HB Fuller Co. v. National Starch and Chemical Corp.

• Decision Date: 21 June 1988
• Docket Number: Civ. No. 4-85-1632.
• Citation: 689 F. Supp. 923
• Parties: H.B. FULLER CO., Plaintiff, v. NATIONAL STARCH AND CHEMICAL CORP., Defendant.
• Court: U.S. District Court — District of Minnesota

689 F. Supp. 923

H.B. FULLER CO., Plaintiff, v. NATIONAL STARCH AND CHEMICAL CORP., Defendant.

Civ. No. 4-85-1632.

United States District Court, D. Minnesota, Fourth Division.

June 21, 1988.

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Alan D. Carlson, Mark D. Schuman, Merchant, Gould, Smith, Edell, Welter & Schmidt, P.A., Minneapolis, Minn. (Susan F. Marrinan, H.B. Fuller Co., St. Paul, Minn., of counsel), for plaintiff.

Charles Quaintance, Jr., Maslon, Edelman, Borman & Brand, Minneapolis, Minn., Stephen B. Judlowe, William G. Todd, Porter F. Fleming, Hopgood, Calimafde, Kalil, Blaustein & Judlowe, New York City (Louis J. Virelli, Nat. Starch and Chemical Corp., Bridgewater, N.J., of counsel), for defendant.

MEMORANDUM AND ORDER INCORPORATING FINDINGS OF FACT AND CONCLUSIONS OF LAW

MacLAUGHLIN, District Judge.

I. BACKGROUND

Plaintiff H.B. Fuller Co. (Fuller) is a corporation organized and existing under the laws of the State of Minnesota, having its principal place of business in St. Paul, Minnesota. Defendant National Starch & Chemical Corporation (National) is a corporation organized and existing under the laws of the State of Delaware, having its principal place of business in Bridgewater, New Jersey. Fuller commenced an action for a declaratory judgment of patent invalidity and non-infringement, arising under 28 U.S.C. ?? 2201, 2202 and 1338. Fuller asserted two grounds for invalidity of the patent: obviousness and inequitable conduct. National responded to Fuller's complaint, filing a counterclaim alleging patent infringement. By stipulation of the parties prior to trial, Fuller dropped its claim of obviousness and the parties proceeded to trial before the Court on the issues of inequitable conduct, infringement and damages.

The patent in suit is United States Letters Patent No. 4,526,577 (the '577 patent). Plaintiff's Exhibit 10. The '577 patent issued July 2, 1985. The inventors are Robert Schmidt and Paul Puletti. Schmidt is employed as project supervisor, hot melt development for National. Puletti is director of product development for National but at the time the product underlying the '577 patent was developed he served as manager of hot melt development. National is assignee and record owner of the '577 patent.

The '577 patent relates to disposable articles prepared using multi-line construction and to hot melt adhesives useful for the assembly thereof. The '577 patent discloses and claims a multi-line constructed disposable diaper (or in some claims, disposable articles generally) in which the various diaper substrates are bonded by specific adhesive compositions based upon A-B-A block or A-B-A-B-A-B multi-block copolymers, where the A component is styrene and the B component is butadiene in stated ranges, together with various other chemical constituents.¹ In general, disposable diapers are composed of a polyethylene or polypropylene outside sheet and inner absorbent material covered by an inner liner of non-woven tissue. Adhesives such as the type described in the '577 patent are used to bind these inner and outer layers together. Multi-line or fine line construction is an assembly using a number of thin lines of adhesive to adhere the outer polyethylene sheet to the batted, non-woven fluid absorbent layer and to the inner tissue. The adhesive is applied in the form of very fine parallel longitudinal strips or in a "multi-dot" pattern of application, requiring the use of a large number of adhesive deposits, each deposit being of a very small quantity of adhesive.

In order to be commercially acceptable a multi-line adhesive must possess certain physical properties. For example, the adhesive must possess a high degree of adhesion since it is applied in the form of a number of very fine parallel longitudinal strips thus requiring each line to possess exceptionally high bonding properties. The adhesive must also possess sufficient adhesive and cohesive strength to provide high bond strength values when subjected to stress so the constructions cannot be easily separated. It is necessary that the adhesive, upon application, not absorb through the actual disposable construction and that the adhesive bonds not only remain secure but also be flexible even after prolonged periods of storage. In addition to requiring heat and oxidation resistance on aging they must also possess sufficient bonding range and must be white or clear in color. See '577 Patent Col. 1, lines 1940. Further, the adhesive must withstand high mixing and application temperatures without degrading and sacrificing necessary adhesive properties. Prior to the development of the adhesive described in the '577 patent the primary adhesives sold and used for multi-line diaper construction were plastic-based adhesives whose main components were ethylene vinyl acetate (EVA) copolymers or atactic polypropylene (APP) copolymers. Although suitable for multi-line construction, EVA and APP adhesives in some respects fell short of the desired physical specifications.

The disposable diaper industry in the United States was and is big business. In 1983, disposable diaper sales were more than $2 billion at wholesale.² As such, a great financial incentive existed for adhesives manufacturers to develop an improved diaper adhesive which would capture the market. To this end, Puletti and Schmidt set about formulating an adhesive that would satisfy all the strict technical requirements for multi-line diaper construction. Their experimentation yielded fruit with the formulation in March-April 1983 of a hot-melt pressure sensitive adhesive based on an A-B-A-B-A-B multi-block copolymer with styrene endblocks and butadiene midblocks. National successfully tested the new adhesive system in the laboratory and on disposable diapers. Thereafter, Schmidt, Puletti and National patent agent Ellen Dec prepared a patent application which later issued as the '577 patent.

II. PATENT PROSECUTION

On January 9, 1984 National filed with the Patent and Trademark Office (PTO) the patent application (Serial No. 569,001) which later issued as the '577 patent. The application was prepared by National patent agent Ellen Dec in conjunction with Schmidt and Puletti. As originally filed, the application included fifteen claims which recited a fully-constructed disposable diaper using S-B-S or S-EB-S adhesive. See Plaintiff's Exh. 24 at 17-20. On July 23, 1984 the PTO (patent examiner James C. Cannon) issued a First Office Action which rejected all fifteen claims as unpatentable. The basis for the patent examiner's ruling of unpatentability was his finding that the claimed invention would have been obvious to one of ordinary skill in the art in light of the disclosures of the Puletti (No. 4,419,494) and Harlan (No. 3,239,478) patents. The examiner's notes state:

Puletti discloses that hot melt A-B-A copolymer compositions are useful as adhesives for PE layers used in the production of disposable diapers.

Harlan teaches that pressure-sensitive, hot melt adhesive compositions reading on those of the above-rejected claims have utility as adhesives for PE films and non-woven fabrics.

In view of the known practice of using hot melt A-B-A copolymers as adhesives for PE layers used in disposable diapers (Puletti) and the known utility of applicants' compositions as adhesives for PE films and non-woven fabrics (Harlan), it is not seen that at the time of applicants' invention it would have been unobvious to one of ordinary skill in the art to have used the hot melt, pressure-sensitive adhesives of Harlan to adhere a PE non-woven layer to a PE film layer in the production of disposable diapers.

Plaintiff's Exh. 24 at 45.

Thereafter, Dec, Schmidt and Puletti prepared an amendment to the patent application, which amendment was submitted to the patent examiner October 17, 1984. Claim 1 of the patent was amended to more specifically define the block copolymer, and further argument was offered in support of National's claim of patentability. In brief, in their amendment National argued that while Puletti and Harlan described A-B-A type block copolymer adhesives suitable for bonding a multitude of substrates, they were not directed to or suitable for the specific end use identified by the '577 patent, i.e., multi-line construction. National contended that, due to the breadth in scope of the Harlan and Puletti patents, they offered "little or no suggestion to the artisan that a limited number of compositions within their scope might be employed for this very specific end use." Plaintiff's Exh. 24 at 50.³ National further contended that because the '577 patent was directed toward a specific end use, and the '577 patent overcame the physical deficiencies inherent in other copolymer-based adhesives, it was not obvious to one of ordinary skill in the art and did constitute a significant advance over and above the teachings of Harlan and Puletti.

Following review of the amendment, the patent examiner issued an amended Office Action approving issuance of the '577 patent. The examiner's amendment is dated March 25, 1985, and states:

The specificity of applicants' application of adhesive, the breadth of the Puletti and Harlan disclosures, and the non-utility of many of the adhesives disclosed in said references for applicants' purposes are convincing of the patentability of applicants' claims over the Puletti and Harlan disclosures.

Plaintiff's Exh. 24 at 54. Accordingly, the patent issued July 2, 1985.

Since its development, National has manufactured and sold the adhesive described in the '577 patent under the designation "adhesive composition 34-2881" to various manufacturers of disposable diapers. This product, along with similar S-B-S adhesives sold by National, has enjoyed substantial commercial success. In fact, as of the time of trial, sales to Kimberly Clark alone were approximately one million pounds per month. Furthermore, National has...