For claim 1, we expect the following elements. 

- a device, and some limitation making the device wearable on skin. 

- a flexible substrate.

It's debatable if flexible should limit the substrate, or perhaps the device itself. We’ve opted for the former, but I could imagine claiming a flexible device instead.

-  the first and second sheet.

 The sheets should be electrically conducting and attached to the substrate. Also the substrate should isolate the sheets from each other. One can can quibble whether the latter is enough, I could imagine claiming that the sheets are electrically isolated from each other as well. 

- a triboelectric material, and some limitation to indicate its function in the device.

 The location of the triboelectric material should not be limited to the ends of the sheets.

- a first electrode (4a) and a second electrode (4b), the gap between, and some indication of their relationship with the rest of the components.

 A disadvantage of this wording is that it may seem that electrode and sheet are sperate elements, even though they could be aspects of the same thing. Another wording could avoid this impression, but it would hurt the clarity. We don’t expect this to be needed.

A bit of care is required for claiming the gap, since Document D2 also shows a gap (8), where an electric field will form. If you’re not careful you might have a non-novel claim. We have opted for a functional limitation to distinguish from D2, as this gives a clear and broad claim, while still distinguishing from D2. In our claim the electric field should be applied to the skin, which D2 doesn't do. It is not necessarily impossible to claim this aspect structurally, but the paper gives little guidance towards a good wording for this. So we expect the functional approach to be expected.

As to the dependent claims, we’d expect the two main embodiment types (plaster and bandage) to get a claim. For the bandage it seems worthwhile to claim the position of the sheets with respect to the substrate as this is  quite different than in D1/D2, and thus a strong fallback. 

Details that we picked out for dependent claims further include the position of the triboelectric material, the folding of the sheets, and the use of wires. Note that we have embodiments with 1 and with 2 wires. We’ve opted for an and/or claim to cover this, but one could avoid an or-claim using ‘as least one of’.

For the materials, we invested four of our 15 claims. Although 3 materials are mentioned for the sheet and 3 materials for the triboelectric material, we’ve claimed only 2 of each. The reason being that only 2 materials seem to work well. Finally, there is one combination that is best. This follows from the table as well as from the description. For the electrodes we also have an advantageous material, an antibacterial composition.

There are two applications for the device: medical and non-medical. A method claim for the medical application is not possible, so we’ve added this as a limitation in a device claim. For the non-medical application, we added a method claim, though a use claim would also be possible. Note that the claims should be limited to intact skin, otherwise you’d get a medical effect as a side effect.

Claim 1. A device (14), which is wearable on the skin, the device comprising

-            a flexible substrate (1),

-            a first sheet (2a) and a second sheet (2b), both attached to the substrate (1), the first sheet and the second sheet being both electric conductors, the substrate electrically insulating the first and second sheet,

-            a triboelectric material (15) attached to a part (3b) of the second sheet (2b), a part (3a) of the first sheet overlaying the triboelectric material (15) and being arranged to adhere to and separate from said material (15) when the substrate (1) is deformed causing a voltage to appear between the first and second sheets (2a, 2b), and

-            a first electrode (4a) and a second electrode (4b) forming a gap (8) between them, the first electrode (4a) and the second electrode (4b) being electrically connected respectively to the first sheet (2a) and the second sheet (2b), the first electrode (4a) and the second electrode (4b) being arranged to apply an electric field to the skin (11) when the device is worn on the skin at the gap.

Claim 2. A device as in Claim 1, having the shape of a plaster.

Claim 3. A device as in Claim 1, having the shape of a bandage.

Claim 4. A device as in Claim 3, the first sheet (2a) and the second sheet (2b) being attached to opposite faces of the substrate (1).

Claim 5. A device as in any of the preceding claims, wherein the part (3b) of the second sheet is an end of the second sheet, and/or wherein the part (3a) of the first sheet is an end of the first sheet.

Claim 6. A device as in any of the preceding claims, wherein the first electrode (4a) and/or the second electrode (4b) are electrically connected respectively to the first sheet (2a) and the second sheet (2b) via an electrical wire (5a, 5b) extending through the substrate (1).

Claim 7. A device as in any of the preceding claims, wherein the first sheet (2a) and the second sheet (2b) are attached to a top face of the substrate and fold around the substrate extending along a bottom face of the substrate (1), the ends of the first sheet (2a) on the bottom face forming the first electrode (4a) and the second electrode (4b).

Claim 8. A device as in any of the preceding claims, wherein the triboelectric material is polytetrafluoroethylene (Teflon) or poly (4,4'-oxydiphenylene-pyromellitimide) (Kapton).

Claim 9. A device as in any of the preceding claims, wherein the first sheet and the second sheet are copper or zinc.

Claim 10. A device as in any of the preceding claims, wherein the triboelectric material is Kapton and the first sheet and the second sheet are copper.

Claim 11. A device as in any of the preceding claims, wherein the first electrode and the second electrode are silver.

Claim 12. A device as in any of the preceding claims, wherein the first and second electrodes are coated with an antibacterial composition.

Claim 13. A device as in any of the preceding claims, wherein the first and second electrodes are interdigitated.

Claim 14. A device as in any of the preceding claims for treating a wound.

Claim 15. A cosmetic method of smoothing skin wrinkles, comprising

-            wearing a device according to any of the preceding claims on intact wrinkled skin.

We look forward to your comments!

Sander, Roel, Jelle

 (c) DeltaPatents

Annex  - the complete paper - copied from Wiseflow "EPO – EQE Compendium"

NB: when copying, the line numbering got lost. Please click on the figures for a full-size view.

Client‘s letter 

Dear Ms Vande,

[001] Our company sells healthcare devices to doctors and the general public. We are
specialised in wearable devices for treating skin wounds and other skin problems.

[002] It is known that the application of an electric field to a skin wound accelerates its
healing. When an electric field is applied to a skin wound, cell regrowth is stimulated and
necrotic tissue is destroyed. On the basis of this finding, we developed and sold for
several years a special plaster (see our granted patent D1 in attachment) containing a
battery and capable of applying an electric field to the skin.

[003] The device of D1 is effective, yet it presents problems in so far as the battery can
fall off if the plaster becomes deformed due to body movement. Furthermore, the battery
makes the plaster bulky and difficult to use on curved skin surfaces. We wish to patent a
new device wearable on the skin which does not rely on a battery for applying an electric
field to the skin and thus overcomes these issues. We came up with the idea of
exploiting the deformations of the plaster to generate the electric field.

[004] The invention is based on the well-known "triboelectric effect", according to which
electricity is generated upon friction between two objects. Fig. 1(a) shows a typical
arrangement for obtaining the triboelectric effect. It comprises a first copper sheet 2a,
which is electrically conductive, and a layer 15 of Teflon (trade name of
polytetrafluoroethylene or PTFE), which is electrically insulating and has a tendency to
capture electrons. The Teflon layer 15 is attached to a second copper sheet 2b. The
triboelectric effect occurs when a mechanical action makes the first copper sheet 2a
adhere to and separate from the Teflon layer 15. In the adhesion phase (Fig. 1(b)),
electrons from the surface of the first copper sheet 2a are captured by the surface of
Teflon layer 15. In the separation phase (Fig. 1(c)), the electrons remain attached to the
Teflon layer 15. Therefore, the first copper sheet 2a and the Teflon layer 15 respectively
acquire positive (+) and negative (-) electrical charges. As a result, a voltage appears
between the copper sheets 2a, 2b as if a battery were present.

[005] The attached publication D2 shows an example of a wearable device using the
triboelectric effect for sensing muscular activity. The device of D2 is quite bulky however
and still requires a battery.

[006] In summary, the triboelectric effect transforms a mechanical action into a voltage,
which in turn generates an electric field. Surprisingly, we found that the triboelectric
effect induced in a wearable device by movement of the body wearing the device can
generate an electric field sufficient for healing wounds without requiring a battery.

[007] Fig. 2(a) shows schematically in cross-section a first example of our invention. This
device 14, which is wearable on the skin, has the shape of a plaster and includes a
substrate 1 made of PET, a first copper sheet 2a and a second copper sheet 2b, both
attached to the top face of the substrate 1. A Teflon layer 15 is attached to one end 3b of
the second copper sheet 2b. The first copper sheet 2a comprises one end 3a, which is
not fixed to the substrate 1. The end 3a overlays the Teflon layer 15 and is able to
adhere to and separate from said layer 15 when the substrate 1 is deformed. As in the
product of D1, the bottom face of the substrate 1 comprises two copper layers 4a, 4b
acting as first and second electrodes and forming a gap 8. The first electrode 4a and the
second electrode 4b are electrically connected respectively to the first copper sheet 2a
and the second copper sheet 2b via electrical wires 5a and 5b extending through the
substrate 1. Adhesive layers 7 are also provided underneath the substrate 1.

[008] In use (Fig. 2(b)), the plaster 14 is attached to the skin 11 by the adhesive layers 7
so that the wound 13 is located in proximity to the gap 8. The plaster 14 is flexible and
deforms through movement of the body or muscle contractions, as schematically
indicated by the arrows in Fig. 2(b). Upon deformation of the substrate 1, the end 3a of
the first copper sheet 2a adheres to and separates from the Teflon layer 15. By means of
the triboelectric effect, the first copper sheet 2a becomes electrically charged. A voltage
appears between the first and second copper sheets 2a, 2b and, due to the electrical
connection, also between the first and second electrodes 4a and 4b. Consequently, an
electric field E (dashed lines) is generated in the gap 8. Therefore, when the plaster 14
is worn on the skin 11, the electrodes 4a, 4b are arranged so as to apply the electric field
E to the skin.

[009] In principle, any pair of electrically conductive elements separated by a gap
functions as electrodes generating an electrical field in the gap when subject to a
voltage. Therefore, we have devised another example of the invention shown
schematically in Fig. 3. In this device 16, which is also wearable on the skin, the first and
second copper sheets 2a, 2b are folded around the substrate 1 and extend along the
bottom face of the substrate 1 forming the gap 8. The electrodes 4a, 4b are formed by
the ends of the copper sheets 2a, 2b at the gap 8, which are therefore arranged so as to
apply an electric field to the skin as in the previous example. The necessary electrical
connection between each of the electrodes 4a, 4b and the respective copper sheets 2a,
2b is provided by the copper sheets themselves: no wires are needed.

[010] A third example of our invention, schematically shown in cross-section by Fig. 4, is
a device 17, wearable on the skin, having the shape of a bandage and particularly suited
for wounds on body parts such as arms, wrists or legs. The shape and the flexibility of
the bandage 17 allow it to be held in place around these body parts by elastic force
without adhesives. In this example, the substrate 1 is a strip of PET bent into a closed
shape, e.g. to form a circle. A first copper sheet 2a is attached to an inner face of the
substrate 1 and a second copper sheet 2b is attached to an outer face of the substrate.
A Teflon layer 15 is attached to one end 3b of the second copper sheet 2b. The first
copper sheet 2a and the second copper sheet 2b are thus attached to opposite faces of
the substrate 1, wherein the substrate is bent so that one end 3a of the first copper
sheet 2a overlays the Teflon layer 15. Upon deformation of the substrate, this end 3a of
the first copper sheet 2a adheres to and separates from the Teflon layer 15. The other
end of the first copper sheet 2a acts as the first electrode 4a. The second electrode 4b is
provided as a copper layer on the inner face of the substrate 1 and is electrically
connected to the second copper sheet 2b via the wires 5. The first and second
electrodes 4a, 4b form the gap 8.

[011] In use, the bandage 17 is applied, e.g. around the wounded arm, so that the
wound is located in proximity to the gap 8. Muscle contractions of the arm cause the
substrate 1 to deform. Upon deformation of the substrate 1, the end 3a of the first
copper sheet 2a adheres to and separates from the Teflon layer 15. Due to the
triboelectric effect, as in the previous examples, an electric field E (dashed lines) is
generated in the gap 8 between the electrodes 4a, 4b. Therefore, when the bandage 17
is worn on the skin, the electrodes 4a, 4b are arranged so as to apply the electric field E
to the skin.

[012] In slight modifications of the examples shown above, it is not one end 3a of the
first copper sheet 2a that adheres to and separates from the Teflon layer 15 but another
part of the first copper sheet 2a. Similarly, the Teflon layer 15 may be attached to other
parts of the second copper sheet 2b as long as the first copper sheet 2a is able to
adhere to and separate from the Teflon layer 15 upon deformation of the substrate 1.
The devices of our invention may be made in shapes other than a plaster or a bandage
provided that they are wearable on the skin.

[013] Instead of PET, other materials are suitable for the substrate 1 as long as the
substrate is flexible and electrically insulating so as to avoid a short circuit between the
first and second copper sheets 2a, 2b. These sheets 2a, 2b may be made of other
electrically conductive materials, e.g. of aluminium or other metals but, for reasons of
compactness and flexibility, must be in the form of sheets. Teflon is a known triboelectric
material. Other known triboelectric materials suitable for the layer 15 are Kapton (trade
name of poly (4,4'-oxydiphenylene-pyromellitimide)) and polydimethylsiloxane (PDMS).
The electrodes 4a, 4b may be made of the same electrically conductive material as the
sheets 2a, 2b or of a different electrically conductive material.

[014] We tested the device of Fig. 2(a) with different choices of materials. The time for
healing a wound was found to depend on the choice of the materials for the triboelectric
layer 15 and for the electrically conductive sheets 2a,2b, as reported in the following
table: [NB: formatting got lost when copying, I tried to reconstruct it]

               Copper           Aluminium       Zinc
Teflon     48 hours        120 hours        72 hours
Kapton    49 hours        100 hours        66 hours
PDMS     95 hours        150 hours        110 hours

Similar results are also expected with the other examples of our invention. Without
application of the device, the wound took approximately 200 hours to heal. The best
results were obtained with Teflon or Kapton and with copper or zinc. A particularly
advantageous combination was found in Kapton and copper. We have further tested
electrodes made of a silver layer, whose antibacterial properties provided a further
improvement. It is furthermore possible to coat the electrodes with an antibacterial
composition.

[015] The devices of our invention have proven effective not only for healing wounds but
also for smoothing skin wrinkles, for which the effect of an electric field is known. In this
cosmetic use, a device of our invention is worn on intact wrinkled skin. When worn on
intact wrinkled skin, the device has no therapeutic effect but only the cosmetic effect of
smoothing out the wrinkles. Especially for this use, it is advantageous to apply the
electric field to a relatively large area of the skin. For this purpose, the invention may
include electrodes having the shape shown in Fig. 5 (view from above), which are known
in the art as "inter-digitated electrodes". These electrodes have a gap 8 extending over a
large area and thus provide the desired effect.

 [016] Please draft a set of claims and an introductory part of the description for a
European patent application to protect our invention, also with regard to its uses. It
should be assumed that the drawings accompanying this letter will form part of the
application. Unfortunately, we have no financial budget for claims fees or for further
patent applications.

Best regards,

Dr Graaff

Document D1: EP11071982 - Electric plaster

[001] The present invention, shown schematically in Fig. 1, is a device 18 wearable on
the skin, having the shape of a plaster and capable of applying an electric field to a skin
wound for accelerating the healing of the wound. It comprises a substrate 1 of PET, a
flexible and electrically insulating material, a first copper sheet 2a and a second copper
sheet 2b, both attached to a top face of the substrate 1. One end 3a of the first copper
sheet 2a is not fixed to the substrate 1 so that a button-shaped battery 6 can be held in a
space between the two copper sheets by the elastic force of the first copper sheet 2a.
The bottom face of the substrate 1 comprises two copper layers 4a, 4b acting as first
and second electrodes and forming a gap 8. The first and second electrodes 4a, 4b are
electrically connected respectively to the first and second copper sheets 2a, 2b via
wires 5a, 5b extending through the substrate 1. When the battery 6 is inserted, the
voltage of the battery is applied across the copper sheets 2a, 2b and, via the electrical
connection, also across the electrodes 4a and 4b. When the voltage of the battery is
applied across the electrodes 4a, 4b, an electric field E (dashed lines) is generated in
the gap 8. Adhesive layers 7 are also provided underneath the substrate 1.

[002] In use (see Fig. 2), the device 18 of the invention is attached to the wounded
skin 11 by the adhesive layers 7 so that the wound 13 is located in proximity to the
gap 8. Therefore, when the device 18 is worn on the skin 11, the electrodes 4a, 4b are
arranged so as to apply an electric field E (dashed lines) to the skin. This electrical field
accelerates the healing of the wound 13.

[003] Claim
1. A device (18) wearable on the skin and having the shape of a plaster, comprising:
a substrate (1) made of PET,
first (2a) and second (2b) copper sheets attached to the top face of the substrate (1) so
that a battery (6) can be held in a space between the first (2a) and second (2b) copper
sheets, characterised by:
first (4a) and second (4b) electrodes made of copper layers, electrically connected
respectively to the first (2a) and second (2b) copper sheets by wires (5a, 5b), and
arranged so as to apply an electric field to the skin (11) when the device is worn on the
skin.

Lignin: [008] is somewhat ambiguous of whether it is inherent to raw plant material that it does not comprise lignin, or whether the invention uses raw plant material which specifically does not contain lignin (i.e., a specific type of raw plant material). In case of the latter interpretation, "does not contain lignin" should be added as an additional limitation to the method claim, i.e., "providing raw plant material, wherein the raw plant material does not contain lignin".

[NB: according to the model solution, it was indeed expected to include the limitation that the raw plant material does not contain lignin.]

Paper sheet: The paper sheet of the client containing pure cellulose fibres homogeneously intermixed with glue is already novel over D1 and D2 as both use sizing, which according to [016] of the client's application refers to the applying of a coating of glue. In D1 and D2's paper sheets, the glue is thus non-homogeneous intermixed with the pure cellulose fibres but applied as a coating. It therefore does not seem necessary to add further limitations to the paper sheet, such as the tensile strength.

[NB: in the model solution, the tensile strength is also included in the claim.]

Displacement/viscosity: According to the client's letter, enhanced pulp circulation is essential to achieve the desired paper strength and surface quality, see [023]. The enhanced pulp circulation is defined in terms of over 90% displacement of the pulp volume with each stroke of the hammer, and can be verified by taking samples and measuring that their viscosity throughout the vat does not differ by more than 1%.

Does the displacement/viscosity then need to be included in the product claim? The parameters/metrics described in [0023] to quantify sufficient circulation do not seem well suited as apparatus limitations as they refer to the paper pulp and may indeed depend on the characteristics of paper pulp (e.g., its viscosity), while the apparatus should be claimed without the paper pulp. The corresponding apparatus limitation is the slant/head-to-shaft angle, but it's not clear from the exam which angle satisfies the circulation requirements (and most probably slight deviations from 90 degrees will not). However, ultimately, we've chosen not to limit the apparatus claim beyond the non-90 degree angle, as any deviation from 90 degrees (D1) will be novel and have an improved circulation and therefore a positive effect. [NB: this was indeed the expected solution]

For the manufacturing method, it does seem necessary to limit the claim to ensure enhanced pulp circulation, as the method more directly pertains to manufacturing a paper sheet and otherwise the paper sheet does not have the desired strength and surface quality. In other words, we interpret the client's remark on the essentiality of the sufficient circulation as an essential feature on the use of the apparatus rather than on the apparatus itself. To ensure sufficient circulation, just referring to the product does not seem enough because, as mentioned above, it seems unlikely that small deviations from 90 degrees will achieve the intended circulation. So we need to limit the method claim. The question then remains whether to go for the 90% displacement or the 1% viscosity. Both seem reasonable possibilities. The 90% displacement can be nicely formulated as a method step ("comprising displacing over 90% of the pulp volume ..."), but has the disadvantage that according to GL F-IV 4.11 it appears to be necesssary to specify the measurement method (1% viscosity etc) then as well. The viscosity on the other hand is readily measurable, so we have chosen to include this limitation in the claim. [NB: both were accepted according to the model solution.]

Effective circulation: It is evident from the client's description that the glue is only homogenously mixed with the paper pulp during the stamper beating if the circulation is sufficient, see [0023]. However, the parameters/metrics described in [0023] to quantify sufficient circulation do not seem well suited as apparatus limitations as they refer to the paper pulp and may indeed depend on the characteristics of paper pulp (e.g., its viscosity), while the apparatus should be claimed without the paper pulp. The corresponding apparatus limitation is the slant/head-to-shaft angle, but it's not clear from the exam which angle satisfies the circulation requirements (and most probably slight deviations from 90 degrees will not). However, ultimately, we've chosen not to limit the apparatus claim beyond the non-90 degree angle, as any deviation from 90 degrees (D1) will be novel and have an improved circulation and therefore a positive effect. For the manufacturing method, however, it seems (more) essential to have the sufficient circulation, as the method more directly pertains to manufacturing a paper sheet and otherwise the paper sheet does not have the desired strength and surface quality. In other words, we interpret the client's remark on the essentiality of the sufficient circulation as an essential feature on the use of the apparatus rather than on the apparatus itself. As such, we've chosen to limited the method claim. Of the metrics/parameters mentioned in [0023], the viscosity is readily measurable so seemingly a good parameter; for the displacement-volume, it is not clear how that can be measured/if it is objectively measurable, so this metric/parameter seems less suitable.

[NB: according to the model solution, both viscosity and displacement volume could be used. The model solution also considers it unnecessary to refer back to the product claim.]

Other claim categories: in addition to the categories above, one could consider a claim on the paper pulp itself comprising pure cellulose fibres homogeneously intermixed with glue. We didn't add this claim for the mere reasons of the 15 claim limit and while a method of manufacturing pulp is suggested by the client ([009], first sentence), the pulp itself is not. 

[NB: this claim was included in the model solution..]

• The paper
• Our first attempt at the claims

• You can open multiple tabs with the paper (Assignment), so this may help in simultaneously navigating within different sections, e.g., tab-1: clients letter, tab-2: D1, tab-3: D2
• Use a small size font for typing in your answer, this helps in keeping an organized view in the editor
• By using the various "header" styles of the editor, a table of contents is automatically created; however, it seems that jumping between various sections created by these headers does not work for everyone
• Don't waste time on building an overview of all features - effects - fallback positions in the editor. We still recommend organizing all information from the client's letter and the prior art on paper - as you would have done for the all-paper exam. The search option within the PDF browser may facilitate checking for features  - including any indications of essential features ("must", "essential", "required" etc.) and advantages.

Please share your experiences with the platform, as well as any comments to the paper.

• the clients letter is only available online (pdf); the clients letter can not be printed;
• the drawings of clients letter are available for printing in advance (as well as in the pdf during the exam)
• the prior art is available for printing in advance (as well as in the pdf during the exam)

• irradiating a glass pane with a laser beam to create a protrusion at a first location on the surface of the glass pane facing the laser, 
• solidifying the protrusion by terminating the irradiation, and 
• repeating the irradiation and solidification at at least one location, different from the first location, on the surface of the glass pane facing the laser.