The Patent Office rejected for lack of invention certain patent claims for improvements in making flexible abrasives known as sandpaper. In suits brought by appellant under § 4915, R. S.,1 the District Court found that the claims now in issue were not patentable over the prior art.2
*594These claims are for abrasive sheets or belts, made up of a backing and an abrasive grit bonded to it. The gist of the claims is that they disclose vinyl resins as a binder. The Patent Office concedes the novelty and utility of such binders. The evidence tends to show that they impart “waterproofing, high tensile strength, lack of rotting, good ageing, at the same time good adhesion.” The Patent Office and the District Court have held that invention is lacking because the use of vinyl resins in making flexible sandpapers is taught by combining (1) sandpaper patents which disclose binders of cellulose ester, nitror cellulose composition, or cellulose material,3 and (2) patents which describe the characteristics of vinyl resins and teach their usefulness for many purposes, including impregnating purposes, for which cellulose esters and the like have been used.4 The function of the binder in sandpaper is “impregnating.” The Patent Office now urges, also, that the use of vinyl resins in flexible abrasives is in effect anticipated by the Benner patent, No. 1,825,771, which describes the use of meta-styrene or styrol as a bond in a molded or rigid abrasive. Though molded and flexible abrasives are not identical,5 neither are they wholly unrelated. Though there is much chemical authority to the contrary, some such authority supports the trial court’s finding that styrol is a vinyl compound; and styrene and styrol are specifically included in some of appellant’s applications, with more or less implication that they are “vinyl.”
Substitution of materials to produce a more efficient article may or may not amount to invention.6 The question of invention is the question whether “some uncommon talent” is shown.7 As this is a question of fact8 we are to decide not whether in our opinion there was invention, but whether the finding that there was none is consistent with the evidence 9 or, what is the same thing, is “supported by the evidence.” 10 Whatever else may be said of older decisions 11 that,, in appeals from the Patent Office, doubt was to be resolved in favor of the applicant, they are obviously not law in relation to appeals from the District Court.
Substantial evidence is “such relevant evidence as a reasonable mind might accept as adequate to support a conclusion.”12 Since the art knew vinyl binders for molded abrasives, cellulose binders for flexible abrasives, and the fact that vinyl resins will serve the impregnating or binding purposes of cellulose materials, a reasonable mind might conclude that no uncommon talent was required to conceive of vinyl resin binders for flexible abrasives. *595The fact that appellant’s claims were filed by two different persons, and other claims which appellant thinks indistinguishable from its own were filed by three other persons, in itself may suggest to a reasonable mind that the concept was within the reach of those skilled in the art. If, as appellant contends, indistinguishable claims have been allowed by the Patent Office13 on later applications, that fact is persuasive that a reasonable mind might find invention here but does not prove that the evidence requires such a finding. The inconsistent granting of other applications no more proves the office wrong in rejecting the present claims than inconsistent rejection of other applications would prove it wrong in granting claims.14 Our decision does not, of course, touch the question pf priority between appellant and others. Affirmed.
STEPHENS, Associate Justice, dissents.-