An Easy Releasable, Perforated Elastomer Membrane for

Epidermal Electronic DevicesHubert Denis, Bikram K. Mahajan, Avinash Kankipati, Dr. Xian Huang

Missouri University of Science and Technology

Mechanical and Aerospace Engineering Department

Epidermal electronic devices can be mounted directly on human or animal

skin like temporary tattoos, and have the potential to revolutionize health

and wellness monitoring techniques. These devices typically contain

elastomer membranes as backing layers to protect the electronic devices

from external scratching, while providing adhesion force to allow the

devices to stay on skin. However, the majority of the epidermal electronic

devices are attached to the skin using a releasing or transfer printing

process that involves the use of water soluble tape, which is inconvenient

and tedious to remove. Here, we develop an improved method using a

releasing film for the elastomer membranes and silicone adhesive for

better skin attachment. The releasing energy of individual interfaces of

these stacked layers (releasing film, oil film, elastomer membrane, and

silicone adhesive) were studied and measured using a tensile test

machine to determine the optimum combination of membrane materials

that will lead to easy membrane releasing on skin.

Additionally, a 3D printed micro needle array is used as a mold to

perforate the elastomer membrane to allow the water vapor from the skin

to escape, allowing the membrane to stay on skin for periods up to a

month.

• Find appropriate lubricant to facilitate the peeling of the releasing

tape.

• Design aesthetics for the releasing tape to ease the peeling.

• Design models to determine the peel force between the releasing

tape and the Dragon skin (with the lubricant), silicone adhesive and

the skin.

• Build the backing layers for practical tests.

• Composition of edible oil such as coconut oil and olive oil in a comparison

table

• Theory behind the peel force and the adhesion force

Rivlin equation states that:𝑭

𝒃=

𝑮

𝟏−𝒄𝒐𝒔𝜽

where F is the peel force, b the film width, G the adhesion energy, and θ the

peel angle between the film and the substrate.

• From the peel test we can conclude that the olive oil remains the best buffer.

• The chronological study of the membrane over the skin infers that the perforated

membrane stays over a longer time.

• Next, the peel force between a dummy skin and the silicone adhesive will be

determined so that the force between the adhesive and the skin remains bigger

than that of the force between the releasing tape and the silicon layer.

• The epidermal electronic device will then be embedded on the backing membrane

for health and wellness monitoring.

• The peel rate in all cases: 30 mm/min.

• The maximum peel force obtained for no oil, coconut oil, and olive oil samples,

is 15 N, 5.4 N, and 3.2 N respectively.

• The average load obtained for no oil, coconut oil, and olive oil is 10.097 N,

3.636 N, and 1.441 N respectively.

• Calculating the adhesion energy using rivlin equation at 1800in each case, we

get 448.76 J, 161.6 J, and 64.04 J respectively.

Elastomer Membrane

Elastomer membrane layers – side view

Oil typeViscosity

(poise)

Volume flow rate

(𝒄𝒎𝟑/sec)

Surface tension

(dyne/cm)

Coconut oil 0.229 7.76× 10−3 17.84

Olive oil 0.437 10.00× 10−3 10.00

Comparison table of two edible oils

• The use of Dragon skin series 10 slow(Silicone) and Silbione RT Gel

4317 A&B (Silicone adhesive).

Peel Test Model

Layers stacked in a petri dish

Aesthetics

Plain film

Cut film Diagonally cut film

Position vs Load graphs for samples with No Oil, Coconut oil and Olive Oil

60 mm

45

mm

ABSTRACT

0 20 40 60 80 100 120 1400.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

Lo

ad

(N

)

Position(mm)

Olive Oil

0 20 40 60 80 1004

6

8

10

12

14

16

Lo

ad

(N

)

Position (mm)

No Oil

0 20 40 60 80

0

1

2

3

4

5

6

7

Lo

ad

(N

)

Position (mm)

Coconut Oil

Petri

Dish

Releasing

Film

This Research is supported by the National Science Foundation (NSF), Research

Experience for Undergraduates (REU) in Missouri S&T and the start-up funding from

Dr. Huang.

Releasing Tape Film

Electronic Device

Sweat Sensor RF Energy Harvester Hydration Sensor

Silicon Dioxide (Si𝑶𝟐)

Electronic Device

Silicon Dioxide (Si𝑶𝟐)

Silicone Layer

Water Soluble Tape

Epidermal device layers

Peel Test

Lower

clamp

Upper

clamp

Backing

layer

Releasing

film

1800 Peel test for a sample

under an UTM

Epidermal Electronic Devices

BACKGROUND

GOALS

PROCEDURES

CONCLUSION

ACKNOWLEDGEMENT

Lubricant Layer

Silicone Layer

Silicone Adhesive LayerTime

Elapsed

1 Hour view 2 Hour view 3 Hour view 4 Hour view 5 Hour view 6 Hour view 7 Hour view 8 Hour view

Membrane

Perforated

Membrane

Non

Perforated

• A chronological study has been done by placing both perforated and non-perforated

membranes on to the skin and observed for 8 hours.

• The membrane which has been perforated was observed to stay long on to the skin.

• The membrane which is not been perforated had the more tendency to loose the

adhesive due to the accumulation of sweat.

• We observed that the non-perforated edges have been rolled out after 8 hours.

Device backing membrane skin life span monitoring

3D micro needle array perforator

RESULTS & DISCUSSION