T 0523/00 10-07-2002

Reasons for the Decision

1. The appeal is admissible.

2. Admissibility of the new claims

The wording of the new claim 1 differs from that of claim 1 according to the contested decision by the deletion of the words "or encapsulates" and by the explicit mention of the possible use of either the same or different elastomer(s) for the coating and the matrix. The deleted words were not in the granted claim 1 and were in fact superfluous, since according to the description of the patent in suit a coating is always used, thus implying an encapsulation. The possible use of a single or different elastomeric materials is supported by the passage on page 9, lines 28 to 33 of the description of the patent in suit, as originally filed. The new claim 1 complies with the requirements of Article 123(2) and (3) EPC.

The clarity objections of the respondent are not justified:

- Contrary to the interpretation of the respondent, the expressions "a matrix of an elastomeric material" and "coated with an elastomeric material" in claim 1 do not indicate whether the elastomeric materials for the coating and for the matrix are identical or not. Therefore, the following words " the or each" do not contradict the preceding features.

- The documents of a patent are to be considered as a self-contained whole, giving the words used their normal meaning in the art, unless in particular cases the description gives the words a special meaning. There is nothing in the EPC, which requires that terms used in different patents should have the same meaning. According to Article 69 EPC, the description and drawings of the patent, and not of other patents, shall be used to interpret the claims, that is to say the patent itself is its own dictionary. In the present case, the meaning of the term "fiber" is given in the description of the patent in suit, page 2, lines 55 and 56, together with the passage on page 3, lines 42 to 45, when yarns are implied. It follows that a fibre in the meaning of the patent in suit is the individual smallest element.

- The expression "substantially coated" means that the fibres are more or less completely coated and thus is clear.

- Claim 8 concerns a binding material, which binds a plurality of networks of fibres. Contrary to the view of the respondent, it has nothing to do with the material(s) used for the coating and matrix purposes. Thus, no contradiction appears between claim 8 and claim 1.

Claim 1 consequently is clear (Article 84 EPC) and thus admissible. Claims 2 to 10, which are dependent claims, correspond to claims 2 to 10 as granted, claim 8 being clear.

The amendments concerning the description are of two kinds: all the passages or words which do not correspond to the present invention according to claim 1 were deleted, while the word "comparative" was added to those examples, which do not employ an elastomer material as coating and matrix material. Thus, the new pages of the description are admissible.

3. Novelty

3.1. Verseidag products according to the prior use

During the oral proceedings the respondent has indicated that in the Verseidag products "the yarns are at least coated" and then he grounded his novelty objection on a broad interpretation of the expression "substantially coated" of the contested claim 1, this expression in his view including uncoated fibres in the interior of a yarn. By doing so, he seems to admit that only the yarns of the Verseidag products are coated, not the fibres. However, the requirement of claim 1 of the patent in suit is clear:

each fibre should be substantially coated and according to the description of the patent, when uncoated fibres are grouped together to form a yarn, the group of fibres is pulled through a solution of elastomeric material to substantially coat each of the individual fibres, see pages 3, lines 42 to 46 and the last line of page 5 of the description as granted.

The respondent also argued that the Verseidag products as composites were moulded under pressure and heat conditions and with an elastomer amount, which were more stringent than those described in the description of the patent in suit for the moulding technique, so that, when according to the patent in suit a coating of each fibre should be achieved, this must inevitably be achieved also in the case of the Verseidag products. This argument cannot be followed, since the person skilled in the art, when he knows that he has to form a composite with a particular result in mind, namely to substantially coat each of the fibres and to fill the void volume between the fibres, will not only apply the general conditions of a moulding process, that is to say the needed pressures and temperatures, but he will also take additional measures beforehand according to the circumstances, so as to reach the particular wished result. The kinds of fibres which are used (filament, ribbon, strip,...), the tensile properties of the fibre material, the arrangement of the fibres (knitted, woven or not,..) or of the fibres layers, the configurations of the networks, the nature of the migrating elastomer materials and their capacities to flow into the network, their amounts relative to the fiber contents and so on.., are parameters which are to be considered in such a case and it is up to the skilled person in this technical field to take these appropriate measures, which consequently do not need to be necessarily given in the patent in suit. The respondent, when he has contested during the oral proceedings the calculations of the appellant according to E28, has pointed out the importance of the thicknesses as such of the fabrics of the composite to be moulded and thus confirmed that parameters which are not disclosed in the patent in suit are nevertheless to be considered. It has never been proven that the above mentioned particular required result in its whole was wanted for the Verseidag products and a visual examination of a Verseidag sample referenced W7660 provided by the appellant in case T 857/95 has shown that only the sides of a single fabric were coated, not the core, so that it remains uncertain whether during the moulding of several of theses fabrics together, each of the fibres would have been substantially coated and the void volume between the fibres completely filled. In contrast thereto, the description of the patent in suit indicates that the coated fibres are arranged into a network or can be processed into a simple composite, and that, during the coating technique according to Example 4 of the patent in suit (immersion in a solution of thermoplastic elastomer), the aim was to coat each of the individual fibres (see once more the description, page 5, last lines), contradicting in this respect the opinion expressed in the decision under appeal, last paragraph of page 6. Sample W 7660 has shown that this result was not reached at least with one Verseidag product, although the same technique should have been used according to E26. It is further noted that Mr Veith and document E12a mentioned a coated fabric or a fabric coated on both sides, and not coated fibres. Mr Veith moreover declared that all Verseidag products listed in the Verseidag prospect (E12a), that is to say inter alia the product W7660 as well as the products W7630, W7640 and W7650, were identically treated, so that there is no reason to make a distinction between the Verseidag products according to the prior use, namely those referenced W7630, W7640 and W7650, and that referenced W7660, provided by the appellant.

The respondent has never been able to directly show that the Verseidag products fulfil the above requirement of claim 1, although it had the burden of proof. It always indirectly argued by interpreting in a particular way the above mentioned expression. In its view, this interpretation should also be supported by the fact that the results of Examples 4, 6 and 8 of the patent in suit show ballistic results which are worse than those of the prior art Examples 14, 15 and 17 also described in the patent in suit, showing therefore - according to the respondent - that the matrix in these examples was not completely filling the void volume. However, this last conclusion of the respondent is a mere supposition without any proof, so that this whole argument is to be rejected (see also point 4.1 under).

Therefore, contrary to the conclusion expressed in the first lines of the last paragraph of page 6 of the decision under appeal, it has not been proven by the respondent that, in the Verseidag products, at least each of the fibres was substantially coated by the elastomeric material.

3.2. E24 (DE-A-2 916 745)

In the counter-statement to the grounds of appeal the respondent argued that this prior document destroyed novelty of the composite according to claim 1. However, during the oral proceedings, this document was no longer referred to. In the communication attached to the summons to the oral proceedings, the board made reference to the decision T 857/95, in which for a similar invention the content of E24 was analysed. Briefly, it was indicated that the disclosure of this prior art is too confusing, since the words "a sufficiently soft resin" and "an elastomer" appear separately in one passage of this document, so that the reader of this document does not know whether the qualification "sufficiently soft" applies also to the elastomer. Other disclosures of this document seem to point the reader away from such an interpretation. Moreover, the expression "sufficiently soft" itself is not clear enough to necessarily mean a tensile modulus of the elastomer under the limit given by claim 1 of the patent in suit.

3.3. For all these reasons, the composite according to claim 1 of the patent in suit is new having regard to the above referred prior art disclosures, which were considered by the respondent as novelty-destroying (Articles 52 and 54 EPC).

4. Inventive step

According to the respondent, starting from E15 which represents the closest prior art, the present invention as claimed only differs by the numerical specification of an upper limit of the tensile modulus of the elastomeric material(s) and this feature is either suggested by the above mentioned prior use or has no technical meaning, being the result of an arbitrary choice.

4.1. The present invention

The appellant has not claimed that the tensile modulus limit given in claim 1 is a critical value. Important in his view is only to make a clear distinction between "low" and "high" tensile moduli for the elastomeric materials and this could only be made by choosing a numerical value, which more or less reflects this distinction. The appellant has recognised that it may be that similar ballistic results could be obtained with a higher tensile modulus (10000 psi was mentioned), but the numerical value was also chosen by taking into account the need for a certain flexibility of the composites, which can be used in vests for the police staff. What is important in the present invention is therefore the idea of providing a limit for this parameter of the elastomeric material and to show that the elastomeric material has to be below this limit, that is to say a "soft" elastomer, as defined by claim 1, has to be used.

Moreover, according to the description, the aim of the patent in suit is to provide a ballistic-resistant composite which provides a selected level of ballistic protection while employing a reduced weight of protective material compared to conventional ballistic-resistant armour structures or, alternatively, an increased ballistic protection when the composite article has a weight equal to the weight of a conventionally constructed piece of composite armour. It follows that an improved ballistic protection is not always wanted, so that the argument of the respondent based on the results provided by the Examples 4, 6 and 8 of the patent in suit is not relevant. The description itself of the patent in suit - see the paragraph concerning Example 26 on page 11 - indicates that the ballistic resistance is reduced when twisted yarns are employed as is the case in Example 8 or is good when the yarns are pre-impregnated prior to weaving (Example 4) and even better when straight, uniformly aligned fibres are used (Examples 1, 14, 15 and 17). It shows that the ballistic resistance depends on a great number of criteria, so that comparisons can only be correctly made between examples which show at least a certain number of similarities. It also cannot be denied that, according to the single drawing of the patent in suit (Specified Energy Absorption of a composite in relation with the fibre density area), at least Examples 1, 3 and 13 according to the present invention show substantial improved ballistic properties compared to the same prior art examples.

For these reasons, it cannot be said that the tensile modulus limit as claimed has no significance and is the result of an arbitrary choice.

Moreover, the solution according to claim 1 does not only reside in this feature concerning a selected coating and matrix material. Claim 1 recites three other features, namely selected fibres, a substantial coating of each fibre and the filling of the void volume between the fibres, and the combination of these four features which allows the above mentioned goal to be reached should therefore be considered for the examination of inventive step.

4.2. E15 (EP-A-0 089 537)

As shown by claim 1 of this prior art, which stems from the appellant and designates the same inventors as the patent in suit, the content of this document is essentially directed to the choice of fibres for ballistic resistant materials, which preferably comprise only fibres (lines 1 and 2 of page 4), although composite materials, at least in the meaning of the patent in suit that is to say fibres combined with a major matrix material, are also described on pages 7 and 8 of this document and in some examples. Two main groups of fibres are disclosed, namely polyethylene fibres with a tensile modulus of at least 300 g/denier, preferably 500 g/denier, and a tenacity of at least 5 g/denier, and polypropylene fibres with a tensile modulus of at least 160 g/denier and a tenacity of at least 8 g/denier, an average molecular weight limit being also added.

The use of coated fibres is envisaged - see page 7 -, "a variety of polymeric and non-polymeric materials" forming the coating material; two specified materials which are not elastomers are preferred. The fibres, possibly used with coatings, may be monofilaments or multifilaments. Pages 7 and 8 further indicate that, although large amounts of coating material can be used (1 to 150% by weight of fibres), it is preferred to have a relatively minor proportion of coating (1 to 25%), since the ballistic properties are almost entirely attributable to the fibres.

Complex composite materials are the subject-matter of a single paragraph on page 9, which reads as follows:

"Also suitable are complex composites containing coated fibers in a matrix, with preferred complex composites having the above-described coated fibers in a thermoplastic, elastomers or thermoset matrix; with thermoset matrixes such as epoxies, unsaturated polyesters and urethanes being preferred." No other mention of elastomers appears in this prior art, and in particular in all of the at least twenty examples which follow in this prior art. From data given in Table 1 of Example 1, polyethylene fibres with an energy-to-break above the limit of claim 1 of the patent in suit can be deduced (Examples C to F). The ballistic properties of the composites according to at least Examples 9 and 10 (fibres falling under the definition of claim 1 of the patent in suit, but coated with either low or high density polyethylene and cured under pressure and heat) were compared to a comparative Example 11, identically produced but with aramid fibres, namely Kevlar® 29, coated with a phenolic polyvinyl butyrol resin. The conclusions as set on page 15 are that the ballistic performance between the three tested examples are comparable, but, "since it is known to produce polyethylene fibers with higher tenacity" (30 g/denier or more, compared to the 22 g/denier of Kevlar® 29), "it is expected that these fibers would substantially outperform aramid fibers for ballistic applications". An identical conclusion is given with Example 20.

4.3. Differences between the disclosure of E15 and the present invention according to claim 1.

The respondent has recognised that the tensile modulus limit mentioned in claim 1 of the patent in suit for the elastomeric material(s) is not disclosed by E15. However, as far as the coating and matrix materials are concerned, the teaching of E15 is quite silent on the tensile moduli of these materials. It is not because some examples of E15 may comprise matrix materials with a tensile modulus under the claimed limit that the requirement as such for "soft" elastomeric materials within the meaning of claim 1 of the patent in suit, or even for "soft" matrix materials is suggested. On the contrary, as seen above, the sole mention in E15 of elastomers appears together with thermoset materials, which according to the examples listed in the last sentence of the above given passage of page 9 are hard matrix materials, so that E15 in fact directs the skilled person toward the use of these hard matrix materials, which are said to be preferable, elastomers being not preferred.

Fibers falling within the scope of the contested claim 1 are indeed disclosed by E15; the description of the patent in suit expressly mentions polyethylene and propylene fibres as two important groups of fibres of the present invention. However, this description also discloses other groups of fibres, for example aramid fibres like Kevlar® 29, which are used in the examples of the patent in suit. Above all, Claim 1 of the patent in suit gives a definition of the fibres, which is not disclosed in E15; for example, no mention of the parameter energy to break appears in E15, which further does not suggest the limit 500 g/denier for the tensile modulus of the fibres as selection parameter: in E15 it is only a preferred value for the polyethylene fibres. It follows that claim 1 gives a selection of fibres which is different from that of E15.

Moreover, the whole combination of features of claim 1 is new: it is not because E15 discloses separately that the fibres could be coated or that the matrix may occupy all the void space left by the fibres and could be made of elastomers, that E15 teaches or suggests that these conditions should be linked together as requirements and further be combined with a selected kind of fibres, which only overlaps partly the selection of fibres disclosed in E15. When the respondent brings together these four conditions on the basis of pieces of information separately gathered from E15, he makes an a posteriori assessment, which is not admissible.

Therefore, claim 1 differs not only by the mention of an upper limit for the tensile modulus of the elastomeric materials, but also by the whole claimed combination of features as such. It is even doubtful whether E15 suggests to the person skilled in the art to substantially coat each of the fibres, said fibres being the smallest elements of the network, having regard to the passage of page 7 of this prior art, which indicates that the fibers may be monofilament or multifilaments.

4.4. It follows that the combination of E15 with the disclosure of the prior use is not sufficient to reach the subject-matter of claim 1 of the patent in suit, since the Verseidag products do at least not teach to substantially coat each of the fibers within the meaning of the patent in suit, whereas E15, page 8, directs the person skilled in the art to rather coat the fibres "with a relatively minor proportion of coating".

4.5. Furthermore, it is not clear for which reason the person skilled in the art would combine these two prior art disclosures:

E12a is a prospect of a firm, the aim of which being to attract the potential customers toward the Verseidag products which comprise Kevlar® 29 fibres. The mere mention of good ballistic properties without technical data would be considered by the person skilled in the art before all as an advertising means. E12a moreover does not indicate the reasons for the said improved ballistic properties. Thus, when E15 teaches that "hard" matrix materials are preferable rather than elastomers or other materials and that polyethylene fibres with high tenacity are preferred to Kevlar® 29 fibres, thus directing the skilled person in at least two directions which differ from the disclosure of the Verseidag products, a combination of these two disclosures is not logical.

4.6. The subject-matter of claim 1 of the patent in suit, therefore, involves an inventive step within the meaning of Article 56 EPC. Claims 2 to 10, which are dependent on claim 1, concern the same composite with additional features and consequently are allowable.