Full opinion text
AUSTIN, District Judge. FINDINGS OF FACT AND CONCLUSIONS OF LAW PARTIES, PLEADINGS AND ISSUES 1. Plaintiff, Ransburg Electro-Coating Corp., is a corporation incorporated under the laws of the State of Indiana and has its principal office and place of business at 3939 West 56th Street, Indianapolis, Indiana. (Amended Complaint para. II, and Amended Answer para. 2.) 2. Defendant, Nordson Corporation, is a corporation incorporated under the laws of the State of Ohio, having its principal office and place of business at Amherst, Ohio, and a regular and established place of business at 5350 Mc-Dermott Drive, Berkeley, Illinois, within this district. (Amended Complaint para. Ill, and Amended Answer para. 3). 3. This action arises under the patent laws of the United States, 35 U.S.C. Sections 271, 281 et seq. (Amended Complaint para. I, and Amended Answer para. 1.) The following United States Letters Patent, all owned by plaintiff, are involved: Patent No. Inventor Date 3,048,498 J. W. Juvinall & J. C. Marsh August 7,1962 3.169.882 J. W. Juvinall, E. Kock & J. C. Marsh February 16,1965 3.169.883 J. W. Juvinall February 16,1965 Defendant is charged with directly infringing all the above patents and additionally with actively inducing and contributing to, infringement by others. (Amended Complaint paras. IV-XIV incl.) 4. Acts of defendant complained of by plaintiff as infringements with respect to each patent in suit, including actively inducing infringement and contributing to infringement, have been committed in this district and elsewhere subsequent to the issue date of each patent in suit. 5. The original complaint herein filed on July 16, 1965 named as defendants Nordson Midwestern, Inc. and Marvel Metal Products Co., alleged infringement of United States Letters Patent Nos. 3,048,498, 3,169,882, and 3,169,883 and prayed for injunctive relief and for damages together with costs. The original complaint was dismissed against defendant Marvel Metal Products Co. after it took a license under the patents in suit. Nordson Midwestern, Inc., the original defendant was a sales affiliate of the present defendant, Nordson Corporation. By stipulation between the parties, approved December 21, 1966, Nordson Corporation was substituted for, and in all respects stands in the place of, Nordson Midwestern, Inc. as party defendant. 6. On October 28, 1967, plaintiff, with leave of court, filed an amended complaint naming as defendant Nordson Corporation and alleging infringement of United States Letters Patents Nos. 3,048,498, 3,169,882 and 3,169,883 and praying for injunctive relief and for damages together with costs. Defendant answered the amended complaint on December 5, 1967 denying validity and infringement and asserted that the patents are not enforceable under theories of laches, fraud in the procurement of the patents, and patent misuse. Defendant also filed a counter-claim seeking a declaratory judgment of invalidity and non-infringement and non-enforceability of the patents asserted by the plaintiff. 7. The trial of the case began January 2, 1968, continued for sixteen days, and concluded January 23, 1968. At the beginning of the trial demonstrations were conducted which included the spray coating of articles by prior art methods and apparatus, by commercial methods and apparatus (Tr. 132-160). Both methods and apparatus of plaintiff embodying the inventions of the patents in suit and accused methods and apparatus of the defendant which are being currently marketed and are charged to be infringed, were demonstrated (Tr. 161-186). Both plaintiff and defendant conducted exhaustive pretrial discovery. At the trial plaintiff had three live witnesses (Tr. 189, 2542 and 2742) and relied on the testimony of nineteen deposition witnesses (2617, 3202-3257), and defendant had six live witnesses (1078, 1099, 1115, 1238, 1808 and 2446) and relied on the testimony of ten deposition witnesses (Tr. 1032, 1133, 1204, 1265, 1475, 1493, 1524, 1636, 1754, 2337 and 2422). BACKGROUND OF THE INVENTIONS Nonelectr astatic Spray Guns 8. Prior to 1944, substantially all industrial spray painting was accomplished by non-electrostatic air-spray guns where a small stream of paint forced through an orifice was hit by one or more high-velocity jets of compressed air which both atomized the paint and directed the atomized particles toward the work (article to be painted) (Tr. 200). 9. The principal type of non-eleetrostatie air-spray gun used prior to 1944 was a metallic gun held in the hand and manipulated by a workman to coat an article. Such a gun is commonly referred to as a “hand gun”. Guns were also marketed that were mechanically supported in spaced relation to a convey- or so that articles carried by the conveyor would move past the gun and be painted by the spray emanating from it. Such guns were referred to as “automatic guns”. (Tr. 200.) 10. Spray painting with such air-spray guns provided a high quality finish and permitted a reduction in labor costs over conventional hand painting techniques such as with the use of a brush, but spray painting was extremely wasteful of paint. Much of the paint sprayed, rather than being deposited on the work, was carried past the work and lost as “overspray”. The term “overspray” describes that portion of the paint sprayed which is not deposited on the surface of the work. Overspray represents a serious waste of paint, is a health hazard, and usually requires the use of relatively expensive overspray collecting equipment to prevent contamination of the factory area. In spraying certain articles with these air-spray guns, as much as 75% of the paint is lost as overspray. (Tr. 133-145.) Early Development of Electrostatic Spray Painting 11. The large waste of coating material associated with air-spray guns and resulting from “overspray” encouraged the search for spray painting systems which would deposit a greater percentage of the total paint sprayed on the article (the percentage of sprayed paint which is deposited on an article is called “transfer efficiency”). Those working in the art of spray coating concluded that if the particles of paint could be attracted to the article rather than being projected toward or in the direction of the article, the amount of overspray would be substantially reduced. Thus it was determined that the electrostatic attraction phenomena might be advantageously employed in spray painting. By imparting an electrical charge to the spray particles, these particles would be electrostatically attracted to the grounded article to be painted. At least some of the particles that would otherwise be lost in overspray would be deposited on the article and the transfer efficiency of the overall system would be enhanced (Tr. 202-203). Plaintiff Ransburg 12. The first commercial electrostatic spray painting system was pioneered by Harper J. Ransburg Company, a partnership, and plaintiff’s predecessor in the electrostatic spray painting business. The partnership, consisting of Harper J. Ransburg and his three sons, was engaged in the production and sale of kitchen cannisters and other housewares which were spray painted by conventional air-spray guns. Concerned over the large waste of paint in the use of conventional non-electrostatie air spray painting equipment, Harold Ransburg, one of the sons, turned his attention to the reduction of that waste. The outcome of his inventive efforts was the first commercially successfully, automatic electrostatic spray coating process, which is known as the “Ransburg No. 1 Process”. (Tr. 140-148, 190-204.) 13. The No. 1 Process, which was introduced commercially in the mid 1940s, employed compressed-air spray guns for spraying paint into an electrostatic field maintained between conveyorized articles and an electrode, comprising an open-ended, fire-wire, cage-like grid structure. Entering the field, the paint particles were electrically charged by bombardment with ions emanating from electrode wires and were urged toward deposition by the effect of the field (Tr. 194-197). The effect of electrostatic forces in reducing over-spray loss is manifest not only in actual paint savings, but also by the presence of deposited paint on article surfaces which do not face the gun. This characteristic of electrostatic spray painting is called “Wrap around”. (PX 484A, 487; RA 248-251, inch; Tr. 156-157.) The No. 1 Process substantially reduced paint losses as compared with the conventional, non-eleetrostatic air spray system. However, there were still significant paint losses, especially in painting open articles such as tubular metal chair frames and automobile steering wheels (Tr. 145). 14. Ransburg’s continued efforts in the electrostatic painting field culminated in another invention, namely the “No. 2 Process”. This process entirely eliminated the paint-wasting air blast and, in many applications, almost 100 percent transfer efficiency was attained (Tr. 207-208). One commercial form of the No. 2 Process was an automatic system utilizing a rotating, electrically charged paint atomizer or “head” of bell-like form on the inner surface of which the paint was distributed as a film. An electrostatic field was established between the atomizer and the work. Such field atomized the paint at the bell edge, highly charged the paint and deposited it on the work. (Tr. 207-210.) 15. Both the No. 1 Process and the No. 2 Process found extensive use in industry, but each had certain limitations (Tr. 247). The No. 1 Process still wasted much paint in the coating of some types of articles (Tr. 145). The No. 2 Process was not adapted for the use of some paints (Tr. 224), and it did not provide adequate coating in deep recesses (Tr. 157, 212). The high voltages, up to 100,000 volts, used in both systems created a hazard both with respect to operating personnel and with respect to possible fire or explosion. Commercial spray painting often involves the use of highly volatile solvents whose vapors may be flammable in air. Sparks from electrostatic painting apparatus may release enough energy to ignite paint or paint vapor. The achievement of safety thus became one of the goals in the further development of electrostatic painting. (Tr. 158-161, 245-246.) Other Major Companies 16. Starting in the 1940’s, after introduction of the Ransburg No. 1 Process, several of the country’s largest technically oriented companies pursued research and development in the electrostatic painting art. Ford Motor Co., General Motors Corporation, General Electric Company, and the DeVilbissi Co. were some of the companies that were seeking answers to the perplexing problems in this art. (PX 559, 560, 563, 566, 567, 571; Tr. 1032-77, 1265-1492.) Help from professional research organizations was also sought. (PX 567, Burnside, pp. 31-36, 44-45, 48-53, 63-69, 71-75; PX 571, Slatkin, pp. 41-45; PX’s 262-265, 267, 268, 270-278, 280, 283, 286, 288-295, 297, 298, 305 and 306; PX 564, Simpkins, p. 13; PX 565, Otto, p. 32.) Ford Motor Company 17. Because the proper painting of automobile parts is of great importance, the largest automobile manufacturers were among the first to develop an interest in electrostatic painting equipment (PX’s 559, 560, 566, 567, 571; Tr. 1493-1518). The early efforts of Ford Motor Company in this regard were directed toward an electrostatic atomization system simulating the Ransburg No. 2 Process and utilizing charged, rotating cup-like atomizing heads. Ford also experimented with an electrostatic painting system utilizing an atomizer in which paint was forced through an orifice under very high pressure. This type of pressure atomization is normally referred to as hydraulic or hydrostatic atomization. In order to charge the paint, Ford’s engineers employed a plurality of charged electrodes. (PX 566, Stueckle, pp. 8-9, 11, 15-16; PX 567, Burnside, pp. 18-21; PX 571, Slatkin, pp. 13-24, 33-34, PX’s 235, 244 and 255; DX 193.) 18. One form of hydrostatic spray device sought to be patented by Ford is shown in Australian Patent 211,044 (DX 179). In the illustrated device, it was intended that the paint be forced through a nozzle orifice and atomized under the influence of hydrostatic pressure. A plurality of charging electrodes are shown for effecting electrostatically charging of the atomized paint. A device of this general type, including twenty-eight charging electrodes surrounding the orifice, was experimented with at Ford in approximately 1955 (PX 235, 244 and 255); however, it was never used commercially. (PX 566, Stueckle, pp. 9, 11, 12, 20, 22, 23; PX 567, Burnside, pp. 88-89.) After several years of its own development efforts in electrostatic spray painting, Ford engaged the Engineering Research Institute of the University of Michigan to assist in the development of a high pressure paint atomizing system for industrial finishing (PX 262, 263; PX 571, Slatkin, p. 43). In spite of several years of work by Ford and the University of Michigan from 1955 through 1958, this effort to develop a finishing system was finally abandoned. (PX 306, 308; PX 567, Burnside, pp. 84-89.) Ford’s efforts to produce an acceptable hydrostatic electrostatic spray painting device in the middle 1950’s and its failure to do so despite its rather intensive development efforts are particularly significant. At or about the time that Ford initiated its work on a hydrostatic-electrostatic system, it was cognizant of its potential liability to Ransburg as a result of its use of a simulation of the Ransburg No. 2 Process. Accordingly, the corporate policy at Ford was to pursue a development effort which would yield an electrostatic spray coating system that would not be charged to be an infringement of the Ransburg No. 2 Process patents not here at issue (PX 281A, B and C). When the efforts with respect to a hydrostatic-electrostatic system did not yield a commercial system, Ford went forward with its simulated No. 2 Process approach and was ultimately found to have infringed the Ransburg No. 2 Process patents. (Tr. 2789; Ransburg Electro-Coating Corp. v. Ford Motor Company, D.C., 245 F.Supp. 308.), Ford is now a Ransburg licensee under these patents (Tr. 2789). General Motors Corporation 19. General Motors was also actively interested in electrostatic spray painting. Prior to 1947 it was licensed by Ransburg to use the No. 1 Process. (PX 559, Lamm, p. 5.) Prior to 1950 technical personnel from the Ternstedt Division of General Motors and from General Motors Research began to develop a spray coating system that would be as free of fire hazards and as efficient as possible (PX 559, Lamm, p. 5). General Motors technical personnel involved in brainstorming this development included Dr. Edward Martin of the Research Laboratory, Cleve Nixon, Director of Process Development for Ternstedt, Dr. C. Durward Tuttle, and Mr. Larson of the Ternstedt Division and Mr; Lewis J. Lamm (PX 559, Lamm, pp. 6-8). As a part of this effort in 1949 General Motors filed a patent application on an electrostatic painting system in which a diesel fuel nozzle was used to atomize the paint (DX 230, PX 312). The paint charging mechanism comprised a plurality of charged, pointed electrodes arranged somewhat like the spokes of a hubless wheel. Paint was projected from the grounded nozzle through the hub area toward the article and thus past the inner extremities of the pointed electrodes (PX 559, pp. 7, 19 and 20; PX 312). This apparatus was never used for painting in any General Motors plant (PX 559, pp. 12 and 19). The result of this work was the so-called Ternspray device. This device consisted of a charging mechanism including a plurality of pointed electrodes positioned well in front of and to one side of a conventional grounded air spray gun. The electrodes were directed toward a grounded plate and transversely of the spray projected from the gun (PX 559, Lamm, p. 5; PX 310). The Ternspray apparatus was used at General Motors (PX 559, Lamm, p. 10) in spite of the fact that paint had to be periodically cleaned from the changing needles to avoid the detrimental effects of blobs of paint detearing off the end of the needles onto the article being painted (PX 559, Lamm, pp. 16 and 17; PX 315, p. 58). Beginning in 1949 the Process Development Section of General Motors Research Laboratory started a project to improve the Ternstedt spray process and to adapt it to all possible painting activities at General Motors (PX 560, Gardner, p. 6). During this project, attempts were made to substitute a non-pneumatic, hydraulic atomizing device for the air spray gun (PX 560, Gardner, pp. 9, 13; PX 314). Emphasis upon development by the Process Development Section, however, was given the Tern-spray device and electrostatic atomizers rather than the non-pneumatic high pressure electrostatic process because at that stage both processes were acceptable and satisfactory in production while the non-pneumatic process was not satisfactory (PX 560, Gardner, pp. 22 and 23). As late as 1961 General Motors was still experimenting with high pressure non-pneumatic atomizing nozzles in electrostatic painting systems (PX 559, Lamm, pp. 11-13; PX 311). In spite of its efforts General Motors failed to develop a truly efficient electrostatic spray painting system using mechanical atomization and free of the deleterious effects of paint collecting upon the array of pointed charging electrodes. The DeVilbiss Company 20. In th late 1930’s, during the developmental stage of the No. 1 Process, Harold Ransburg gave a demonstration of electrostatic painting to the DeVilbiss Company of Toledo, Ohio, a leading manufacturer of non-electrostatic spray painting equipment (PX 563, Peeps, p. 5; Tr. 1070-1072). Thereafter, DeVilbiss supplied Ransburg with conventional air-spray apparatus for use in Ransburg’s electrostatic systems (Tr. 1073-1074). 21. Later, in 1941 and 1942, DeVilbiss and Slayter Electronics Corporation (later a division of Owens-Corning Fiberglas) undertook a joint effort directed toward the development of electrostatic, air-atomizing spray coating equipment (PX 563, Peeps, pp. 5-17; PX 564, Simpkins, pp. 10-27; PX 565, Otto, pp. 10-12). Initially, that effort involved experiments with an electrically charged, all metal, air atomizing spray gun disclosed by Bennett and Taylor in their U.S. Patent 2,491,889 (DX 141; PX 395) and their abandoned patent application Serial No. 427,638 (DX 142; PX 396; PX’s 317, p. 1, 321, PX 565, Otto, p. 10). These experiments proved the so-called “Bennett” gun unsatisfactory for spray painting (PX 563, Peeps, p. 16; PX 565, Otto, pp. 25, 27). Modified guns, which were intended to improve the charging characteristics by employing supplementary charging electrodes, were built and tested (PX 563, Peeps, pp. 16, 24; PX 565, Otto, pp. 17, 25-28). The modified gups also proved unsatisfactory (PX 563, Peeps, pp. 25-29; PX 565, Otto, pp. 30-32). 22. Although the Slayter (Owens-Corning) group abandoned its efforts, DeVilbiss continued (PX 563, Peeps, 29). After independently pursuing this matter, DeVilbiss entered into a joint development effort with the General Electric Company in early 1944 (PX 563, Peeps, 30). This joint effort with General Electric continued for some six years (PX 563, Peeps, 30-59). DeVilbiss’ efforts with Slayter and General Electric resulted in a spraying apparatus of the type shown in Patent 2,625,590 (PX 215, PX 364; PX 563, Peeps, 29). This patent was issued to D. J. Peeps, the DeVilbiss engineering executive principally responsible for its electrostatic spray painting activities. 23. DeVilbiss renewed its activity in electrostatic painting in the early part of 1960 by marketing electrostatic painting apparatus of Japanese origin (PX 563, Peeps 59-60). DeVilbiss stopped marketing this equipment in 1963 or 1964 (Tr. 1075, 1076). About this time, DeVilbiss hired several former research and development employees of Ransburg, including the inventors named in the patents in suit. It was only thereafter, and some 25 years after its initial exposure to Ransburg’s electrostatic painting systems, that DeVilbiss produced and marketed electrostatic spray painting equipment of its own design (PX 563, Peeps, pp. 73-74, 78; Tr. 1077). 24. Mr. Peeps, although a prolific inventor and the holder of some 40 patents, was unable to produce for DeVilbiss, a commercially acceptable electrostatic spray painting system in spite of assistance from General Electric (PX 563, Peeps, p. 59; Tr. 1077). EARLY DEVELOPMENT OF HAND HELD EQUIPMENT 25. Before the inventions of the patents in suit, all commercial electrostatic spray painting installations were “automatic” systems in which articles to be painted were moved in a conveyor past mechanically supported electrostatic spray charging devices (Tr. 158, 202-204, 211-216, 318-319). Since the electrostatic automatic systems did not require close attendance of operating personnel and the electrostatic equipment could be shut off manually or automatically if an operator need to approach the apparatus, the existence of a shock hazard was normally not of great concern (Tr. 158-159). Nevertheless there was a safety hazard in that an article on the conveyor might, as a result of swinging or improper positioning, approach the electrode so closely as to cause a dangerous spark (Tr. 159-160). An acceptable degree of safety was achieved with automatic systems by designing commercial installations so that the distance between the high voltage electrode and the articles to be coated was much greater than the distance at which the sparking would occur (Tr. 245-247) and by providing a switching device which turned off the voltage in the event of a spark (PX 574, tab 12). Installations were often caged in order to put the spray area “off-limits” (DX 206). 26. Several factors made the achievement of safety considerably more difficult with hand guns. One factor was the necessity of making a hand gun readily manipulable. Another was the wide variations in spacing between the charged gun and the grounded article being coated that necessarily occurred when using a hand gun (Tr. 292-295). A third factor was the greatly increased possibility of injury to an operator from inadvertently touching the portion of the hand gun at high voltage. Both of the latter two factors greatly increased the likelihood of sparks in the presence of flammable vapors. (Tr. 245-247; PX 138). 27. Early attempts to make a safe electrostatic painting system using a hand spray gun took several forms, none of which ever became commercial (Tr. 318, 319). In some forms sparks and shocks were to be prevented by mechanically limiting the ability of a man to approach a high voltage electrode or limiting the ability of a high voltage electrode to approach an article or other grounded object (Tr. 2639-2641). One of the earliest proposals for a safe hand gun system employed mechanical restraints on the operator and on the gun, and is illustrated in Harold Ransburg’s Patent 2,546,701 filed in 1944. This mechanism was never used because it proved incapable of preventing sparks under all conditions and manipulation of the gun was too restricted. (PX 423; Tr. 319-321.) Other early forms of hand gun systems attempted to prevent sparks by using an electronic circuit which would act in response to electrical changes occurring within the system immediately prior to a spark to turn off the voltage source before a spark could occur (PX 574, tab 12). These expedients all proved to be impractical in hand gun systems. While they could turn off or reduce the supply of the electrical energy to the portion of the gun at high voltage, they could not prevent the instantaneous and dangerous discharge of the energy stored on the high voltage portion during normal operation. (PX 138, col. 5, lines 10-14.) THE INVENTIONS OF THE PATENTS IN SUIT Patent No. 8,048,498 28. Patent 3,048,498 (PX 138) is directed toward a method and apparatus for efficiently and safely depositing paint that is atomized either mechanically or electrostatically. The patent discloses the incorporation of the invention into hand-held and automatic painting systems. The patent further discloses that the intensity of the electrical discharge ultimately obtained from a paint charging electrode in such a system is determined by the electrode size, the electrical conductivity of the electrode material and the electrode shape (particularly as to “sharpness” or “bluntness”). The patent defines these electrode characteristics collectively by the phrase “effective capacity”. (Tr. 325-328; PX 138, col. 4, lines 50-75 and col. 5, 1. 1-2.) The patent discloses that the danger of fire or explosion in an electrostatic painting operation varies with the type of paint being used, the paint solvent, and the temperature. The patent teaches how a paint charging electrode with an effective capacity of the proper value, a high resistance having the proper location and value, and a high voltage source with the proper output voltage characteristics can be combined to electrostatically paint safely under differing operating conditions. Such a combination makes possible variations of eleetrode-to-article spacing while maintaining the potential gradient of the electrostatic field at values consistent with high transfer efficiencies but still below values at which objectionable sparking occurs. The claims of the patent define methods and apparatus for electrostatically spray painting safely for a variety of operating conditions. (Tr. 284-287, 291-298, 313-318, 325-332, 2291.) The ’498 patent teaches that the “effective capacity” of a paint charging electrode can be measured by comparing the energy of its electrical discharge to the energy of the electrical discharge of polished metal spheres of different diameters. The ’498 patent sets forth a test for measuring the “effective capacity” of an electrode in an electrostatic system by such a comparison. The claims of the ’498 patent that refer to the “effective capacity” of a charging electrode are definite since they define the value of “effective capacity” in terms of that of metal sphere of either one centimeter radius or three centimeters radius. One skilled in the art of electrostatic spray painting, by using the teaching of the ’498 patent, can readily determine the “effective capacity” of a charging electrode of a given electrostatic painting system and can determine if the painting system falls within the claims of the ’498 patent. The invention of the ’498 patent was completed by October, 1954. (DX 7-1; DX 139, pp. 86-87; DX 140; Tr. 2623-2641.) The invention of the ’498 patent was incorporated by Ransburg into its commercial devices known as the No. 2 Process hand gun, the R-E-A (air atomizing) and the R-E-H (hydrostatic atomizing) electrostatic guns. (Tr. 2733-2737.) Patent No. 3,169,882 29. Patent 3,169,882 (PX 139) is directed toward improving transfer efficiency by increasing the charge impressed on the particles of mechanically atomized paint as by compressed air or hydrostatic pressure, and it is capable of projecting paint into recesses and atomizing a wider range of paints than can be handled in the No. 2 Process. The specific embodiments shown in the drawings of the ’882 patent are air atomizing electrostatic spray guns. The gun of the ’882 patent carries at its front end a small elongated, wire-like, spray-charging electrode. Undesirable electrical shielding of the tip of the electrode is eliminated, by making at least the forward portion of the gun entirely of insulating material except for the electrode, thereby enhancing the filed concentration and ion production at the tip to produce at that location an extremely high potential gradient and a concentrated zone of ions. The paint spray particles are atomized and directed in such a way that they become highly charged by ion bombardment while passing through the concentrated zone of ions before the spray has expanded appreciably. Spray guns using this invention provided a highly effective way of charging paint particles which had been mechanically atomized (as by compressed air or hydrostatic pressure) and attained high transfer efficencies. The invention of the ’882 patent was completed by October, 1957 (DX 8, Tr. 1790-1795). The invention described and claimed in the ’882 patent is incorporated in both Ransburg’s R-E-A and R-E-H guns. Patent No. 3,169,883 30. Patent 3,169,883 (PX 140) is derected toward hydrostatic-electrostatic spray coating methods and apparatus. The inventions of this patent comtemplate the projection of paint from a highly charged nozzle in the form of a thin expanding film having a length (as measured from the nozzle orifice to the front edge of the film from which atomization takes place) of only a fraction of an inch. The paint so projected is both finely atomized and highly charged and forms a pattern eminently adapted for high speed production painting. A further aspect of the inventions of the ’883 patent is the addition of an elongated wire-like electrode which is selectively oriented relative to the thin expanding film emitting from the nozzle orifice so as to further enhance the transfer efficiency of the overall system. This electrode extends forwardly from the nozzle and is maintained closely adjacent to but spaced slightly from the liquid film and terminates adjacent the forward edge of the film. The increase in transfer efficiency that accompanied the inclusion of the projecting electrode in a hydrostatic-electrostatic system results from the concentration of the field at the optimum location in the proximity to particles being atomized from the film edge. The invention of the basic hydrostatic-electrostatic system and method was completed by January 1953 (Tr. 2563-2579). After this high pressure electrostatic device had proven satisfactory, further development efforts were pursued which culminated in the invention defined in claims 5, 6, 7, 9, 12, 14 and 15 which was completed approximately December, 1957 (DX 107, p. 93; Tr. 1332-1340). THE PLAINTIFF’S COMMERCIAL EMBODIMENTS OF THE INVENTIONS The Ransburg No. 2 Process Hand Gun 31. The first commercial form of an electrostatic hand gun was Ransburg’s No. 2 Process hand gun. This gun embodied the invention of the ’498 patent. Marketing of this gun began in 1958. The atomizing bell of the No. 2 Process hand gun is made of insulating material and a resistive coating on its outside surface is a charging electrode of low effective capacity. This charging electrode is connected to a high voltage source through a closely adjacent resistor and a flexible cable. This connection is made within a barrel member made of nonconducting material. Paint is supplied to the inside surface of the bell and formed into a thin film at its edge by rotation of the bell. The electrostatic field between the charging electrode and the article being coated atomizes the paint into a charged spray. The charging electrode is sufficiently resistive to prevent an instantaneous discharge of all the energy from the electrode. The resistor is placed at the front of the barrel member adjacent to the charging electrode and a small wire is used to contact the charging electrode on the rotating bell to limit the amount of electrical energy stored on the connector between the electrode and the resistor. The No. 2 Process hand gun deposits almost 100%. of the paint, is freely movable, and at the same time provides adequate safeguards against objectionable shocks to personnel and against sparks intense enough to cause fires or explosions. (Tr. 161-166, Tr. 2747; PX 536.) The Ransburg R-E-A Gun 32. The Ransburg R-E-A gun, an air atomizing electrostatic gun, which embodies the inventions of the ’498 patent and the ’882 patent, was first marketed in 1962 (PX 536). The R-E-A gun includes a paint atomizer formed of nonconduetive material and a paint charging electrode of low effective capacity in the form of a thin wire carried by the atomizer. The charging electrode is connected to a high voltage source through a resistor located within a barrel member of insulating material. Paint is ejected from a small orifice in the atomizer at the front end of the barrel member of insulating material. Jets of compressed air form the paint into a spray, direct substantially all of it through a highly ionized zone formed by the end of the thin wire electrode, and shape the spray into an elongated pattern. The spray particles are highly charged by ion bombardment in passing through the highly ionized zone. An advantage of the R-E-A gun over the No. 2 Process hand gun is that the R-E-A gun can project the paint into recessed portions of an article. (Tr. 170-176, 526-536, 2736-2737; PX’s 414, 534.) The Ransburg R-E-H Gun 33. The R-E-H gun embodies the inventions of the ’498, ’882 and ’883 patents in suit. Paint is supplied to the R-E-H gun under high hydrostatic or hydraulic pressure, and is projected through a noz- zle with a very small opening which is constructed to form the paint into a thin expanding film with straight sides and having a length — between the nozzle orifice and the front edge of the film — of only a fraction of an inch. The paint is finely atomized from the front film edge by interaction with air. The gun incorporates a thin elongated electrode positioned adjacent the nozzle orifice and in a plane parallel to, but spaced from, the paint film and its front top portion terminates in proximity to the atomizing zone. The electrode is connected to a high voltage source through a multimegohm resistor. When the electrode is energized by the high voltage source and the gun is adjacent an article to be coated, an electrostatic field is established between the electrode and the article being coated. The portion of the field adjacent the front tip of the electrode has a high intensity gradient and it highly charges the atomized paint and deposits it on the article. Except for the electrode and the atomizing nozzle the gun is substantially entirely of insulating material, and the resistor immediately adjacent the electrode is encased in an insulating barrel of the gun. Because of the use of high pressure as a means for effecting atomization the amount of blow-by and bounce-back of atomized paint particles that occurs is reduced over that indicated in the operation of the R-E-A gun; however, the R-E-H gun is not as efficient as the Ransburg No. 2 Process gun. The R-E-H gun was first publicly displayed in 1962 and was introduced to the market in 1963. (Tr. 177-182; PX 533, Tr. 2734-2736; PX 558, Daly. p. 9; Tr. 2762, PX 536.) EVOLUTION OF DEFENDANT NORDSON’S INFRINGING DEVICES Westinghouse-Nordson Activities 34. E. H. Griffiths, Jr., a graduate engineer was employed by the Westinghouse Headquarters Manufacturing Laboratory. This organization functioned to develop new equipment that would benefit the operating divisions of Westinghouse Electric Company. In mid 1955 Griffiths was placed in charge of investigating electrostatic painting for possible use by Westinghouse. (PX 557, Griffiths, pp. 13, 17, 18, 22.) Impressed by Ransburg’s demonstration of its No. 2 Process hand gun in which the spray man touched the charging electrode, Griffiths initiated work on a similar hand gun in 1959. Shortly after its start the objective of this project was changed to the development of an electrostatic hydrostatic hand gun. (Tr. 3211-3220.) This project continued at Westinghouse from 1959 through 1961. Henry E. Lehman, a graduate engineer employed by Westinghouse in June, 1959, also worked with Griffiths in trying to make the experimental gun safe. The first proposed Westinghouse electrostatic hydrostatic hand gun did not include a resistor adjacent the atomizing nozzle. (PX 562, Lehman, pp. 4-6.) Westinghouse first tried to develop a special voltage supply in an effort to reduce the energy available at the front of the gun. The special voltage supply was to. be used with the electrostatic hand gun being developed by Westinghouse and with the automatic painting installations of Westinghouse. (PX 562, Lehman, pp. 8, 9.) After discovering that such special voltage supplied would not answer its needs, Westinghouse began experimenting with resistors in the end of its high voltage cable adjacent the charging electrode. (PX 562, Lehman, p. 32.) In late 1960 after further work, it was discovered that resistance alone was not the answer and Lehman acquired and inspected a Ransburg No. 2 Process hand gun at the Westinghouse Laboratories. (PX 43-2; PX 562, Lehman, pp. 44-45, 52-54.) Westinghouse next tried to prevent corona from the front of the gun by shrouding the spray nozzle with a conductive member having rounded smooth surfaces. Westinghouse subsequently abandoned the use of shrouds and used insulating materials for the nozzle’s construction to reduce the intensity of the electrical discharge at the front end of the gun. (PX 30; PX 31; PX 562, Lehman, pp. 47, 52-54, 69.) 35. Nordson Corporation supplied parts for prototypes of the Westinghouse electrostatic hydrostatic gun beginning in 1959 including handles and non-conductive barrel members. Samuel Rosen, Nordson’s Chief Engineer, participated in the design of prototypes of the Westinghouse gun. Eric Nord kept himself informed of the development of the Westinghouse gun during the period from September 1959 until February 1962 (PX-484A RA 89, 95, 99). 36. Westinghouse Electric Company filed two patent applications upon its electrostatic-hydrostatic spray gun on March 8, 1962. One of these applications issued as a patent on April 19, 1966 to H. E. Lehman and E. H. Griffiths, Jr. This is U.S. Patent No. 3,246,844, entitled Electrostatic Painting Apparatus for Explosive Atmosphere. The other of these applications, Serial No. 178,478, was filed in the name of E. H. Griffiths, Jr., as sole inventor. This other application was abandoned and was succeeded by a continuation application, Serial No. 554,247, which was still pending in the U.S. Patent Office at the time of the trial. This latter application names H. E. Lehman and E. H. Griffiths, Jr., as joint inventors (PX 484A, RA 57, 58, 59.) 37. In September of 1961 Eric Nord, President of Nordson, confirmed the interest of Nordson in discussing a license to make, use and sell the Westinghouse hydrostatic electrostatic spray gun (PX 183). In October 1961, Kenneth H. Daly, Vice President of Nordson, informed Nordson’s distributors and sales managers of the possibility that Nordson would have an airless electrostatic hand gun available for sale in two or three months (PX 484A, RA 82). In December of 1961 Daly contacted T. L. Bowes, General Patent Counsel for Westinghouse, as agent for Eric Nord in an attempt to obtain an exclusive license under the Westinghouse patent relating to the airless electrostatic hand gun. Eric Nord was interested in the protection it would afford to Nordson in making and selling this electrostatic equipment. (PX 484A, RA 84; PX 484C, RA 264; Tr. 3239-3241.) Westinghouse refused to grant an exclusive license to Nordson but offered them a non-exclusive license. The non-exclusive license was accepted by Nordson. (PX 186-1, PX 186-2.) Nordson has been licensed by Westinghouse since February 26, 1962 to use the inventions of U.S. Patent 3,246,844, abandoned Patent Application Serial No. 178,478 and its continuation application Serial No. 554,247 (PX 484A, RA 55-60). Nordson Corporation has paid Westinghouse in excess of $20,000 in royalties under this license agreement (PX 484A, RA 61). Defendant's Model A Gun 38. Nordson’s first commercial efforts under the license agreement involved the sale of a gun such as that shown in PX 27, the so-called Westinghouse gun (PX 484C, RA 270 and 271). Eric Nord and Sam Rosen began designing a shorter gun that was designated the Model A gun (PX 484C, RA 269; PX 570, Nord, p. 99). Although the barrel of the Model A gun was shorter than the barrel of the Westinghouse gun, the Model A gun used the inventions of the Westinghouse patent applications and was structurally similar to the Westinghouse gun. Nordson Model A series of guns included a hand gun, the pre-Versa automatic gun and the Versa automatic gun. The Model A guns all had barrel members made of insulating material and utilized an electrically charged spray nozzle. These guns all had a resistance adjacent the nozzle at the front end of the gun. As with the Westinghouse gun, a multimegohm resistor was housed in a cartridge-cable assembly that was inserted into the barrel member and contacted a machine screw in providing the electrical connection to the spray nozzle. (PX 484A, RA 100, 107; PX 484C, RA 272-274; PX 570, Nord, pp. 96, 97; PX 27 and PX 89). A Model A Versa hand gun was first sold to a Nordson sales subsidiary in June, 1962 (PX 484C, RA 289.) 39. In the first Model A hand gun sold by Nordson, the conductance of the paint in the paint passageway electrically connected the spray nozzle with the machine screw that projected into the paint passageway and served as a charging terminal in the passageway. (PX 484A, RA 110A.) By February, 1963 springs were placed in the paint passageway to form the electrical connection between the spray nozzle and the charging terminal (PX 484, RA, 117), but this made the guns less safe than the earlier guns in which the conductance of the paint was used to form the connection (PX 484A, RA 110B and 111). Nordson then tested “nozzle adaptor assemblies” including a teflon-graphite conductive sleeve to provide the electrical connection in the passageway between the spray nozzle and the charging terminal (PX 484A, RA 119) . Model A guns were tested by determining the incendive or explosive characteristics of the guns with different values of resistance in the gun and the voltage supply, and with different teflon-graphite sleeves (PX 484A, RA 120) . Eric Nord participated in these tests (PX 484A, RA 121-123). Starting April, 1963 all Model A electrostatic guns (hand and automatic) were equipped with nozzle adapter assemblies having a conductive sleeve to provide safer operation (PX 484A, RA 124; PX 106). Nordson continued its development of a resistive type electrical connection between the spray nozzle and the charging terminal (PX 484A, RA 125). 40. John Carney, a graduate engineer, was employed by Nordson in April, 1963 and worked in research and development of Nordson’s products (PX 484A, RA 126 and 127). Part of Carney’s duties were evaluating the safety features of the Nordson electrostatic guns (PX 484A, RA 128). Carney ran explosion tests and experimented with changes in the gun design in an effort to minimize the chance of a spark from igniting an explosive mixture of solvent and air (PX 484A, RA 129). Sam Rosen, Chief Engineer of Nordson, and Wilfred Swanker, a professional engineer licensed by the State of Ohio, worked with Carney on these tests (PX 561, Carney, p. 23). 41. Prior to the execution of the Westinghouse-Nordson license agreement, Nordson Corporation received a report dated October 19, 1961 on the new Ransburg electrostatic-air (R-E-A) Model No. 301E hand gun including a sketch of the gun and the power supply (PX 484A, RA 206; PX 55). In December, 1962, Nordson borrowed an R-E-A gun manufactured by plaintiff for distribution by Binks Mfg. Co., from Pittsburgh Spray Equipment Co., in Pittsburgh (PX 484A, RA 207). Employees of Nordson examined and tested the R-E-A gun in December, 1962 (PX 484A, RA 208). Sam Rosen, Frank Ziroe, Eric Nord, Wilfred Swanker and John Carney were present (PX 486, PI 19b). The voltage on the projecting wire-like electrode at the front end of the R-E-A gun was measured (PX 484A, RA 211) and some of the features of operation of the gun were evaluated as compared with the Nordson Model A electrostatic gun (PX 484A, RA 212). The R-E-A gun was tested in the Nordson laboratory again on or about February 1, 1963 (PX 484A, RA 221; PX 100). Defendant’s Model B and BA Guns 42. In May, 1964 Nordson obtained a Ransburg electrostatic-hydrostatic (R-E-H) hand gun manufactured by plaintiff for distribution by Binks under the name Binks Model 49 (PX 484A, RA 138). While the Binks Model 49 electrostatic spray gun was in Nordson’s possession in May, 1964, the gun was X-rayed, photographed, partially disassembled, examined and tested and some of its component parts were measured to determine their dimensions (PX 484 A, RA 139). Negatives of the X-ray photographs were retained by Nordson (PX 114-1 and 114-2). On May 13, 1964 John Carney of Nordson measured the output voltage of the Binks Model 49 gun under no load conditions and with various load resistors connected between the projecting wire-like electrode and ground (PX 484 A, RA 140; PX 112-1). About May 15, 1964, Samuel Rosen, Chief Engineer of Nordson, made a drawing, approximately full scale size, of this gun labeled “Hand Ransburg Binks gun” which included notations of the materials from which component parts comprising the gun barrel were made (PX 484A, RA 142 and 144; PX 111). The drawing also included notations of the value of the resistors within the gun barrel and the diameter of all the wire members forward of the resistors within the barrel. Other detail drawings of the Ransburg equipment were made including a dimensioned drawing of the nozzle holder of the gun (PX 484A, RA 150; PX 112-7). Nordson also tested the Binks Ransburg electrostatic gun and made a wraparound test comparison of it with the Nordson gun (PX 484A, RA 135). Wraparound is one indication of the relative paint utilization efficiency of an electrostatic spray coating device (PX 484, RA 192) and was used by Nordson for that purpose (PX 570, Nord, pp. 168, 169). 43. Utilizing the information gained from its examination and testing of the R-E-H gun, Nordson produced an electrostatic-hydrostatic hand gun which was a detailed copy of the Ransburg R-E-H gun. This gun was designated as its Model B hand gun (PX 484A, RA 160; PX 109). The drawing from which this gun was made was prepared by Samuel Rosen and bears the date June 23, 1964. (Tr. 2967-2972; PX’s 109, 111, 547). This Model B gun included a projecting wire-like electrode having a diameter of .020 of an inch and positioned offset from the center line of the coating material orifice of the spray nozzle by 0.166 of an inch, exactly as included in the R-E-H gun (PX 484A, RA 162a, and RA 163a). No commercially available Nordson electrostatic spray coating equipment prior to the Nordson Model B hand gun included any form of wirelike electrode that projected forwardly from the front of the spray gun and Nordson Corporation has no drawings dated prior to June 23, 1964 illustrating such an electrode in its electrostatic spray guns (PX 484A, RA 136 and RA 137). The Nordson Model B hand gun also included two small wires, both having a diameter of less than .014 of an inch, to provide the electrical connection between the projecting wire electrode and the resistance element in the barrel of the gun, also as included in the R-E-H gun (PX 484A, RA 162e and RA 163i; PX 484C, RA 302 and 303). Nordson sold no guns prior to the Model B hand gun having such wire connectors and has no drawings dated prior to June 23, 1964 showing such wire connectors as a part of the design of its electrostatic spray guns (PX 484 A, RA 168e and RA 168i; PX 484C, RA 307e and RA 307i). Other features of the R-E-H gun present in the Model B gun and not present in earlier models of Nordson equipment or in earlier Nordson designs, are a removable member of insulating material carrying the valve seat and one of the contact wires and held to the forward end of the barrel member by a retaining nut of insulating material, and the high voltage cable entering the gun at the base of the handle rather than into a rigid cable-cartridge assembly that extended over the handle as in the Nordson Model A hand guns (PX 484A, RA 162d, RA 162f, RA 162g, and RA 162j, RA 163d, RA 163f, RA 163g and RA 163j, RA 168d, RA 168f, RA 168g; PX 484C, RA 304, RA 305, RA 307d, RA 307f and RA 307j). The Nordson Model B electrostatic hand gun was safer than the Nordson Model A electrostatic hand gun and exhibited better “wraparound” characteristics in the deposition of coating material than the Nordson Model A electrostatic hand gun (PX 570, E. T. Nord, 169). 44. Few Model B hand guns were sold (Tr. 748, 749). The Model B gun had no independent resistor element incorpo rated in the barrel adjacent the projecting wire-like electrode (PX 438, PX 98 4). Nordson modified its design to add a 75 megohm resistor between the termination of the high voltage cable and the electrically conductive parts at the front end of the gun. This revised hand gun, designated the Model BA gun, was the same construction as the Model B hand gun except for the addition of the resistor (PX 484A, RA 175). The Model BA hand gun was a closer copy of the Ransburg R-E-H hand gun (PX 111) and was safer than the Nordson Model B hand gun (PX 484A, RA 176). In its news release referring to either the Model B hand gun or the Model BA hand gun, Nordson stated, “A lightweight, easy-to-handle hand gun now makes it possible for painters to combine the convenience of hand spraying with the advantage of airless, electrostatic systems. * * * The technique offers spray efficiencies as high as 85%— with losses of finishing material to overspray and bounce-back running as low as 15%. * * *” (PX 146, pp. 10 and 11; PX 484C, RA 313). Defendant’s Model C and CA Guns 45. The electrostatic spray guns that Nordson was marketing at the time of trial were the Model C and Model CA guns (PX 121 and PX 122). These guns were first sold in early 1965 and 1966, respectively (PX 484C, RA 293 and RA 294; PX 160-5 and PX 160-6). The Model C gun retained the features of Ransburg’s inventions that had been incorporated in the earlier Nordson guns. The electrical components of the Nordson Model C hand gun and of the Nordson Model CA automatic gun forwardly of the metallic valve actuating components are substantially the same (PX 484A, RA 184). The Model C and CA guns are as efficient as the Model B electrostatic hand gun (PX 484A, RA 223). INFRINGEMENT 46. With respect to each of the three patents in suit defendant denied that each of the accused models of its electrostatic-hydrostatic guns was used in an electrostatic depositing device (PX 485, RA 1-54). However, transfer efficiency tests of the Nordson accused devices, both the hand gun as well as the automatic versions, show that they are electrostatic depositing devices. The transfer efficiency when voltage is applied to Nordson Model C and CA devices is from 22% to 65% greater than when the voltage is not applied to them. (PX’s 434A-E, inclusive; Tr. 444-464.) In defendant’s public representations about its Model A guns it admitted “Paint utilization is improved up to an additional 30 percent over straight heated airless” (PX 495; Tr. 2505) and about its Model C guns it stated that “from the addition, of an electrostatic power pack * * * material savings alone can amount to 50% * * * ” (PX 200, Nordson advertisement 306-1-073). 47. The accused devices of the defendant (including the Model A Pre-Versa automatic guns, Model A Versa automatic and hand guns Model BA hand gun, Model C hand gun, and Model CA automatic guns) are sold for use in systems including grounded supports for articles to be coated which may be grounded conveyors, a source of high voltage that creates an electrostatic field between the spray device and the article to be coated and a suitable coating material source connected to the spray devices (PX’s 200, ad 306-1-022; 430, 432 and 438). In most instances the accused devices are sold with a source of high voltage designed especially for use with the accused devices (PX 200, ad 306-7-032). Infringement of the ’498 Patent 48. By defendant’s responses to Requests for Admission, the issues of non-infringement were reduced. However, with respect to the ’498 patent defendant: (a) denied that each of its devices in a coating system were subject to variations in spacing between the charging electrode and the articles that could cause objectionable changes in potential gradient (PX 485, e. g., RA 8g); (b) denied that each of its apparatus had a charging electrode having an “effective capacity” less than that of a metal sphere having a radius of about one centimeter (PX 485, e. g., RA 1e); and (c) denied that its Models B, BA, C and CA and certain of its Model A guns included a resistance immediately adjacent the charging electrode (PX 485, e. g., RA 1c and RA 4c). 49. Contrary to the position taken by defendant, when used in electrostatic coating systems, defendant’s accused devices are subject to variation in spacing between the device and article being coated. Such variations could in a conventional electrostatic spray coating system cause an objectionable change in potential gradient of the electrostatic field between the spray device and the article, but when defendant’s accused devices are used in the system they do not cause an objectionable change in the potential gradient under such conditions. (Tr. 465-6; PX 432.) 50. Comparative tests conducted by plaintiff on (1) a Nordson Model C device, and (2) a metal sphere of 1 centimeter in radius connected in a circuit which included a cable resistance of 189 megohms, a gun resistance of 78 megohms, and a Nordson Model B-500 voltage pack operating at full voltage output having a resistance of 500 megohms, showed that the effective capacity of the discharge system of the Nordson device under test was less than that of the aforementioned metal sphere and when exposed to an atmosphere containing the most explosive mixture of hexane and air did not cause an explosion. These tests also showed that the magnitude of the resistance in the circuit was sufficient to minimize variations in the potential gradient of the field which would have occurred had not the resistance been present. These tests also showed that at all distances objectionable discharge of electrical energy of a character to initiate a fire or a shock to an operator was avoided. (Tr. 466, 467, 495-500; PX 435 A-C, inclusive.) 51. Each of the defendant’s devices includes a multimegohm resistor in the barrel to the device immediately adjacent the charging electrode of the device. The value of the resistance of such resistor is such that when the device is connected to a high voltage source in an electrostatic spray coating system the resistance in the device immediately adjacent the charging electrode is a substantial portion of the resistance of the circuit in which the device is connected (Tr. 496, 504, 505, 512; PX 428, 429, 470, 480-483). 52. The construction of the accused devices of defendant, or the use of such devices in an electrostatic spray painting system as well as such a system itself, or its use, find a complete response in one or more of the asserted claims of the ’498 patent. Each of the accused Model A devices (Pre-Versa automatic and Versa automatic and hand) or the systems incorporating such devices for spray painting respond fully and in every respect to claims 9, 12, 15, 17 and 19. In addition the accused Model A Versa hand gun or the system incorporating such hand gun for spray painting responds fully and in every respect to claims 4, 5 and 20. The accused Model BA hand gun or the system incorporating such hand gun for spray painting responds fully and in every respect to all the claims asserted. The accused Model C hand gun or the system incorporating such hand gun for spray painting responds fully and in every respect to all the claims asserted. The accused Model CA gun or the system incorporating such gun for spray painting responds fully and in every respect to Claims 8, 9, 10, 12, 13, 15 and 16 to 19 inclusive. (Tr. 768-773, PX 477.) Infringement of the ’882 Patent 53. By defendant’s responses to Requests for Admission, the issues of non-infringement were reduced. However, with respect to the ’882 patent, which was asserted against only the Nordson Model BA, C and CA electrostatic spray guns, defendant: (a) denied that in each of the accused guns there was a single ionized atmospheric zone through which the spray was projected (PX 485, e. g., RA 22f); (b) denied that in each of the accused guns there was an atomizing device composed substantially entirely of insulating materials (PX 485, e. g., RA 26a); (c) denied that liquid coating material was atomized into fine spray particles by interaction with air (PX 485, e. g., RA 26a); and (d) denied with respect to claim 3, that substantially all the lines of electrostatic force were concentrated at the electrode tip (PX 485, e. g., RA 26e). 54. To establish the presence of only a single highly ionized zone when the accused Nordson devices are in operation, photographs were taken of the accused Nordson Model CA gun connected in a system operated under representative conditions with high voltage applied to the charging electrode of the device. These photographs illustrate that a corona glow discharge was produced at the electrode tip but provide no evidence of corona glow discharge at the spray nozzle. This evidence establishes that defendant’s accused devices (Models BA, C and CA) when used in an electrostatic spray coating system, provide a single highly ionized zone through which the spray particles pass. (PX 442 A-C; Tr. 555-566). 55. Each of Nordson’s accused devices, Models BA, C and CA, is either composed substantially entirely of insulating material or its front portion is formed substantially entirely of insulating material (Tr. 549, 792; PX 485, RA 24a, 24b, 25a, 25b; PX 478). 56. Defendant’s accused devices when used in an electrostatic spray coating system atomizes coating material into fine spray particles by interaction with air (Tr. 724-726). 57. The construction of the accused devices of defendant and systems incorporating such accused devices for electrostatic spray painting find a complete response in one or more of the asserted claims of the ’882 patent. (Tr. 792; PX 478.) Infringement of the ’883 Patent 58. By defendant’s responses to Requests for Admission, the issues of non-infringement were reduced. However, with respect to the ’883 patent, defendant: (a) denied that each of its devices projected material from the orifice with “very high velocity” (PX 485, e. g., RA 15b); (b) denied that each of its devices projected coating material from the orifice as an expanding film of coating material having straight sides (PX 485, e. g., RA 15b); (c) denied that atomization was effected from the edge of the film (PX 485, e. g., RA 15c); (d) denied that its devices gave spray spot sizes no greater than .020 of an inch (PX 485, e. g., RA 15c); (e) denied that quiescent atmosphere was maintained during operation of electrostatic spray coating systems which employed the accused devices (PX 485, e. g., RA 15d); and (f) denied that relative movement between the orifice and the article surface was transverse to the general direction of spray particle movement during particle deposition (PX 485, e. g., RA 15h). 59. Defendant’s accused devices project coating material at a very high velocity, as admitted by defendant’s expert, Dr. Hines (Tr. 625, 670-675, 721-725, 2298-2299). 60. High speed motion pictures taken during the operation of defendant’s accused equipment under representative conditions (and single frames taken from the film), show that the spray nozzles of the accused devices produce a thin expanding film having straight sides which define an angle of at least 15°. (Tr. 668-669, 681-732; PX’s 451, 452, 459, 461-468 inclusive and 486, RI 6.) 61. High-speed motion picture sequences and high-speed photographs show that liquid coating material is projected from defendant’s accused