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EP-4737641-A1 - COATED PAPER LINER

EP4737641A1EP 4737641 A1EP4737641 A1EP 4737641A1EP-4737641-A1

Abstract

A coated paper liner serves as both exterior packaging and an interior release liner for consumer products. The liner comprises a paper sheet layer with a first polymeric composition, such as a thermoplastic elastomer or polymer, forming a film on at least a portion of a surface of the paper sheet. The liner may also comprise a flexibility agent that enhances pliability and noise reduction during handling. The liner may include a release agent, like silicone, to prevent adhesion of consumer products to the liner. The method of manufacturing involves coating the paper sheet with the polymeric composition and flexibility agent, followed by drying. This solution offers a sustainable alternative to plastic films, providing to the liner heat-sealability, barrier properties, and recyclability.

Inventors

  • VALERA, NATACHA
  • Rodiño Lopez, José Antonio
  • Urquiola Zaballa, Francisco Borja
  • Canales Perez, Jorge

Assignees

  • Industrias de Transformacion de Andoain, S.A.U

Dates

Publication Date
20260506
Application Date
20250716

Claims (15)

  1. A coated paper liner comprising: a first layer comprising a paper sheet layer; a first coating comprising a first polymeric composition selected from the group consisting of a thermoplastic elastomer, a thermoplastic polymer, or combinations thereof that forms a film on at least a portion of a surface of the paper sheet layer; and wherein the paper liner further comprises one or more additional component, being said one or more additional component selected from the group consisting of a flexibility agent and a release agent.
  2. The coated paper liner of claim 1, wherein the first polymeric composition is a thermoplastic elastomer dispersion, preferably the thermoplastic elastomer dispersion comprises a polymer selected from the group consisting of ethylene C 1-6 alkyl acrylate copolymer, ethylene C 1-6 alkyl acrylic acid copolymer, vinyl acetate-ethylene copolymer, ethylene vinyl acetate, polyvinyl acetate copolymer, polyethylene, and combination thereof; more preferably the thermoplastic elastomer dispersion comprises a blend of ethylene ethyl acrylate and ethylene vinyl acetate.
  3. The coated paper liner of any of claims 1 or 2, wherein the flexibility agent is selected from the group consisting of a polymeric gelling agent, an oily component, a surfactant, a polyol, and combinations thereof; preferably the flexibility agent is a polyol selected from a group consisting of glycerin, sorbitol, C 1-6 alkylene glycol, xylitol, and combination thereof, more preferably the polyol is glycerin.
  4. The coated paper liner of any of claims 1 to 3, wherein the release agent comprises a silicone selected from the group consisting of addition-curing solventless silicone, addition-curing silicone emulsion, UV-cured silicone, and solvent-based silicone.
  5. The coated paper liner of any of claims 1 to 4, wherein the paper sheet layer comprises the flexibility agent.
  6. The coated paper liner of any of claims 1 to 5, wherein the first coating comprises a first mixed coating of the first polymeric composition and the flexibility agent, wherein an amount of the first mixed coating is from 0.1 to 10 g per m 2 of the paper sheet, preferably from 2 to 7 g per m 2 of the paper sheet, more preferably from 3 to 5 g per m 2 of the paper sheet.
  7. The coated paper liner of any of claims 1 to 6, wherein the first polymeric composition and flexibility agent are in a weight ratio of from 50:50 to 95:5, preferably from 60:40 to 90:10, more preferably approximately 85:15.
  8. The coated paper liner of claims 1 to 7, further comprising a second coating comprising a release agent that forms a film on at least a portion of a surface of the paper sheet.
  9. The coated paper liner of any of claims 1 to 5, wherein the first coating comprises a second mixed coating of the first polymeric composition and the release agent, wherein an amount of the second mixed coating is from 0.1 to 10 g/m 2 , preferably from 0,6 to 7 g/m 2 , more preferably from 3 to 5 g/m 2 of the paper sheet.
  10. The coated paper liner of claim 9, wherein the first polymeric composition and release agent are in a weight ratio of from 30:70 and 95:5, preferably between 70:30 and 85:15.
  11. The coated paper liner of any of claims 1 to 4, wherein the first coating comprises a third mixed coating of the first polymeric composition, the flexibility agent and the release agent, wherein an amount of the third mixed coating is from 0.1 to 10 g/ m 2 of the paper sheet, preferably from 0,6 to 7 g/m 2 , more preferably from 3 to 5 g/m 2 .
  12. The coated paper liner of claim 11, wherein wherein the release agent is in a weight% from 5 to 70wt%, preferably from 15 to 30wt%, the first polymeric composition is in a weight% from 30 to 95 wt%, preferably from 40 to 60 wt% and the flexibility agent is in a weight% from 5 to 50 wt%, preferably from 20 to 30 wt%, based on 100 weight parts of the third mixed coating.
  13. The coated paper liner of any of claims 1 to 12, wherein the paper sheet has a grammage of from 10 to 120 g/m 2 , preferably from 15 to 100 g/m 2 , more preferably from 20 to 90 g/m 2 .
  14. The coated paper liner of any of claims 1 to 13, wherein a heat-sealing force of the paper liner is equal to or greater than 0.01N.
  15. Packaging comprising the coated paper liner of any of claims 1 to 14.

Description

Technical Field This disclosure pertains to the field of flexible packaging for consumer products. Background Art Individually packaged consumer products are generally wrapped in a protective pouch, bag, envelopes, or the like which may be heat-sealed to enclose and protect the product from external elements such as dirt, moisture, oil, oxygen, or other airborne contaminants. Plastic films have been previously used for such packaging, however, reliance on plastic materials poses environmental concerns, as they generate waste that is difficult to manage and recycle. Additionally, packaging of certain consumer products poses the additional challenge of preventing unintended adhesion or material transfer between the consumer product and the interior of the packaging. In addition, some products are sensitive to humidity, oxygen grease that may penetrate the package and deteriorate the packaged product. Previous attempts to prevent these issues included the use of an intermediate release liner to act as a barrier between the packaging and the product. The addition of a release liner complicates the manufacturing process, increases costs, and increases the amount of waste produced. For cost reduction, packaging simplification, and environmental sustainability, packaging and release liners may be formed as a single packaging solution, eliminating the need for separate release liners and packaging. Previous attempts to produce packaging-release liner combinations have been formed of silicone-coated plastic films. Such films provide sufficient heat-sealability and flexibility, however, they produce solid waste which may not be recyclable. The production and disposal of plastic films have a significant carbon footprint, which further exacerbates environmental issues. There exists a need for a more environmentally sustainable packaging which eliminates the need for plastic film while maintaining proper heat-sealability, barrier properties, and flexibility, and in some instances, product releasability. Summary Accordingly, this invention presents a coated paper liner and manufacturing method thereof that addresses the aforementioned challenges. The coated paper liner can be formed into a container, such as a pouch, bag, or envelope, and may serve as both exterior packaging and an interior release liner for consumer products. By coating at least a portion of the paper with a first polymeric composition, a flexibility agent, and optionally, a release agent, or with a first polymeric composition, and one or more of a release agent and a flexibility agent, the solution provides a sustainable alternative to traditional plastic films. This approach not only reduces solid waste but also enhances recyclability, offering a more environmentally friendly packaging solution. In general, the invention is carried out by coating at least a portion of a paper sheet with one or more coatings comprising independently a first polymeric composition, and one or more of a release agent and a flexibility agent, or with a first polymeric composition, and optionally, a release agent and a flexibility agent. Brief Description of Drawings Fig. 1 is a schematic of an example coated paper liner according to the present invention.Fig. 2 is a schematic of an example coated paper liner according to the present invention.Fig. 3 is a schematic of an example coated paper pouch according to the present invention.Fig. 4 is a schematic of an example coated paper bag according to the present invention.Fig. 5A-D are schematics of example methods of manufacturing a coated paper liner according to the present invention. Description of Embodiments This description and the accompanying drawings describe different embodiments encompassed by the claims for illustration purposes and should not be taken as limiting, with the claims defining the scope of the present invention. Various mechanical, compositional, structural, and operational changes may be made without departing from the scope of this description and the claims. In some instances, structures and techniques well-known in the field of the invention have not been shown or described in detail so as not to obscure the description. Like numbers in two or more figures represent the same or similar elements. Furthermore, elements and their associated aspects that are described in detail with reference to one embodiment may, whenever practical, be included in other embodiments in which they are not specifically shown or described. For example, if an element is described in detail with reference to one embodiment and is not described with reference to a second embodiment, the element may nevertheless be claimed as included in the second embodiment. Moreover, the depictions herein are for illustrative purposes only and do not necessarily reflect the actual shape, size, or dimensions of the system or illustrated components. It is noted that, as used in this specification and the appended claims, the singular forms