Ductmate Industries Inc. v.
's evidence, on examination for discovery which was read into the record at trial, was that when Ductmate first started manufacturing, it used a string type gasket material which was placed in the frame flange pocket as the flange was roll formed. It then abandoned this material in favour of a liquid type sealant, not one found on the commercial market but one made especially for Ductmate. This too proved to be inadequate because it hardened too quickly. A second and then a third type of liquid (or paste-like) sealant was tried until one having appropriate characteristics was found. When asked for the specifications of the liquid (paste-like) sealants Mr. Arnoldt 's answer was that this constituted a trade secret.
The advantage of a mastic of appropriate viscosity is threefold; it allows the mastic to flow around the duct edge; it allows the duct edge to abut, or approximately abut, the interior wall of the frame flange (allowing maximum penetration of the duct into the external gasket in the corner region of the assembly); it will extrude from the edges of the frame flange so as to create a seal with the corner piece.
A material which is "paste-like" can have a wide variety of properties. It can have the characteristics of putty which hardens over the course of time; it can have the consistency of ordinary mucilage or wall-paper paste. Mr. Whipps
'evidence concerning the variety of commercial products in tubes and cans which he thought might be used and could be found by trying them is not sufficient to ground a conclusion that only routine testing would be required to find the appropriate product. Also, his assertion that it would only require trying to find an appropriate product was given in the course of this trial after Ductmate had finally settled on a material for use in the frame flange. If the characteristics and specifications of the material had been given in the patent I could conclude that only routine testing would be required, but in the absence of such guidelines. I cannot, on the basis of all the evidence in this case, including Mr. Whipps 'evidence, I cannot conclude that the sealant to be placed in the pocket of the frame flange has been described adequately. Accordingly, I hold this element of the patent invalid as lacking the degree of specificity required to satisfy s. 36(1) of the Patent Act, R.S.C. 1970, c. P-4.
"One issue relating to the evidence remains to be considered. Correspondence sent on behalf of Mr. Sullivan to the patent office concerning changes requested to the patent as originally filed, and respecting the status of his claim before the United States patent office, was proffered as admissible and relevant evidence. I reserved decision on its admissibility. It is clear that the documents are not admissible: refer Dominion Rubber Co. Ltd. v. Acton Rubber Ltd. (1963), 42 C.P.R. 7, 24 Fox Pat. C. 131 at p. 136 (Ex. Ct.); and Riddell v. Patrick Harrison & Co. Ltd. (1957) 28 C.P.R. 85, 17 Fox Pat. C. 83 at p. 122 and at pp. 123-4."