the second layer of ink is arranged between the second layer of substrate and the first layer of ink.
2 . The multilayer film of claim 1 , wherein a thickness of the first layer of ink and a thickness of the second layer of ink is in a range of 1 nanometer to 10 micrometers, and a thickness of the first layer of substrate and a thickness of the second layer of substrate is in a range of 10 micrometers to 500 micrometers.
3 . The multilayer film of claim 1 , wherein the functional group of the functionalized graphene is at least one of: aliphatic ester, aromatic ester, amine, epoxide, carboxyl, hydroxyl, siloxanes, silanes.
4 . The multilayer film of claim 1 , wherein a concentration of cellulose is in a range of 0.5 to 20% by weight.
5 . The multilayer film of claim 1 , wherein the first layer of substrate or the second layer of substrate is polyethylene terephthalate.
6 . The multilayer film of claim 1 , wherein the first layer of substrate and the second layer of substrate are pre-treated substrates, and the pre-treated substrates and the functionalized graphene comprise a dodecyl-amine functional group.
7 . The multilayer film of claim 1 , wherein the functionalized graphene and cellulose interspersed was formed by solvent dispersion, wherein the solvent dispersion comprises a binder with a functional group compatible with the functional group of the functionalized graphene.
8 . The multilayer film of claim 7 , wherein the binder is one of: natural rubber, synthetic rubber, alkane polymer, alkene polymer, polyamide, polyurethane.

Description

TECHNICAL FIELD The present disclosure relates generally to packaging material; and more specifically, to multilayer film for packaging. Moreover, the present disclosure is concerned with methods of manufacturing aforesaid multilayer film for packaging. BACKGROUND Typically, packaging plays an indispensable part in storage and transportation of goods. Consequently, the role of packaging films is significant. Generally, packaging films protect the goods from damages from environmental factors such as pollution, rain and moisture, and from damages during transportation such as wear and tear, breakage and so forth. Furthermore, packaging films may assist in identification of the goods. Additionally, when used for food packaging, packaging films may isolate the food from external environment and prevent oxidation thereof. Conventionally, packaging films employ metals and polymers for protection of goods. Generally, metals are employed to provide mechanical robustness to the packaging films. Additionally, polymers, specifically, thermoplastics such as polypropylene or polyethylene terephthalate are employed to provide a barrier layer between the goods and external environment. Furthermore, a combination of metals, such as aluminium, and polymers may be employed in packaging films. Such combination packaging films provide superior mechanical robustness and isolation of goods. However, recycling of such combination films may be difficult. Generally, use of metals or polymers in packaging films does not provide desirable protection of the goods from external damage. With increase in environmental awareness, use of non-recyclable packaging films has been a growing concern. Additionally, use of metals may significantly increase weight of the packaging film. Consequently, increased weight of the packaging film may lead to difficulty in handling and higher transportation costs. Furthermore, conventional packaging films are mechanically weak and may be subject to wear and tear. Therefore, in light of the foregoing discussion, there exist problems associated with conventional packaging films. SUMMARY The present disclosure seeks to provide an improved multilayer film for packaging. The present disclosure also seeks to provide an improved method of manufacturing a multilayer film for packaging. According to a first aspect there is provided a multilayer film for packaging comprising: a layer of ink comprising functionalised graphene and a material selected from cellulose, polylactic acid and a polyhydroxyalkanoate; andan adjacent layer of substrate deposited with the layer of ink. The present disclosure seeks to provide an improved, recyclable, light-weight multilayer film for packaging; moreover, employs functionalised graphene to provide higher mechanical robustness to the multilayer film. Optionally, the multilayer film further including a second layer of substrate such that the layer of ink is sandwiched between the layers of substrate. Optionally, the multilayer film further including a second layer of ink between the second layer of substrate and the layer of ink. Optionally, the functionalised graphene includes at least one of a functional group: aliphatic ester, aromatic ester, amine, epoxide, carboxyl, hydroxyl, siloxanes, silanes. Optionally, concentration of the material selected from cellulose, polylactic acid and a polyhydroxyalkanoate mixed with the functionalised graphene may be in a range of 0.5 to 20 weight %. Optionally, the substrate is polyethylene terephthalate. According to a second aspect, there is provided a method for manufacturing a multilayer film for packaging, the method comprising: providing functionalised graphene;mixing the functionalised graphene with a material selected from cellulose, polylactic acid and a polyhydroxyalkanoate;dispersing the mixture of the functionalised graphene and the material in a solvent to form an ink; anddepositing a layer of ink on a layer of substrate to form the multilayer film. Optionally, the method further includes applying a second layer of substrate on the deposited layer of ink to sandwich the deposited layer of ink between the layers of substrate. Optionally, the method includes depositing a second layer of ink between the second layer of substrate and the deposited layer of ink. More optionally, the method includes arranging for each of the layers of ink and each of the layers of substrate to include a thickness in a range of 1 nanometres to 10 micrometres and a thickness in a range of 10 micrometres to 500 micrometres, respectively Optionally, the method includes arranging for the functionalised graphene to include at least one of a functional group: aliphatic ester, aromatic ester, amine, epoxide, carboxyl, hydroxyl, siloxanes, silanes. Optionally, the method includes treating the substrate prior to deposition of the layer of ink thereon. Optionally, the method includes treating the substrate includes at least one of: functionalizing, washing, coating.