T 0525/17 (Thin film with non self-aggregating uniform heterogeneity/MONOSOL) 21-01-2021

1. Main request - Article 123(2) EPC

1.1 Claim 1 has been amended in comparison to claim 1 as granted by adding the following feature in bold in step (c):

"(c) drying said film from the bottom of said film to the top of said film at a temperature of 100 °C or less by applying heat to the bottom side wherein the drying forms a solid, visco-elastic structure during an initial setting period which occurs within the first 0.5 to 4 minutes".

Corresponding amendments were made to independent claims 25, 31, 44 and 49.

Said feature is explicitly disclosed in the original description on page 36, lines 6-11. The cited passage belongs to the part of the original application entitled "Drying of the film" starting on page 35, and relates therefore directly and explicitly to the drying step (c) as claimed. Said passage reads:

"Desirably, substantially no air flow is present across the top of the film during its initial setting period, during which a solid, visco-elastic structure is formed. This can take place within the first few minutes, e. g. about the first 0.5 to about 4.0 minutes of the drying process."

In view of this passage, the subject-matter of step (c) present in claim 1 and in the other independent claims is derivable directly and unambiguously from the application as originally filed.

1.2 The Board could in particular not see in the incorporation of said feature "wherein the drying forms a solid, visco-elastic structure during an initial setting period which occurs within the first 0.5 to 4 minutes" an unallowable intermediate generalization as argued by the respondent 01.

According to the respondent 01, the technical feature "substantially no air flow is present across the top of the firm during its initial setting period" was disclosed in the same passage in close context with the time period of 0.5 to 4.0 minutes, but was nevertheless omitted.

The Board notes that the feature, being introduced by the word "desirably" is an optional one, and is thus not inextricable linked with the feature of step (c).In addition, step (c) as claimed comprises a direct reference to this aspect of the drying step by specifying precisely that the drying heat originates exclusively from the bottom of the film, thus implicitly without any air flow across the top of the film. This aspect of the drying is indeed immediately derivable from the feature "(c) drying said film from the bottom of said film to the top of said film at a temperature of 100 °C or less by applying heat to the bottom side".

It is therefore not possible to see in the introduction of the feature "wherein the drying forms a solid, visco-elastic structure during an initial setting period which occurs within the first 0.5 to 4 minutes" an intermediate generalization, even less an unallowable intermediate generalisation.

1.3 Consequently, the main request meets the requirements of Article 123(2) EPC.

2. Main request - Article 123(3) EPC

2.1 Interpretation of the independent claims as granted

Independent claims 1 as granted related to a film formed by a process with a terminal drying step as follows:

"(c) drying said film from the bottom of said film to the top of said film at a temperature of 100 °C or less by applying heat to the bottom side wherein the drying occurs within the first 0.5 to 4.0 minutes."

The same feature of step (c) was present in the further independent claims 25, 31, 44 and 49.

2.1.1 In step (c) of all independent claims as granted, the presence of the term "first" is a clear indication that the drying step lasts longer than 0.5 to 4 minutes and might comprise further steps. Hence, the presence of the term "first" excludes clearly and logically that the claimed time range of 0.5 to 4 minutes applies to the whole drying process and distinguishes said whole drying process from a more limited drying step, namely the "drying [which] occurs within the first 0.5 to 4 minutes".

The presence of the term "wherein" furthermore links the time range of "the first 0.5 to 4 minutes" to the specific drying of the bottom side of the film and not to the whole drying step c), and confirms thereby the existence of an initial period of the drying process.

Consequently, the interpretation of step c) of the independent claims as granted leads to the conclusion that the whole drying does not take place in its entirety during the first 0.5 to 4 minutes, as stated by the opposition division in its decision and argued by the respondent, but said claimed time range relates instead to a initial period of the overall drying process.

2.1.2 Even if the basis for interpretating the subject-matter of a claim and its consequent scope lies in the strict, literal meaning of the claims, the interpretation as given above appears consistent with the disclosure of the description of the application as filed. The description on inter alia page 36, lines 6-11 highlights the existence of an initial setting period of the drying, by stating it explicitly in said passage; the same passage also excludes explicitly that the time range of 0.5 to 4 minutes applies to the whole drying process, and suggests that it applies to an initial setting period:

"substantially no air flow is present across the top of the film during its initial setting period, during which a solid, visco-elastic structure is formed. This can take place within the first few minutes, e. g. about the first 0.5 to about 4.0 minutes of the drying process". Said interpretation is also consistent with the disclosure of the examples which show a drying time of about 4 to 6 minutes in examples A-I, while the same process is used in examples J-L.

This interpretation is furthermore not inconsistent with the subject-matter of dependent claims 5 or 6, contrary to the argumentation of respondent 01. Said dependent claims respectively require that "said drying of said film reduces the weight percent of water to about 8 % or less" or "said drying of said film reduces the weight percent of water to about 6 % or less". Respondent 01 observed that according to the sentence of the description following Table 1, the drying to less than about 6% by weight water takes place in about 4 to 6 minutes. However, according to the wording of dependent claims 5 or 6, this water reduction refers indeed to the whole drying process claimed in step c), and not to the initial setting period. Thus, the interpretation of claim 1 provided above, is not at variance with the content of claims 5 and 6.

2.2 The independent claims of the main request

In claim 1, as well as in the other independent claims 25, 31, 44 and 49 of the main request, said step (c) has been modified by the following feature in bold in step (c):

"(c) drying said film from the bottom of said film to the top of said film at a temperature of 100 °C or less by applying heat to the bottom side wherein the drying forms a solid, visco-elastic structure during an initial setting period which occurs within the first 0.5 to 4 minutes".

In view of the interpretation of the independent claims as granted given above, the introduction of the feature "forms a solid, visco-elastic structure during an initial setting period" is a specification of the initial drying setting period which occurs during the first 0.5 to 4 minutes. It gives a further detailed description of what was meant by said initial drying period, namely that it forms a solid, visco-elastic structure. The introduction of this feature introduces therefore a further restriction to the drying step (c), and it is not possible to see in this amendment an extension of the scope of the claim.

Moreover, the scope of step c) has not changed, since it relates, in the preamble of step (c), still to "(c) drying said film from the bottom of said film to the top of said film at a temperature of 100 °C or less", and the further incorporation of any feature relating to any more limited step encompassed by the whole drying step (c) cannot extend the scope of step (c) as present in all independent claims as granted.

Consequently, the main request meets the requirements of Article 123(3) EPC.

3. Main request - Article 84 EPC

3.1 According to respondent 01, all independent claims of the first auxiliary request lack clarity, since the specific point of time when the initial setting period of drying step c) is finished needs to be determined and it is necessary to evaluate at what point of time the "solid, visco-elastic" structure is formed, which further requires to know when a structure is "solid" and "visco-elastic" and what is meant by these terms.

3.2 The question to be answered with respect to clarity under Article 84 EPC is whether it is possible to determine if an embodiment falls within the scope of the claims or not, i.e. to determine in the present case when the initial setting period of drying step c) has formed "a solid, visco-elastic structure".

The terms "solid" and "visco-elastic" defining the structure formed within the first 0.5 to 4 minutes are commonly used in the art and therefore understandable by those skilled in the art. The skilled person would indeed understand that "a solid, visco-elastic structure" relates to a firm non-liquid structure being both viscous and elastic and would be able to determine when the formation of such structure has occurred. The absence of a quantitative definition for the term "visco-elastic" may result in a weak restrictive function, but this does not imply a lack of clarity of the claims.

Consequently, the evaluation at what point of time the "solid, visco-elastic" structure" is formed is within the scope of the skilled person, and the term "wherein the drying forms a solid, visco-elastic structure during an initial setting period which occurs within the first 0.5 to 4 minutes" is clear. The main request thus meets the requirements of Article 84 EPC.

4. Remittal to the opposition division

4.1 As mentioned above, the main requests meets the requirements of Articles 123(2), 123(3) and 84 EPC. However, the main request has not yet been examined with regard to the remaining grounds of opposition under Article 100(a) EPC and Article 100(b) EPC, since the decision of the opposition division only related to the allowability of the amendments under Articles 123(2) and 123(3) EPC.

4.2 Under Article 111(1) EPC, the Board may in the present case either proceed further with the examination of the application, or remit the case to the opposition division for further prosecution.

Since the present appeal was pending on 1 January 2020, the revised version of the RPBA applies (OJ EPO 2019, A63), subject to the transitional provisions set out in Article 25 of said RPBA. In particular Article 11 RPBA 2020 is applicable. Article 11 RPBA 2020 provides that the Board shall not remit a case to the department whose decision was appealed for further prosecution, unless special reasons present themselves for doing so. The Board holds that such special reasons are apparent in the present case.

The provision of Article 11 RPBA 2020 has indeed to be read in conjunction with Article 12(2) RPBA 2020, which provides that it is the primary object of the appeal proceedings to review the decision under appeal in a judicial manner (see also T 1966/16, point 2.2 of the reasons, T 547/14 points 7.1 and 7.2, and T 275/15 point 4. of the reasons). This principle would not be respected if the Board were to conduct a complete examination of the application.

4.3 As discussed above, in the present case the opposition division decided only on the grounds of opposition under Article 100(c) EPC and did not consider the further grounds of opposition, which were also not presented by the respondent in the appeal proceedings. Said grounds under Article 100(a) EPC and 100(b) EPC were also not discussed during the oral proceedings before the opposition division. Moreover, both the appellant and respondent 01 have requested that the case be remitted to the opposition division for further prosecution.

Under these circumstances, the Board considers it appropriate to exercise its discretion under Article 111(1) EPC and to remit the case to the opposition division for further prosecution.