Western Minerals Technology Pty Ltd v Western Mining Corporation Limited
[2001] APO 32
•12 July 2001
OFFICIAL NOTICE
DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS
Application : No. 663525 in the name of WESTERN MINERALS TECHNOLOGY PTY LTD
Title: ACTIVATION OF A MINERAL SPECIES
Action: Opposition under section 59 of the Patents Act 1990 by WESTERN MINING CORPORATION LIMITED
Decision: Issued .
Abstract
The opponent had raised grounds of novelty, inventive step, manner of manufacture and fair
basis.The grounds of manner of manufacture and lack of fair basis have not been proven.
The opponent has been successful on the grounds of lack of novelty and inventive step.
Under the grounds of novelty and inventive step the issue of a learned society was
considered, as per section 24, in the matter of a paper read (by the inventors) at a conference
and published at a later date. The conference and publication were carried out by and on
behalf of the Camborne School of Mines. The Camborne School of Mines was found not to
satisfy the requirements to be treated as a learned society. The conference of itself was also
not considered to constitute a learned society. Thus the paper read by the inventors and
published on their behalf could properly be considered for the purposes of novelty and
inventive step.
All the claims of the opposed application were found to lack novelty and inventive step in
light of the publication of the Corrans and Angove paper.
No patentable subject matter found in the opposed application. Application refused.
The applicant and opponent are directed to file their submissions on costs within two weeks
of the date of issue of this decision.
PATENTS ACT 1990
DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS
Re:Patent Application No. 663525 by WESTERN MINERALS TECHNOLOGY PTY LTD and opposition under section 59 of the Patents Act 1990 by WESTERN MINING CORPORATION LIMITED.
BACKGROUND
Dominion Mining Limited, now Western Minerals Technology Pty Ltd (WMT) filed patent application 27182/92 on 20 October 1992 associated with Australian Provisional Patent applications PK9121 and PL3016 filed 25 October 1991 and 17 June 1992 respectively. The application was advertised as accepted on 12 October 1995 under the No. 663525.
Subsequently four parties filed notices of opposition of which one was dismissed and two subsequently withdrew their oppositions. The only remaining opponent was Western Mining Corporation Limited (WMCL) which opposed the grant of a patent on the application on 12 January 1996.
During the opposition process WMT requested leave to amend the specification of patent application 663525 on 10 April 1997. This was finally allowed by a decision of the delegate of the Commissioner dated 21 September 2000 ([2000] APO 59).
The parties completed the service of evidence in respect of this opposition on 20 December 2000.
The hearing was held in Canberra on 19 April 2001. Bruce Caine of counsel and Peter Caporn, patent attorney of Wray & Associates, Perth, represented the applicant (WMT). Also present on behalf of the applicant was Gary Johnson. David Catterns, senior counsel, David Clark, patent attorney and Andreas Hartmann (observer) of Griffith Hack, Sydney, represented the opponent (WMCL).
STATEMENT OF GROUNDS AND PARTICULARS
WMCL filed a statement of grounds and particulars dated 12 April 1996. They contended that the invention lacked novelty, did not involve an inventive step and did not constitute a manner of new manufacture. They also submitted that the specification did not comply with the requirements of Section 40.
EVIDENCE
Evidence in support consists of the following declarations:
David John Honey, dated 11 July 1996 and exhibits DJH 1 to 8. He states that he possesses a PhD in Chemistry from the University of Western Australia and is currently employed as Group Leader, Hydrometallurgy by WMC Resources Ltd.
Gordon M. Ritcey, dated 16 May 1996 and exhibits GMR 1 to 3. He states that he has a BSc degree from the University of Dalhousie, Canada and a Doctorate of Applied Science from the University of Melbourne, Australia. He states that he is currently working as an independent and private consultant in the field of hydrometallurgy.
David Michael Muir, dated 11 July 1996 and exhibits DMM 1 to 7. He states that he has a BSc and PhD from the University of Bristol and since graduating has worked mainly in the field of hydrometallurgy. He states that he is currently working as Principal Scientist, Nickel Technology Division for WMC Resources Ltd and that he is also an Adjunct Professor at Murdoch University.
Further evidence (allowed by a decision of a delegate of the Commissioner dated 17 March 1998 ([1998] APO 11)) consists of:
Three declarations relating to availability of certain documents in various libraries.
Evidence in answer consists of the following declarations:
John Ernest Angove, dated 11 June 1997 and exhibits JEA-1 to 4. He states that he has a B App Sc (Metallurgy) from the Curtin University of Technology and is currently working as the General Manager and Director of Oretest Pty Ltd.
Gary Donald Johnson, dated 26 June 1997 and exhibits GDJ-1 to 3. He states that he has an Associate Diploma of Metallurgy from Wollongong Technical College and is currently employed as General Manager, Technology with Dominion Mining Limited (now WMT).
Ian James Corrans, dated 19 June 1997 and exhibit IJC-1. He states that he has a PhD in Chemical Engineering from the University of Natal and is currently the Technical Director of Oretest Pty Ltd.
Lyn Geoffrey Bernard Wadley, dated 24 June 1997 and exhibits LGBW-1 to 4. He states that he has a PhD in physical and inorganic chemistry from the University of Western Australia and is currently the general Manager and Company Secretary of Curtin Consultancy Services.
Ronald F Blanks, dated 19 June 1997 and exhibit RFB-1. He states that he has a PhD in extractive metallurgy from the University of Melbourne and is currently principal of Metskill Australia.
Rodney D Elvish, dated 24 June 1997 and exhibit RDE-1. He states that he has an Associate Diploma of Metallurgy and a Fellowship Diploma of Primary Metallurgy from RMIT and is currently employed as a consultant metallurgist.
Barry A Wills, dated 16 June 1997 and exhibits BAW-1 to 3. He states that he was the senior lecturer at the Camborne School of Mines in Cornwall, England during 1991 and up to March 1996. He further states that he is currently employed as an independent consultant working in the area of mineral processing and extractive metallurgy.
Evidence in reply consists of the following declarations:
John Harmsworth Canterford, dated 16 December 2000 and exhibits JHC-1 to 13. He states that he has a PhD from the University of Melbourne, is currently running his own consulting company (Process Technologies Australia Pty Ltd) and is also a Technical Director for DevMin Consultants Pty Ltd.
Keith Russell Weller, dated 18 December 2000 and exhibits KRW 1 to 7. He states that he has a PhD from the University of Adelaide and is currently a consultant metallurgist working as a sole trader.
SPECIFICATION
The invention of the specification is directed to a method for the activation of a mineral species prior to the processing of that mineral species by methods of oxidative hydrometallurgy such as by oxidative leaching. The specification identifies the mineral species as sulphides, arsenides or tellurides or any other like mineral species. The specification identifies the defects of the prior art as follows:
· Oxidative leaching processes usually require severe physico-chemical conditions in order to achieve acceptable rates of oxidation and/or final recoveries of metal,
· Severe physico-chemical conditions often mean temperatures in excess of 200oC and total pressures in excess of 2000kPa,
· The chemical reactions which occur use large quantities of oxygen, both on stoichiometric considerations and in practice where amounts in excess of stoichiometric requirements are used,
· Costly high maintenance equipment and sophisticated technology.
And then states:
"It is an aim of the present invention to avoid, or at least partly alleviate, the difficulties and expenses referred to above with traditional processing methods of oxidative hydrometallurgy, and in particular with the oxidative leaching of a mineral species."
The consistory statement defines the invention as:
"A method of processing a sulphide mineral, said method comprising the steps of:
(i) milling the sulphide mineral in a vertical stirred mill to P80 in the range from 2 to 30 micron to produce an activated sulphide mineral; and
(ii) oxidatively leaching the activated sulphide mineral in oxygen at a temperature less than about 120oC and at an oxygen pressure less than about 1000kPa for a time in the range of from 15 to 150 minutes, such that elemental sulphur is the predominant sulphur product formed."
The specification ends with eight claims as follows:
"1. A method of processing a sulphide mineral, said method comprising the steps of:
(i) milling the sulphide mineral in a vertical stirred mill to P80 in the range from 2 to 30 micron to produce an activated sulphide mineral; and
(ii) oxidatively leaching the activated sulphide mineral in oxygen at a temperature less than about 120oC and at an oxygen pressure less than about 1000kPa for a time in the range of from 15 to 150 minutes, such that elemental sulphur is the predominant sulphur product formed.
2. A method according to claim 1, wherein the milling is conducted as wet milling.
3. A method according to claim 1 or 2, wherein the sulphide mineral is milled to be in the range of P80 from 2 to 20 micron.
4. A method according to claim 1 or claim 2, wherein the sulphide mineral is milled to be in the range of P80 from 2 to 15 micron.
5. A method according to any one of claims 1 to 4, wherein the temperature of the oxidative leach is in the range of from 80oC to 120oC.
6. A method according to any one of claims 1 to 5, wherein the oxygen pressure of the oxidative leach is in the range of from 200 to 1000kPa.
7. A method according to any one of claims 1 to 6, wherein the time of the oxidative leach is from 30 to 120 minutes.
8. A method according to claim 1 substantially as herein described in relation to any one of the Examples."
SUBMISSIONS
I shall refer to the submissions from both parties wherever necessary in my decision.
DECISION
Lack of Novelty
The reverse infringement test from Meyers Taylor Pty Ltd v Vicarr Industries Ltd (1976) 137 CLR 228 at 235 sets out the basic test for anticipation or want of novelty:
"The basic test for anticipation or want of novelty is the same as that for infringement and generally one can ask oneself whether the alleged anticipation would, if the patent were valid, constitute an infringement."
It follows from the reverse infringement test that if a citation discloses all the features of the claim, the claim will lack novelty. If the citation does not disclose all the features of the claim, the claim will still lack novelty provided the citation discloses all the essential features of the claim; but if the essential features are not disclosed in the citation, the claim is novel (Nicaro Holdings v Martin Engineering 16 IPR 545 and Catnic Components Ltd v Hill and Smith Ltd (1982) RPC 183).
I shall begin by assuming that all features of the independent claims are essential (Catnic Components Ltd v Hill and Smith Ltd (1982) RPC 183). Claim 1 has the following features:
1. A method of processing a sulphide mineral, said method comprising the steps of:
2.Milling the sulphide mineral in a vertical stirred mill
3.To P80 in the range from 2 to 30 micron
4.To produce an activated sulphide mineral; and
5. Oxidatively leaching the activated sulphide mineral in oxygen
6. At a temperature less than about 120oC and
7. At an oxygen pressure less than about 1000kPa
8. For a time in the range of from, 15 to 150 minutes,
9. Such that elemental sulphur is the predominant sulphur product formed.
Based on a reading of the specification as a whole, I consider that all the above features are essential to the working of the invention. WMCL had raised 14 citations against the ground of novelty in the statement of grounds and particulars. At the hearing WMCL stated that it would rely on three of those documents to show lack of novelty. The three documents were referred to as the Corrans and Angove paper, the Pawlek paper and the Vezina paper.
The Corrans and Angove Paper (Minerals Engineering, Vol 4, Nos 7-11, pp 763 to 776, 1991. "Ultra Fine Milling for the Recovery of Refractory Gold", I J Corrans and J E Angove)
In regard to the Corrans and Angove paper an issue arose as to whether this paper constituted a publication by a learned society. The opponent stated that:
· This paper had been read out at a Minerals Engineering conference in Singapore on 20 February 1991.
· The paper was published in Minerals Engineering Vol 4 Nos 7-11, 1991, being available in Australia on or shortly after 4 July 1991.
The opponent made reference to the relevant law as follows:
Section 24 Validity not affected by certain publication or use
(1) For the purpose of deciding whether an invention is novel or involves an inventive step, the person making the decision must disregard:
(a) any information made publicly available, through any publication or use of the invention in the prescribed circumstances, by or with the consent of the nominated person or patentee, or the predecessor in title of the nominated person or patentee; and…
but only if a patent application for the invention is made within the prescribed period.
Regulation 2.2 Publication or use: prescribed circumstances and periods
(2) For the purposes of paragraph 24 (1) (a) of the Act ("validity not affected by certain publication or use"), the following circumstances are prescribed:
…
(c) the publication of the invention in a paper written by the inventor and:(i) read before a learned society; or
(ii) published with the inventor's consent by or on behalf of a learned society; or…
Regulation 2.3 Prescribed period: publication or use affecting validity
(1) For the purposes of subsection 24 (1) of the Act ("validity not affected by certain publication or use"), in the case of information of the kind referred to in paragraph 24 (1) (a) of the Act, the prescribed period is:
…(b) in the case of the circumstance mentioned in paragraph 2.2 (2) (c):
(i) if the application claims priority from a basic application made within 6 months of the date of the first reading or publication referred to in the paragraph - 12 months from the making of the basic application; and
(ii) in any other case - 6 months after the first reading or publication; and…
The opponent then made the following submissions:
· The preconditions of s7(1) have been established as the paper was published at the latest on or shortly after 4 July 1991 - this is about 15 months before lodgement of the complete specification and 11 months before the second provisional.
· The applicant has answered the grounds in relation to this publication in two ways:
1. By proving that the paper itself was not published (although it was read) at the Minerals Engineering conference in Singapore on 20 February 1991. If this were not the case, s24(1)(a) would not save the application because the application was not made within the prescribed period of 6 months after the day on which the paper was presented: Reg 2.3(1)(b). The opponent cannot presently challenge this evidence. Accordingly, the question whether the paper was "read before a learned society" in terms of Reg 2.2(2)(c)(i) does not arise.
2. The applicant must also prove:
(a) that the publication in Australia of the paper was "by or on behalf of a learned society" in terms of Reg 2.2(2)(c)(ii); and
(b) that, in terms of s24(1), "a patent application for the invention [was] made within the prescribed period" of 6 months after the first publication, in July 1991. This means the Applicant must show that provisional application no PK9121 is "a patent application for the invention".
· In respect of item 2(a):
q The Minerals Engineering conference in Singapore does not come within the concept of "learned society". The conference was organised by the Camborne School of Mines. Its participants were an ad hoc group - "a wide range of people, for example from academia, research institutes, industry and consultancy", who had responded to "notices placed in international journals and the like". This is not a society of any kind, however learned were the individual attendees.
q Accordingly, the publication in Minerals Engineering Vol 4 Nos 7-11, 1991 was not on behalf of a learned society. It plainly was not by a learned society, as its publisher was Pergamon Press plc.
· In respect of item 2(b):
q The Patent Examiners Manual, Vol 2 at 3.4.6.1.2 indicates that the term patent application includes a provisional application, but the invention now claimed must be fairly based on the matter disclosed in the provisional.
q The applicant has no made no attempt to discharge the onus of proving that provisional application PK9121 is properly an application for "the invention" - that is, the invention now claimed and said to be not novel.
q There is not a real and reasonably clear disclosure of a number of matters in the provisional specification, particularly in relation to the integers of:
Ø vertical stirred mill
Ø p80 of 2-30 microns
Ø production of an activated sulphide mineral
The applicant made the following submissions in response:
· Declarant Wills states that the Corrans and Angove paper was presented at a conference on 20 February 1991 and was read with the aid of overhead slides and without any written material being disseminated.
· The Camborne School of Mines had responsibility for the organisation and running of the above mentioned conference.
· The proceedings of the conference were published in a special issue of Minerals Engineering which was subsequently publicly available in Australia in July 1991.
· If we assume the Minerals Engineering conference constitutes the proceedings of a learned society then the requirement of filing an application within six months of the matter being published has been met. The provisional application was filed on 25 October 1991, clearly within six months of July 1991.
· Mr Wills at paragraph 9 of his declaration states that the Minerals Engineering conference attracts a wide range of people, for example from academia, research institutes, industry and consultancy.
· There is a published record of the proceedings unlike the Ralph Parsons case (infra).
· The opponent has interpreted the term society far too narrowly so as to exclude societies which are not registered. The convenors of the Minerals Engineering conference are seeking to promote innovation and developments in mineral processing and extractive metallurgy and call for interested experts to participate in the conferences, which are held on an annual basis. Exhibit BAW-1 indicates that the aim and scope of the journal of the conference is the informed dissemination of information to interested persons.
· The opponent seeks to graft on the requirement of fair basis of the provisional on the current specification in relation to section 24 and related parts of the regulations.
· Fair Basis cannot be imported into those sections of the act and regulations where there is no clear wording to that effect. Section 24 clearly indicates that one must disregard information published in a certain way. The related regulations 2.3(1)(b)(i) do not require any fair basing.
· In the matter of fair basing all amendments of the specification allowed by the Patent Office would have been tested for fair basis.
Before I proceed to consider the issue of novelty I must determine if the Corrans and Angove paper must be disregarded in respect of section 24(1)(b) read together with regulations 2.2(2)(c) and 2.3(1)(b). For this purpose I have to determine if the publication of the paper was "by or on behalf of a learned society" in terms of Reg 2.2(2)(c)(ii). Hence, I have to determine if the Minerals Engineering conference, or the convenors thereof, did or did not constitute a learned society. Both the opponent and applicant referred to the teaching in Ralph M Parsons Co (Beavon's) Application [1978] FSR 226 with regard to the term "learned society". The opponent was of the opinion that the forum at which the paper was read was not that of a properly constituted society however learned the participants might have been. Ralph Parsons case (supra) states the following about learned societies:
· Any properly constituted society made up of persons seeking to promote and organise the study of specific subjects by the provision of a forum for discussion and a means of contact for those of a common interest.
· Historically at least learned societies were not associated with commercial exploitation, purporting to disseminate the relevant learning without consideration of economic gain
· (It is) usual for societies aspiring to the epithet "learned society" to publish records of their proceedings and indeed this is to be expected since such societies are presumed to be concerned not with arcane knowledge but with the dissemination of information amongst the members of the society whether they are able to attend meetings or not.
Based on the evidence from both sides the following facts emerge:
· The Corrans and Angove paper was read out at the Minerals Engineering '91 Conference (held between 20-22 February 1991) at the Marina Mandarin Hotel in Singapore on 20 February 1991.
· The proceedings of the conference was published in the journal Minerals Engineering Vol 4, Nos 7-11, 1991 entitled Special Issue Minerals Engineering '91 by Pergamon Press.
· The Editor-in-Chief of Minerals Engineering is identified as Barry A Wills of the Camborne School of Mines, Cornwall UK.
· The Minerals Engineering journal states that it is "An international journal devoted to innovation and developments in mineral processing and extractive metallurgy" and that "The purpose of the Journal is to provide for the rapid publication of topical papers featuring practical developments in the allied fields of mineral processing and extractive metallurgy."
I have to determine if the Minerals Engineering Conference (MEC) did or did not constitute a learned society. Declarant Wills states:
"The ME conferences are promoted to potential delegates internationally through notices placed in appropriate industry journals and the like…"
"…and the conferences attract a wide range of people, for example from academia, research institutes, industry and consultancy".
"…the ME conferences are conducted for the exchange and dissemination of ideas and technical information in mineral processing and extractive metallurgy. Such conferences promote the study of these and related topics and further provide a convenient forum for their discussion."
"I was a senior lecturer at the Camborne School of Mines (CSM) in Cornwall, England during 1991 and up to March 1996. CSM is now part of the University of Exeter."
"CSM had responsibility for the organisation and running of the Minerals Engineering '91 international conference (hereinafter "the conference") held at the Marina Mandarin Hotel, Singapore from 20-22 February 1991. I had primary responsibility at CSM for the organisation and running of the conference."
"The Minerals Engineering conferences are an annual event. CSM was subsequently responsible for the organisation and running of the Minerals Engineering '92 conference in Vancouver and responsibility for subsequent conferences has fallen to CSM Associates Ltd, the consultancy arm of CSM, in collaboration with CSM."
I note that the Camborne School of Mines had responsibility for the organisation and running of the '91 and subsequent conferences. The Macquarie Encyclopedic Dictionary, published by The Macquarie Library Pty Ltd in Australia in 1990, defines the terms "school" and "university" (in the context referred to above) as follows:
1. School: - a department or faculty in a university or similar educational institution.
2. University: - an institution of higher learning, conducting teaching and research at the undergraduate and postgraduate level.
The evidence shows that the Camborne School of Mines was in effect " an institution of higher learning, conducting teaching and research at the undergraduate and postgraduate level". Mr Wills states that he had primary responsibility at CSM for the organisation and running of the conference. There was no evidence of a "society made up of persons seeking to promote and organise the study of specific subjects by the provision of a forum for discussion and a means of contact for those of a common interest" to show that the CSM constituted a learned society. Thus I conclude that the Camborne School of Mines did not constitute a learned society.
There is not much case law relating to learned societies. The Ralph Parsons case (supra) gives a couple of examples of learned societies such as the American Chemical Society and the Canadian Natural Gas Processing Association. In Caterpillar Inc v Kozo Miyake [2000] APO 3 (7 January 2000) the delegate found that the Institute of Electrical and Electronics Engineers (IEEE) constituted a learned society. In that case a paper had been presented at the IEEE/RSJ International Workshop on Intelligent Robots and Systems on 4-6 September 1989 in Japan. The conference had been organised by the IEEE. The delegate in that case concluded, "I consider that the IEEE is a learned society within the meaning of the Act, and the publication of AZ1 (the inventors paper) is therefore protected in respect of both novelty and inventive step. The cases of Work Cover Authority of New South Wales v Bitupave Limited [2000] NSWIRComm 50 (6 April 2000) and David McNicol v Australian Capital Territory Health Authority S.C. No. 945 of 1986 Defamation [1988] ACTSC 55 (23 September 1988)) refer to learned societies. They indicate the following bodies as falling within the category:
Royal Society of Chemists, Combustion Institute, International Association for Fire Safety Science, Research Committee for the Fire Code Reform Centre (Building Code of Australia), Royal Australian College of Surgeons, Australian Orthopaedic Association, Orthopaedic Research Society, Connective Tissue Society of Australia and New Zealand, Australian Society of Orthopaedic Surgeons, Australian Medical Association, etc.
The above bodies are established bodies and none of them give any indications that they were formed merely for the duration of a single conference. I have no evidence/indication before me that a conference of its own accord constitutes a learned society. The attendees at the conference as listed in Exhibit BAW-3 were from academia, research institutes, industry and consultancy relating to mineral processing/engineering and could quite conceivably have formed a learned society. However there is no evidence to show that these persons had organised the conference. Mr Wills quite clearly indicates that he had primary responsibility at CSM for the organisation and running of the conference. The evidence shows that the Minerals Engineering conference was promoted to potential delegates internationally through notices placed in appropriate industry journals and the like by the Camborne School of Mines. Thus, there is no evidence of "a body of persons seeking to promote and organise the study of specific subjects by the provision of a forum for discussion and a means of contact for those of a common interest". Thus I am satisfied that the Minerals Engineering Conference '91 did not constitute a learned society.
In light of the above conclusion the Corrans and Angove paper (the C&A paper) can be considered for the purposes of novelty and inventive step. As the C&A paper did not satisfy the prescribed circumstances of regulation 2.2, relating to section 24, there is no requirement for me to determine if the prescribed period was complied with as per regulation 2.3.
The C&A paper is entitled "Ultra Fine Milling for the Recovery of Refractory Gold" and made the following disclosures:
· The use of a stirred pin mill (vertical stirred mill) for ultra fine milling of sulphide minerals, particularly arsenopyrite and pyrite (pages 763-764, fig. 1).
· Mineral particle sizes to P80 from 2 to 30 micron and also sizes up to 80 micron (Tables 1-2, figs.2-4, pages 765-770).
· Oxidative leaching of the sulphide mineral in oxygen at a temperature below 120oC and at an oxygen pressure of 1000kPa or less for about half an hour (pages 769-771).
The applicant submitted that all the essential features of process claimed had not been disclosed, in particular:
1. "Activation" of sulphide minerals. The extraction rates achieved are not attributed to the "activation" of the various minerals.
2. The paper explains the outcomes in terms of changes in the nature of the chemical reactions (see the reference on page 771 to "the shift in the nature of the chemical reactions"). It does not attribute the outcomes to the fact that they produced "activated" sulphide minerals.
3. The prior art makes clear that merely reducing particle size will not inevitably produce an "activated sulphide mineral". The paper by Beckstead et al (Ex. DMM-3) shows that the enhanced reaction kinetics the authors achieved were referable to the fine grinding of the concentrate (from 0.5 microns upwards, preferred range of 12-47) and not to the phenomenon of "activation".
4. Mr Elvish had indicated that the paper disclosed that the milled concentrates were chemically very reactive as a result of the maximisation of the surface area of the product. He states that "However, "activation" is defined in the application at paragraph 3 of page 5 as not being fully understood by requiring a number of factors, five of which are listed and only one of which is surface area."
I shall now deal with the feature relating to activation of the ground sulphide mineral particles. The opposed application refers to the activation by grinding using vertical stirred mills or other types of comminution apparatus. The description at page 5, line 1 onwards, states:
"The preferred type of milling of the sulphide minerals is generally referred to as fine or ultra fine milling and produces a product in which the sulphides are activated, and which subsequently react far more readily with oxidants such as oxygen. The activation of the sulphide minerals is not fully understood, although it is expected to be a result of a number of factors,…"
Apart from the step of ultra fine milling no other step or variation in the milling process is disclosed whereby activation of the particles may be achieved. For instance, there is no indication of desirable grind times, starting sizes prior to grinding, etc. I conclude that if ultra fine milling is carried out in a vertical stirred mill to the specified particle sizes than the minerals are in effect activated.
I shall now compare the features of claim 1 with the disclosure of the citation. I consider that features 1 to 8 have clearly been disclosed in the C&A paper. In the matter of feature 9 (formation of elemental sulphur as the predominant sulphur product formed) I shall initially consider the disclosures of the C&A paper. At page 770 it states:
"In addition, at lower temperatures (ie below 180oC) the formation of elemental sulphur is promoted. In the temperature range above the melting point of sulphur (approximately 120oC), gold surfaces can become passivated by a film of sulphur which retards subsequent dissolution of gold in cyanide solution.
Our work at Ammtec has shown that sulphur passivation is generally not a problem if the temperature is below its melting point."
Further, page 771 makes the following disclosures:
analysis of the low pressure/temperature oxidation products…has shown that these are largely non- or poorly crystalline in nature consisting of elemental sulphur and iron sulphates.
The dominance of a chemical reaction (for leaching oxidation of arsenopyrites) at the lower temperature of 65oC, wherein the elemental sulphur produced will form an "ash" layer around the particles and the rate controlling step will become diffusion through this layer.
Thus reduction in the particle size by UFM will have a substantial effect on minimising the time for complete conversion under conditions of elemental sulphur formation.
For the oxidation of pyrite, a similar situation exists where sulphur formation predominates at lower temperatures.
Based on the above I am satisfied that feature 9 of claim 1 has been disclosed. Thus all the essential features of claim 1 of the opposed application have been disclosed in combination. I consider that claim 1 of the opposed application lacks novelty in light of the C&A paper.
I shall now consider the appended claims. Claim 2 refers to wet milling. The C&A paper at page 764 states, "Slurries of very fine particles have high viscosities which can cause choking in tumbling mills and an enhanced tendency for the charge to centrifuge." And at page 769 it states "The reactivity of sulphide slurries produced after UFM…". There is clear disclosure of wet milling in that the term slurry indicates the presence of a liquid and the paper discusses the milling of slurries in different types of mills. Therefore claim 2 also lacks novelty.
Claims 3 and 4 give particle size ranges of 2 to 20 micron and 2 to 15 micron. The C&A paper has disclosed a wide range of particle sizes which satisfy the requirements of claim 1 and would thus include the ranges of claims 3 and 4. Claims 3 and 4 lack novelty.
Claim 5 defines a temperature range of 80oC to 120oC for the oxidative leach. The C&A paper had disclosed a temperature of 65oC and also indicated that temperatures below the melting point of sulphur (120oC) are suitable for the process. Thus claim 5 lacks novelty.
Claim 6 defines an oxygen pressure in the range of 200 to 1000kPa for leaching. The C&A paper shows pressures of 1000kPa and below (900kPa, for instance) which fall within the range specified. Claim 6 lacks novelty.
Claim 7 defines an oxidative leach time from 30 to 120 minutes. The citation has a leach time of 30 minutes, which is in the range. Claim 7 lacks novelty.
Claim 8 is an omnibus claim defining the embodiments of the examples; but as it is appended to claim 1, it is limited to the features of claim 1 as they are embodied in the examples. The examples disclose temperatures below 100oC and 120oC, particle sizes below 15 micron, and oxygen pressures below 1000kPa. These figures fall within the disclosures of the citation. Thus claim 8 also lacks novelty.
Thus the invention as defined in claims 1 to 8 of the opposed application lacks novelty in light of the Corrans & Angove Paper.
I shall now proceed to assess the other citations for the purposes of Novelty considerations.
The Pawlek Paper (International Symposium on Copper Extraction & Refining, American Institute of Mining Metallurgical and Petroleum Engineers Inc, Baltimore, 1976. Chapter 35, The Influence of Grain Size and Mineralogical Composition on the Leachability of Copper Concentrates, F E Pawlek))
The features disclosed by the paper (in brief) are:
· Comminution of copper concentrates in an attritor within a very short time to a particle size of 1 - 0.1mm (starting from mineral initially ground to particle size of -325 mesh (44 micron)).
· Addition of sodium hydroxide enhances comminution.
· The concentrates, suspended only in water, can be completely dissolved under oxygen overpressure and temperatures ranging from 120-180oC, because the surface area of the concentrate has been significantly increased by the ultra fine grinding.
· Addition of a small amount of silver ions to leach liquor containing sulphuric acid acted as a catalyst for the dissolution of chalcopyrite, because of the formation of local elements on the surface. The addition of Cl- ions was also catalytically very effective.
· With this method it is possible to completely dissolve the copper contained in chalcopyrite concentrates after ultra fine grinding within 30 min at 110oC under an oxygen partial pressure of 1 atm (14 psig). The opponent indicates that 14 psig equates to 101.3 kPa.
On comparing the disclosures of the Pawlek paper with claim 1 of the opposed application, I find a number of differences. I shall deal with these on an individual basis:
1. The opposed application clearly specifies a particle size distribution of P80 in the range from 2 to 30 micron (both parties agreed that this means that 80% by weight of the particles being processed possess a size in the range 2 to 30 micron). This feature has not been disclosed in the paper. Only one of the opponent's declarants, Weller states:
· The size range of particles (in the Pawlek paper) exceeds 1 micron in view of the inherent deficiencies in measuring particle sizes by taking sections and viewing through an electron microscope.
· He was a party to batch grinding using a variety of vertical stirred mills. The results showed that it was very difficult to grind sulphide minerals to a P80 finer than 4 microns after about 1 hour of batch grinding using a vertical stirred mill and grinding media similar to the one used in the Corrans and Angove paper.
· The attritor of the Pawlek paper would behave in a similar manner to the mills used in the above-mentioned trial.
· The ground mineral in the Pawlek paper could thus have particle sizes exceeding 4 micron.
I have to determine if the Pawlek paper has disclosed grinding of mineral particles to size distribution of P80 in the range 2 to 30 microns. The issue is one of disclosure of a particular feature to a skilled addressee and I do not find that the feature of particle size between 2 to 30 microns has been disclosed in the paper. I also cannot conclude from the evidence before me that the skilled addressee would include particle sizes of 1 micron and less in a size range of 2 to 30 micron.
2. The opponent contended that an attritor fell within the ambit of a vertical stirred mill. Fig. 3 of the Pawlek paper shows a drawing of an attritor. This is of similar construction to the vertical stirred mill of the Corrans and Angove paper except that it has a recirculation pipe. Claim 1 of the opposed application refers to a vertical stirred mill. The description of the opposed application at page 5 indicates that fine or ultra fine milling is preferred and that besides a vertical stirred mill (which is preferred) other types of comminution apparatus may also be used to provide the fine or ultra fine milling of the invention. There is nothing in the specification or any evidence by the opponent/applicant (e.g. published literature, textbooks, etc.) to indicate that the recirculation pipe of the attritor in any ways alters its functioning when compared with the vertical stirred mills. I consider that the attritor shown in the citation does fall within the ambit of the term "vertical stirred mill".
3. An issue arose over the meaning of the term 'activated'. The opponent contended that if fine or ultra fine milling was carried out to the recommended particle sizes then such particles were activated. Wadley on behalf of the applicant stated that there was evidence to show that certain kinds of milling did result in activation of the mineral species being milled. The evidence (a paper by Gerlach attached as DMM1 to Mr Muir's declaration) shows activation of chalcopyrite (complex copper sulphide ores) if the ores are "first activated by grinding in a particular manner". The evidence also states that "particularly suitable for the activation are oscillating mills, also called vibration mills". The grind time disclosed in the paper is about 3 hours.
The opposed application states at page 5, that:
"The preferred type of milling of the sulphide minerals is generally referred to as fine or ultra fine milling and produces a product in which the sulphides are activated, and which subsequently react far more readily with oxidants such as oxygen."
The Gerlach paper indicates that it is possible to determine if the ground mineral has been activated. However the paper also indicated that grinding beyond/below a certain time could result in particles that were not activated. I consider that fine or ultra fine grinding in a vertical stirred mill to the sizes defined in the specification will result in activated mineral particles. The Pawlek paper does not disclose a fine/ultra fine grind to the claimed particle size distribution in a vertical stirred mill.
4. The Pawlek paper refers to:
· addition of sodium hydroxide to enhance comminution.
· addition of silver and chloride ions as catalyst to the leach liquor.
This is not a requirement of claim 1 of the opposed application.
Having considered the disclosures of the Pawlek paper with the essential features of claim 1 of the opposed application I conclude that the Pawlek paper has not disclosed each and every one of the essential integers of claim 1. Thus the Pawlek paper does not render claim 1 as lacking novelty. Consequently claims 2 to 8 are also novel when compared with the Pawlek paper.
The Vezina Paper (reprinted from the Canadian Mining and Metallurgical Bulletin, CIM Transactions, Vol LXXVI, pp 89 to 92, 1973. Further Studies on Acid Pressure Leaching a Chalcopyrite-Pentlandite-Pyrrhotite Concentrate, J A Vezina)
This paper makes the following disclosures:
· particle size distribution from above 37 microns to below 10 microns ground in a jar mill.
· leach conditions with temperature of 110oC, oxygen pressure of 80 psig (about 552 kPa) and a leach retention time of 8 hours.
· elemental sulphur constitutes 53.8% of the leach residue (see Table 6 at page 3)
There are a number of differences between the disclosure of the paper and claim 1 of the opposed application. These are:
1. There is no disclosure of milling the sulphide mineral in a vertical stirred mill. Use of a jar mill (a kind of ball mill) is specified. The opponent was of the view that the jar mill fell within the requirement of "other types of comminution apparatus" referred to in the opposed specification for the purpose of producing fine or ultra fine milling. Claim 1 however, clearly specifies the use of a vertical stirred mill and this feature is not disclosed in the Vezina paper.
2. There is no requirement for fine or ultra fine milling to produce an activated mineral species. The opponent submitted that in view of the features of:
·the enhanced chemical response,
·the same extent of dissolution (compared to the prior art) at shorter reaction times and lower oxygen pressures,
disclosed in the Vezina paper, the grinding had in effect produced an activated species. The applicant claims that the increased decomposition of chalcopyrite is equated purely with a decrease in particle size. The applicant also states that the copper extraction is not shown to be higher than 90.6% (see Fig 1 which also shows: at P80 of 29 microns percentage of copper extracted is of the order of 65-70%; at P80 of 20 microns copper recovery is less than 85%). This does not compare favourably with the 99% extraction of the opposed application. In view of the evidence before me I cannot conclude that the Vezina paper has disclosed that the grinding of mineral species in a jar mill has produced an activated mineral species as the extraction figures do not compare favourably with the opposed application.
3. The leach retention time of 8 hours of Vezina is far different from the 15 to 150 minutes defined in claim 1 of the opposed specification. The opponent's declarants stated that:
· The 8 hours is presumably to ensure completion of the reaction and that significantly shorter leach times would apply to Vezina.
· Reduction in leach time to around two hours could be expected for Vezina but with the minerals of the specification to suit.
The applicant was of the view that 8 hours had clearly been specified as the leach time. The Vezina paper discloses the following:
· "…a retention time of 8 hours resulted in the almost complete dissolution of the nickel and the cobalt…" (Abstract - page 1, column 1)
· "The pulps were then pressure leached at 230oF (110oC) under oxygen at 80psig (about 552kPa) for 8 hours." (page 2, column 2)
The Vezina paper has clearly referred to a leach time of 8 hours and indicates that it compared itself with the prior art, which had a leach time of 14 hours. The Vezina paper does not disclose a leach retention time of 15 to 150 minutes.
In view of the non-disclosure of a number of essential features of claim 1 of the opposed application I find that claim 1 does not lack novelty in light of the Vezina paper. Consequently, claims 2 to 8 also do not lack novelty in light of the Vezina paper.
Inventive Step
Subsections 7(2) and 7(3) of the Patents Act 1990 indicate that a claimed invention will lack an inventive step if it is obvious to a person skilled in the relevant art in the light of:
(a) common general knowledge in the art; or
(b) common general knowledge considered together with information publicly available in a single document or through doing a single act, provided that the document or act could reasonably be expected to have been ascertained, understood and regarded as relevant to work in the relevant art in the patent area by the person skilled in the art.
Aickin J. set out the following tests for obviousness in Wellcome Foundation Limited v VR Laboratories (Aust) Pty Ltd (1981) 148 CLR 262 at page 270:
"It is as well to bear in mind that the question of obviousness involves asking the question whether the invention would have been obvious to a non-inventive worker in the field, equipped with the common general knowledge in that particular field as at the priority date, without regard to documents in existence but not part of such common general knowledge."
and at page 286:
"The test is whether the hypothetical addressee faced with the same problem would have taken as a matter of routine whatever steps might have led from the prior art to the invention, whether they be the steps of the inventor or not."
Application of these tests would require:
a determination of the non-inventive worker in the field (or the person skilled in the relevant art ) in Australia
a determination of the common general knowledge in Australia at the priority date
The common general knowledge relevant to the question of obviousness was described by Aickin J. in Minnesota Mining & Manufacturing Co v Beiersdorf (Australia) Limited, (1980) 144 CLR 253 at 292 as:
"The notion of common general knowledge itself involves the use of that which is known or used by those in the relevant trade. It forms the background knowledge and experience which is available to all in the trade in considering the making of new products, or the making of improvements in old, and it must be treated as being used by an individual as a general body of knowledge."
The first step to applying the tests set out above for determining inventive step would involve the determination of those declarants who were persons skilled in the art of hydrometallurgy involved in the extraction of metals from minerals via size reduction and leaching/oxidative leaching processes. There are a number of declarants from Australia and overseas. Some of the overseas declarants have worked in the relevant art in Australia prior to the earliest priority date. Some of the declarants are inventors. Taking all these factors into consideration I consider the following persons skilled in the art in Australia and I shall have regard to their declarations for the purpose of determining the common general knowledge (CGK) in Australia at the priority date in question:
Opponent's declarants:
David Michael Muir, John Harmsworth Canterford and Keith Russell Weller.
Applicant's declarants:
Gary Donald Johnson, Lyn Geoffrey Bernard Wadley, Ronald F Blanks and Rodney D Elvish.
I will consider the declarations of Corrans and Angove, (along with those of the above declarants) if necessary, with regard to establishing the general state of the art in Australia at the relevant priority date.
I shall now proceed to establish the state of the common general knowledge (cgk) in Australia at the relevant date. The opponent stated that the following features were disclosed in the specification and priority document as forming part of the cgk:
1. the use of oxidative leaching in mineral processing (p2),
2. that gold is encapsulated within sulphide minerals and needs to be liberated-e.g. by
chemical destruction of the sulphide structure (p3),
3. the disadvantages of high oxygen cost, high pressure and highly aggressive leach
conditions (p3),
4. retention time of two hours (p3),
5. in provisional PK9121, that fine or ultra-fine milling is well established technology
(p8),
6. the form of vertical stirred mills (pp5-6),
7. that milder oxidation conditions will lead to less than complete oxidation - i.e. to
the formation of elemental sulphur (pp7-8),
8. the idea of grinding mineral ores to make them more reactive (i.e. activate them) in
chemical processes was well known.
The applicant in its submissions has generally identified features 1 to 4 as forming part of the cgk in Australia. In regard to features 5 to 8 I shall review the evidence to determine if they formed part of the cgk.
Feature 5 states that fine or ultra fine milling is well-established technology. Feature 8 states that the idea of grinding mineral ores to make them more reactive (i.e. activate them) in chemical processes was well known. The evidence shows:
· Mr Muir cites seven documents which disclose particle sizes ranging from 0.1 micron to 47 micron, temperatures ranging from 20 to 115oC, pressures ranging from about 1 atmosphere to 3500kPa and leach times from about an hour to several hours. Some of the documents refer to grinding of the particles causing activation and some refer to grinding to smaller particle sizes (and specifically not activation) giving better leach results. There is no indication (apart from their availability in libraries) that these documents formed part of the common stock of knowledge of persons skilled in the relevant art in Australia.
· Mr Canterford refers to two papers which discuss activation of minerals by grinding and then concludes "Based on these and other similar publications, I am of the opinion that myself and those skilled in the art would immediately recognise the potential of the specification of mechanical activation by fine or ultra fine grinding to the leaching of chalcopyrite using alternative processing conditions such as those described in the specification." He does not indicate if the papers were part of the cgk in Australia.
· Mr Weller does not indicate if fine/ultra fine milling was part of the cgk at the relevant date.
· Mr Johnson made the following comments:
· The various documents exhibited by the range of declarants are on the whole very obscure references and are not those references that might be considered well known by those working in the hydrometallurgical or comminution arts.
· Fine grinding had, at 25 October 1991, always been seen by practising metallurgists as something to be avoided at all costs. It was seen as expensive and difficult to do and consequently was not seen as a good solution. Evidence of this is provided in that the various documents exhibited by the declarants are of laboratory scale and scope. It is far easier to ultra fine grind in a labscale mill on a high value concentrate then it is to ultra fine grind on a commercial scale with a low value concentrate. As a result, the common response to the practising hydrometallurgist at 25 October 1991 was to look to modifying the conditions of the oxidated leach to achieve high metal extractions.
· Mr Wadley states in his declaration:
· The combination of ultra fine milling using vertical stirred mills with hydrometallurgical processes in acid systems is not practised and was not in my view known in mid 1991. In 1991 very few practitioners had any experience in ultra fine milling, particularly Australia and it is not obvious. The only known ultra fine milling vertical stirred mills known to me were in South Africa and they were subject to secrecy agreements. This application was to ultra fine mill arsenopyrite ore ahead of alkaline cyanide leaching to extract gold, rather than to ultra fine mill sulphides followed by acid oxidative leaching in a sulphate environment to extract base metals, or oxidise sulphides ahead of gold leaching.
· Mr Blanks states in his declaration (in response to the Muir Declaration):
· There is no discussion of an activating fine or ultra fine grind as opposed to a simple size reducing grind. In particular there is no discussion of the use of a vertical stirred mill to achieve the necessary activation.
· Mr Elvish makes the following submissions:
· …at the priority date of the application…ultra fine grinding was a very new area and typically there was little widespread experience in the art of ultra fine grinding. There were only two commercial installations of ultra fine grinding in Australian concentrators at the priority date. It is relatively rare to fine grind below 40 microns in normal mineral processing applications and where such ultra fine grinding is used it is normally only used to regrind a small portion of the product stream or a very high value product.
· Whilst it is generally acknowledged that a smaller particle size will provide a faster leaching rate or faster leaching kinetics, ultra fine grinding is still perceived as a high cost option.
The evidence generally discusses experimental papers and reports on investigations of the effect of particle size and other parameters on leaching. Some documents refer to activation of the particles by grinding and others refer to particle size being responsible for better reaction results. The evidence shows that a smaller particle size was acknowledged as providing faster leaching rates. However there was no clear indication that it was accepted that fine grinding of particles inevitably lead to the activation of the particles which resulted in faster leaching rates. There is nothing to indicate that the skilled addressee would routinely consider the use of ultra fine grinding for oxidative leaching of minerals and that such grinding lead to the activation of the particles. I do not consider that fine/ultra fine milling constituted part of the cgk of the person skilled in the art at the relevant date in Australia.
Feature 6 relates to the form of vertical stirred mills. The opponent has disclosed the use of an attritor claiming that this is a form of a vertical stirred mill. Only one of the documents cited discloses an attritor, which I found was equivalent to a vertical stirred mill. However the evidence put forward by the opponent does not show that the use of a vertical stirred mill for ultra fine grinding of sulphide mineral species formed part of the cgk in Australia.
Feature 7 states "that milder oxidation conditions will lead to less than complete oxidation - i.e. to the formation of elemental sulphur." The opponent has cited some overseas papers on production of elemental sulphur consequential on oxidative leaching but there is no indication that these disclosures were accepted by persons skilled in the art in Australia as part of their common stock of knowledge at the relevant priority date.
In conclusion I note that the opponent has identified features on an individual basis but has omitted the context in which each feature might be considered to form part of the cgk in Australia. For instance, feature 4, which refers to a retention time of two hours, strictly refers to the conditions applied to the prior art Sheritt process identified in the opposed application. I shall therefore consider each feature stated to be part of the cgk in the proper context in which it was established as part of the cgk in the art.
Thus at the relevant priority date the following was known:
1. the use of oxidative leaching in mineral processing,
2. that gold is encapsulated within sulphide minerals and needs to be liberated-e.g. by
chemical destruction of the sulphide structure,
3. the disadvantages of high oxygen cost, high pressure and highly aggressive leach
conditions,
4. retention time of two hours (as disclosed for the Sheritt process),
8. the idea of grinding mineral ores to make them more reactive (but not activate
them) in chemical processes was well known.
The opponent submits:
"…what the applicant has done is to apply a well-known idea to improve a well-known process and has progressively chosen various parameters to give an appearance of narrowing the claims to avoid prior art. To some extent, these integers (the ones chosen by the applicant) are merely the inevitable result of process steps: e.g., activated mineral; elemental sulphur predominates.
In Raychem Corp's Patents [1998] RPC 31, at 41-50, Laddie J criticised this approach as "parameteritis". Merely to add a known, arbitrary, or obviously desirable integer to a known process does not make it inventive. See headnote paragraphs (2)-(5). This approach was followed by R A Melvin in Nippon Steel Corporation v BHP Steel (JLA) Pty Ltd (1999) APO 70.
Accordingly the invention claimed in each claim is obvious."
I shall refer to the teaching of Laddie J in the Raychem case (supra) at page 40:
"The court is trying to determine in a common sense way how the average skilled but non-inventive technician would have reacted to the pleaded prior art if it had been put before him in his work place or laboratory. The common general knowledge is the technical background of the notional man in the art against which the prior art must be considered. This is not limited to material he has memorised and has at the front of his mind. In (sic) includes all that material in the field he is working in which he knows exists, which he would refer to as a matter of course if he cannot remember it and which he understands is generally regarded as sufficiently reliable to use as a foundation for further work or to help understand the pleaded prior art. This does not mean that everything on the shelf which is capable of being referred to without difficulty is common general knowledge nor does it mean that every word in a common textbook is either. In the case of standard textbooks, it is likely that all or most of the main text will be common general knowledge. In many cases common general knowledge will include or be reflected in readily available trade literature which a man in the art would be expected to have at his elbow and regard as basic reliable information."
Application of this teaching to the present case shows that the opponent has not clearly established any of the documents they have cited as forming part of the cgk in Australia at the relevant date. The opponent has established certain general observations on oxidative leaching as forming part of the cgk. The opponent has also selected bits and pieces from prior art documentation and attempted to show that the claimed invention could easily be arrived at by a combination of these features. However the opponent has not shown that the combination of features (of the invention) as defined in claim 1, would be arrived at as a matter of routine by the skilled addressee possessed of the cgk available at the priority date. For instance the opponent has referred to:
"integers (the ones chosen by the applicant) are merely the inevitable result of process steps: e.g., activated mineral; elemental sulphur predominates."
Though it is possible that activation may arise as a result of fine/ultra fine grinding without carrying out any extra step apart from grinding, it is the combination of all features including leach times that should be disclosed on application of the test for inventive step. Another aspect of the cgk was:
"the disadvantages of high oxygen cost, high pressure and highly aggressive leach
conditions."
Again the opponent has raised this feature in isolation from all other features which the skilled addressee considers before selecting a particular process. Even though this feature might seem disadvantageous, in light of other high costs such as grinding times and related energy consumption, the skilled addressee would need to decide which is an acceptable high cost in view of the end result they seek (see paragraph 87 of Johnson). Some of the declarants have stated that very high metal recovery is not necessarily the most important objective in a leaching process.
Each document is treated in isolation for consideration of inventive step unless there is some indication that the document must be read in combination with another. I do not consider that the opponent has shown that the claimed invention constitutes the application of a well-known idea to a well-known process. The opponent has not established that the narrowing of the claims is merely an exercise in defining meaningless parameters to try and avoid the prior art.
The opponent also sought to show lack of inventive step based on sub-sections 7(2) and 7(3) of the Patents Act 1990. I shall now consider the documents raised by the opponent to determine if they could reasonably be expected to have been ascertained, understood and regarded as relevant to work in the relevant art in the patent area by the person skilled in the art. The documents raised were those raised for the purposes of lack of novelty.
I shall deal with the Corrans & Angove, Pawlek and Vezina papers. In the matter of whether "the documents could reasonably be expected to have been ascertained", I have to determine if the documents would have turned up in a search of patent and non-patent literature in the relevant art. The papers were published in mining/metallurgical journals (shown to be available to the general public in Australia before the earliest priority date) and as such I expect that these would be located as part of a literature search. Given the contents of the papers I am satisfied that the papers would be understood and regarded as relevant to the problem identified in the opposed application. The aim of the opposed invention stated:
"…to avoid, or at least partly alleviate, the difficulties and expenses referred to above with traditional processing methods of oxidative hydrometallurgy, and in particular with the oxidative leaching of a mineral species."
The difficulties and expenses related to:
· Oxidative leaching processes usually require severe physico-chemical conditions in order to achieve acceptable rates of oxidation and/or final recoveries of metal,
· Severe physico-chemical conditions often mean temperatures in excess of 200oC and total pressures in excess of 2000kPa,
· Use of large quantities of oxygen, both on stoichiometric considerations and in practice where amounts in excess of stoichiometric requirements are used,
· Costly high maintenance equipment and sophisticated technology.
The Corrans & Angove Paper
I have discussed the disclosures of this paper under lack of novelty. This paper discloses all the essential features of the invention claimed in the opposed application. Given the problems of the prior art, this paper would lead the skilled addressee in the direction of the claimed invention, as it discloses lower leach temperatures, lower oxygen pressures, ultra fine grinding, reduced leach times, lower oxygen consumption and higher recoveries of metal. I conclude that the invention as claimed in claims 1 to 8 of the opposed application lacks an inventive step in light of the Corrans & Angove Paper.
The Pawlek Paper
In brief, the paper discloses the following:
· Comminution of copper concentrates in an attritor within a very short time to a particle size of 1 - 0.1mm
· Addition of sodium hydroxide enhances comminution.
· The concentrates, suspended only in water, can be completely dissolved under oxygen overpressure and temperatures ranging from 120-180oC, because the surface area of the concentrate has been significantly increased by the ultra fine grinding.
· Addition of a small amount of silver ions to leach liquor containing sulphuric acid acted as a catalyst for the dissolution of chalcopyrite, because of the formation of local elements on the surface. The addition of Cl- ions was also catalytically very effective.
· With this method it is possible to completely dissolve the copper contained in chalcopyrite concentrates after ultra fine grinding within 30 min at 110oC under an oxygen partial pressure of 1 atm (14 psig). The opponent indicates that 14 psig equates to 101.3 kPa.
I have to determine "whether the hypothetical addressee faced with the same problem would have taken as a matter of routine whatever steps might have led from the prior art to the invention, whether they be the steps of the inventor or not."
The disclosure shows oxidative leach conditions which are not severe (pressures below 1000 kPa and temperatures below 200oC). The particle size is between 1 to 0.1 micron. I have to determine if the skilled addressee would (as a matter of routine):
· Increase particle size to P80 in the range 2 to 30 micron
· Reduce leach temperatures to below 120oC
· Avoid addition of silver and chloride ions to leach liquor as a catalyst
· Avoid addition of sodium hydroxide to the particle grinding step
The document does not indicate huge power consumption on grinding, nor any reason that it ought to consider larger particle sizes. Larger particle sizes were leached but no firm conclusion on the usefulness if any was shown. There is no indication of any huge oxygen consumption or high oxygen pressures. The document discloses use of lower temperatures of 110oC (in conjunction with the addition of silver and sulphate ions) and the production of elemental sulphur as a predominant sulphur product. There is nothing to show that the skilled addressee would be moved in the direction of the invention given that the Pawlek paper process does not suffer from most of the prior art deficiencies.
The Vezina Paper
The paper discloses:
· particle size distribution from above 37 microns to below 10 microns ground in a jar mill.
· leach conditions with temperature of 110oC, oxygen pressure of 80 psig (about 552 kPa) and a leach retention time of 8 hours.
· elemental sulphur constitutes 53.8% of the leach residue (see Table 6 at page 3)
I have to determine "whether the hypothetical addressee faced with the same problem would have taken as a matter of routine whatever steps might have led from the prior art to the invention, whether they be the steps of the inventor or not."
The disclosure shows oxidative leach conditions which are not severe (pressures of about 550 kPa and temperatures of 110oC). The particle size is between above 37 micron to below 10 micron. I have to determine if the skilled addressee would (as a matter of routine):
· discard the jar mill in favour of a vertical stirred mill
· reduce the leach retention time from 8 hours to 15 to 150 minutes
The process of the Vezina paper does not suffer from the defects of the prior art listed in the opposed application and consequently it does not face the problem defined therein. The Vezina study shows a reduction of leach time from 14 to 8 hours. The leach time of 8 hours appears long in face of the prior art Sheritt process identified in the opposed application. However the Sheritt process uses a high temperature/high pressure, heavy oxygen consumption process. Thus there is nothing to indicate that the skilled addressee would prefer to move towards higher pressures and temperatures to shorten leach times. The particle size was reduced from the 44 micron (325 mesh) previously used to 20 micron (see Summary of paper) for the study. The particle size is already in the fine range and there is no incentive for the skilled addressee to grind even finer. Thus the opponent has not established that in light of the Vezina disclosure and established cgk the skilled addressee would arrive at the invention when faced with the problems of the prior art.
I have found that the opposed invention lacks an inventive step in light of the Corrans & Angove paper. I do not consider that the invention of the opposed application lacks an inventive step in light of the Pawlek or Vezina papers.
Manner of Manufacture
The opponent submitted:
"The present alleged invention is merely the mere new use of a known process (fine or ultra-fine milling) for which its known properties make it suitable. See Commissioner of Patents v Microcell Limited (1959) 102 CLR 232."
The applicant was of the view that Section 6 was not applicable and in any case had been considered under Obviousness/Lack of Inventive Step.
I have compared the claimed invention with the prior art documents of Pawlek and Vezina. In both cases there were differences between the citations and the claimed invention. Neither document disclosed the combination of features of the opposed invention. The issue is not one of merely the use of fine/ultra fine milling, as there were differences in particle sizes, temperatures and leach times. I do not find that the claimed invention is merely for the new use of a known process. I have indicated that the Corrans & Angove Paper disclosed the claimed invention. However the Paper makes it clear that it is the combination of ultra fine milling with low pressure, low temperature leaching that gives the best results in terms of metal recovery. Consequently the opponent has not established that the opposed invention is not a manner of manufacture.
Section 40/Fair Basis
The opponent stated:
"If, contrary to the above submissions, Corrans and Angove does not anticipate (except by reason of s24(1)) and Pawlek and Vezina each does not anticipate the present invention, …this can only be if a strict construction is adopted of the following terms, rather than a purposive one. If so, the integers which include those terms are not fairly based on the specification in terms of s40. The terms are:
1. milling … in a vertical stirred mill,
2. to a p80 in the range from 2 to 30 microns,
3. to produce an activated Sulphide mineral;
4. at a temperature less than about 120oC,
5. oxygen pressure less than about 1000kPa,
6. oxygen pressure of between about 200kPa and 1000kPa,
7. such that elemental sulphur is the predominant sulphur product formed.
In respect of the vertical stirred mill, it was stated that an attritor fell within this category. I had found that there was sufficient evidence to show that this was indeed the case. The description at page 5, second paragraph, clearly identifies a vertical stirred mill as a preferred apparatus. Hence the definition of the same in claim 1 as an essential feature has a clear disclosure on which it is fairly based (see CCOM Pty Ltd v Jeijing Pty Ltd, 28 IPR 481, "real and reasonably clear disclosure of its subject matter in the specification").
Looking at particle sizes, I note that the feature has set out a definite range. I have considered the evidence in this regard and did not find that particle sizes of 0.1 to 1 micron fell within the range of 2 to 30 microns. The description at page 6, first paragraph discloses, "…a ground product size of P80 of 30 microns or less is preferred, with particular benefits being found with a P80 between 2 to 15 microns." Claim 1 has not claimed particle sizes not disclosed in the description.
The opponent claimed activation of the mineral if a fine or ultra fine grind was carried out as matter of routine. The opponent has not shown (and/or produced evidence to show), for the citations raised, that the grinding of particles as per the prior art sizes and mills would produce activated mineral particles. The opposed description at page 5, first paragraph, refers to activation of the mineral by fine grinding and the factors which possibly contribute to activation. It further states that "A preferred type of apparatus which may be suitable for producing fine or ultra fine sulphides in an activated form is a vertical stirred mill". The feature of activation is thus based on a real and reasonably clear disclosure in the description.
In the matter of temperatures and pressures the description as a whole including the examples give a clear disclosure of the temperature and pressure ranges claimed in the claims. For instance, Example 4 at page 11 discloses, "The milled pulp was oxidatively leached at a temperature below 120oC and an oxygen overpressure below 1000kPa." Thus there is a clear disclosure of the claimed pressures and temperatures in the opposed description.
The description at pages 7 to 10 (showing the chemical reactions which predominate and produce elemental sulphur) provide a firm basis for the feature of "elemental sulphur is the predominant sulphur product formed" claimed in claim 1.
I do not find that a strict construction approach was adopted for the purpose of assessing novelty and inventive step considerations against the Pawlek and Vezina papers.
SUMMARY
The opponent had raised grounds of novelty, inventive step, manner of manufacture and fair basis. The grounds of lack of novelty and inventive step have been established for all claims in light of the Corrans and Angove paper. The grounds of manner of manufacture and lack of fair basis have not been established.
The opposition succeeds. In my view there is no patentable subject matter in the specification and I therefore refuse this application. Unless the Commissioner is served with a notice of appeal within 28 days of the date of this decision, I direct the application be refused.
COSTS
Both parties initially stated that costs should follow the event. They then modified their submissions to state they wished to review the decision before putting in submissions on costs. Accordingly I direct that the applicant and the opponent file their submissions on costs, with the Office, within two weeks of the date of issue of this decision.
Jacob Elijah
Delegate of the Commissioner of Patents
Patent attorneys for the applicant : Wray & Associates, Perth
Patent attorneys for the opponent : Griffith Hack, Sydney
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