The opinion of the court was delivered by: MCCURN
MEMORANDUM-DECISION AND ORDER
This action, brought by plaintiff T.J. Smith & Nephew Limited (Smith & Nephew) against defendants Consolidated Medical Equipment, Inc. (Con Med) and Avery International Corporation (Avery) charges the defendants with infringement of the plaintiff's Reissue Patent No. Re 31,887 (the '887 reissue patent). The court has jurisdiction of the action pursuant to 28 U.S.C. § 1338(a).
Currently pending before the court is the plaintiff's motion for a preliminary injunction seeking to enjoin the defendants from manufacturing and marketing two products which allegedly infringe the '887 reissue patent. On September 11 and 12, 1986 a hearing was held during which expert witnesses for both sides testified in support of and in opposition to the motion. The court has carefully considered the evidence before it, and the following constitutes its findings of fact and conclusions of law in accordance with Fed. R. Civ. P. 52(a).
Plaintiff Smith & Nephew is a British corporation that was assigned Patent No. 3,645,835 (the '835 patent) on February 29, 1972. The '835 patent dealt with "moisture-vapour-permeable pressure sensitive adhesive materials." On June 6, 1980, the plaintiff filed an application for the reissue of the '835 patent and on May 14, 1985 was granted the '887 reissue patent. Upon being granted the reissue patent, the plaintiff surrendered the original patent. The '887 reissue patent, like the '835 patent, deals with, among other things, "moisture-vapour-permeable pressure sensitive adhesive materials." The plaintiff manufactures a product marketed under the brand name "OpSite," a wound dressing that utilizes the above-mentioned materials in it construction.
Defendant Con Med is a New York corporation that, since 1983, has marketed wound dressings under the brand names Veni-Gard and Derma-Shield. Co-defendant Avery is a Delaware corporation that manufactures "moisture-vapour-permeable pressure sensitive adhesive materials" and sells them to Con-Med, among other companies, for its use in the Veni-Gard and Derma-Shield products. Avery has agreed to indemnify Con Med for any damages awarded against it resulting from patent infringement litigation.
The plaintiff alleges that Con Med's wound dressings infringe Claim 12 of the '887 reissue patent, which provides:
A moisture-vapour-permeable pressure-sensitive adhesive material for use on animal skin and nails, comprising a backing material which is an unreinforced thermoplastic polyurethane film having a pressure-sensitive adhesive on at least substantially the whole of the body-adhering portion of at least one surface of said backing material, both said backing material and said adhesive being moisture-vapour-permeable and unaffected by water and both said backing material and said adhesive comprising a synthetic polymer and being continuous and nonpermeable to liquid water, said adhesive material having a moisture Vapor permeability of at least 300 g./sq. meter/24 hours/40 degrees C./80 RH.
During the evidentiary hearing, the court's attention was directed primarily to three elements of the claim. The plaintiff has alleged that the backing material on the alleged infringing products is unreinforced, that the backing material and adhesive on the products is unaffected by water, and that the backing material and adhesive are continuous as defined in the patent.
Of the above three elements in dispute, the parties devoted the least effort to the issue of whether the backing material on the alleged infringing products is unreinforced. The plaintiff' expert stated unequivocally, although without full explanation, that the backing material on the products is unreinforced. The defendants' expert witness testified that the backing material is reinforced in at least two ways. The Veni-Gard wound dressing contains foamed plastic reinforcements that surround the backing layer. Further, both Veni-Gard and Derma-Shield utilize a transfer sheet which, according to the expert, reinforces the backing layer and allows the dressing to be applied. At this juncture, the court has an insufficient basis to determine whether the backing material on the Veni-Gard and Derma-Shield products is unreinforced.
As to the next element of the claim under consideration, the plaintiff asserts that neither its product nor the defendants' products contain a backing material or an adhesive that is affected by water. The defendants maintain that the adhesive on the products is in fact affected by water. To demonstrate their point during the hearing, one of the defendants' experts conducted the "rolling tack ball" test for the court. The witness cut a strip of the adhesive manufactured by Avery for us in the Con Med products and laid it flat face-up on a table. A ball bearing was then rolled down an incline onto the adhesive, where the adhesive stopped its forward progress before it travelled more than an inch or two from the bottom of the incline.
The adhesive was then sprayed with water, and the excess water was wiped off. The ball bearing was again rolled down the incline and onto the adhesive, but this time, it did not stop an continued to roll off the table. Thus, the defendants argue, the adhesive is very much affected by water.
The plaintiff's expert challenged this test in two ways. First, he stated that under the circumstances that these product are normally used, that is, with the wound dressings attached to the skin, the adhesive would not come into direct contact with water and would not be affected by it. Second and more convincing was the expert's assertion that the adhesive would again be tacky as soon as the water dried. The court did observ that very shortly after the "rolling tack ball" test was conducted, the adhesive apparently regained all of the tackiness that it possessed before it was sprayed with water. The plaintiff's expert stated ...