Prior art

To identify the most relevant prior art for US Patent 11072148, I would typically access the USPTO Patent Public Search database (https://ppubs.uspto.gov/pubwebapp/) and retrieve the full patent document. From this document, I would then review the "References Cited" section, which lists the prior art considered by the patent examiner during prosecution.

Since I cannot directly interact with the USPTO database in real-time, I will rely on the implicit and explicit descriptions of prior art contained within the provided patent text of US11072148 itself, particularly in the "BACKGROUND" and "DETAILED DESCRIPTION" sections. The patent thoroughly discusses several categories of existing technologies that it seeks to improve upon, which serve as foundational prior art for a § 102 analysis. While these are presented as types of prior art rather than specific patent numbers in the provided text, they represent the key challenges and existing solutions that the claimed invention aims to overcome.

For a strict 35 U.S.C. § 102 anticipation analysis, specific patent or publication references are required. The patent text does, however, cite specific industry standards and general approaches that constitute the state of the art. The IPR challenge previously mentioned also explicitly cited US patent publications. Therefore, I will include those specifically mentioned in the IPR and also infer from the patent's own background description what general types of prior art are most relevant for a § 102 analysis, even if not given a specific patent number in the provided document.

Based on the provided patent text, the most relevant types of prior art, which would be represented by specific patent citations in a complete analysis, are:

Most Relevant Prior Art Categories (as described in US11072148)

1. Aluminum Foil Laminated to Paper:

   • Description from Patent: This refers to packaging materials where aluminum foil (typically 6-18 microns thick) is laminated to paper. It offers low emissivity (0.03-0.05, rising to 0.08-0.12 after initial oxidation).
   • Issue Addressed by US11072148: A recognized disadvantage is that aluminum foil is difficult to remove from paper during repulping and recycling. It breaks apart, and its crumbs contaminate the paper pulp, making the final paper product unusable or causing defects. [cite: "A recognized disadvantage to using an aluminum foil in an insulating packaging container is that the aluminum foil is very difficult to remove from the paper if such a container is to be repulped or recycled. In particular, the aluminum foil is so soft that it can and often does break apart or crumble, and its crumbs or particles make their way into the paper pulp."]
   • Potential Anticipation (35 U.S.C. § 102): While providing low emissivity, this prior art generally does not anticipate the key recyclability feature of US11072148, which requires the aluminum layer to become "fully oxidized with no visible aluminum present" after a specific recycling treatment. The patent explicitly distinguishes itself by solving the problem of aluminum foil contamination.

2. Aluminized Paper (Vacuum-Deposited Aluminum on Paper):

   • Description from Patent: Here, a thin aluminum layer (200 nanometers or less) is applied directly to paper using vacuum deposition. The weight of this aluminum is considered "insignificant" for meeting the 85% repulpability requirement.
   • Issue Addressed by US11072148: Due to the paper's rough surface, the emissivity of aluminized paper is higher (0.10-0.50), often failing to meet the radiant barrier standard of 0.10 or less. It is also susceptible to corrosion without protection. [cite: "Since the paper generally does not have a smooth, planar surface, the emissivity of the paper surface does not reach as low a value as that of aluminum foil. Depending on the type of paper, the amount of moisture in the paper, roughness of the paper surface and some other factors, we measured the emissivity of aluminized paper samples to be between 0.50 and 0.10."]
   • Potential Anticipation (35 U.S.C. § 102): This prior art may anticipate the concept of a thin aluminum layer (200nm or less) on a paper-containing substrate and its minimal weight impact on repulpability. However, it does not anticipate the claimed low emissivity (≤0.10) combined with the specific layered structure (polymer layer between paper and aluminum) that allows for a smoother surface, nor the specific functional characteristic of full oxidation with no visible aluminum after the defined recycling treatment to the extent that it passes spot/stickies tests for paper quality.

3. Metalized Polymeric Film (Vacuum-Deposited Aluminum on Polymer Film):

   • Description from Patent: This involves vacuum-depositing a thin aluminum layer (200 nanometers or less) onto a polymer film (e.g., PET, LDPE). This approach can achieve very low emissivity values (0.03 for aluminized PET, 0.05 for aluminized LDPE) due to the film's smooth surface. These films can also be coated for surface smoothing or corrosion protection.
   • Issue Addressed by US11072148: The primary problem is that metalized polymeric film itself is not paper and cannot be directly repulped for paper recycling. It traditionally requires separation from paper components. [cite: "Notably, because such film is not paper itself, it simply cannot be repulped for paper recycling, and instead must be separated from the paper to which it is affixed, beforehand, to allow the remaining paper portion to be recycled."]
   • Potential Anticipation (35 U.S.C. § 102): This prior art anticipates the low emissivity achievable with a thin aluminum layer on a polymer film (as required by Claims 1, 13, 17, 21, 25). However, it does not anticipate the combination with a paper layer in a recyclable as paper packaging where the aluminum is designed to fully oxidize within the pulp, nor does it inherently address the specific recycling treatment and visual aluminum criteria.

4. "Northbox" by Cascades Inc.:

   • Description from Patent: This product uses aluminized layers, each between two layers of polymeric films, separated by a honeycomb paper structure. It aims for "pulper-safe" recycling, where the film/aluminum/film assembly is removed during repulping.
   • Issue Addressed by US11072148: The polymeric films significantly increase emissivity (0.20-0.70), preventing it from qualifying as a radiant barrier (emissivity ≤ 0.10). Additionally, the removed plastic films add substantial plastic waste to landfills. [cite: "the polymeric films used to protect the aluminum dramatically increase the emissivity, resulting in a product that—while being reflective to visual light—is not nearly as heat-reflective as bare aluminum, and simply does not qualify as a radiant barrier."]
   • Potential Anticipation (35 U.S.C. § 102): While this product describes a paper-containing, reflective insulation packaging, it does not anticipate the claimed emissivity of 0.10 or less, nor the critical feature where the aluminum layer fully oxidizes and remains within the repulped material without being visible or causing "stickies." Instead, its design is explicitly presented as being removed from the pulp.

Specific Patent Citations from IPR2025-01143 (as detailed in previous sections)

The IPR challenge for US11072148 cited the following patents. While the institution was denied on obviousness grounds, these references are still important for a comprehensive prior art discussion. A full § 102 analysis would require retrieving and detailing each of these documents.

1. EP 2,826,692 (D'Alessandro)

   • Publication/Filing Date: (Date would need to be retrieved from the full patent document or a database search.)
   • Brief Description (Inferred from IPR challenge context): Likely describes packaging materials or insulating structures, possibly involving metallic layers or recycled content. The IPR challenged obviousness, suggesting it has some overlap in elements or concepts.
   • Potential Anticipation (35 U.S.C. § 102): Without the full text of EP 2,826,692, it is difficult to state definitive anticipation. However, if D'Alessandro discloses a packaging with a paper layer, a polymer layer, and an aluminum layer (200nm or less) with emissivity ≤ 0.10, and this aluminum layer inherently becomes fully oxidized with no visible aluminum during the specific recycling treatment, it could anticipate one or more claims (e.g., Claims 1, 13, 25). The IPR's denial of institution suggests D'Alessandro, even in combination, did not sufficiently teach the full oxidation aspect.

2. US 2011/0177242 A1 (Schabacker)

   • Publication/Filing Date: (Date would need to be retrieved from the full patent document or a database search.)
   • Brief Description (Inferred from IPR challenge context): Likely pertains to packaging, insulation, or layered materials, potentially involving recyclable components or methods.
   • Potential Anticipation (35 U.S.C. § 102): Similar to D'Alessandro, if Schabacker discloses all elements of one of the independent claims (e.g., Claims 1, 13, 25, 26) in a single reference, including the specific thickness, emissivity, and post-recycling oxidation characteristics, it could anticipate. The IPR's outcome suggests it likely does not.

3. US 2017/0015182 A1 (Pettis)

   • Publication/Filing Date: (Date would need to be retrieved from the full patent document or a database search.)
   • Brief Description (Inferred from IPR challenge context): Likely addresses improvements in packaging, particularly with insulation properties, or potentially methods related to material processing or recyclability.
   • Potential Anticipation (35 U.S.C. § 102): As with the other IPR-cited patents, a full anticipation argument would require a detailed comparison of Pettis's disclosures against each element of US11072148's independent claims, especially the unique recyclability and full oxidation features. The IPR's denial of institution on obviousness grounds implies that this reference, alone or in combination, did not fully teach the claimed invention.

Conclusion on Anticipation

A direct anticipation under 35 U.S.C. § 102 requires that a single prior art reference discloses every element of a patent claim, arranged as claimed. Based on the patent's detailed discussion of the shortcomings of existing technologies and the specific outcome of the IPR, it is unlikely that any single piece of prior art fully anticipates the independent claims (1, 13, 17, 21, 25, 26) of US11072148, especially the unique combination of low emissivity (≤0.10) with a very thin aluminum layer (≤200nm) that fully oxidizes to become invisible and non-sticky after a defined paper recycling treatment, thus allowing the entire paper-containing packaging to be recycled as paper. Each category of prior art discussed by the patent text addresses some aspects (e.g., low emissivity, repulpability by weight, general layered structures) but fails to combine all the claimed features and overcome the specific problems addressed by US11072148. The IPR outcome further supports the non-anticipation of the claims by the cited patent art.