APV Anhydro A/S v Niro A/S
[2000] APO 71
•7 December 2000
OFFICIAL NOTICE
DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS
Application : No. 683514 in the name of APV ANHYDRO A/S
Title: A Process for Production of Ceramic Powders by Spray Drying
Action: Opposition under section 59 of the Patents Act 1990 by NIRO A/S
Decision: Issued .
Abstract
The opponent has not established that the claims lack novelty or inventive step. Of the documents cited against the claims, the Masters paper is the most relevant. The applicant’s approach to claiming the invention broadly by defining the invention by result rather than by defining the specific process conditions and apparatus described in the example has introduced some doubt as to the validity of the claims in light the Masters paper. However the benefit of any doubt must be given to the applicant. The Masters paper, and the other documents cited, do not disclose all features of the invention in clear, unequivocal and unmistakable terms.
The opposition has failed. Direction that the application be sealed after 30 days from the date of this decision. If the Commissioner has been served with a notice of appeal before that time, direction that sealing not occur until the appeal has been decided or discontinued.
Costs in accordance with Schedule 8 of the Patents Regulations 1991.
PATENTS ACT 1990
DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS
Re:Patent Application No. 683514 by APV ANHYDRO A/S and an opposition thereto under section 59 of the Patents Act 1990 by NIRO A/S.
BACKGROUND
APV Anhydro A/S (APV) filed patent application 683514 on 22 November 1994 under the provisions of the Patent Co-operation Treaty. The application claims an earliest priority date of 23 November 1993. The application was advertised accepted on 13 November 1997. Niro A/S (Niro) filed a notice of opposition to the grant of a patent on the application on 13 February 1998. Niro filed their statement of grounds and particulars on 13 May 1998. This statement was amended on 11 June 1998 and 27 October 1998. The opponent completed evidence in support on 13 November 1998. The applicant completed service of its evidence in answer on 3 September 1999. The opponent served its evidence in reply on 2 March 2000.
I heard the parties in Canberra on 28 June 2000. Mr Barry Hess of Counsel, assisted by Mr David Gibson, patent attorney of Freehills Carter Smith and Beadle, represented the applicant. Mr David Clarke, patent attorney of Griffith Hack & Co, represented the opponent.
The applicant sought to adduce further evidence. The further evidence was filed on 23 June 2000, although I only received the evidence immediately before the hearing.
OPPOSITION AND EVIDENCE
The opponent opposed the application on the grounds that it did not comply with subsection 18 (1) (a) or (b) of the Patents Act 1990 (ground 1), and that it did not comply with the requirements of subsection 40 (2) or 40 (3) of the Act (ground 2). The opponent particularised 12 groups of documents in relation to ground 1. The opponent also included particulars relating to the priority date of the claims and to section 40 issues. However, the opponent only pressed the grounds of lack of novelty and inventive step (subsection 18 (1) (b)) at the hearing, and only in relation to three groups of documents.
The evidence in support includes declarations by Jens Thousig Møller, a Senior Engineer in the Chemical Projects Division of Niro; and Bruce Alexander Graham, who is employed by Niro Australia Pty Ltd in the position of Sales Manager – Chemical and Pharmaceutical. The evidence in support also includes declarations by Ngaire Pettit-Young (two declarations); Paul Norup Jacobsen; Elizabeth Swan; David Gerard Clark; and another declaration by Bruce Graham. These latter declarations relate to the publication dates of various documents filed in evidence.
The evidence in answer comprises declarations by Jens Lütken Getler, Patent Manager in APV Nordic, Anhydro; and John Sydney Hall, who appears to be independent of the parties.
The evidence in reply comprises a second declaration by Møller.
The further evidence filed by the applicant is a second declaration by Hall.
THE SPECIFICATION
The invention relates to a process for producing powdered ceramic products by spray drying an aqueous suspension, including dispersants and colorants. Examples of products produced according to this process are oxides and silicates and similar of aluminium, magnesium and other metals, such as clay, ferrites, kaolin and steatite. The powdered products are used within various fields such as filler and coatings for paper, ceramics, catalyst carriers etc.
Dispersants and colorants are organic components that decompose if exposed to high temperatures for relatively long periods of time. The specification states that it is important, when drying suspensions including dispersants and colorants, to use a drying process that exposes the suspensions to a minimum of heat treatment.
The prior art includes one-stage drying of ceramic products. For example, as described in Masters K., “Spray Drying Handbook” 1991, a residual moisture content of 0.5–3% is obtained by using drying air inlet temperatures in the spray dryer of 400-600°C and outlet temperatures of 95-120°C. The produced powders are often very dusty due to a fine particle size and low free moisture content and they have poor flow properties. The specification states that it has been suggested to produce dust free and free flowing ceramic powders with large particle size and increased free moisture content in a one-stage spray drying process by operating at decreased outlet temperatures. However, powders inevitably form unacceptable lumps.
Two-stage drying is also known. The suspension is first spray dried and then further dried in a fluid bed by means of hot air. In this process, energy must be provided by means of hot air to the fluid bed.
The present invention seeks to overcome the problems of the prior art by providing a two-stage drying process that uses ambient air in the second stage. According to the specification:
In a first stage the suspension is spray dried to a powder with a free moisture content in the powder that is higher than the free moisture content in the final powder; and
In an immediately succeeding second stage, the powder is cooled evaporative with ambient air to reach its final free moisture content.
The specification states that by using this invention the powder is cooled as a consequence of evaporation of moisture in the powder. The energy required for evaporation equals the energy released when the powder is cooled. In the well-known two-stage drying process, energy must be provided by means of hot air to the first part of the fluid bed. The specification states the invention makes it possible to produce storable, homogeneous, free flowing and dustless kaolin powder with a relatively high water content. It also leads to an improved heat economy for a given product quality compared to the prior art.
The specification includes two examples. The first example is a one-stage spray drying plant as depicted in Masters K., “Spray Drying Handbook”, 5th ed. 1991 at figure 4.10a. A suspension of kaolin with 55% solids was fed to the spray dryer. The drying air inlet/outlet temperatures were 50°/95°C. The produced kaolin powder had a residual free moisture content of 0.5%. The specification states that the powder was very dusty with poor flow characteristics. It did not form lumps during storage.
The second example was performed according to the invention in two stages. The same spray dryer as in example 1 performs the first drying stage. The spray dryer inlet/outlet temperatures were 30°/70°C. From this dryer the powder falls into a fluid bed where it is fluidized with unheated ambient air at 25°C. Kaolin powder from the spray dryer chamber has 7% free moisture, which is reduced to 5% during the evaporative cooling in the fluid bed. The specification states that the powder is non-dusting with good flow properties. It does not form lumps during storage.
I note that the spray dryer inlet temperatures in the specification as filed were 500°C (example 1) and 300°C (example 2). The inlet temperatures of 50°C and 30°C in the specification as accepted are obvious mistakes.
The specification includes 10 claims. The independent claims are as follows:
A process for producing powdered ceramic products by spray drying an aqueous suspension, including dispersants and colorants, characterized in, that
(a)in a first stage the suspension is spray dried to a powder with a free moisture content in the powder that is higher than the free moisture content in the final powder,
(b)in an immediate succeeding 2nd stage the powder is cooled evaporative with ambient air to reach its final free moisture content.
An apparatus for carrying out the process according to any one of claims 1 to 5, characterized in, that it comprises a spray dryer wherein the 1st drying stage is carried out and an evaporative cooler adapted to supply ambient air directly into the powder in the 2nd stage.
A process for producing powdered ceramic products by spray drying an aqueous suspension, including dispersants and colorants or an apparatus for carrying out said process, substantially as hereinbefore described with reference to example 2 and/or the drawing.
DECISION
Evidence in Reply and Further Evidence
At the outset of the hearing, the applicant objected to the evidence in reply. The applicant contended that the evidence introduced new matter and in a lot of cases was not in reply. Exhibits JTM-2, 3, 4 and 5 of the evidence in reply had not been particularised. The applicant also stated that they had filed the further evidence in response to this evidence in reply.
The opponent responded that they would not be relying on the documents exhibited in the evidence in reply. The opponent also requested that they be given 21 days to file submissions in relation to the further evidence.
The applicant countered that they wished to put in the further evidence regardless of whether the opponent relied on the documents, as it was still open to me to consider the documents in relation to a bar to sealing of the application.
I said to the parties that I would only need to consider the further evidence and would therefore only seek submissions on the further evidence if I considered the evidence in reply to be relevant. The parties agreed to proceed on this basis.
I agree with the applicant that exhibits JTM 2, 3, 4 and 5 are not strictly evidence in reply. I am also of the view that they are not relevant. Exhibit JTM-2 is a list of spray drying systems allegedly delivered by Niro to various clients covering the years 1969 to 1973. These orders all relate to foreign countries. The information in exhibit JTM-2 does not form part of the prior art base. Exhibits JTM-3, 4 and 5 include a number of tender documents, correspondence, and technical specifications provided by Niro to clients. There is no evidence that any of the information contained in these exhibits was publicly available before the priority date of the claims. The opponent has not established that exhibits JTM-3, 4 or 5 form part of the prior art base. Therefore the documents in exhibits JTM 2, 3, 4 and 5 are not relevant to the opposition.
In light of my finding that exhibits JTM 2, 3, 4 and 5 are not evidence in reply and are not relevant, there is no need to consider the further evidence.
Novelty
The test for determining whether an invention lacks novelty is the " reverse infringement test" as stated in Meyers Taylor Pty Ltd v Vicarr Industries Ltd, (1977) CLR 228 at 235:
"The basic test for anticipation or want of novelty is the same as that for infringement and generally one can properly ask oneself whether the alleged anticipation would, if the patent were valid, constitute an infringement."
Infringement of a claim occurs where "each and every one of the essential integers" of that claim have been taken, Rodi and Wienenberger AG v Henry Showell Ltd, (1969) RPC 367 at 391.
In general, the information in the citation must be, for the purposes of “practical utility”, equal to the subsequent patent application. There must be sufficient directions in the prior document for the skilled addressee to recognise the invention and to put it into practice: Hill v Evans (1862) 6 LT 90
“Whatever, therefore is essential to the invention must be read out of the prior publication. If specific details are necessary for the practical working and real utility of the alleged invention, they must be found substantially in the prior publication ... the prior knowledge of an invention to avoid a patent must be knowledge equal to that required to be given by a specification, namely, such knowledge as will enable the public to perceive the very discovery and to carry the invention into practical use.”
Lord Westbury in Hill v Evans above, elaborating on the issue of disclosure, commented that:
“the antecedent statement must be such that a person of ordinary knowledge of the subject would at once perceive, understand and be able to apply the discovery without the necessity for further experiments.”
A more recent statement in relation to novelty is given in Nicaro Holdings Pty Ltd v Martin Engineering Co (1990) 91 ALR 513 at 517:
"It is well accepted that the prior art must disclose all features of the invention embodied in the patent in suit and must do so in clear, unequivocal and unmistakable terms. The prior art must enable the notionally skilled addressee at once to perceive and understand and be able practically to apply the discovery without the necessity of making further experiments. What ever is essential to the invention must be read out of or gleaned from the prior publications".
In assessing the teaching or disclosure of the prior art, one has to consider what the skilled addressee is being taught and what they would have done on reading the citation, General Tire & Rubber Co v Firestone Tyre & Rubber Co Ltd, (1972) RPC 457 at 485, 486:
"To anticipate the patentees claim, the prior publication must contain clear and unmistakable directions to do what the patentee claims to have invented ... A signpost, however clear, upon the road to the patentee's invention will not suffice."
Similarly, a prior disclosure will only invalidate a claim if, after having read it, the skilled addressee would, rather than could, have produced all the essential integers of the claim. See also the following passage from C. Van Der Lely N. V. v Bamfords Ltd (1963) RPC 61:
"If … the prior publication contains a direction which is capable of being carried out in a manner which would infringe the patentee's claim, but would at least be as likely to be carried out in a way that would not do so, the patentee's claim will not be anticipated."
The prior art base relied on by the opponent includes the following information detailed in the declarations of Graham and Møller:
A paper entitled “Pressbodies and Powdered Fine Ceramics by Spray Drying”, Keith Masters, Interceramex 1987 Conference, 12th-16th October 1987, Stoke-on-Trent (the Masters paper) corresponding to exhibits BAG-10 and JTM-5;
A brochure by Niro Atomizer entitled “Pressbodies and Powdered Fine Ceramics by Spray Drying” (the Niro brochure) corresponding to exhibits BAG-9 and JTM-7; and
The work of Comalco in spray drying Kaolin at Weipa, North Queensland (Comalco’s Activities) as supported by a letter from Ron Mandla to Bruce Graham (exhibit BAG-4), notes of a lecture given by Mandla (exhibit BAG-5), and a Niro tender (exhibit BAG-6).
I will discuss the disclosure of each of these documents in turn. However, it is necessary to first determine the ambit of the claimed invention, particularly in regard to evaporative cooling with ambient air.
Evaporative Cooling with Ambient Air
The operating conditions of the process are not defined by the independent claims. The claims define the powder being “cooled evaporative”. In effect, the claims are defining the process and apparatus by result. The applicant’s approach to claiming the invention broadly by defining the invention by result introduces greater uncertainty into the precise scope of the claims than if the claims had been defined by the specific process conditions and apparatus described in the specification.
However, the specification is to be read as a whole. Consequently, the description is an aid to construing the claims. In Rosedale Associated Manufacturers Ltd v Carlton Tyre Saving Co Ltd [1960] RPC 59 at 69, it was stated:
"It is clearly … legitimate and appropriate in approaching the construction of claims to read the specificaiton as a whole. Thereby the necessary background is obtained and in some cases the meaning of the words used in the claims may be affected or defined by what is said in the body of the specification"
Further, the specification is to be construed in the light of the common general knowledge in the relevant art at the priority date of the application. For example, see Welch Perrin v Worrel (1961-62) 106 CLR 588 at 610, which states:
"If it is impossible to ascertain what the invention is from a fair reading of the specification as a whole, that, of course, is an end of the matter. But this objection is not established by reading the specification in the abstract. It must be construed in the light of the common general knowledge in the art before the priority date."
It is therefore necessary for me to consider the description of the invention as well as the state of the art to resolve any possible ambiguity or uncertainty in the scope of the claims.
The invention involves drying the ceramic product in two stages. In the first stage, the powder is dried to an initial moisture content in a spray dryer. The specification describes controlling the outlet air from the spray drier to within the range of 50°-100°C to control the moisture content of the powder leaving the first stage (defined in claims 4 and 5). The powder is then immediately “cooled evaporative”, that is, cooled and dried with ambient air in a second stage. The evaporative cooling is preferably carried out in a fluid bed (defined in claim 7).
According to the applicant’s evidence, the essential components of the invention are a spray dryer coupled to a subsequent dryer, especially a fluid bed dryer. Such arrangements of process equipment are well known. However, the invention is distinguished from the prior art by requiring the equipment arrangement to provide evaporative cooling without heating during the second-stage drying step to dry and cool the product to predetermined moisture levels and temperature. Normally, in known two stage processes, the second stage dryer operates by providing heated air rather than ambient air. The invention changes the focus from the equipment to the conditions under which the equipment operates and the effect that has on the product. This applies to both the process claims and the apparatus claims, in which the equipment for the second stage is defined as an evaporative cooler adapted to supply ambient air. This definition limits the second stage equipment to an “evaporative” cooler, being a limitation on how the equipment operates and the effect that has on the product.
The applicant’s evidence also states that “the phenomenon of evaporative cooling of a moist powder occurs when the moisture in the powder is brought in contact with air that has a water activity (relative moisture) lower than the equilibrium water activity of the moist powder. As air and moisture remain in contact, the heat required for evaporation is taken from the powder causing the powder to be cooled. If the right conditions are present the air may even be cooled too. The amount of cooling that can be accomplished through the evaporative cooling process depends among other factors on the relative humidity of the air – the dryer the air, the greater the evaporative cooling potential.” (Getler, paragraph 15).
The applicant also contends that “evaporative cooling” is not synonymous to “cooling” in the sense that cooling a powder with ambient air (e.g. in a fluid bed) does not automatically result in a reduction of the moisture content of the powder. While Getler concedes in a number of places in his evidence that one-stage drying plus powder cooling with ambient air is conventional, his evidence is that this is not the same as two-stage drying where the second stage involves evaporative cooling with ambient air.
The opponent submitted that evaporative cooling is inevitable when ambient air comes into contact with spray dried ceramic such as that disclosed in the opposed specification. That is, for the ceramic products and for the moisture contents in question, with sufficient loosely bound moisture, evaporative cooling will naturally occur. The ambient air is heated by the close contact with the spray dried ceramic product whereby it becomes able to contain more moisture than if it had not been heated. The spray dried ceramic product gives off moisture to the ambient cooling air so that the product is at the same time cooled and gives up some moisture whereby it is evaporatively cooled. (Møller, evidence in reply, paragraph 5). The opponent argues that admission of ambient air under the conditions described will naturally result in evaporative cooling. I note that Hall also states that “operating with conditions identical to the conditions in the second stage of the present invention leads to the evaporative cooling and drying of ceramic products …”.
Møller states that in his opinion, “it would have been well known to workers in this field that use of an ambient air powder cooler results in a reduction of residual moisture in the powder. A reduction of the order of about one percent point is typical”. However, I note all of Møller’s experience is outside Australia, and this opinion is not supported by any other evidence. Møller also states that in his opinion, the use of ambient air for cooling would have been a routine choice for workers in this field. He refers to the 4th edition of the Spray Drying Handbook, which states that ambient air is generally used for cooling, but special cooling requirements often need dehumidified, cooled air. The passage of the Spray Drying Handbook Møller refers to deals specifically with applications in the food industry. Graham also refers to this passage and says that he would also expect it to extend to spray drying of other materials including ceramics. Hall deals in detail with the differences between spray drying ceramics and food products, particularly milk products. It is clear there are significant differences between spray drying food products such as milk powder and spray drying ceramics.
The known two-stage spray drying layouts are set out in the “Spray Drying Handbook”, fourth edition, K. Masters, 1985 at pages 47-51. It was common ground between the parties that both the fourth and fifth editions of the Spray Drying Handbook formed part of the common general knowledge in the art. This reference states that the need for improved product quality and high thermal efficiency has brought about the development of two-stage systems. In a two-stage layout, spray dryers are combined with a fluid bed acting as after-dryers or coolers. There are four areas where two-stage dryer systems are used to advantage:
To achieve low residual moisture content in the powder. When very low residual moisture is required, the product is treated in controlled conditions in an externally mounted fluid bed, where the residence time of the product is much longer than in the spray dryer. Achieving low moisture content depends on the humidity of the drying air used in the fluid bed. In many cases dehumidification equipment is required to provide suitable drying air.
To obtain low powder temperatures. When powder must be cooled to a certain level prior to packing or storage, a fluid bed attached to the spray dryer acts as an effective continuous powder cooler. Atmospheric air is generally used if minimum powder temperatures of 50°C are required. Below 50°C, conditional cool air may be required.
To achieve changes in powder particle size distribution, either by classification or agglomeration. For classification duties the fluidizing velocity can be adjusted to control fines elutriation. For agglomeration duties, the spray drier is operated at a lower outlet temperature to obtain a moist product of agglomerate form that is after-dried in a fluid bed. Fines elutriated from the fluid bed can be returned to the drying chamber for further agglomeration.
To improve the thermal efficiency of the drying process. The product is taken from the dryer base at a lower outlet temperature and hence at a higher moisture content. The powder is transferred to the external fluid bed where the drying is completed. The higher inlet temperature and lower outlet temperature gives improved thermal efficiency without loss of product quality. The accompanying data clearly show the drying air to the fluid bed is heated to 130°C.
The only mention of using ambient air in the above-mentioned reference is in relation to cooling only, when low powder temperatures are required. There is no suggestion in the Spray Drying Handbook that drying will also occur when atmospheric air is used. In fact, the disclosure in relation to improving thermal efficiency, which appears to be the main object of the present invention, suggests that heated air is required to carry out the necessary second stage drying. In the absence of an explicit disclosure of evaporative cooling with ambient air in the prior art documents cited by the opponent, I need to compare the conditions disclosed in the prior art references with those described by the specification to determine if the process is implicitly disclosed.
The Masters Paper
This paper discusses spray drying ceramic powders. In the paper, Masters explains that spray drying involves the atomization of ceramic feedstocks into sprays of droplets which are dried to individual powder particles on contact with hot air. Evaporation rates during the initial drying (constant rate) period are very high, and although there is the characteristic fall-off during the subsequent falling rate period, the completion of drying is accomplished in less than a minute. During spray drying, four process stages are featured in the drying chamber:
· atomization;
· spray – hot air contact;
· evaporation, particle shape formation, drying; and
· dried product separation from drying air, discharge.
In ceramics drying, two atomizer types may be used in the atomization stage depending upon the operation – rotary atomizers or pressure atomizers.
The second process stage of spray – hot air contact is characterized by how droplets and drying air are initially contacted and how the product moves through the drying chamber. For ceramic drying, two chamber designs are used: co-current drying chamber with rotary atomizer; or mixed flow drying chamber with nozzle atomizer.
The third process stage is evaporation, which takes place from the saturated vapour film which is quickly established at the droplet surface. Droplet surface temperatures are low, approximating to the wet bulb temperatures of the drying air. Evaporation takes place under so-called constant and falling rate conditions. Masters states that “dryer chamber design must provide a sufficient droplet residence time to enable completion of moisture removal.”
The final process stage is the separation of airborne particles from the air in the drying chamber.
Masters states that the inlet and outlet drying temperatures are set to maximise thermal efficiency and obtain precise and reproducible residual moisture content in the final press powder. In spray drying ceramics for wall/floor tiles, “the spray dryer is operated at low outlet temperature to achieve a powder of residual moisture content of 6-8%”.
Figure 7 of the Masters paper shows a typical arrangement of a spray dryer with a rotary atomizer. Masters states that the “dried press powder leaves the base of the drying chamber via a powder cooler. Cooling and conditioning is essential to prevent handling problems in the subsequent storage due to the relatively high residual moisture content (6-8%) desired of the press powder leaving the drying chamber.”
Figure 8 of the Masters paper shows a typical dryer with a nozzle atomizer. This arrangement also includes discharging the powder from the dryer via a powder cooler. Figure 8 shows what appear to be horizontal slots on the powder cooler. The opponent’s experts insist that the powder cooler draws in ambient air. The applicant’s experts say that there is no indication of ambient air being drawn into this chamber. However, given Getler’s repeated acknowledgement that cooling with ambient air in a powder cooler is conventional, it appears more likely than not that Figure 8 shows this conventional arrangement whereby the external (ambient) air is drawn into the cooler.
There is a specific reference in the Masters paper that dryer chamber design must provide a sufficient droplet residence time to enable completion of moisture removal. However, Masters also states that cooling and conditioning of the dried powder is essential to prevent handling problems.
The expert evidence in relation to “conditioning” is not particularly helpful. Møller concentrates on the Figures that show a powder cooler at the bottom of the spray dryer. He suggests that the cooler is arranged freely in the room so that it is supplied with ambient air. Møller believes this adequately teaches evaporative cooling with ambient air. Graham states that, from the passage referring to cooling and conditioning, he would imply free moisture contents of the powder from the spray drier of between 1 – 2% higher than the free moisture content in the final powder following evaporative cooling. Graham does not state his basis for this implication, other than his belief that evaporative cooling will occur in the powder cooler. Given the similarity between Graham’s implied moisture reduction and the moisture contents of example 2 of the opposed application, Mr Graham’s interpretation may have been coloured with the benefit of hindsight. Getler states that “conditioning” is not defined, but does not venture an opinion as to what it means. He merely states that “evaporative cooling” is not disclosed, either explicitly or implicitly. Hall states that there is no teaching of evaporative cooling with ambient air in the Masters paper. He does not agree that controllable evaporative cooling with ambient air is achieved in the lower chamber of the spray dryer. Hall also declares that evaporative cooling and drying would generally only apply to partially dried ceramic powders. When discussing the opposed invention and the role of capillaries in the granules driving the drying and cooling rates, Hall says that “cooling and conditioning functions are elevated to a more important role than previously, whereas previously drying alone was of primary concern”. The opponent pointed to this passage as an acknowledgement that “conditioning” and “drying” were the same thing.
It appears from the evidence that “conditioning” may include drying. However, it may possibly also mean a number of things, such as controlling fines or agglomeration, as discussed in the Spray Drying Handbook. On the other hand, there is a clear teaching in the Masters paper that there is a characteristic fall-off in evaporation rates in the drying chamber. There is also a clear disclosure that dryer chamber design must provide a sufficient droplet residence time to enable completion of moisture removal. It appears that if there is any evaporation in the powder cooler formed at the bottom section of the spray dryer, this evaporation is unintentional and/or seen as part of the first stage drying in the spray dryer. The Masters paper makes no reference to drying in two stages. In my view, the opponent has not established that the claims lack novelty in light of the Masters paper.
The Niro Brochure
According to the Jacobsen declaration, this brochure was originally issued on 30 May 1986 and distributed in the Niro organisation worldwide and to customers in the ceramic industry and displayed at conferences and exhibitions from 30 May 1986. I am satisfied that this document forms part of the prior art base.
This brochure states that the majority of wall and floor tiles, electronic and fine ceramics are made from spray dried pressbodies. Pressbodies consist of free-flowing, spherical shaped particles which are ideal for pressing, transportation, metering, sintering, and in other powder processing. Spray drying maintains a constant pressbody moisture content and bulk density level during continuous production runs – an important factor in quality reproducibility. Fine ceramics are produced according to individual particle size requirements (mean size range 30 – 300 micron) by selective use of rotary or nozzle atomization.
The brochure includes a number of photographs and drawings of spray dryers. A number of the spray dryers shown have powder coolers at the bottom of the spray dryer. Vertical lines can be seen on the photograph of the powder cooler and are also shown on those drawings including a powder cooler. These lines appear to be vertical slots. The brochure also briefly describes system selection for different applications. The brochure states in several of these applications that the dried pressbody leaves the base of the drying chamber via a powder cooler. Although Getler states in his declaration that no inlets for ambient air are seen in the brochure, he acknowledges at several places in his declaration that material from the spray dryer may be subjected to a conventional powder cooling step with ambient air (for example, at paragraph 62).
One of the drawings shows a fluid bed at the outlet of the spray dryer. Although Getler suggests that the “unidentified apparatus” in the drawing is not necessarily a fluid bed and could “just as well be a powder cooler”, I place little weight on this suggestion. The brochure also includes a box showing areas of Niro Atomizer technology. This box includes associated processing, including fluid bed coolers for cooling powders from spray and fluid bed dryers. However, there is no disclosure in the brochure as to whether the fluid bed dryers are fed with ambient air or are fed with heated air as in the acknowledged prior art. The brochure also lacks any detail on the process conditions under which the spray dryers shown are to be operated.
The brochure does not contain directions to spray dry a ceramic powder to a first moisture content in a spray dryer then to immediately evaporatively cool the powder to its final moisture content in a second stage. The brochure does not therefore disclose all the essential integers of the claims. The claims are novel in light of the Niro brochure.
Comalco’s Activities
The opponent filed a group of documents relating to the operation of a kaolin plant operated by Comalco in North Queensland. The applicant objected to the inclusion of this evidence on the basis that it was not included in the amended statement of grounds and particulars. The statement as originally filed and as amended on 11 June 1998 included reference to a proposal and trials for the inclusion of 2 stage drying in an existing kaolin spray dryer for Comalco Australia Ltd. However, this reference was omitted from the statement when it was further amended on 27 October 1998. This provides a strong basis not to consider the Comalco documents. However, I am reluctant to dismiss the documents altogether if doing so would lead to the grant of an invalid patent.
Exhibit BAG-4 includes a letter from Ron Mandla, Manager – Special Projects, Comalco, to Mr Graham. The letter is dated 22 July 1998. In the letter, Mr Mandla states Comalco were operating a kaolin plant at Weipa, North Queensland from October 1986 to November 1996. Mr Mandla states that Comalco did studies to determine the best method of cooling the product from the spray dryer based on the principle of using ambient air as the coolant. Attached to the letter is a tender price dated 20.05.91 from Niro, apparently relating to the project (also reproduced at BAG-6). For “various reasons”, Comalco did not proceed with this project.
There is no evidence that the studies done by Comalco were publicly available information. The opponent has not established that the documents exhibited in BAG-4 and BAG-6, and the studies referred to therein, formed part of the prior art base at the priority date of the claims. Therefore these documents are not relevant to the opposition and I need not consider them any further.
Exhibit BAG-5 is a copy of lecture notes handed out at a lecture given by Mr Mandla entitled “Spray Drying of Kaolin”. The lecture notes are undated. Mr Graham states that he “attended this lecture and obtained the lecture notes several years before the earliest priority date”. The earliest priority date of the application is 23 November 1993. Mr Graham’s declaration is dated 30 October 1998, nearly five years after the priority date. The fact that Mr Graham is unable to identify even a year in which the lecture notes were published places some uncertainty on the publication date of the notes and the date of the lecture.
On the basis of publication date alone, the opponent has not made out its case to the required standard of proof. In any case, I consider that the lecture notes do not contain an adequate disclosure to deprive the claims of novelty. The lecture notes discuss the Comalco Kaolin plant in Weipa, North Queensland. A spray dryer converts kaolin slurry at 66% solids to a product having a consistent moisture content of approximately 2%. The product temperature must be maintained below 120°C. The notes state that the product from the spray dryer is cooled by atmospheric air admitted at the discharge chamber of the spray dryer before discharge to a vibratory screen to remove lumps in excess of 2 mm.
The Mandla notes describe material having a traditional moisture content (1-3%) that is subjected to a conventional cooling step with ambient air. Mandla does not describe two stage drying in which the powder from stage 1 is subjected to evaporative cooling with ambient air in stage 2.
The opponent said that Table 1 refers to an exhaust gas temperature of between 90 and 140°C depending on the product moisture content. The opponent argued that in the context of ceramic tiles, the product is dried to a water content of about 6% at an outlet temperature of between 90 to 100°C, as variously stated throughout the evidence. However the Mandla lecture notes are not in the context of ceramic tiles. The Mandla notes clearly state that the Comalco plant is for production of Kaolin suitable for the paper coating industry. It is clearly stated throughout the notes that the moisture content of the product is about 2%, and the reference to “depending on product moisture content” in the spray dryer process parameters can only be read in this context. There is no disclosure or suggestion in the Mandla lecture notes that the Weipa plant can be adapted to produce a ceramic powder with a moisture content of 6%.
Therefore, even leaving aside the doubts over the publication date and the omission of this document from the statement of grounds and particulars, the Mandla lecture notes do not disclose all features of the invention embodied in the application in clear, unequivocal and unmistakable terms. The notes do not contain clear and unmistakable directions of a two stage process in which a suspension is spray dried to a first moisture content and in an immediate succeeding second stage is cooled evaporative with ambient air to reach a final moisture content.
Inventive Step
Section 7(2) of the Patents Act 1990 specifies that an invention is taken to involve an inventive step when compared with the prior art base unless the invention would have been obvious to a person skilled in the relevant art in the light of the common general knowledge as it existed in the patent area before the priority date of the relevant claim, whether that knowledge is considered separately or together with either of the kinds of information mentioned in subsection (3), each of which must be considered separately.
The opponent submitted that the invention was obvious to a person skilled in the art of spray drying powders in light of their common general knowledge at the earliest priority date. This common general knowledge may be considered together with information that the person skilled in the art could reasonably be expected to ascertain, understand and consider as relevant. In this regard the opponent relied on evidence provided by the declarants including the Masters paper, the Niro brochure, Comalco’s activities, the 4th and 5th editions of the Spray Drying Handbook and acknowledgements made by the applicant within the specification itself.
The opponent submitted that the common general knowledge included the Spray Drying Handbook and US patent number 3,867,234, which were referred to in the application. The applicant agreed that the Spray Drying Handbook was part of the common general knowledge. The applicant also conceded that in light of the decision in Bristol-Myers Squibb Co v F H Faulding & Co Ltd 170 ALR 439, the US patent was probably also common general knowledge.
The opponent’s case in relation to inventive step was similar to its case in relation to novelty. They stated that Hall acknowledged that the arrangement of a spray dryer coupled to a subsequent dryer, especially a fluid bed dryer, is well known in the process arena of agglomeration practice. The opponent also pointed out that Getler declared that “it may be correct that the use of ambient air for cooling would have been a routine choice for workers in this field at 23 November 1993”. The opponent concluded that evaporative cooling and drying would, by Getler and Hall, be expected to occur under the operating conditions outlined in at least the Masters paper and the 4th and 5th editions of the Spray Drying Handbook. The opponent draws this conclusion on the basis of the Møller declaration, in which Møller declares that evaporative cooling is inevitable when ambient air is taken or comes into contact with spray dried ceramics such as those disclosed in the opposed application.
Hall states that conventional practice as applied to ceramics would assume the path of addition of heat in the second stage to dry quickly and less thought would be given to cooling or moisture migration and condensation. Hall states that before reading the opposed application, he would have been unlikely to see that ceramic powder granules would benefit from or need “evaporative cooling” due to the presence of an underlying definite and unchanging pore structure. Hall states that “on reading of it in the specification, I say, “yes, of course”, “I wish I had thought of that”. It has a clear connection to exploiting the capillaries to drive the drying and cooling rates of a moist granule”.
I have already considered the state of the art in relation to two stage processes as set out in the Spray Drying Handbook. As I have stated above, the only mention of using ambient air in the Spray Drying Handbook in two-stage layouts is in relation to cooling only, when low powder temperatures are required. When drying is required in the second stage to improve thermal efficiency, the Spray Drying Handbook teaches that heated air is required. US 3,867,234 describes a fluid bed in conjunction with a spray dryer. However the fluid bed is present to improve separation of the dried product by guiding the dry powder to the discharge outlet with ambient air. The US patent does not address cooling or drying as the powder is already dried before being introduced to the improved separation stage.
The opponent has not made out its case that the claims lack an inventive step in light of the common general knowledge, whether that knowledge is considered alone or together with the information in any of the documents filed in evidence.
CONCLUSION
The opponent has not established that the claims lack novelty or inventive step. Of the documents cited against the claims, the Masters paper is the most relevant. The applicant’s approach to claiming the invention broadly by defining the invention by result rather than by defining the specific process conditions and apparatus described in the example has introduced some doubt as to the validity of the claims. While the distinction between the claims and the prior art would be more definite if the particular apparatus and operating conditions described by example 2 were defined in the independent claims, the applicant is entitled in this case to claim by result (No-Fume Ltd v Frank Pitchford and Co. Ltd. (1935) 52 R.P.C. 231). Further, any doubt as to the validity of the claims must be resolved in favour of the applicant, as is well-established law (see, for example, Hoffman - La Roche A G v New England Biolabs Inc [2000] FCA 283 (28 April 2000). In light of this, while the Masters paper provides a signpost upon the road to the applicant's invention, it does not contain clear and unmistakable directions to do what the applicant claims to have invented. That is, the Masters paper does not clearly and unmistakably disclose a two stage process in which powder is dried to a first moisture content in a spray dryer then evaporatively cooled with ambient air in a second stage. On the basis of the evidence, I cannot conclude that the specific details necessary for the practical working and real utility of the invention are to be found in the prior publication. The Masters paper does not disclose all features of the invention in clear, unequivocal and unmistakable terms. It follows that the opponent has not established that the Masters paper would constitute an infringement of the claimed invention.
I find the opposition has failed. Accordingly I direct the application be sealed after 30 days from the date of this decision. If the Commissioner has been served with a notice of appeal before that time, I direct that sealing not occur until the appeal has been decided or discontinued.
COSTS
The normal practice in hearings before the Commissioner of Patents is for costs to follow the event. The opponent argued that if the applicant was successful, the applicant should only be entitled to costs for attendance of a patent attorney at the hearing and should not be entitled to costs for Counsel. The schedule of costs set out in Schedule 8 of the Patent Regulations 1991 allow Counsel fees for attendance at a hearing as well as costs for the attendance at a hearing by registered patent attorney or solicitor instructing counsel. In my view, the nature of the evidence and the objections raised in the statement of grounds and particulars justified the use of Counsel in the present case. I see no need in the present circumstances for departing from the scheduled costs.
I award costs in accordance with Schedule 8 of the Patents Regulations 1991.
Brendan Bourke
Delegate of the Commissioner of Patents
Patent attorneys for the applicant : Freehills Carter Smith and Beadle, Melbourne
Patent attorneys for the opponent : Griffith Hack & Co, Sydney
0
2
0