T 1007/96 12-11-1998

I. The appellant (opponent) lodged an appeal against the decision of the opposition division rejecting the opposition filed against European patent No. 346 113.

Opposition was filed against the patent as a whole and based on Article 100(a) EPC in conjunction with Articles 54 and 56 EPC (lack of novelty and inventive step).

The opposition division held that the grounds for opposition mentioned in Article 100(a) EPC did not prejudice the maintenance of the patent, having regard to the following prior art documents

E1: EP-A-0 216 415,

E2: EP-A-0 248 341,

E3: EP-A-0 269 543,

E4: US-A-4 588 080,

E5: FR-A-2 579 956,

E6: FR-A-2 563 250,

E7: DE-U-85 09 898,

E8: GB-A-2 157 717 (equivalent to E6),

E9: EP-A-0 266 199, and

E10: JP-A-50-75 567 together with its German translation.

II. During the appeal procedure the appellant filed an additional prior art document (E11 = DE-U-70 41 742) to further support the objection of lack of an inventive step.

III. Oral proceedings were held on 12 November 1998.

The appellant (opponent) requested that the decision under appeal be set aside and that the European patent No. 346 113 be revoked.

The respondent (patentee) requested that the appeal be dismissed and that the patent be maintained on the basis of Claims 1 to 6 filed at the oral proceedings (main request), or Claims 1 to 6 filed at the oral proceedings as auxiliary request A, or two sets of claims B and C as filed on 12 October 1998.

Independent Claims 1 and 6, according to the main request, read as follows:

"1. A process of washing fabrics in a washing machine which comprises introducing a quantity of liquid detergent, having a viscosity of from more than 0.3 to 20. newton seconds per square metre (300 to 20,000 centipoise) as measured at a low share rate at 25 C, into an open topped vessel in which the open upper aperture of the vessel is 20 to 40% of the area of the remaining external surface area of the vessel through the open top, placing the vessel containing said liquid detergent and the fabrics to be washed in said washing machine, carrying out a washing process in the presence of the said vessel without either wholly or partially closing the open top or securing the vessel to any part of the washing machine, and removing said vessel from the washing machine after the washing process."

"6. A package of liquid detergent for laundry use which comprises a bottle containing a liquid detergent of viscosity of 1.5 to 10 newton seconds per square metre (1,500 to 10,000 centipoise) as measured at a low share rate at 25 C, means to close the bottle and in addition to said means a vessel which has no external projections, is made of a breakage-resistant material and is calibrated to indicate suitable quantities of detergent for use in a washing machine, detachably secured to the bottle and constituting whilst secured to the bottle, a secondary means to close the bottle and which on removal from the bottle has an open top, the open upper aperture of the vessel being 20 to 40% of the area of the remaining surface area of the vessel."

IV. The appellant argued essentially as follows:

Document E3 represented the closest prior art on file. Said document disclosed a process of washing fabrics in a washing machine which comprises introducing a quantity of liquid detergent into an open topped vessel through the open top, placing the vessel containing said liquid detergent and the fabrics to be washed in said washing machine, carrying out a washing process in the presence of the said vessel, without securing the vessel to any part of the washing machine, and removing said vessel from the washing machine after the washing process.

The problem underlying the invention was to be seen in the fact that, having regard to the higher viscosity of the liquid detergents involved in the washing process according to the patent in suit, the vessel according to prior art document E3, which showed open upper apertures having a smaller total area, did provide for a too slow release of the detergent, i.e. for a too long amount of the time necessary for ensuring the total release of the adequate quantity of such detergents, when poured into such a prior art vessel.

The person skilled in the art was taught, by document E3 in combination with document E7 and by the general teaching from the other prior art documents on file, that the dimensions of the upper apertures of the vessel should be defined in such a manner as to show a suitable total area, i.e. a total area in accordance with the viscosity of the liquid detergent involved in the washing process and with the suitable amount of time, necessary to provide for the total release of the adequate quantity of detergent involved in the washing process and poured into the vessel.

According to the above, the person skilled in the art would have tried to modify the vessel according to prior art document E3 in such a manner that the total area of its upper apertures would result in accordance with the viscosity of the liquid detergent involved in the washing process and with the suitable amount of time, necessary to provide for the total release of the adequate quantity of detergent involved in the washing process and poured into the vessel. He would have, thus, defined the value of said total area by way of experiments, which did not involve an inventive step.

Furthermore, the aperture ratio defined in Claim 1 was not in a casual relationship with the wanted effect of avoiding slow detergent release. A quick detergent release was dependent not only on the claimed aperture ratio, but also on the configuration of the vessel. Therefore, Claim 1 did not contain a clear and complete technical teaching.

V. The respondent argued essentially as follows:

The overall teaching provided by the various prior art documents on file - E3 and E7 in particular - was that dosing devices (vessels) for liquid detergents should deliberately slow down the release of detergent into the washing bath, during laundry operations, and the devices appropriate for this were relatively complex, owing to the deliberate and compulsory presence of some structural means intended for closing, at least partially, their upper apertures, before said vessels might be introduced into the washing machine and participate to the washing process.

The opposed patent approached the release of detergents in laundry from a quite different direction -quick instead of slow release- and the result was a simplified way of introducing liquid detergents; contrary to the teaching of the various prior art documents on file, because it involved the total suppression of any kind of structural means intended for closing the upper aperture of the vessels.

In the context of the various prior art documents on file, it appeared that simplicity was the major merit of the invention and its simplicity positively supported the existence of an inventive step.

Claim 1 was also clear. With respect to the "aperture ratio", said claim prescribed an unambiguous relationship defining the dimension of the "free area" of the upper opening of the vessel. The expression "open topped vessel" unambiguously meant that the vessel had an open top, without any whatsoever cover or lid.