T 1525/15 14-01-2020

Summary of Facts and Submissions

I. Opponent 2 filed an appeal against the decision of the opposition division on the amended form in which European patent No. 1 187 716 ("the patent") could be maintained.

The opposition division was of the opinion that claims 1 and 7 of the patent as granted (main request) did not comply with the requirements of Article 123(2) EPC but that the first auxiliary request complied with the requirements of the EPC.

Of the prior art documents taken into account by the opposition division, documents WO 99/44814 ("D1") and WO 97/27365 ("D5") are particularly relevant for the appeal proceedings.

II. On 23 November 2018 the parties were summoned to oral proceedings to be held on 5 November 2019.

III. In its communication pursuant to Article 15(1) of the Rules of Procedure of the Boards of Appeal (RPBA) issued on 10 May 2019, the board expressed its provisional opinion on the case.

IV. Both the appellant and the respondent informed the board that they would not attend the oral proceedings (letters dated 4 July 2019 and 12 July 2019, respectively). The board then informed the parties that the oral proceedings had been cancelled and that the decision would be taken in writing.

V. The appellant (opponent 2) requested that the decision under appeal be set aside and the patent be revoked.

The respondent (patent proprietor) requested that the decision under appeal be set aside and the patent be maintained in amended form on the basis of the description as attached to the decision of the opposition division and the set of claims filed by letter dated 4 July 2019.

The party as of right (opponent 1) filed no requests.

VI. The independent claims of the sole request on file read as follows:

"1. A method for the production of a multi-ply web material comprising at least two embossed plies joined together, including the steps of:

- embossing a first ply (V1), by forming a first set of protuberances (V1p);

- embossing a second ply (V2), by forming a second set of protuberances (V2p);

- applying an adhesive between said two plies (V1p, V2p);

- laminating the two plies together and joining them by gluing;

characterised in that

• said protuberances of the first set (V1p) are of limited size and high density and form a micro-embossing design on said first ply (V1);

• said protuberances of the second set of protuberances (V2p) have larger sizes and a lower density than the first protuberances (V1p);

• said second ply (V2) is free of a microembossing design;

• and the first ply (V1) does not undergo a second embossing, but only a flattening of the protuberances (V1p) of said first set where they meet the protuberances (V2p) of the second set during lamination;

wherein said second ply (V2) is embossed between an embossing cylinder (9) and a pressure cylinder (11) having a yielding outer cylindrical surface; and wherein said two plies are laminated between said embossing cylinder (9) and a laminating cylinder (13) whose outer cylindrical surface has a greater hardness than that of said pressure cylinder (11)."

"6. An embossed web material comprising at least two embossed plies joined together, a first ply (V1) having a first set of protuberances (V1p), and a second ply (V2) having a second set of protuberances (V2p) facing the interior of the web material, said two plies being glued together at the positions of at least some of the protuberances (Vp2) of said second set; characterised in that

• the protuberances of said second set (V2p) have larger sizes and a lower density than the protuberances (V1p) of said first set, said protuberances (V1p) of said first set forming a micro-embossing;

• said second ply (V2) is free of a micro-embossing design;

• and said protuberances of said first set are flattened where they meet the protuberances (V2p) of said second set, but said first ply (V1) not being subjected to a second embossing."

For concision, the last feature will be referred to in the following as the "flattening feature".

VII. The appellant filed a series of objections against the set of claims which the opposition division had found to comply with the requirements of the EPC. In the following only the objections that apply to the request filed by the respondent in a letter dated 4 July 2019 are presented:

(a) Compliance with Article 123(2) EPC

Claims 1 and 6 of the patent comprise the feature "said second ply is free of microembossing". This feature was not disclosed explicitly or implicitly in the application as filed.

The opposition division acknowledged that the feature was not explicitly disclosed in the original application (see end of page 9 of the decision under appeal). The opposition division was wrong to consider that it was implicitly disclosed.

As the description does not mention the structure of the plies at the beginning of the process, the skilled person is free to consider two alternatives: (1) the second ply is pre-embossed, or (2) it is free of embossing at the beginning of the process. Therefore, there is an ambiguity. Consequently, the feature under consideration fails the "novelty test". The argument that the skilled person would have envisaged the most simple realisation goes beyond the novelty test.

The feature is also not implicitly disclosed in Figure 4 either. A negative feature cannot be drawn from a schematic drawing (T 170/87). The ply is "free of micro-embossing" just because only "large embossings" are represented on the second ply. Furthermore, Figure 4 is also ambiguous. It shows a roll on which a web is wound. The portion of web which has been pulled from the roll shows a second ply that has a large embossment in form of flower and a first ply with micro-embossing represented by dots. But on the portion of web which is still wound onto the core of the roll, said second ply is represented by a series of dots which are similar to the dots shown on the first ply. The most natural interpretation would be to consider the dots as micro-embossing. The opposition division interpreted them as a "shadow". As there are several possible interpretations, the feature cannot be said to be directly and unambiguously disclosed.

The feature was added during the examination in order to overcome a novelty objection with respect to document D1, which is state of the art under Article 54(3) EPC. It cannot be considered to constitute an allowable disclaimer. Document D1 does not qualify as "accidental anticipation"

In conclusion, claims 1 and 6 extend beyond the scope of the claims as filed.

(b) Clarity

Claim 6 is a product claim concerning a web material. The claim lacks clarity because the feature "said protuberances of said first set are flattened where they meet the protuberances of said second set" is a method feature and not a product feature. The feature is meaningful only if it is possible to compare the "flattened" protuberance before the flattening operation with the protuberance after the flattening operation. Otherwise it is not possible to ascertain that there was a flattening operation. This interpretation is reinforced by the wording "where they meet" used in method claim 1. The feature "where they meet" was replaced by "in correspondence" in claim 7 as granted. The wording "in correspondence" is a product feature since this term refers to a static result. In contrast, the wording "where they meet" strongly suggests a displacement of the protuberances of the second set towards the protuberances of the first set before they contact each other at a meeting point. However, claim 6 concerns a product. It is therefore impossible to know from a sample of web if two protuberances glued "tip to tip" and which present a flat tip have been "flattened" as in claim 1 or if they have been glued together while their tip was already flat (for such an embodiment see for example Figure 9 of D1 or Figure 3 of document D5). It is also impossible to know from a sample of web if the protuberances of the first set were displaced towards the protuberances of the second set during the fabrication process. Thus, claim 6 as maintained is not clearly defined and contravenes Article 84 EPC.

(c) Insufficient disclosure

In order to carry out the claimed method and obtain the web material product, it is not sufficient for those skilled in the art, who have a lot of experience in embossing paper plies and combining them, to use their experience to be able to achieve flattening without a second embossing.

There is no technical teaching in the specification relating to the specifics of the non-second embossing of the first ply, i.e. how it could be carried out, in particular in the zones where there is a flattening of the first protuberances. The flattening of the protuberances of the first set without second embossing occurs between cylinder 9 and cylinder 13 shown in Figure 1 of the patent.

The only information regarding the laminating cylinder 13 is that it is provided with a surface the hardness of which is greater than the hardness of the surface of the pressure cylinder 11 ([0025]) and that it can be made of rubber ([0025] and hatching of Figure 1). This means that the cylinder 13 has a yielding surface, albeit less elastic than that of cylinder 11. Cylinder 9 is made of steel ([0024]). The description does not give any information about the nip between cylinder 9 and cylinder 13. Consequently, there is a good chance that the protuberances 9p of cylinder 9 press into the yielding surface of the laminating cylinder 13:

FORMULA/TABLE/GRAPHIC

Thus it is unlikely that the web of Figure 2 is obtained without a second embossing of the first ply:

FORMULA/TABLE/GRAPHIC

A "tip to tip" process as in document D5 is technically very difficult to carry out. The setting of the angular position and the gap/nip between the embossing rollers is described as "an acute technical problem" by the opposition division. Similarly, the adjustment of the elasticity of the yielding surface of the laminating cylinder 13 and the gap/nip between cylinder 9 and 13 is also an acute technical problem which cannot be solved from the description. Such results are far beyond the reach and knowledge of the skilled person. If it was a simple matter of selecting parameters (such as pressure, hardness, speed, density), for instance starting from the teachings of D5, the invention would lack inventive step. If the flattening feature meant crushing the whole overlapping areas so that the micro-protuberances do not exist anymore, then the high pressure of such flattening / crushing would certainly result in a second embossing of the first ply.

(d) Lack of novelty

The subject-matter of claim 6 lacks novelty over the disclosure of document D5.

Document D5 discloses an embossed web material comprising at least two embossed plies joined together (page 1, first paragraph), a first ply 10 having a first set of protuberances 12, and a second ply 20 having a second set of protuberances 22 facing the interior of the web material. These two plies are glued together (page 3, last paragraph) at the positions of at least some of the protuberances 22 of said second set. The protuberances of the second set 22 have larger sizes (page 3, line 26: "l'empreinte est linéaire" along with Figure 2) and a lower density than the protuberances 12 of the first set (page 3, line 23: "inférieur à 2000 par m**(2)"). The protuberances 12 of the first set form a micro-embossing (page 3, line 12: "au moins 30 par cm**(2)" which corresponds to the density given in [0023] of the patent). The second ply V2 is free of a micro-embossing design (page 3 line 24: "portion de surface lisse"). The protuberances 12 of the first set are flattened where they meet the protuberances 22 of the second set, but the first ply 10 is not subjected to a second embossing.

This last feature has to be analysed in view of product claim 6 and not in view of method claim 1. Since the term "flatten" has to be interpreted as a "product feature", it means "presenting a flat tip". As represented in Figure 3 of D5, the protuberances 12 of the first set do in fact have a flat tip "where they meet the protuberances of the second set".

(e) Lack of inventive step

The subject-matter of claim 6 at least lacks inventive step over the disclosure of document D5.

The flattening feature does not confer any technical effect or advantage to the web material. Therefore, there is no technical problem, no technical effect and no inventive step.

To defend the inventive step of claim 6, the opposition division used an argument that related to the method for producing the web. However, claim 6 is a product claim. There is nothing that would make it possible to establish a difference between a web obtained by the process of the patent and a web obtained by the process of document D5.

VIII. The respondent argued as follows:

(a) Compliance with Article 123(2) EPC

The application as originally filed discloses in detail on page 7, lines 10-24, the manufacturing process, according to which the first web V1 is fed to the first embossing unit 1 and is embossed between rollers 3, 5 so as to be given a micro-embossing design with protuberances corresponding to protrusions 3P. The micro-embossed web V1 and the micro-embossed protuberances V1P thereof are clearly shown in Figure 2. According to the description, page 7, line 16, the second ply V2 is embossed between the pressure cylinder 11 and embossing cylinder 9. The protuberances formed in this way are shown at V2p in Figure 2.

The very purpose of Figure 2 is to show the actual embossing structure of the web. It is clear from Figure 2 that the two plies V1 and V2 do not include any additional embossing patterns, except those formed by micro-embossing V1p and by the decorative embossing V2p.

The representation of Figure 2 in combination with the description of the embossing method on page 7 informs the skilled reader clearly and unambiguously that the second ply V2 is free of micro-embossing.

The description does not mention the structure of the first and second plies at the beginning of the process. The skilled person would be free to consider any alternative: the first and second plies may be free of embossing before being fed into the disclosed process or pre-embossing may be present. The skilled person would at least envisage the simplest realisation in which the process is started from the first and second plies free of any pattern.

Thus, the feature of the second ply being free of micro-embossing meets the novelty test and is supported by the original application.

Moreover, starting the disclosed embossing process by using first and second plies which are free of previously generated embossing patterns is the only embodiment consistent with Figure 2. The very purpose of this figure is to show the resulting final multi-ply web. No other embossing patterns are shown in Figure 2, except those formed by protrusions V1p and V2p. This conveys to the skilled reader the clear and unambiguous teaching that the second ply V2 is free of micro-embossing.

Figure 4 is not the only figure of the final product obtained by the method. Figure 2 contains additional information on the embossing patterns of the two plies V1 and V2.

The contested feature can therefore be derived clearly and unambiguously from the application as originally filed.

(b) Clarity

The flattening feature is clearly understood by the skilled person to be a structural feature of the final product.

The feature actually defines a feature of the final product, once it has been processed according to the method as claimed in claim 1 and as disclosed in the patent. The appearance of an embossed product is the direct consequence of the embossing method used. If a tissue paper ply is firstly micro-embossed by the rollers 3 and 5 of the micro-embossing unit 1 (see Figure l) and subsequently laminated between the lamination roll 13 and the protrusions 9P of the embossing roller 9, the consequence is that the micro-embossed protrusions V1p generated in the first ply V1 are subject to a flattening operation. The result is clearly visible in the final product. Thus, for the skilled reader the contested sentence defines a step of a paper converting method as well as a feature of the final product obtained by the converting method.

The term "where they meet", also has both a static and a dynamic meaning. The protrusions of the two plies are brought together during the embossing process, such that the two sets of protrusions meet one another. At the end of the process, the protrusions meet one another. Also in this case, the contested feature would be clearly understood by the skilled reader as a structural feature of the final product.

(c) Insufficient disclosure

The skilled person would have known how to carry out the invention.

The question of sufficiency of disclosure has to be evaluated on the basis of the content of the patent as a whole, taking into consideration common general knowledge.

In the present case, the skilled reader is a mechanical engineer with a university degree and several years experience in the field of embossing machines. Those skilled in the art are expert in the fundamentals of paper making and paper converting technology. They know that embossing is a technique used in paper converting for permanently modifying the structure of a cellulosic web. They also know that embossing is achieved by passing paper plies in embossing nips formed by an embossing roller having embossing protrusions on the cylindrical surface thereof, and a pressure roller having a yielding coating. Embossing is obtained by the protrusions penetrating into the yielding coating layer of the pressure roller.

Any mechanical engineer would know that materials deform when a force is applied to them. The deformation may be elastic or permanent. An elastic deformation recovers once the force applied to the material causing the deformation has been released. A permanent (plastic) deformation occurs when the so-called elastic limit or yield limit has been reached, i.e. when the applied stress causes a permanent deformation of the material. The permanent deformation does not recover once the force has been removed, i.e. the material will remain permanently deformed.

This is also true for paper, which is a material formed by cellulosic fibers. Embossing is achieved when the embossing protrusions penetrate into the yielding coating of the pressure roller to such an extent that the paper ply passing between the embossing roller and the pressure roller is deformed beyond the yield point. The more the protrusions penetrate into the yielding coating of the pressure roller, the more the paper will be permanently deformed.

Those skilled in the art know that the displacement of cellulosic fiber displacement can be controlled by modifying two parameters: the hardness of the surface of the pressure roller and the pressure on the area of contact between the embossing protrusions and the yielding surface of the pressure roller. They are perfectly capable of selecting the hardness of the laminating roller 13 and the linear pressure (N/m) between rollers 9 and 13 in order to achieve flattening with no re-embossing of the micro-embossing protrusions.

It should be noted that these parameters vary depending upon the actual embossing pattern. The larger the front surface of the embossing protrusions 9P, the smaller the local pressure (N/m**(2)) at the point of contact, the linear pressure (i.e. the force per linear unit of the line of contact between rollers 9 and 13) being the same. Once the embossing pattern is defined, those skilled in the art can easily find the correct pressure between the rollers 9 and 13 for a given hardness of the roller surface, by a simple routine test. This is particularly relevant because modern embossing machines have electronic control means for controlling the pressure between embossing rollers and pressure rollers. It is simply a matter of iteratively changing such pressure on the fly, i.e. while the embossing unit is operating, by means of a simple operator interface, until the desired result is achieved.

(d) Lack of novelty

The subject-matter of claim 6 is new over the disclosure of document D5.

The feature "the protuberances of the first set are flattened where they meet the protuberances of the second set" of claim 6 must be interpreted in light of the description and drawings. The appellant's interpretation is clearly incorrect and at odds with the content of the patent as a whole. The patent clearly teaches that "flattened" means that the protrusions in question have been squeezed back and crushed, thus "destroying" their shape as obtained by the previous micro-embossing.

It should be noted that the claim requires the micro-embossing protrusions V1p to be flattened "where they meet the protuberances V2p of the second set". This implies a different structure of the micro-embossing protrusions: those located in front of the protrusions V2p are flattened, while others are not. This has nothing to do with the flat tip of the protuberances.

(e) Lack of inventive step

The subject-matter of claim 6 does not lack inventive step over the disclosure of document D5.