T 0992/06 (Anti-microbial compositions/UNILEVER PLC.) 19-06-2009

Reasons for the Decision

1. The appeal is admissible.

Main request

2. Inventive step

2.1 Closest prior art

2.1.1 The closest prior art for assessing inventive step is normally a prior art document disclosing subject-matter conceived for the same purpose or aimed at the same objective as the claimed invention and having the most relevant technical features in common with it, i.e. requiring the minimum of structural modifications.

2.1.2 Document (7) discloses antimicrobial compositions having also deodorant properties (see "Synopsis", last paragraph). These compositions contain an antimicrobial agent (e.g. Triclosan, Ciba Geigy) (see page 85, "Résumé") and ethanol. Keeping in mind that ethanol contains water, unless otherwise specifically mentioned, that it is anhydrous, water is also present. However, document (7) does not mention the presence of any chelating agent.

2.1.3 Document (1) discloses antibacterial compositions containing an antimicrobial agent such as Triclosan and a chelating agent such as EDTA with an enhanced activity of the said antimicrobial agent, in particular against Pseudomonas spp (see page 1, line 28 to page 2 line 27). This composition can also contain carriers such as deodorant creams or sticks (see page 2, lines 50 to 52) or perfumes (see page 4, line 44) and can also be under the form of an aerosol formulation (see example 8). Furthermore, example 8 of this document (see page 9) mentions, in addition to the presence of ethanol and thus water (see paragraph above), the presence of EDTA, which is a chelating agent, Dichlorophen or 4,4'-dichloro-2,2'-methylenediphenol, which is a polyhydric alcohol and a propellant.

In view thereof, document (1) is the closest prior art, since it differs from the claimed subject-matter only in that the chelating agent EDTA has a constant of 10**(25.1)whereas the chelating agents of the present invention have a constant of 10**(26) or greater. Document (7), which does not disclose any chelating agent at all, is thus less relevant than document (1).

2.2 Technical problem to be solved

2.2.1 Thus, for defining the objective technical problem to be solved in view of document (1), the technical results or effects successfully achieved by the claimed subject-matter need to be determined.

2.2.2 Figure 2 on page 132 of document (14) shows the link between the iron-stability constant of some transition-metal chelators and the inhibition of in vitro bacterial-growth-inhibitory activity. In view of this Figure 2, the respondent inferred that starting from the binding constant of 10**(26), the inhibition is high and that this could not be predicted from the teaching of document (1). Moreover, Figure 4 on the same page of the same document shows a longer deodorant efficacy when DTPA, having a binding constant greater than 10**(26), is used instead of EDTA as a chelator. The respondent concluded that the long-lasting effect of the claimed compositions was shown and was not derivable from the disclosure of document (1) and thus justifies the presence of an inventive step.

2.2.3 The board is not convinced by the respondent's argument for the following reasons:

- Figure 2 of document (14) shows nine plots on the graph and none of them is specifically attributed to a specific chelating agent. Moreover, the text below this graph mentions only four chelating agents, namely CDTA, EDDHA, EDTA and TTHA. Hence, a conclusion concerning a better bacterial-growth-inhibition of TTHA, CDTA or EDDHA compared to EDTA cannot be drawn, since the plots are not attributed to a specific chelating agent. This graph is therefore not conclusive.

- The results displayed in Figure 4 of document (14), although showing the effect of an ethanolic aerosol containing DTPA is greater compared to the same ethanolic aerosol containing EDTA, do not represent the closest approximation of the closest prior art, since in the patent in suit (see table 4 on page 11) DTPA has a binding constant of 10**(28.6)whereas TTHA, which also falls within the requirement set out for the binding constant in claim 1, has a binding constant of 10**(26.8). TTHA should have been used as the closest approximation of EDTA (see T 181/82, OJ EPO 1984, 401, point 5). Therefore, these data do not show convincingly the presence of an improved effect across all of the claimed compositions.

2.2.4 In the absence of any proven advantages provided by the claimed process vis-à-vis the compositions disclosed in document (1), the problem underlying the patent in suit can be seen in the provision of alternative aerosol compositions having anti-bacterial properties.

2.2.5 As a solution, the patent in suit proposes antimicrobial compositions as defined in the set of claims of the granted version.

2.2.6 In view of the examples set out in the patent in suit, the board finds it plausible that the problem has been solved.

2.3 Obviousness of the solution

2.3.1 It is thus necessary to investigate whether the person skilled in the art would consider the claimed solution obvious in the light of the cited prior art.

2.3.2 Example 8 on page 9 of document (1) discloses the following aerosol anti-bacterial composition:

2,4,4**(1)-trichloro-2**(1)-hydroxydiphenyl ether 0.08%

EDTA (di-sodium salt) 0.08% Dichlorophen 0.25%

Perfume 1.25%

Alcohol denaturant 0.01%

Diethylphthalate 1.39%

Propellant 10.00%

Ethanol to 100%

Propellant which may be used include trichloromonofluoromethane, dichlorofluoromethane and dichlorotetrafluoroethane.

The board considers in this respect that ethanol always contains water unless specifically mentioned, that it is anhydrous. Hence water (see feature (iii) (a) of claim 1) is also present in the composition of example 8 of document (1).

According to the description EDTA enhances the activity of the anti-microbial agent, here 2,4,4**(1)-trichloro-2**(1)-hydroxydiphenyl ether or Triclosan.

2.3.3 The only differences between one of the claimed alternative compositions, namely (iii) (a) (see point II above) and the one described in example 8 of document (1) lie in the nature of the chelating agent and its alleged function.

2.3.4 The first question to be examined is whether or not the person skilled in the art reading document (1) would understand that EDTA is only used as an enhancer without any anti-microbial activity per se.

Document (11) explains that EDTA can be used in cosmetic creams and lotions and that either alone, or as a booster in combination with other commonly used preservatives such as the parabens, imidazolidinyl urea and quaternary ammonium compounds, can function as an antimicrobial agent. It is most effective against gram negative organisms such as Pseudomonas aeruginosa and Escherichia coli (see page 18, right-hand column). Furthermore, document (10), which mentions on page 324, third paragraph from the bottom, that EDTA can be used in toiletry and cosmetics formulations, also mentions that EDTA is a chelating agent active against Pseudomonas aeruginosa (see page 331, Table 4).

In view of the above, the person skilled in the art would understand that EDTA in document (1), in particular example 8, acts also as an anti-microbial agent.

2.3.5 It remains to be examined which alternative composition the person skilled in the art, knowing that EDTA also acts as an anti-microbial agent in document (1), would have envisaged in order to solve the technical problem defined above (see point 2.2.4).

Document (10), Table 4 shows the anti-microbial activity against P. aeruginas in decreasing order for four chelating agents, namely CDTA >

EDTA > DTPA > HEEDTA.

Hence, the person skilled in the art seeking to solve the problem as mentioned in point 2.2.4 would have concluded that the replacement of EDTA with CDTA in Example 8 would have resulted in a further aerosol composition.

2.3.6 Hence, the person skilled in the art, seeking to solve the problem as mentioned in point 2.2.4 above, would replace the chelating agent (EDTA) of example 8 of document (1) by the other chelating agent (CDTA) mentioned in document (10) to arrive at one alternative of the claimed invention, namely (i)+(ii)+(iii) (a) (water), without any inventive skill.

2.3.7 The board observes in this respect that the discussion about Dichlorophen is of no relevance, since the conclusion of the board is based on the claimed alternative (i)+(ii)+(iii) (a) (water) and not on the alternative (i)+(ii)+(iii) (c) (polyhydric alcohol or derivative thereof).

2.4 In view thereof, the subject-matter of claim 1 does not involve an inventive step in the sense of Article 56 EPC and since the board can only decide on a request as a whole, the present request is to be rejected.

First auxiliary request

3. Amendments

3.1 Claim 1 contains the feature "(iv) a volatile propellant at from 30 to 99% by weight of the aerosol composition." This amendment finds a basis in the application as originally filed (see page 18, lines 5 to 8). It represents a restriction of the scope of the granted patent.

3.2 There is no objection under Article 123(2),(3) EPC.

4. Inventive step

4.1 The subject-matter of the first auxiliary request differs from that of the main request in that it mentions the range of propellant present in the aerosol (see feature (iv)).

4.2 Document (1) remains the closest prior art, because example 8 of this document also mentions the presence of a propellant, but in an amount of 10% (see point 2.3.2 above).

4.3 Although the respondent argued that the claimed composition performs well with a high efficacy, this allegation has not been substantiated by any comparative data. Therefore, in the absence of any data, the problem underlying the patent in suit is identical to the one mentioned in point 2.2.4 above, that is to say, the provision of alternative aerosol compositions having anti-bacterial properties.

4.4 In view of the examples set out in the patent in suit, the board finds it plausible that the problem has been solved.

4.5 It is thus necessary to investigate whether the person skilled in the art would consider the claimed solution obvious in the light of the cited prior art.

In assessing inventive step of claim 1 of the main request, the board has decided that it would have been obvious for the person skilled in the art to replace in example 8 of document (1) EDTA by CDTA and to arrive thus, without inventive ingenuity, at one of the alternatives of the claimed invention, namely (i)+(ii)+(iii)(a) (water).

Documents (8) and (13) both relate to aerosol compositions containing an anti-bacterial compound. Document (8) discloses an aerosol personal deodorant containing from 24 to 60% of propellant (see Tables 1, 3 and 6). Document (13) also relates to an aerosol composition containing 40% of propellant. In view of these two documents, it appears that the amount of propellant can range up to over 60% without impairing the anti-bacterial properties of the aerosol compositions. Thus, one of the obvious alternatives offered to the person skilled in the art, starting from example 8 of document (1) and seeking to make another aerosol composition having anti-bacterial properties, would have been to replace EDTA with CDTA and to increase the amount of propellant as mentioned in document (8) and/or document (13), that is up to 60%. Such an alternative falls within the claimed invention, namely (i)+(ii)+(iii)(a)+(iv), and it results therefrom that the subject-matter of claim 1 does not involve an inventive step.

4.6 Since the board can only decide on a request as a whole, the first auxiliary request is rejected.

Second and third auxiliary requests

5. Claim 1 of both the second and the third auxiliary requests contains the same alternative as that of Claim 1 of the first auxiliary request, namely (i) + (ii) + (iii)(a) + (iv).

For this alternative, the board has come to the conclusion that it does not involve an inventive step (see point 4.5 above).

For the same reasons, claim 1 of both the second and the third auxiliary requests do not involve an inventive step.

5.1 These requests do not fulfil the requirements of Article 56 EPC.

Fourth auxiliary request

6. Amendments

6.1 The solubility promoter under point (iii) in claim 1 has now been limited to organic amines. Such a limitation to one of the different possible options for a feature does not contravene Article 123(2) EPC, as long as it is directly and unambiguously derivable from the application as originally filed.

6.1.1 In originally filed claim 18, dependent from claim 1 as originally filed, five options were disclosed for the type of solubility promoter to be present in the claimed compositions (see (iii)). An organic amine was clearly mentioned. Therefore, the combination of the features (i) to (iv) now mentioned in claim 1 of the fourth auxiliary request is one of the five originally disclosed combinations. It is thus clearly and unambiguously derivable from the application as originally filed.

6.2 Furthermore, the organic amine (solubility promoter) has been limited to a list of specific amines. This list of specific amines is disclosed in the description as originally filed (see page 15, lines 1 to 7). Hence, this limitation does not amount to the introduction of a new teaching and is thus in agreement with the requirements of Article 123(2) EPC.

Moreover, these amendments amount to a limitation of the claimed scope and are thus allowable under Article 123(3) EPC.

7. Inventive step

7.1 Document (1) remains the closest prior art and its content differs from the subject-matter of claim 1 not only in the nature of the chelating agent used in the claimed compositions but also in the compulsory presence of specific amines or mixtures thereof.

7.2 As already explained in point 2.2.4 above, due to the absence of any relevant comparative experiments, the problem underlying the patent in suit can only be seen in the provision of alternative aerosol compositions having anti-bacterial effects.

7.3 In view of example 2 in Table 2 and examples 4 to 7 in Table 5, the board is satisfied that this problem was solved.

7.4 It must now be assessed whether the person skilled in the art would consider this solution as obvious in view of the prior art.

7.4.1 The board notes that the appellant did not submit any facts and/or arguments against this request. Nor can the board find in the cited prior art a hint leading the person skilled in the art to the claimed subject-matter. Indeed, no mention can be found in example 8 of document (1) or in the whole teaching of this document or in the other cited documents (see point IV above) of the presence of an organic amine in an aerosol composition. The person skilled in the art would not find either in any other documents cited an incentive to add an organic amine to the aerosol compositions described in document (1) to arrive at the claimed aerosol compositions which still retain the anti-bacterial properties.

7.5 Claim 1 thus meets the requirement of Article 56 EPC. The same conclusion applies to claims 2 to 15, which represent particular embodiments of the subject-matter of claim 1.

Each of the claims 16 to 18 (see point VI above) involving a composition according to claim 1 is based on the same inventive concept and derives its patentability on the same basis as does claim 1.

7.6 In conclusion, the amended fourth request before the board complies with the requirements of the EPC.

7.7 Since this request fulfils the requirements of the EPC, it is not necessary for the board to examine the remaining fifth auxiliary request.

8. Article 111(1) EPC - Remittal to the first instance Although the board has come to the conclusion that the amended fourth auxiliary request was to be allowed, it was noted that the description had still to be brought into conformity with the claims of the present request. Therefore, having regard to the fact that the function of the boards of appeal is primarily to give a judicial decision upon the correctness of the earlier decision taken by the first instance, the board exercises its discretion under Article 111(1) EPC to remit the case to the first instance in order for the description to be adapted to the allowable claimed subject-matter according to the amended fourth auxiliary request submitted before the board at the oral proceedings.