CA-3048329-C - GREASE RESISTANT PAPERBOARD AND PIZZA BOX MADE THEREWITH

Abstract

A paperboard assembly adapted for food contact comprises a contacting layer made of permeable material; an external layer; and a core layer located between the contacting layer and the external layer. The core layer is adapted to impede migration of fluid therethrough, therefore a fluid contacting the contacting layer migrates at least partially through the contacting layer and is impeded from reaching the external layer by the core layer. A describes realization is a pizza box made of the paperboard assembly and a method of manufacturing the paperboard assembly.

Inventors

• Ian MACEACHEN

Assignees

• KRUGER HOLDINGS L.P.

Dates

Publication Date

20260505

Application Date

20190627

Priority Date

20180628

Claims (8)

1. MARKED-UP COPY CLAIMS: 1. A paperboard assembly sized and shaped for use as a disposable food container, said paperboard assembly comprising at least three superimposed and bound together layers comprising: a) a food contacting layer made of material permeable to moisture and fluids that present in food being placed in said food container; b) a core layer located below the food contacting layer, the core layer having fluid-repellent characteristics impeding migration of fluids therethrough and being shaped so as to trap fluids migrating therein from said food contacting layer; c) an external layer having fluid repellency on its external outside facing side while still allowing printing thereon.
2. 2. The paperboard assembly of claim 1, wherein the core layer comprises a sprayed-on fluid-repellent compound.
3. 3. The paperboard assembly of claim 2, wherein the fluid-repellent compound comprises a grease-repellent compound.
4. 4. The paperboard assembly of claim 3, wherein the grease-repellent compound comprises Fluorinated polyether-urethane anionomer.
5. 5. The paperboard assembly of any one of claims 1 to 4, wherein the core layer comprises sub-core layers, wherein at least one of one of the sub-core layers is a repellent sub-core layer impeding migration of fluid therethrough.
6. 6. The paperboard assembly of claim 5, wherein the fluid-repellent characteristics are present throughout the repellent sub-core layer.
7. 7. The paperboard assembly of any one of claims 1 to 6, wherein the core layer is corrugated.
8. 8. A food container comprising walls made of the paperboard assembly of any one of claims 1 to 7. Date Re9ue/Date Received 2024-01-29

Description

P4572CA00 BACKGROUND (a) Field GREASE RESISTANT PAPERBOARD AND PIZZA BOX MADE THEREWITH [0001] The subject matter disclosed generally relates to paperboard material and paperboard products. More particularly, the subject matter disclosed relates to paperboard-based food containers and method of manufacturing the same. (b) Related Prior Art [0002] In the field of food containers, a particular sub-category consists of food containers designed for transportation of hot, humid, greasy and oily products, such as hot food, with an example of such containers being pizza boxes. Specific requirements are associated with this sub-category since the food, e.g., the pizza, must be kept hot in the container while maintaining its characteristics in terms of texture for instance. This type of food being somewhat greasy, the food container must be adapted to handle the grease while keeping a pleasant aspect. Up to now, no existing containers, and more particularly food container such as pizza boxes corresponds to all the requirements of such a utilization. [0003] There is therefore a need for improvement in the field of material for containers, containers, food containers, and particularly corrugated food containers for humid and/or greasy or oily content such as hot and greasy food and more specifically pizzas. SUMMARY [0004] According to an embodiment, there is provided a paperboard assembly comprising: a contacting layer made of permeable material; an external layer; and a core layer located between the contacting layer and the external layer, the core layer having fluid-repellent characteristics impeding migration of fluid therethrough; wherein a fluid contacting the contacting layer of the paperboard 1 P4572CA00 assembly migrates at least partially through the contacting layer and is impeded from reaching the external layer by the core layer. [0005] compound. [0006] According to an aspect, the core layer comprises fluid-repellent According to an aspect, the fluid-repellent compound comprises a grease-repellent compound. [0007] According to an aspect, the grease-repellent compound comprises Fluorinated polyether-urethane anionomer. [0008] According to an aspect, the core layer comprises a sub-core layers, wherein at least one of one of the sub-core layers is a repellent sub-core layer impeding migration of fluid therethrough. [0009] According to an aspect, the fluid-repellent characteristics are substantially homogeneous throughout the repellent sub-core layer. [0010] [0011] According to an aspect, the core layer is corrugated. According to an embodiment, there is provided a method of manufacturing grease-repellent paperboard on a paperboard machine comprising a press section, the method comprising: forming a first external layer on the paperboard machine; spraying a fluid-repellent compound on pulp used for forming a core layer after dewatering of the pulp thereof; forming the core layer from the sprayed pulp on the paperboard machine; forming a second external layer on the paperboard machine; and assembling the first external layer, the second external layer and the core layer in-between in the paperboard machine prior to assembling the first external layer, the core layer and the second external layer into the paperboard on the press section; whereby the paperboard thereby comprises a fluid-repellent core layer between two external layers, and wherein the core layer is adapted to impede migration of fluid therethrough. 2 P4572CA00 [0012] According to an aspect, spraying a fluid-repellent compound on pulp comprises spraying a grease-repellent compound. [0013] According to an aspect, the method further comprises processing the pulp with a couch roller, wherein the step of spraying the grease-repellent compound is performed before processing the pulp with the couch roller. [0014] According to an aspect, the method further comprises generating a plurality of sub-layers from the pulp; and assembling the plurality of sub-layers into the core layer, wherein at least one of the sub-layers is sprayed with a greaserepellent compound. [0015] According to an aspect, the method further comprises mechanically deforming or shaping the core layer. [0016] According to an aspect, the method further comprises gluing the core layer to at least one of the first external layer and the second external layer. [0017] According to an aspect, the method further comprises generating a grease-repellent compound comprising Fluorinated polyether-urethane anionomer. [0018] According to an aspect, the step of generating the grease-repellent compound further comprises adding Ethylenediaminetetraacetic acid (EDTA). [0019] According to an aspect, the step of generating the grease-repellent compound further comprises adding a biocide. [0020] According to an aspect, the step of spraying the fluid-repellent compound comprises dosing an amount of between about 5 and 15 kg of greaserepellent compound per metric ton of produced paperboard. [0021] According