General Elec. Co. v. Hoechst Celanese Corp.

• Decision Date: 22 June 1990
• Docket Number: Civ. A. No. 87-458-JRR.
• Citation: 740 F. Supp. 305
• Parties: GENERAL ELECTRIC COMPANY, Plaintiff, v. HOECHST CELANESE CORPORATION and Celanese Engineering Resins Inc., Defendants.
• Court: U.S. District Court — District of Delaware

740 F. Supp. 305

GENERAL ELECTRIC COMPANY, Plaintiff, v. HOECHST CELANESE CORPORATION and Celanese Engineering Resins Inc., Defendants.

Civ. A. No. 87-458-JRR.

United States District Court, D. Delaware.

June 22, 1990.

COPYRIGHT MATERIAL OMITTED

David A. Anderson, of Potter, Anderson & Corroon, Wilmington, Del. (William F. Kilgannon, William J. Hone, and Stanley L. Amberg, of Davis, Hoxie, Faithfull & Hapgood, New York City, of counsel), for plaintiff.

Howard M. Handelman, of Bayard, Handelman & Murdoch, Wilmington, Del. (John F. Lynch, Michael Macklin, Glenn W. Rhodes, and Melinda L. Patterson, of Arnold, White & Durkee, Houston, Tex., of counsel), for defendants.

OPINION

ROTH, District Judge.

General Electric Company ("GE") filed this action alleging infringement of U.S. Patent No. 3,953,394 ("the GE patent") against Hoechst Celanese Corporation ("HCC") and Celanese Engineering Resins, Inc. ("CER"). HCC and CER have each counterclaimed for a declaration of non-infringement, invalidity and unenforceability of the GE patent.

On November 9, 1988, the Court ruled on two summary judgment motions which had been filed by the defendants, holding that claims 1-37, 39 and 40 were not infringed by HCC, that claims 31-37, 39 and 40 were invalid, and that the remaining assertions could not be resolved on summary judgment. See General Electric Co. v. Hoechst Celanese Corp., 698 F.Supp. 1181 (D.Del.1988) (hereinafter "General Electric I").

Presently before the Court are three new summary judgment motions filed by the defendants regarding (1) invalidity of claims 1-4 and 38 of the GE patent under 35 U.S.C. § 102(b); (2) invalidity of all claims on the grounds of undue breadth, which renders the claims invalid under 35 U.S.C. §§ 102, 103 or § 112; and (3) nonliability on the grounds of laches.

FACTS

The following undisputed facts of record are relevant to all three summary judgment motions.

The GE Patent

GE is the owner of U.S. Patent No. 3,953,394, entitled "Polyester Alloys and Molding Compositions Containing the Same." GE applied for the GE patent on November 15, 1971. The patent was issued in 1976 and reexamined in 1986-1987. GE's original patent described:

thermoplastic, stable, blended compositions comprising in combination

a. from about 1 to about 99 parts by weight of a poly(ethylene terephthalate) resin referred to as "PET" and

b. from about 99 to about 1 part by weight of a poly(1,4-butylene terephthalate) resin referred to as "PBT" or a copolyester thereof with a minor amount of an aliphatic or aromatic dicarboxylic acid or an aliphatic polyol.

(D.I. 111A at A3) PET and PBT are both polymers, known as polyesters, which contain an ester functional group as part of the repeating unit in the polymer. In PET, the repeating unit is ethylene terephthalate; in PBT, the repeating unit is butylene terephthalate.

PET and PBT can be combined in different ways. Under some conditions a mixture of PET and PBT results in a "copolyester" (also referred to as a "copolymer"). A copolyester of PET and PBT has both ethylene terephthalate units and butylene terephthalate units chemically combined in a single polymer chain. One method of forming a copolyester of PET and PBT is to combine the two copolymers in a melt and allow a reaction ("transesterification") to proceed. As a result of the transesterification reaction, polymer chains having both "ET" and "BT" units are formed. Alternatively, PET and PBT can be combined in a blend or mixture in such a way that a transesterification does not occur. One method of achieving this is to combine PET and PBT in a melt, as is done when forming a copolymer, but to retard or prevent the occurrence of a transesterification by adding a phosphorous compound to the melt at or before mixing. (D.I. 111A at A30 ¶ 8)

The novelty and objective of the compositions claimed by the GE patent is explained in the patent specification as follows:

Because PET is known to crystallize only very slowly from the melt and PBT is known to crystallize very rapidly from the melt, in view of the above, it would be entirely unexpected to find that blends of these two resins prove to be highly compatible both on the macro and molecular scale. In other words, these two polyester resins, which should be incompatible on the basis of the wide difference in their rates of crystallization, have, in fact, been discovered to form a stable alloy.

. . . . .

It is an object of this invention to improve the moldability of PET while improving the properties of PBT and to provide compositions having many properties improved over those compositions containing either resin alone.

(Id. at A2, col. 2, lines 17-27, 63-69)

The Reexamination

The GE patent was reexamined in 1986-1987. The Patent Examiner ordered reexamination in light of British Patent No. 1,060,401, entitled "Method of Manufacturing Stable Block Copolyesters and Polyester Mixtures," hereinafter "Kurashiki" and Belgian Patent No. 747,243, entitled "Elastic Polyester Fibers." hereinafter "Fiber" (D.I. 111A at A35, A41) Kurashiki was published on March 1, 1967 and Fiber was published September 14, 1970.

The invention of Kurashiki relates to "stable compositions containing block copolyesters or polyester mixtures containing at least two polyesters." (D.I. 111A at A35, lines 9-11) The principal object of the Kurashiki invention, as stated in the patent, "is to manufacture stable block copolyesters ... or polyester mixtures which can exist as stable mixtures without causing chemical combination of the two or more polyesters." (Id. at A35 lines 16-26) A further object of the Kurashiki invention is to "provide a method of manufacturing ... shaped articles from block copolyesters or polyester mixtures having improved ... mouldability...." (Id. at A35 lines 27-31) Kurashiki recognizes that "it is difficult to obtain a polyester mixture wherein two or more than two kinds of polyesters are not chemically combined with each other owing to the fact that there occurs the ester interchange reaction when the mixture is heated." (Id. at A35 lines 63-68) Yet Kurashiki discloses that this difficulty can be overcome: "If two or more than two kinds of polyesters are heated in the presence of the A-material a phosphorous-containing compound which acts as a catalyst inhibitor, a substantially stable block copolyester or a polyester mixture wherein two polyesters are not substantially chemically combined together with each other can be obtained." (Id. at A36 lines 18-26) Example 4 of the Kurashiki patent describes a combination of 78 parts PET by weight to 22 parts PBT. (Id. at A38 lines 35-46)

The British Patent Office issued an abridgment of the Kurashiki patent in 1966-1967. The abridgment discloses mixtures of PET and PBT, and states that "a polyester mixture or block copolymer is stabilized by adding ... a phosphorous compound which retards or prevents esterinterchange." (D.I. 216A at A19) Fiber describes a process whereby 50 parts PET and 50 parts PBT are combined and extruded through an annular nozzle at an outlet temperature of 275°C. (D.I. 111A at A59)

On reexamination, GE argued to the Examiner that the GE patent was distinguishable from these prior art references because the references claimed compounds that contained copolymers of PET and PBT, rather than a blend of substantially unreacted PET and PBT as called for in the GE Patent. (Id. at A81) The Examiner did not accept GE's argument. He noted that the terminology of the GE patent was not limited to "blends," and that blends of PET and PBT made under the conditions of GE's original patent inevitably contain small amounts of block copolymer. (D.I. 152A at A76-A77) The Examiner concluded that:

The claim terminology, when reasonably interpreted, encompasses blended compositions which may comprise various components, including blocked copolymer material, as well as the two recited linear polymers. The other components may be in major amounts. The composition blended with all components is a blended composition. Hence, a blended composition as encompassed by the claims may include major proportions of block polymeric materials.

The Examiner rejected the GE patent on November 17, 1986, "under 35 U.S.C. 103 as being unpatentable over Kurashiki and Fiber...." (Id. at A75)

Shortly thereafter, representatives of GE met with the Examiner to discuss limiting the GE claims. GE proposed amending its claims from "comprising" PET and PBT, to "consisting essentially of" PET and PBT. (Id. at A86)¹ This change in claim terminology would avoid prior art by eliminating copolymer from the claimed blend. The Examiner requested that "objective evidence and discussion would be necessary to ... show that what is being eliminated block copolymer would alter the basic nature of the compositions desired to be claimed." (Id. at A82) Thus, the Examiner requested GE to narrow its claims and to show that the compositions covered by the narrowed claims had basic and novel characteristics different from mixtures which contained the prior art copolymer along with the linear polymers.

GE amended its claims to incorporate the "consisting essentially of" terminology, and conducted an experiment which compared the moldability of a PET/PBT copolymer set out in Kurashiki with that of GE's claimed "blend." GE submitted the following summary of its test results in support of its amended claims:

Sample A-C bars were made by injection molding at a temperature of 170°F with a mold cycle of 30 seconds to produce a bar one quarter inch (¼") thick.

In contrast to the uniformly milky, nondistorted bar of sample C, which bar was prepared from the claimed blend of PET and PBT, Samples A Kurashiki and B Kurashiki/GE mix were badly distorted and non uniform in that the edges of the bar are semi-transparent and milky only in the center.

. . . . .

It is urged that the experimental evidence submitted herewith overwhelmingly establishes that a copolymer of PET and

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