T 0378/11 (Detergent compositionwith PAP particles having a specific granulometry/RECKITT) 22-10-2012

1. Priority

In the course of the oral proceedings the Respondent has admitted that the oldest priority (GB0305493) of the patent-in-suit is not valid and that therefore D6 represents state of the art according to Article 54(2) EPC 1973.

2. Admissibility of D19

2.1 D19 was filed less than two months prior to the oral proceedings. Although late filed, Appellant I argued that D19 represented common knowledge because "every scientist is familiar with the effect of particle size on surface area and the effect of surface area on dissolution rate" (Appellant I's letter of 31 August 2012, page 5, last paragraph).

2.2 The Respondent considered this document as being late filed and incomplete, since only two pages of the textbook were submitted.

2.3 Although being late filed, the Board acknowledges Appellant I's argument, that the cited passage on page 179 of D19, referring to the relation of crystal size, surface area and solubility, is common knowledge to a skilled person. The fact that only parts of the textbook have been submitted, does not play a role in the particular case.

2.4 Therefore, D19 is admitted into the proceedings.

Claims according to the main request

3. Article 123(2) EPC

3.1 Paragraph [0035] of the description as granted contains examples of the carrier fluid used for the detergent composition. Among these hydrophobic oils and polyethylene glycol (PEG) are mentioned. In the amended description (main request and auxiliary request) presented by the Respondent the passage referring to PEG has been deleted. According to the Appellants this represents an infringement of the requirement of Article 123(2) EPC, because of a change of the meaning of the term "hydrophobic oils" used in Claim 1.

3.2 The Board cannot follow the Appellants' arguments. Although the term "hydrophobic" does not precisely define which compounds fall within its definition in the grey area between "hydrophilic" and "hydrophobic", it is known to the person skilled in the art that PEG is not "hydrophobic". This is for instance confirmed by D8, page 7, lines 8 and 13, where PEG is referred to as being "water-soluble".

3.3 Thus, the skilled person would read paragraph [0035] of the patent-in-suit as citing hydrophobic oils and PEG as different examples of a suitable carrier fluid. The deletion of PEG from this list of examples does not change the meaning of the term "hydrophobic oils" and does therefore not infringe the requirement of Article 123(2) EPC.

4. Article 84 EPC 1973

4.1 The Appellants objected that expressions like "e.g." and "such as" used in Claim 1 would render the meaning of the claim unclear.

4.2 In the present case the Board cannot share the Appellants' view. The objected passage reading "the detergent composition comprises a carrier fluid selected from hydrophobic oils such as paraffin oil, vegetable oils (e.g. olive oil/sunflower oil) and silicone oil and encapsulated phthalimidoperhexanoic acid (PAP)..." describes that the detergent composition comprises a hydrophobic carrier oil and encapsulated PAP. The various compounds listed are merely examples of the hydrophobic oils; olive oil and sunflower oil are specific examples of vegetable oils. Thus, the wording per se is considered to be clear.

4.3 In addition, in the present case the mention of a limited number of examples representing preferred embodiments of one ingredient of the detergent composition is not considered to infringe the requirement of conciseness either.

4.4 Thus, the requirement of Article 84 EPC 1973 is considered to be met by Claim 1 of the main request.

5. Article 83 EPC 1973

5.1 Claim 1 of the main request refers to "a particle size of from 10-500 mym, more preferably 10-300 mym (e.g. about 250 mym)". According to the Appellants the skilled person does not know what the size refers to, i.e. whether the ranges refer to absolute dimensions or to mean values.

Furthermore, if the latter case were to be assumed, it would not be sufficiently disclosed whether the number average particle size, the weight average particle size or similar parameters were to be used. Given this alleged lack of sufficient disclosure the skilled person was considered not to be in a position to re-work the teaching of the patent-in-suit.

5.2 Although Claim 1 refers to ranges, also a discrete value ("about 250 mym") is cited. Being aware that particles of exactly one specific particle size are practically not feasible on an industrial scale, it can only be concluded that the values disclosed in Claim 1 refer to the average particle size.

5.3 This point of view is supported by the examples on file. Examples 1-4 refer to particle sizes of 200, 250 and 500 mym. Starting from these tests carried out with specific average particle sizes it is concluded that a particle size range between 200 and 500 mym gives best bleaching cleaning results (paragraph [0087]). Tablet Example 1 even refers explicitly to the average particle size of 250 mym and the Comparative Example 1 relates to an average particle size of greater than 750 mym, as distinguished from the corresponding absolute particle sizes ranging between 300-1100 mym.

The conclusion to be drawn from these examples is, that the particle sizes defined in the patent-in-suit refer, unless otherwise indicated, to average particle sizes.

5.4 The Appellants furthermore argued, that even if the Board would come to the conclusion that average particle sizes were meant, no indication as to the kind of average particle size were given (number or weight average particle size). However, no proof has been submitted by the Appellants, that the lack of indication as to the precise kind of average particle size hinders the skilled person from carrying out the present invention.

5.5 Even when considering the Annexes 1 and 2 of Appellant I's letter of 31 August 2012 as an adequate determination of the various mean particle sizes, they only show that these mean values differ. On the contrary, it is also shown that at least some of these values fall within the range presently claimed. Thus, the skilled person could select those kinds of mean values falling within the range 10-500 mym in order to prepare a composition according to the present invention. Whether or not the use of two kinds of mean values leads to different results is a matter of clarity, rather than sufficiency of disclosure. However, the Board has no authority to determine clarity of the feature in question, as this feature was already present in the set of claims as granted.

5.6 Thus, the requirement of Article 83 EPC 1973 is considered to be met.

6. Article 54(1),(2) EPC 1973

6.1 Appellant I objected that compositions according to present Claim 1 would be anticipated by D4. In particular the combination of Claims 1+9+10+12+18+19 was considered to disclose compositions as claimed. Although the feature "encapsulated PAP" was not mentioned in the cited claims, the Appellants argued, that the feature would be met by the enclosure of the composition in a pouch.

6.2 The Board cannot share this opinion. Claim 1 refers to "a package comprising a detergent composition enclosed by a [...] packing material, wherein the detergent composition comprises [...] encapsulated [...] PAP". This means that the encapsulated PAP is enclosed by the packing material. Such a feature has not been disclosed in D4. The passage on page 15, last paragraph of D4 relating to optional coating of the bleaching agent does not necessarily relate to PAP. Thus, no direct and unambiguous disclosure of the cited feature can be found in D4.

6.3 As pointed out by the Respondent, this view has also been supported by the Appellants themselves in their letters of 06 April 2010, page 3, fourth full paragraph and of 26 May 2011, page 3, fourth full paragraph, where both parties stated that encapsulated PAP granules cannot be found in D4.

6.4 Thus, the requirement of novelty is met by the subject-matter of Claim 1 of the main request.

7. Article 56 EPC 1973

7.1 The problem as defined in the present invention was the provision of a detergent composition comprising quickly dissolving PAP particles resulting in improved bleach activity.

The Appellants cited documents D2,D4,D6 and D8 as closest prior art documents.

D2 refers to aqueous liquid bleaching compositions being highly effective for the bleaching of substrates.

The aim of D4 is the provision of a unit dose dishwashing product with improved processing and dissolution characteristics.

The examples 4-6 of D6 illustrate that dishwashing composition with improved bleaching performance may be produced by using coated PAP particles.

D8 teaches about dishwashing compositions achieving excellent cleaning properties and excellent glass appearance without leaving a detergent residue.

Only D2 and D6 explicitly refer to bleaching improvement. D2 reports on PAP particles whose sizes may range between 10 and 1000 mym. Although silicone oils may be present as suds controlling agents, neither specific amounts of hydrophobic oils sufficient to act as carrier fluid, nor a water-soluble or water-dispersible packing, nor the encapsulation of PAP are mentioned.

In contrast thereto D6 reports on coated PAP particles having dimensions ranging between 50-5000 mym, which may be present in a sachet. Thus, given the fact that D6 relates to the same problem and has more features in common with Claim 1 of the patent-in-suit, D6 is regarded to be the closest state of the art.

7.2 The problem of the patent-in-suit vis-à-vis D6 is the provision of a detergent composition with improved bleaching performance.

7.3 The package according to Claim 1 of the main request was proposed as a solution for this problem.

D6 differs from the present Claim 1 in the carrier fluid and the selection of a specific PAP particle size.

7.4 Table 1 of the patent-in-suit highlights that compositions with encapsulated PAP particles with an average diameter in the range of 10-500 mym show an improved bleaching effect compared to a similar composition with PAP particles having an average diameter outside this range. The Appellants have not disputed this effect as such.

The examples and comparative examples of the patent-in-suit differ from the compositions according to Claim 1 of the main request in that the examples do not contain a carrier fluid.

However, the carrier fluid is described in paragraph [0035] of the patent-in-suit as an optional feature: "The composition may comprise a carrier fluid" (emphasis added). Thus, the Board considers the effect shown by the examples to be applicable to compositions comprising a carrier fluid.

As no objection in this respect was raised by the Appellants, the Board does not have a reason to assume that the posed problem has not been solved over the entire range claimed.

7.5 The remaining question to clarify is whether the effect shown was obvious when starting from the closest state of the art.

Although D6 refers to bleaching, no distinction in bleaching activity of specific particle sizes within the particle size range of 50 to 5000 mym has been shown. Thus, an improved bleaching effect caused by the selection of a specific particle size cannot be derived from this document alone.

The combination of D6 with D19 was regarded by the Appellants to lead towards the claimed invention.

However, when reading the second full paragraph on page 179 of D19, referred to by the Appellants, the following text can be found: "Particle or crystal size is a key variable relating to stability, and can be increased to maximize stability. Increasing crystal size can have a negative impact on rate of solubility, leading to reduced bleaching performance and potentially increased dye damage."

This means that, although the skilled person knows that the reduction of the particle size improves bleaching performance, the skilled person would refrain from reducing the particle size too much, because of stability problems. Thus, this disclosure teaches away from the use of small particles but rather recommends to find a balance. Applying this teaching to the range of 50 to 5000 mym given in D6, it cannot be concluded that a combination of D6 with D19 points towards the use of the range of 10-500 mym.

In addition also the remaining documents cited by the Appellants do not hint towards the use of the average particle size between 10-500 mym to achieve improved bleaching properties.

7.6 Thus, the subject-matter of Claim 1 of the main request involves an inventive step.

7.7 Similar considerations apply to Claims 2-9, which are dependent on Claim 1 and to Claims 10-13 either claiming products comprising the composition according to Claim 1 or to the use of such products.

Amended description

8. Main request

8.1 The Appellants objected, that the examples cited in the description did not contain a carrier fluid, as required by Claim 1 of the main request.

8.2 The Board shares this view, as no hydrophobic oil is present in sufficient amounts to act as a carrier. Thus, a contradiction exists between the wording of the examples and the claims.

8.3 Therefore the requirements of Article 84 EPC 1973 are not considered to be met.

9. Auxiliary request

9.1 No objection with regard to the auxiliary request of the description has been raised by the Appellants. Given the fact, that the objected examples have been marked accordingly, the Board is of the opinion that the description supports the claims.

10. Therefore, the auxiliary request of the description is considered to meet the requirement of the EPC.