PTAB

IPR2014-01245

Wintek Corp v. TPK Touch Solutions Inc

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Method of Forming Touch Sensing Circuit Pattern
  • Brief Description: The ’935 patent discloses a method for manufacturing a touch sensing circuit pattern. The method involves sequentially forming parallel first axial conductive lines, insulation barriers over those lines, and then second axial conductive lines and associated electrodes on a transparent substrate.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1 and 5 by Sugimoto

  • Prior Art Relied Upon: Sugimoto (Japanese Published Patent Application No. JP 58-171573).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Sugimoto discloses a method for forming a touch panel structure that meets every limitation of independent claims 1 and 5. Sugimoto’s method begins by forming transverse "mother lines X" (first axial conductive lines) on a transparent substrate. Next, it forms insulating material over the X lines (insulation barriers). Finally, it forms longitudinal "mother lines Y" (second axial conductive lines) and detection electrodes 2 and 3. Petitioner asserted this process directly maps to the sequential steps recited in the challenged claims.

Ground 2: Obviousness of Claims 3-4, 7-10, 12-14, 17-19, and 21-28 over Sugimoto and Chang

  • Prior Art Relied Upon: Sugimoto (Japanese Published Patent Application No. JP 58-171573) and Chang (Japanese Published Patent Application No. JP U3134925).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner contended that Sugimoto teaches the foundational method of creating the touch sensor layout, as detailed in Ground 1. For limitations not explicitly in Sugimoto, such as using sputtering or transparent conductive materials like Indium Tin Oxide (ITO), Petitioner pointed to Chang. Chang allegedly described sputtering as a conventional method for applying conductive materials (e.g., ITO) to form touch pattern structures. It also taught the inclusion of "second directional lines" to carry signals from the electrodes to control circuitry, a feature Petitioner argued was necessary for any functional touch panel.
    • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Sugimoto’s basic layout with Chang’s conventional manufacturing techniques. The motivation would be to implement a well-known, functional design by using standard processes like sputtering for efficiency and adding necessary transmission lines to make Sugimoto's disclosed structure operational.
    • Expectation of Success: A POSITA would have had a high expectation of success because combining these elements involved applying known techniques (sputtering from Chang) to a standard touch panel architecture (from Sugimoto) to achieve a predictable result.

Ground 3: Obviousness of Claims 1, 3-5, 7-10, 12-14, 17-19, and 21-28 over Wu and Chang

  • Prior Art Relied Upon: Wu (Chinese Patent Application No. CN 101131492 A) and Chang (Japanese Published Patent Application No. JP U3134925).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner presented this combination as an alternative to the Sugimoto-based grounds. Wu was said to disclose a touch panel manufacturing method that followed the same basic sequence of forming first conductive lines, an insulating layer, and then second conductive lines and electrodes. However, Wu’s method created a full sheet of insulating material, which required forming vias to connect different layers. Chang, in contrast, taught an improved method of forming distinct, separated "islands" of insulation only where conductive lines cross.
    • Motivation to Combine: A POSITA would have been motivated to modify Wu’s method by incorporating Chang’s technique of using insulation islands. Chang explicitly touted this approach as a solution to problems with prior art methods like Wu's, stating that it results in a thinner and lighter structure, simplifies the manufacturing process, reduces costs, and increases yield by eliminating the need for vias.
    • Expectation of Success: The combination was presented as a predictable substitution of one known insulation technique (full sheet with vias from Wu) for an improved one (islands from Chang) to achieve the well-documented benefits described in Chang. This would have been a straightforward design choice for a POSITA.

  • Additional Grounds: Petitioner asserted additional obviousness challenges based on combinations of Sugimoto, Chang, Wu, Binstead (Patent 6,137,427), and Bolender (Application # 2005/0030048). These grounds added Binstead to teach the use of "metal" for transmission lines and Bolender to teach the "concurrent forming" of multiple structures to further support obviousness arguments for specific claim limitations.

4. Key Claim Construction Positions

  • Petitioner dedicated significant argument to the construction of terms related to manufacturing steps. In a prior related case (IPR2014-00141), the Board construed the claims as requiring the overall manufacturing steps (e.g., forming lines, then barriers, then electrodes) to be performed in the recited order.
  • While deferring to that sequential construction for the overall steps, Petitioner argued that terms like "forming" or "sputtering" multiple structures within a single step (e.g., "forming two separated first axial electrodes, two separated second axial electrodes and a second axial conductive line") do not require that those internal structures be created simultaneously or in any particular order relative to one another. Petitioner asserted this position was critical because the prior art often forms these structures in different sequences or at different times within a single broader manufacturing stage.

5. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1, 3-5, 7-10, 12-14, 17-19, and 21-28 of the ’935 patent as unpatentable.