538 F.2d 453 (1st Cir. 1976), 75-1373, International Tel. & Tel. Corp. v. Raychem Corp.

Docket Nº:75-1373.
Citation:538 F.2d 453
Case Date:June 25, 1976
Court:United States Courts of Appeals, Court of Appeals for the First Circuit

Page 453

538 F.2d 453 (1st Cir. 1976)

191 U.S.P.Q. 1


Plaintiff, Appellant,


RAYCHEM CORPORATION, Defendant, Appellee.

No. 75-1373.

United States Court of Appeals, First Circuit

June 25, 1976

Page 454

John R. Hally, Boston, Mass. for plaintiff, appellant.

W. R. Hulbert, Boston, Mass., for defendant, appellee.

Before COFFIN, Chief Judge, and McENTEE and CAMPBELL, Circuit Judges.

COFFIN, Chief Judge.

Plaintiff-appellant International Telephone and Telegraph Corporation (ITT) filed this declaratory judgment action for an adjudication of invalidity and noninfringement of U.S. Patent No. 3,269,862, entitled "Crosslinked Polyvinylidene Fluoride over a Crosslinked Polyolefin", issued on August 30, 1966 in the names of Vincent K. Lanza and Edward C. Stivers (Lanza Patent). Defendant Raychem Corporation (Raychem), assignee of the Lanza Patent, counterclaimed for infringement. After a bench trial, the district court found the patent to be valid and infringed by ITT.

On appeal, ITT claims that the district court erred as a matter of law upon the issue of obviousness under 35 U.S.C. § 103, and that it made clearly erroneous findings of fact bearing upon that issue. Further, it challenges the court's determination that the patent complied with the "best mode" disclosure requirement under 35 U.S.C. § 112. The final issue is whether the district court erred in finding that the patentees had not committed fraud by failing to disclose information to the Patent Office.

The patent in suit describes a wire insulation composed of a primary layer of a crosslinked polyolefin, such as crosslinked polyethylene, and a secondary, outer layer of crosslinked polyvinylidene fluoride (referred to hereinafter by its trade name, Kynar). 1 The wire insulation claimed in the patent

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may contain antimony oxide in the polyethylene layer. Wire constructed within the claims of the patent is particularly suitable for use on high performance jet aircraft to carry electricity to various parts of the airplane, and to transmit electronic signals for the extensive electronic equipment used on the plane. This wire has been qualified for Defense Department aircraft under Military Specification Mil-W-81044. Accordingly, it is referred to in the trade as 44 wire.

Military specifications are prepared by the government in consultation with the contractors who build the aircraft. The specifications set forth a number of performance characteristics in addition to electrical insulation. A wire must satisfy each of the performance standards before it can be used pursuant to the specification. The characteristics needed for aircraft wire include: (1) low flammability; (2) solvent resistance (so that gas leaks will not degrade the wire); (3) abrasion resistance; (4) flexibility; (5) processability (capacity of a wire to be stripped, marked or sealed); and (6) notch insensitivity (capacity of a wire to be nicked and bent without cutting through the entire depth of insulation). Two other characteristics are of particular importance to this case: low weight and a specified "temperature rating", i. e., the highest temperature at which a wire has a useful service life of 10,000 hours. For each of the foregoing characteristics, tests have been devised which indicate the wire's standard of performance. A military specification will list the standards of performance necessary to qualify a wire under it.

The wire described in the patent in suit was developed for use in the F-111 fighter plane. General Dynamics, the contractor in charge of the Air Force version of that plane, initiated a search for a light weight, medium temperature rated aircraft wire. In response, Raychem began experimentation with a number of possible wire constructions. The types of constructions it attempted, however, were limited by the technology in which the company specialized. The principal technology of Raychem (the name is a contraction of Radiation Chemistry) is the combination of advanced polymeric and radiation techniques.

There was testimony before the district court establishing that there were between 50 and 75 polymeric materials available as insulating material for wire. Raychem had previously produced insulation using polyethylene, a material known to have good electrical insulation properties. However, polyethylene had a low temperature rating, poor solvent resistance, and a number of other undesirable characteristics. As was well known in the trade, these properties could be improved by placing a secondary or outer layer of insulation over the polyethylene. But there was no universal material which was good for all the desired characteristics of acceptable airplane wire. Further, interactions between the materials made prediction of the characteristics of a combined insulation difficult. For example, Raychem had previously experimented with a Teflon protective layer over polyethylene. This insulation burst when internal pyrolysis of the polyethylene emitted gasses which could not escape through the Teflon. In developing the wire in suit for General Dynamics, Raychem considered thick-walled crosslinked polyethylene, polyethylene with glass fillers, crosslinked Kyner over polyethylene, fluorinated theylene propylene rubber over crosslinked polyethylene, Kynar over polyvinylchoride and others.

Of the materials tried, the crosslinked Kynar over crosslinked polyethylene combination was the only one to give any indication of satisfying the General Dynamics requirements. Tests were performed to determine whether that wire construction could meet all the proposed standards. The

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district court found that these tests had some unexpected and surprising results. First, the test for a temperature rating resulted in an unprecedented phenomenon. Because testing a wire for 10,000 hours would be prohibitively time consuming, the government developed, and the industry used, a short period-high temperature test to predict a temperature rating for 10,000 hours. The actual measurements would be plotted on a graph, and a straight line extended from the plots to determine the temperature at which the wire would have a service life of 10,000 hours. Under the initial tests there were indications that crosslinked Kynar over crosslinked polyethylene would fail to meet the required 135o C temperature rating. Further testing, however, showed that the graph of the time-temperature results had a dog-leg. This dog-leg raised the prediction of the temperature at which the wire would have a service life of 10,000 hours, to 135o C.

The addition of antimony oxide to the polyethylene layer resulted in another surprise. That construction met the ash formation requirement of the flammability test which General Dynamics set down for the replacement wire, and was exceptionally flame retarding. Antimony oxide had not been previously used alone as a flame retardant, although it had been used in combination with other additives. To account for this unexpected performance, Raychem proposed a theory in its patent application that the Kynar outer layer provided an oxygen barrier. This theory has since been discarded. Raychem now suggests that a chemical combination occurs between the antimony oxide and the hydrogen fluoride that is released from the Kynar when the wire is subject to heat. The resulting antimony fluoride compounds, Raychem claims, are flame retardants.

Raychem proposed the wire to General Dynamics, and after further testing it was accepted under Mil-W-81044 for use on the F-111 aircraft. It...

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