PTAB

IPR2015-01309

Mexichem Amanco Holding Sa De CV v. Honeywell Intl Inc

Log In
Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Compositions Containing Fluoroalkenes and Carbon Dioxide
  • Brief Description: The ’808 patent discloses heat transfer compositions comprising a blend of carbon dioxide (CO2) and one or more hydrofluoroolefin (HFO) compounds defined by a specific chemical formula. The compositions are presented as useful replacements for older refrigerants and are intended for applications such as refrigeration systems, blowing agents, and propellants.

3. Grounds for Unpatentability

Ground 1: Claims 1-5, 10, and 16-19 are obvious over Kruse in view of Inagaki.

  • Prior Art Relied Upon: Kruse (German Application DE4116274), Inagaki (Japanese Application JP-04-110368).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that independent claim 1, which recites a composition of about 1-40% CO2 and 60-99% of a specific HFO, is rendered obvious by the combination. Kruse taught refrigerant mixtures containing CO2 and saturated hydrofluorocarbons (HFCs) in a broad range (1-99% CO2) to serve as environmentally safer replacements for chlorofluorocarbons (CFCs). Inagaki taught using specific unsaturated HFCs (HFOs), including HFO-1234ze and HFO-1234yf which fall under the patent’s Formula I, as heat transfer fluids that were also replacements for CFCs. Petitioner contended the combination of Kruse’s CO2 mixture concept with Inagaki’s specific HFOs disclosed every limitation of claim 1. Dependent claims reciting specific HFOs (claims 2-4) were allegedly met directly by Inagaki’s examples, and the vapor pressure limitations were argued to be inherent properties of such compositions.
    • Motivation to Combine: A person of ordinary skill in the art (POSITA) would combine the teachings because both Kruse and Inagaki addressed the same problem: finding effective, environmentally friendly replacements for CFC refrigerants. A POSITA would have been motivated to substitute the known unsaturated HFOs from Inagaki for the saturated HFCs in Kruse’s CO2 mixtures to achieve a refrigerant with desirable performance characteristics and a low global warming potential.
    • Expectation of Success: A POSITA would have had a reasonable expectation of success because both references taught that their respective components functioned effectively as refrigerants and heat transfer fluids, suggesting their combination would perform predictably for the intended purpose.

Ground 2: Claims 1-5, 10, 12-14, and 16-19 are obvious over Inagaki in view of Kruse and further in view of Butler.

  • Prior Art Relied Upon: Kruse (German Application DE4116274), Inagaki (Japanese Application JP-04-110368), and Butler (Patent 3,723,318).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground relied on the same core combination of Kruse and Inagaki as Ground 1 but added Butler to reinforce the motivation to combine. Butler expressly taught compositions of an unsaturated HFO (trifluoropropene) combined with CO2 for use as refrigerants and propellants. The weight percentage ranges disclosed in Butler (1-91% trifluoropropene, balance CO2) overlapped with the ranges claimed in the ’808 patent.
    • Motivation to Combine: Petitioner argued that Butler demonstrated it was already well-known in the art to combine unsaturated HFOs with CO2 for refrigeration. This teaching removed any doubt that a POSITA would have been motivated to combine the specific HFOs of Inagaki with the CO2 mixtures of Kruse. Butler provided an explicit roadmap for creating the claimed invention, further strengthening the obviousness rationale.

Ground 3: Claim 6 is obvious over Kruse in view of Inagaki and further in view of Bivens.

  • Prior Art Relied Upon: Kruse (German Application DE4116274), Inagaki (Japanese Application JP-04-110368), and Bivens (Patent 6,783,691).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground targeted claim 6, which depends from claim 5 and adds a limitation requiring the composition to include a lubricant selected from a specific list, including polyol esters (POEs) and polyalkylene glycols (PAGs). Petitioner established the base composition as obvious via Kruse and Inagaki. Bivens was introduced to teach the selection of a suitable lubricant. Bivens disclosed that POEs and PAGs are the preferred lubricants for HFC-based refrigeration systems.
    • Motivation to Combine: A POSITA, having arrived at the obvious refrigerant composition from Kruse and Inagaki, would have needed to select a compatible lubricant for use in a practical system. Petitioner asserted it would have been an obvious and routine step to consult the art and select a known, suitable lubricant. Bivens provided the explicit teaching that POEs and PAGs were preferred for this exact class of refrigerants.
    • Expectation of Success: Because Bivens taught that POEs and PAGs were commonly and successfully used with HFCs, a POSITA would have had a high expectation of success in using them with the closely related HFO compositions.
  • Additional Grounds: Petitioner asserted numerous additional obviousness challenges, including grounds for claims 7-9 (blowing agents) relying on Corr (Patent 6,384,095), grounds for claims 12-14 (sprayable propellants) relying on Schultz (Patent 7,105,152), and a ground for claim 15 (sterilization method) relying on Nimitz (Patent 5,674,451). These grounds followed a similar logic of combining the base refrigerant composition of Kruse and Inagaki with additional art teaching the specific claimed application.

4. Key Claim Construction Positions

  • Petitioner argued for a construction of the term "C2 unsaturated, substituted, alkyl radical" as recited in Formula I of the claims. This construction was central to mapping the prior art. Petitioner contended the term should be interpreted to include any carbon group with two carbons connected by a double or triple bond, allowing for attachment to the rest of the formula's structure. This construction explicitly covered compounds like HFO-1234ze (CF3CH=CHF) and HFO-1234yf (CF3CF=CH2), which were the primary HFOs disclosed in the Inagaki reference.

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-19 of Patent 8,623,808 as unpatentable.