T 1268/06 03-02-2009

1. The appeal is admissible.

2. Procedural matters

The Appellant stated in the Statement of Grounds of Appeal that the decision of the Opposition Division was given in contravention of Article 113 EPC because it did not have the opportunity to present comments or provide significant technical answers or consider amendments in reaction to the calculations put forward by the Opponent during the oral proceedings. However the Board notes that the Appellant did not draw any conclusions from this statement and did not file any request based on this alleged violation. The Board itself sees nothing injurious to the Appellant arising out of it, all the more so since according to the minutes of the oral proceedings before the Opposition Division these new calculations filed "upon invitation of the chairman were commented by all parties and by the opposition division step by step". The Patent Proprietor did not at this stage object or submit that it had not had sufficient time.

MAIN REQUEST.

3. Novelty (Article 54 EPC)

3.1 Claim 1 is directed to the use for ballistic protection of an impact resistant composite. It includes the following features:

- a) use for ballistic protection of a composite, the composite comprised of:

- b) more than one layer which is a network of filaments in a matrix, the filaments having

- b1) a tensile modulus of at least 1350 g/tex,

- b2) an energy-to-break of at least 8 J/g, and

- b3) a tenacity equal to or greater than 63 g/tex,

- c) in which composite the ratio of the thickness of the layer to the equivalent diameter of the filaments is equal to or less than 12.8, and

- d) wherein the network of filaments comprises a sheet-like filament array in which the filaments are aligned substantially parallel to one another along a common filament direction and the filament alignments in each adjacent layer are rotated with respect to each other.

3.2 The novelty of this claim has been denied by the Opposition Division in its decision, having regard to the disclosure of D9. Moreover the Respondent maintains that the disclosure of D10 also anticipates the subject-matter of this claim.

3.3 It is common ground (see Appellant's Statement of Grounds of Appeal, point 19 and Respondent's letter dated 20 June 2007, paragraph bridging pages 7 and 8; see also point 2.3 of the decision T 0853/97, the previous decision on this patent) that the ballistic resistant articles disclosed in D9 and D10 include all the features of Claim 1 of the main request with the exception of feature (c), namely that the ratio of the thickness of the layer to the equivalent diameter of the filaments is equal to or less than 12.8 (in this decision called the 'Ratio').

Concerning this feature the Respondent maintains that it is implicitly disclosed in said documents while according to the Appellant the information therein contains no clue as to this feature.

3.4 The only question to be answered in relation to novelty is therefore to establish whether the information in D9 and D10 allows calculation of this 'Ratio' and, if it can be calculated, whether the value obtained falls within the range covered by the claim.

3.5 In the Board's judgment this is indeed the case and the products of examples 1 and 6 of D10 and examples 12, 13 and 14 of D9 disclose products fulfilling all the features of Claim 1 of the main request for the following reasons:

3.5.1 Turning first to D10, a ballistic target is prepared by consolidation of a plurality of sheets comprised of unidirectional, high strength, extended chain polyethylene yarn impregnated with a thermoplastic elastomer matrix (Example 1, sample 1). The polyethylene yarn used is an extended chain polyethylene with a tenacity of 29.5 g/denier, a modulus of 1250 g/denier and energy-to-break of 55 J/g, which is the same polyethylene as that used in example 1 of the patent in suit. It is not disputed that this polyethylene has a density of 0.97 g/cm**(3). The equivalent diameter of the filament can then be calculated by the formula:

weight = volume x density, or, more precisely:

weight of filament = volume of filament x density

(10.2 g/denier) = (pi x radius**(2) x (0.97 g/cm**(3))

length (9000 m))

It follows from this that the diameter of the filament is 0.0039 cm.

3.5.2 In a similar manner the thickness of a single layer can be calculated applying the formula:

weight of composite = volume of composite x density of composite,

wherein the density of composite is 0.96 g/cm**(3) [it contains 72.7% of polyethylene with a density of 0.97 g/cm**(3), the rest being Kraton D 1107 (see column 8, lines 57 - 62) having a density of 0.92 g/cm**(3) so that it can be calculated using the equation (0.727 x 0.97) + (0.273 x 0.92) = 0.96],

and the composite area density is 8.49 kg/m**(2) (see column 14, line 13, Table 2, Sample 1).

By introducing these values into the above formula it follows that the thickness of the overall composite is 0.8844 cm. Taking into account that this composite contains 42 layers [obtained by dividing the fibre areal density of the sample 1 composite, 6.20 kg/m**(2) as given in column 13, line 57 by the fibre areal density of a single layer, 0.148 kg/m**(2) as given in column 8, line 57], it follows that the thickness of a single layer is = 0.0021 cm.

3.5.3 Thus, the ratio of the thickness of one layer to the equivalent diameter of a filament in Example 1 of D10 equals 5.4 (0.0021 cm/0.0039 cm) and is therefore within the range covered by Claim 1 of the main request.

3.5.4 A similar calculation for Example 6 of D10 results in a 'Ratio' of 5.0 for the product therein made.

3.5.5 An analogous lack of novelty conclusion can be drawn on the basis of Examples 12 to 14 of D9. Although in this document neither the precise density of the high density polyethylene used is stated nor is it said whether the composite is made from a yarn with 16 filaments or a yarn with 48 filaments, the Respondent has made calculations for every possible variant covered by the disclosures of Examples 12 to 14 and in every possible variant covered by these examples the value of the 'Ratio' is always below 12.8 (see E11, Table II to IV, the calculated ratio varying from 2.6 to 3.1 for Example 12; from 3.5 to 4.1 for Example 13 and from 4.1 to 4.8 for Example 14).

3.6 The Appellant has objected to the above calculations and argued essentially that

- there is inadequate information in the disclosures of D9 and D10 to derive any particular 'Ratio'. The calculations of the Respondent, which in fact have been modified several times during the proceedings, were based on data which are clearly factually wrong and do not properly address the issue of void space or air entrapment.

- the skilled person would realise from the study of D9 and D10 that he runs into insurmountable obstacles concerning the void volume and would further assume considerable stacking of the filaments resulting in a high ratio.

As a consequence, the skilled person would conclude that the information given in D9 and D10 does not allow the calculation of any ratio.

3.7 These arguments cannot be accepted by the Board:

3.7.1 The alleged presence of voids contradicts the clear disclosure of D10. According to column 7, lines 33 to 61 the laminate prepared using pressure in combination with relatively high temperatures is made of only two components, namely the fibre and the matrix, the matrix material being said to flow and occupy the remaining void spaces (see lines 36 - 37).

3.7.2 As to the presence of crossovers of yarns it is noted that the argument of the Appellant is again in contradiction to the disclosures of D9 and D10. Thus D10 indicates that the yarns are wrapped in a "side-by-side arrangement" around a drum resulting in a "plurality of substantially parallel strands of coated yarn aligned along a common direction" (Example 1, under Precursor Preparation Method 1) and the disclosure of D9 describes "layers of parallel multistrand yarn of high tenacity polyethylene" and "parallel fibers" (column 5, Examples 1 - 6).

3.7.3 It is also noted that the Respondent has presented a further calculation method (see E11, second parts of Tables II - IV) based only on the fibre areal density and thus independent of a potential void content. The results of this alternative calculation method are very close to those discussed above (see 3.5.5) and clearly indicate that, with the possible exception of some minor amounts of voids which may be entrapped somewhere in the composite, no voids are present in the composites of D9 and D10.

3.7.4 Finally, the fact that the Respondent had amended its calculations during the proceedings due to objections of the Appellant which were accepted by the Respondent cannot for that reason question the validity of the calculations as presented above under point 3.5 or in document E11.

3.8 In view of the above, the Board concludes that the ballistic material disclosed in documents D9 and D10 includes all the features of Claim 1 of the main request. The subject-matter of this claim therefore lacks novelty.

FIRST, THIRD, FIFTH AND SIXTH AUXILIARY REQUESTS

4. Amendments

4.1 The subject-matter of Claim 1 of these requests corresponds essentially to the subject-matter of claim 1 of the main request with the only difference that the 'Ratio' (feature c)) is defined respectively as being:

"equal or less than 8" (first auxiliary request), "equal to or less than 6" (third auxiliary request), "from 1 to 5" (fifth auxiliary request), and

"from 1 to 3" (sixth auxiliary request).

5. Novelty (Article 54 EPC).

5.1 As discussed above in relation to the main request the disclosure of documents D9 and D10 includes ballistic protection material having a 'Ratio' in a range varying from 2.6 to 5.4 (see also E11).

5.2 It is evident that this ratio also falls within the range covered by Claim 1 of the above auxiliary requests.

5.3 The subject-matter of Claim 1 of auxiliary requests 1, 3, 5 and 6 is therefore also not novel.

6. Insofar as it might be argued that the calculated 'Ratio' according to example 12 of D9 could be 3.1 and therefore slightly above the range of Claim 1 of the sixth auxiliary request, the Board notes (i) that the majority of the calculated ratio values is below 3.0 indicating that in all probability the "true" 'Ratio' is less than 3, and (ii) that in the absence of any information in the patent in suit as to the criticality for the desired ballistic protection of an upper ratio limit of 3 this value must be considered to be arbitrary and therefore unable to contribute an inventive step (Article 56 EPC).

SECOND AND FOURTH AUXILIARY REQUESTS

7. Amendments (Article 123(2) EPC)

7.1 The subject-matter of Claim 1 of the second auxiliary request corresponds to the subject-matter of Claim 1 of the first auxiliary request but including the restriction that "the filaments do not consist of polyethylene". The subject-matter of Claim 1 of the fourth auxiliary request includes the same restriction of the subject-matter of Claim 1 of the third auxiliary request.

7.2 There is no support for such exclusion in the application as originally filed. On the contrary, polyethylene filaments were one of the preferred embodiments of the application as originally filed (see Claim 15 and working examples). Moreover the amendment made does not fulfil the criteria for allowability of disclaimers as defined in the Headnote of the Decision G 1/03 (OJ EPO 2004, pages 413 - 447) as the disclosures of D9 and D10 are neither accidental nor state of the art under Article 54(3)(4) EPC 1973.

7.3 The Appellant justifies the amendment by reference to the fact that polyethylene is specifically disclosed in the application as originally filed.

7.4 The Board cannot accept this argument of the Appellant. The application as filed relates to the use of polyethylene, but it does not make any reference at all to its exclusion, as now claimed.

7.5 The amendments made to Claim 1 of the second and fourth auxiliary requests do not fulfil the requirements of Article 123(2) EPC and consequently these requests are also not allowable.

SEVENTH TO THIRTEENTH AUXILIARY REQUESTS

8. Amendments

8.1 Claim 1 of the seventh auxiliary request is directed to a method of making an impact resistant composite and Claim 1 of the eighth to thirteenth auxiliary requests modify this method claim in a manner corresponding to the way the first to sixth auxiliary requests modify the 'Ratio', or exclude the use of polyethylene.

9. Framework of the appeal proceedings.

9.1 The present appeal originates from the second decision of the Opposition Division revoking European patent No. 0 397 696. This second decision of the Opposition Division was caused by the admission at a late stage of the proceedings of documents D9 and D10 by the Board of Appeal in decision T 0853/97.

In its first interlocutory decision the Opposition Division had maintained the patent in amended form on the basis of a first auxiliary request filed during the oral proceedings dated 17 March 1997 (see above point V).

9.2 In this first decision the Opposition Division rejected the then main request of the Patent Proprietor because of lack of inventive step of the subject-matter of Claim 1.

9.3 The Patent Proprietor appealed that decision and requested the maintenance of the patent in the form of the main request before the Opposition Division (see second paragraph of page 1 of the Statement setting out the Grounds of Appeal dated 19 August 1997).

9.4 This statement of the Appellant sets out the scope of appeal (Article 108 and Rule 99(c) EPC) and therefore defines the broadest scope of the claims which can be defended by the Patent Proprietor during the appeal proceedings (see G 1/99, OJ EPO 2001, pages 381 - 400, point 6.4).

9.5 The set of claims of this main request defended before the Opposition Division included a product claim directed to an impact resistant composite wherein the filaments were defined as comprising polyethylene or polypropylene (cf. Claim 1) and a further independent claim to the use for ballistic protection of an impact resistant composite wherein the nature of the filaments was not specified (cf. Claim 11).

No method claim was included in this set of claims.

9.6 According to EPO practice an amendment of a granted claim directed to a product to a claim directed to a method of preparation of the product is usually allowed if the method of preparation is limited to the preparation of the products covered by the previous product claim.

9.7 In the present case, the methods according to Claim 1 of the seventh to the thirteenth auxiliary requests are not restricted to the preparation of products containing polyethylene or polypropylene as required by Claim 1 of the main request before the Opposition Division. It also includes embodiments directed to the preparation of impact resistant composites made of other materials, for instance aramid (see Claim 7) and therefore their scope goes beyond that to which the present appeal is limited.

9.8 Consequently, the subject-matter of Claim 1 of all the auxiliary requests seven to thirteen cannot be defended by the Appellant during the appeal proceedings and these requests are not admissible.

10. In summary, none of the Appellant's requests is allowable.