“I consider that the Skilled Person would be a graduate chemist with experience in the design, preparation and characterisation of metal oxide supported catalysts. He would have several years’ professional experience (most likely in industry) in the synthesis and characterisation of catalytic materials either at a catalyst manufacturer, an oil company or a chemicals/materials manufacturer. The Skilled Person would have knowledge of chemistry, the synthesis of metal oxides and catalysts, the characterisation of materials in general and catalysts in particular and also how these materials (metal oxides and catalysts) are applied in their particular sector of industry.”
“As discussed more fully below, the Patent is principally directed to the use of ceric oxide for purifying vehicle exhaust gas. Although the Patent explains (in [0001]) that the invention relates to “ceric oxide that has excellent heat resistance useful for catalysts, functional ceramics, solid electrolyte for fuel cells, and the like, and particularly suitable for use as a co-catalyst material in catalysts for purifying vehicle exhaust gas…” the skilled person would understand it to be concerned principally with those applications of ceric oxide where its oxygen storage capacity and thermal stability at high temperatures are important. Rhodia contends that the skilled person would recognise that the use to which the parameters of the Patent were relevant is vehicle exhaust catalysts. Individuals not working in the field of vehicle exhausts will be less interested in the Patent and the prior art than those working in the field.”
“In the case of obviousness in view of the state of the art, a key question is generally “what problem was the patentee trying to solve?”
“[0012] It is therefore an object of the present invention to provide ceric oxide that has excellent heat resistance and oxygen absorbing and desorbing capability useful as a cocatalyst material suitable for purifying exhaust gas, that is capable of maintaining a large specific surface area even in use in a high temperature environment, yet capable of exhibiting high oxygen absorbing and desorbing capability also in a lower temperature range, a method for preparing such ceric oxide, and a catalyst for purifying exhaust gas utilizing such ceric oxide. [0013] ….Thus the inventors, have made intensive efforts to increase the crystallinity of the precursor, and found out a reaction method for improving the crystallinity of the precursor at a high temperature under an oxidizing atmosphere, to thereby complete the invention.”
“Example 1 [0050] A ceric nitrate solution not less than 90 mol% cerium ions of which were tetravalent was taken so that 20g of cerium in terms of cerium oxide was contained, and the total volume was adjusted to 1 liter with pure water. Here, the concentration in terms of cerium oxide was 20 g/L. The solution was placed in an autoclave reactor, heated to 100 °C, held at this temperature for 24 hours, and allowed to cool in an atmosphere to room temperature. [0051] Then an aqueous ammonia solution was added to neutralize to pH 8 to obtain cerium oxide hydrate in the form of a slurry. The slurry was then subjected to solid-liquid separation with a Nutsche filter, followed by separation of the mother liquor, to obtain a filter cake. The filter cake was calcined at 300 °C for 10 hours in a box-type electric furnace under air atmosphere to obtain ceric oxide, which was then ground in a mortar into ceric oxide powder (referred to as powder (A) hereinbelow). The specific surface area of powder (A) was measured by the BET method. Further, the specific surface areas of powder (A) after calcination at 800 °C for 2 hours, at 900 °C for 5 hours, and at 1000 °C for 5 hours, respectively, were measured by the BET method. The tap density and total pore volume of powder (A) were also measured. Further, powder (A) was calcined at 900 °C for 5 hours, and then the OSC of the resulting ceric oxide powder was measured at 400 °C. The results of these measurements are shown in Table 1. [0052] Powder (A) was calcined at 1000 °C for 5 hours, and then the TPR measurement was made. The results are shown in Fig. 1. Further, from the TPR curve taken after calcination at 1000 °C for 5 hours, the ratio of the area (S1) defined by the baseline and the TPR curve in the temperature range of 200 to 600 °C to the area (S2) defined by the baseline and the TPR curve in the temperature range of 600 to 1000 °C, i.e., the S1/S2 ratio, was determined. The results are shown in Table 1.”
“Cerium oxide and zirconium oxide are known compounds that are particularly useful constituents, either alone or in combination, in a wide variety of catalyst compositions, e.g., multifunctional catalyst compositions, especially catalysts suited for the treatment or conversion of exhaust gases emanating from internal combustion engines.”
“Accordingly, a major object of the present invention is the provision of novel Ce0 2/Zr0 2 mixed oxides of the solid solution type, having large specific surface areas, and this over a wide range of compositions, in particular at high contents of zirconium. Another object of the present invention is the provision of such novel Ce0 2/Zr0 2 mixed oxides which retain a large specific surface area even after calcination(s) at elevated temperatures. Still another object of this invention is the provision of particular synthetic technique for the preparation of said novel Ce0 2/Zr0 2 mixed oxides.”
“8.17… Examples 1 and 3 involve neutralisation of the initial free acidity of the cerium (IV) solution and the addition of further base according to a formula which gives "a ratio of neutralisation, r" not exceeding 0.5… In examples 2, 4 and 5 the initial free acidity is not neutralised and no further base is added at this stage. 8.18. Example 1 involves a single autoclave step at 160ºC for 4 hours followed by filtration, washing with ammonia and drying at 80ºC. 8.19. Examples 2 and 3 involve a first autoclave step at 150ºC for 4 hours followed by addition of base to pH 9.5, recovery of the product by filtration, re-suspension of the solid product in water, heating to 100ºC for 1 hour and filtering off the product. 8.20. Examples 4 and 5 involve a first heating of the solution to 100ºC for 2 and a half hours, a cooling step and addition of base to pH 9 to 9.5 followed by a second heating step at 100ºC for 1 hour, cooling and recovery of product by filtration.”
“[In Hallen v Brabantia[1991] RPC 195 ] the prior art disclosed a type of corkscrew to which PTFE (the well-known non-stick plastic) had been applied to make it easier to penetrate the cork. It was obvious that the same advantage would apply to all corkscrews. What was not foreseeable was that there was an extra advantage for a “self-puller” type of corkscrew. But a PTFE coated self-puller was obvious nonetheless.”
“124. The claim appeared to assume that all uEPOs had effectively the same molecular weight, irrespective of source and method of isolation. This had been shown not to be the case. So which uEPO did the claim require to be used for the test? Simply to use the first uEPO which came to hand would turn the claim into a lottery. On the other hand, it would be burdensome to have to work one's way through several specimens of uEPO (which were, as I mentioned at the beginning of my speech, extremely hard to come by) and even then the result would be inconclusive because non constat that some untried specimen did not have a different molecular weight. 125. The judge decided that the lack of clarity made the specification insufficient. It did not merely throw up the possibility of doubtful cases but made it impossible to determine in any case whether the product fell within the claim. The invention was not disclosed “clearly enough and completely enough for it to be performed by a person skilled in the art”: section 72(1)(c). 126. The Court of Appeal disagreed. They said that it was sufficient that some uEPO could be tested against eEPO by SDS-PAGE. The fact that it did not specify which uEPO and that choosing one uEPO would bring the product within the claim and another would not was “lack of clarity dressed up to look like insufficiency.”
“61 So, for example, if a man finds a particular way of making a new substance which is 10 times harder than diamond, he cannot just claim “a substance which is 10 times harder than diamond.”
“none of the other constituents listed on the certificates of analysis are present at a level that would have a significant effect on the specific surface area of the product when measured after calcining it at 900°C for 5 hours. In particular, the amount of silicon in the Commercial Samples is less than 0.005% for C100 and less than 0.02% for C100N. These amounts of silicon are insignificant and consistent with silicon being incorporated into the Material from the original source Minerals.”