Harding, the junior party1 in an interference2 seeks reversal of the decision by the Board of Patent Interferences which awarded priority of invention to the senior party, Steingiser et al.3
The nature of the invention in issue is suggested by the single count, which reads:
“2. Stabilized polyethylene composition comprising a normally solid polymer of ethylene and a stabilizing amount below 0.5 percent of *7494,4'thiobis (6 ierf-butyl-meta-eresol).”
Both parties have discovered that polyethylene compositions may be stabilized by addition of small amounts of 4,4'thiobis (6 ieri-butyl-meta-cresol) hereinafter referred to by its trade name, Santowhite Crystals. They indicate in their applications that the ■claimed composition has superior stability as to electrical properties.
Steingiser stands on his filing ■date. Harding, as the junior party, has the burden of proving priority by a preponderance of the evidence. The board concluded, and we agree, that the basic issue is whether Harding can establish prior reduction to practice.
The evidence on behalf of Harding describes an experimental project,, said in his brief to have been “directed to finding an anti-oxidant for polyethylene electrical insulating material which exhibited better resistance to discoloring than those in use.” In that project polyethylene compositions using various antioxidants were subjected to hot milling to accelerate oxidative degradation of the resin in order to determine the efficacy of the antioxidants; using power factor, dielectric constant and reflectance tests as criteria for determining the effect of the degradation caused by the hot milling.
The board made certain findings of fact, which appellant does not challenge, and which we find supported by the record. Harding, assisted by one Hyer, began a series of experiments in the latter part of 1952 to find an effective stabilizer or antioxidant for polyethylene to be used as electric insulating material which would exhibit better resistance to discoloration than stabilizers then in use. Among the antioxidants tested was Santowhite Crystals, the compound called for by the count. Hyer actually prepared the compositions, which after being hot milled, were pressed into plaques. The plaques were then submitted to the Physical Testing Laboratory (operated by the assignee of the Harding application) for power factor, dielectric constant and reflectance tests. Harding, upon receipt of the results reported to him by the laboratory, copied them into his notebook or weekly reports. As a result of Harding’s work, which had been done at the request of a group of research personnel, designated the Electrical Insulating Group, Santowhite Crystals were “recommended for further trial.” Griesser, who serves as a corroborating witness, was then assigned to repeat and carry forward Harding’s work.
Appellant relies on Griesser’s work for establishment of Harding’s alleged reduction to practice. Griesser’s activities commenced in March 1953 and terminated near the end of the following month. During that period he prepared three batches of polyethylene for testing; one control containing no antioxidant and two containing 0.1% and 0.2% Santowhite Crystals respectively. Each batch was milled at 160° for two hours, with samples taken therefrom after five minutes and two hours respectively. Those samples, after being pressed into plaques, were sent with a standard request form to the Physical Testing Laboratory. The test results obtained by the laboratory were recorded in duplicate on a standard form, a copy being retained in the files of the laboratory, and the original returned to Griesser. Due to space considerations, the laboratory copy was discarded after about one year. When the original form was returned to Griesser, he copied the results into his notebook and retained the originals for two or three years, after which time they were also thrown out due to shortage of filing space.
The board found the evidence regarding the laboratory test results not to be original record evidence, and held that since no person who ran the tests was called to testify, such evidence was merely hearsay.4
*750In addition, the board found that the purpose of Harding’s experimentation was to find suitable replacements for antioxidants then in use for electrical insulation compounds, and that:
“ * * * The party Harding has not made any tests in respect to the contemplated practical use in electrical wiring nor has he made any tests duplicating the working conditions in any other practical use. Mere production of the composition after one or two hours of hot milling is not a basis for predicting success in some practical use in the absence of acceptable correlating data, and there are none. * * * ” (Italics supplied.)
Hence, it concluded that Harding had not satisfied the requirements that a party seeking to prove actual reduction to practice must show that his invention worked as intended to work in its practical contemplated use, citing Elmore v. Schmitt, 278 F.2d 510, 47 CCPA 958.
The board went on to state:
“ * * * The erratic results and the necessity for further trial show that as of March 2, 1953 (the date of Exh. 9) Harding was in the realm of uncertainty in respect to practical utility. Certainly there was no conviction of success at that time.
* * * -X- *
“ * * * The statement that the ‘encouraging results * * * warrants further investigation for possible replacement of Br-254 in polyethylene electrical insulating compounds’ speaks for itself and is not such language as to denote that the composition has been successfully reduced to practice. * * * ”
It held the test results to be inconclusive, and found that the necessity for further work was recognized by Harding himself. The board concluded that the test results did not prove that the product would serve the purpose for which it was designed and that, consequently, no actual reduction to practice had been established by the evidence.
Harding supports his contention that the results are proper evidence with the following reasoning: The tests conducted by the Physical Testing Laboratory at Harding’s and Griesser’s requests were routine in nature; the results were copied on temporary laboratory report forms, from which Harding and Griesser copied them into their notebooks which are permanent records; the original lab reports, having served their purpose, are routinely destroyed or discarded due to space requirements; since accurate copies of the original results were made by Harding and Griesser, both of whom were available for cross-examination, the test results should be accepted as routine entries and accorded probative weight as evidence; and finally, they should be admitted under the Federal Shop Book Rule.
Harding contends further, that the test results establish an actual reduction to practice because they demonstrate to the satisfaction of the inventor and his associates that the test-compositions would perform their intended function in actual service. He also urges that the intended function for the composition was merely that it serve as insulating material; that such function was proved ; and that it was unnecessary to prove the composition would serve specifically as electrical wire insulation.
In the view we take of the case, Harding cannot prevail even if all of the evidence submitted on his behalf is assumed to have probative value. Hence the real question becomes whether hot milling a composition consisting of polyethylene and Santowhite Crystals, followed by the testing of plaques pressed therefrom for power factor, dielectric constant and reflectance properties constitutes an actual reduction to practice of the invention in issue.
We have considered the authorities cited by appellant, but find Elmore v. Schmitt to set out the proposition of law which is controlling. We said there:
“ * * * the record does not show that any one of the various *751tests employed by Steagall duplicated the conditions which would normally be encountered in a practical application of the invention in issue with respect to the resistance and character of load, nature of pulses, including voltage, duration and amplitude, and amount of capacitance used. Neither is it shown that the tests accurately reproduced the conditions of temperature, vibration, or sustained operation which would usually be encountered in a specific use.
“The question of sufficiency of laboratory tests to establish a reduction to practice has frequently been considered by this and other courts. Undoubtedly the general rule, * * * is that ‘A party seeking to prove actual reduction to practice must show that his invention worked as intended to work in its practical contemplated use.’ ” Gaiser v. Linder, 253 F.2d 433, 45 CCPA 846; Kruger v. Resnick, 197 F.2d 348, 39 CCPA 994, and cases there cited.
The first question is, therefore, what was the practical use to which appellant intended to put his invention. Though no specific limitation with respect to utility or purpose appears in the claims, it must nevertheless be considered. In Blicke v. Treves, 241 F.2d 718, 720, 44 CCPA 753, we said:
“ * * * A composition of matter cannot be a patentable invention unless it has utility. * * * Accordingly, the invention of such a, composition is not complete unless its utility is either obvious or is established by proper tests, regardless of whether the claims contain any specific reference to utility.
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“As noted above, neither of the counts specifies any use for the claimed compounds. While that fact alone does not eliminate the necessity of showing that the compounds have some utility, it does have a bearing on the kind of utility which must be shown. It has been held that where an interference count does not specify any particular use, evidence proving substantial utility for any purpose is sufficient to establish reduction to practice. * *” (Italics supplied.)
We have reviewed the record in order to find substantial utility for any purpose and conclude therefrom that the intended purpose was to use the composition as pigmented electrical wire insulation. That conclusion is based on statements appearing in the specification, appellant’s brief and testimony on his behalf.
Appellant’s specification states:
“It is an object of this invention to produce ethylene polymer compositions having a substantial odor, color, and electrical stability. A further object is to provide ethylene polymer compositions capable of being heat-formed into fibers, film, sheeting, wire coatings and molded articles characterized by substantial resistance to color change, odor development and electrical degradation. * * * ” (Italics supplied.)
We find not even an attempt to show reduction to practice based on any other use than electrical insulation. Appellant’s brief describes the objects as follows :
“The work with regard to the preparation of the composition of the count and the testing of the composition resulted from a program extending from 1952 into 1953 at the then Bakelite Company (now Union Carbide Plastics Company).
“The program was directed to finding an antioxidant for polyethylene electrical insulating material which exhibited better resistance to discoloring than those in use. * * *» (italics supplied.)
Harding’s pertinent testimony is:
“Q24. How was color developed in the hot processing of polyethylene compounds? What has that to do with the project or your aims? A. *752Well, it is desirable to have a very-low level of discoloration in polyethylene compounds especially for applications where the polyethylene compounds are to he pigmented for identification purposes as in wiring.” (Italics supplied.)
The pertinent testimony of Griesser, a corroborating witness, is as follows:
“Q14. Can you tell me the circumstances under which, to your knowledge, that project started and what connection you had with it?
A. Well, up until this time—
“Q15. By ‘this time’ you mean what? A. 1952. The antioxidants employed in polyethylene electrical insulating compounds were by their nature materials which discolored the base polyethylene resin, making it difficult to have colored formulation, compounds, based on those same antioxidants which were reproducible from time to time and which gave acceptable good pastel colors. The purpose of the project was to develop a better base formulation compound, based on an improved antioxidant, one which was inherently non-discoloring for use in this application.
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“Q19. What connection did you have with this project? A. It was my responsibility to develop the final product for wire coating application.
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“Q21. What was your connection with it at that time? A. At that time I became acquainted with the problem we were having in manufacturing these colored compounds and the discoloration we were getting because our sales of colored materials were increasing and it became increasingly difficult for us to manufacture uniform colors. * * * ” (Italics supplied.)
The ultimate question, therefore, becomes whether the laboratory tests establish that the composition of polyethylene and Santowhite Crystals will perform successfully as pigmented electrical wire insulation. We agree with the board that it does not. No wires or cables were insulated and tested. Furthermore, the record discloses no correlation between the laboratory results and test results under actual service conditions. In the absence of either actual service tests or positive correlation between that and simulated tests, there is no way of knowing the extent to which laboratory tests for various physical and electrical properties can be said to be predictive of the performance to be expected under actual conditions of use. Hence, it is not known whether a stabilized composition, useful for any purpose, has been achieved. That is particularly true in the instant case, since wire insulating composition would contain at least one additional element, viz, the pigment, which may affect the properties of the composition.
The evidence leaves us at a loss to know to what extent, if any, hot milling will simulate the effect produced on electrical wire insulation, when used under actual service conditions.
While the laboratory tests may have indicated promise, we do not think, and appellant’s testimony indicates that neither the inventor nor his associates thought, that success had definitely been established. It seems to us that the standard for reduction to practice, as established by the cases cited, requires more than has been done here.
Appellant argues that the case law controlling the present situation is Smith v. Swaine, 127 F.2d 140, 29 CCPA 973, and Schnick v. Fenn, 277 F.2d 935, 47 CCPA 1174, and that those cases in effect hold that reduction to practice is satisfactorily demonstrated by laboratory tests which render it reasonably certain that the subject matter will perform its intended function in actual service. We do not think those decisions conflict with Elmore v. Schmitt. From what we have already said, it should be apparent that appellant has not proved that it is reasonably certain that the inven*753tion will perform its intended function in actual operation. We agree with the board that appellant has failed to establish an actual reduction to practice prior to the filing date of the senior party.
The decision is affirmed.
Affirmed.
MARTIN, J., concurs in result only.
. Harding’s application, Serial No. 465,424, was filed October 28, 1954.
. No. 89,352.
. Steingiser et al. filed application, Serial No. 388,689, on October 27, 1953.
. In support of that holding the board relied on Teter v. Kearby, 169 F.2d 808, 36 CCPA 706, and Schering Corp. v. Marzall, D.C., 101 F.Supp. 571.