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Herald Angel Noujoum: Hello and 
welcome to our next talk,

Why 3D printing clothes is NOT the future. 
Short question to the audience:

Who of you has already 3D printed anything? 
Please raise your hand.

That's what I thought, I estimate that's about 
80 % of the audience in this hall.

I am not surprised, it is the topic of this talk, 
that's why you are here.

Second question: Who of you

has already tried 3D printing clothes?
Please raise your hand again.

I see four people.
So, how did it go?

One person indicates 
that it worked out well,

the others are showing hand gestures 
of "not that well".

Who of all the people that have 
already 3D printed

has thought about printing clothes?

Ok, about 10 people have thought 
about that.

Our next speaker, Rebekka, will tell you 
why it might not be the best idea

to 3D print clothes. 
On the internet

and especially Twitter, Rebekka is known
by her nickname Kurfuerstin

and she is a clothing technician. Her 
research includes

traditional apparel production, she has 
worked in a fashion company,

at the theater and at a tv show.

Also, she is researching innovative 
techniques such as 3D printing

and virtual clothing simulation,

meaning software that realistically 
simulates clothes

on a virtual avatar.

Have fun with the talk , 
I hope you will learn a lot

and please welcome Rebekka

with a round of applause. 
Thank you.

<i>applause</i>

Speaker Rebekka/Kurfuerstin: I just 
received some mail really quick,

but that won't stop me from giving 
my talk. Welcome,

nice to see you all here, in this hall 
and on the live stream and...

additional mail, okay, a lot happening 
on this stage. I will maybe read that later,

but it is great to know that the 
post office system works!

The title of my talk is "Why 3D printing 
clothes is NOT the future".

It will be about the properties of 
3D printed clothes and

what would need to happen in order 
for it to be a serious alternative

for everyday wear. I was just introduced 
as a clothing technician.

In case you don't know what this strange 
combination of words means,

clothes and technology, 
a short explanation.

When clothes are made, at one side,

you have the design, the idea.
But the realization, the production,

happens somewhere else entirely
and by some other person.

In a simplified way, a person creates 
the design for a dress

and says: I designed this dress.

So they have a nice picture from which 
you can learn some information, but not much.

And they go to a factory and say: 
please make this dress.

The production will kindly ask: 
where is the table of information?

Because the production site wants to 
have all the information about the dress.

And the designer then asks: what? 
And the production then asks: what?

And that would be the end of it.

Because the factory wants to know, 
which fabric do we need for the dress,

and how much? Which sizes will be made, 
and how many dresses in which sizes?

Which machines do we need for that, what 
text will be on the care instruction labels

and what will be the exact position of the 
labels on the side seam in cm?

All those questions cannot be answered 
by the illustration of the dress.

And that is where clothing technology comes in,
as the intersection between design and production.

It's about the technical feasibility and

what needs to be done 
to manufacture clothes.

It's about materials, quality, 
prices and locations.

Where should the production take place, 
and when?

All these questions need answers 
and that is the responsibility

of clothing technicians. 
And this kind of reality check,

the perspective of feasibility, is the perspective 
I also chose to examine 3D printing.

If you search for the words "3D print" and 
"clothes", you will get headlines like these.

For example: 3D printing will bring 
flexibility into the fashion industry.

Or: The fashion of the future. Or: Will the 
street wear of the future be 3D printed?

Or: Can 3D printing fundamentally 
change the fashion industry?

A few years ago, the headlines were 
even more sensational.

They were predicting that by 2020, we 
would print a sweater in the morning,

melt it down in the evening and then 
print a new one the next day.

Nowadays, the predictions have 
become a bit more careful,

at least with a question mark at the end.

But even from these headlines, 
you get the sense that something

will fundamentally change the 
fashion industry.

There is also the hope of 
a sustainable production

with the argument, that the procedure 
of 3D printing is sustainable.

Sustainability is a major topic 
in the fashion industry.

The question is if 3D printing 
might be the solution.

Clothes have already been 3D printed,

it's not even that new or unrealistic.

There are entire 3D printed collections and 
I will show some examples now.

In Israel, Danit Peleg printed her entire 
final collection of five outfits.

In Israel, Danit Peleg printed her entire 
final collection of five outfits.

One example is the two piece outfit on
the right, a top and a floor length skirt.

The skirt has been printed using 
only desktop printers,

meaning that it consists of 
modules of A4 size

that have been connected afterwards.

It is flexibel, because it was printed 
with a flexible filament,

but also because it made up 
of a zigzag structure

that allows for it to pull on it.

If you pull it up, it bounces up and down.

The jacket is the first 
3D printed ready-to-wear

article of clothing that 
you can order online,

in limited edition of 100 pieces.

It costs 1500 $.

You can choose the color and 
some writing on the back

and then the jacket will be 
printed in 100 hours.

Another example is from the 
design collective Nervous System,

who have developed the Kinematics System.

It consists of triangles 
that are connected by hinges,

making the whole structure flexible.

But it is made of a hard material. 
It can move, but it is not elastic

and it rattles a bit when you move.
They also developed an opaque version.

The dress on the right is based
on the same triangle structure,

but there are some kind of 
petals on top of it.

So the dress is opaque.

A third example is the Pangolin Dress

which is also made of a structure 
of interlocked modules

that can move on top of 
and into each other,

thus making the structure flexible.

You can move in the dress and the 
dress adjusts to your movements.

One of the people working on it is 
Travis Fitch, a designer working in New York.

I contacted Travis and said: I am a 
clothing technician, I love numbers.

How do you know if a newly developed 
structure is suitable for a dress?

How do you know if the elasticity 
is high enough

to use it in a piece of clothing?

Do you do laboratory tests?

And he answered, well, I pull at it and then 
I either say it is okay or not.

So the clothing technician in me 
came through and said,

well how about numbers? So I offered 
to test some of his structures,

to conduct some laboratory experiments

in order to examine how the properties 
can be expressed in numbers and units.

Those were only three examples. 
There are many more

on catwalks and in fashion shows. It is clear 
that those examples are not everyday wear.

They are special made-to-order products,

it takes months to create them,

they consist of 300 different pieces 
that need to be assembled.

But the headlines about fundamentally 
changing the fashion industry

are about everyday wear.

Custom-made items on a catwalk 
do not change the whole industry.

Something needs to happen 
before that applies to everyday wear.

That is why I ask, what kind of properties 
do clothes need to have

in order to be everyday wear, 
meaning clothes

that we can wear every day and 
for every occasion?

First of all, clothes need 
to be comfortable.

There are four aspects of wearing comfort.

First, the psychological wearing comfort 
which is about fashion trends,

societal norms and individuality.

The fact that I am standing here 
in a t-shirt and a hoodie

is particularly apt for this congress.

On another business conference I might 
have worn something different.

And that people are driving around 
in onesies and goose costumes

is also very specific for this group right here.
<i>laughter</i>

What I mean by this is that people feel 
comfortable wearing this in this specific context

and might not feel at ease 
in another context,

although the clothes themselves 
have not changed.

That is the psychological wearing comfort.

The next-to-skin-comfort is about 
the feeling of something on the skin.

Surfaces can be soft or scratchy, 
they can also cause allergies.

So it is about the direct contact 
on the skin.

The physiological wearing comfort is very 
important as well. It's about the climate control

of the body and about how clothes can keep 
us warm but also allow for moisture to evaporate.

The human body has this amazing system 
of protecting us from overheating.

We start to sweat and 
the moisture evaporates.

But the evaporation has to happen 
through the fabric of our clothes.

Some clothes allow for better evaporation 
than others.

This aspect is incredibly important for our 
comfort when wearing clothes.

The fourth aspect is the 
ergonomical wearing comfort

which is about freedom of movement 
and that is what I examined in detail.

Freedom of movement in clothes is 
achieved by the fit of a piece of clothing,

mainly meaning how tight it is on the body.

Secondly, it is achieved by the elasticity 
of the materials used.

This is very important because there are parts 
of our body where we need 50% stretching,

for example at our knees and elbows.

If you move your arm like this, then the 
clothes need to allow this movement

without tearing apart.

Without elasticity, 
the sleeve would be destroyed

or would change its form and create buckles.

If we have a very tight sleeve

made from a material that is not elastic

the sleeve at the elbow would take 
the shape of our elbow.

So we need a material with 
the capability to rebound.

After we have moved the arm like this, 
the sleeve at the elbow

will go back to its original shape.

So if a material is not elastic, 
it is not that suitable for clothes.

It is possible, but then it needs to be 
compensated by the cut of the clothes,

in that case, it cannot be too tight. 
If a piece of clothing is loose fit,

the elasticity of the fabric 
is not that important.

I wanted to examine the influencing 
factors on the elastic properties

of 3D printed structures in order 
to actively influence the elasticity.

This could be used

to enhance the wearing comfort 
of 3D printed clothes

and thereby get us a bit closer to 
3D printed everyday wear.

Elasticity in textile structures, fabrics, 
is achieved by two aspects.

First, a material itself can be elastic.

In fabrics, this is mostly elastane.

Elastane can be stretched 300% 
and will return to its original length.

It is used in a majority of clothes,

mostly in the ratio 98% cotton and 2% elastane.

2% are enough to make a shirt 
elastic enough to easily put it on

while at the same time being tight 
and not starting to buckle after wearing.

The second possibility is structural elasticity.

In clothing, this is mainly achieved 
by creating knitwear.

If you pull at knitwear,

the loops will change their shape.

In this manner, 
you can create an elastic structure,

even with materials with low elasticity.

For example, cotton fibers are 
not very elastic. But if you create a knitwear

made of cotton threads, 
the fabric can be very flexible and elastic.

In 3D printed structures,

an elastic material can be used as well, 
for example TPU.

TPU is short for thermoplastic polyurethane. 
Polyurethane is a primary part of elastane, too.

So TPU and elastane have very similar 
properties based on their chemical composition.

Structural elasticity is also possible.

It is possible to print meshes,

but you can also create different shapes
like curves, arches, helices or springs.

In short, shapes that you can 
compress or pull at,

so that you will first pull at the structure 
before pulling at the material itself.

However, the design depends 
on the printing method. There are several

different methods and not all of them are 
equally suited to create certain shapes.

For my research, I focused on two of them.

First, the FLM, 
short for fused layer modeling,

sometimes also called FDM, 
short for fused deposition modeling.

You heat a thermoplastic filament

and push it through a nozzle

The nozzle then lays the strand of material 
on the printing bed.

All layers on top of each other 
make the object.

If an object has an overhang 
like the shape on the left,

you need support structures.

In every layer, the extruder will also 
build the supporting columns.

When the object is finished,

the support structures can be removed.

This is not a problem for hard materials,

you can easily break it off 
and sand the surface.

But for elastic materials, 
it's a different situation.

If you pull at it, it will not break off, 
but simply stretch.

So if you want to print elastic shapes 
with overhangs or interlockings,

this method is not recommended.

The support structures 
cannot be broken off,

they would have to be cut off 
with scissors,

so that would take a long time.

Interjection: Water soluble support structures!

Speaker: Yes, good idea, unfortunately 
that does not work for TPU yet.

Waterbased support structures 
are usually made of PVA.

you can remove them with water afterwards.

But the melting temperatures 
of PVA and TPU do not match.

TPU requires a very high temperature, 
I printed with 215°C.

At this temeprature, PVA is already decomposing, 
its melting temperature is lower.

So it is a good idea, but at the moment 
it does not work yet.

I am sure that something will be developed

to solve this problem, though.

The other method is SLS, 
short for selective laser sintering.

An entire layer of powder is laid 
on the build plate.

A laser melts the fine grain powder in order

to create the desired shape layer by layer.
In this case,

the powder itself is the support structure, 
so you do not need to print

supporting columns. In the end, the entire 
printer is filled with a block of powder

and somewhere in there,
the object can be found.

The powder is removed and can be reused.

For my research, 
I examined several structures.

The ones on the left and in the middle 
are created from powder.

So it was possible to create some height 
and chain-like shapes.

I had different sizes.

The smaller size is much more flexible,

you can easily move it and fold it.

The modules can be shifted 
into each other.

You can compress it and pull at it 
and the structure is very flexible.

As I said, for the other 3D printing method, 
the possibilities in shape were limited.

This structure is based on a pattern of rhombs 
that was extruded.

If you pull at it, the shape 
of the rhomb changes

before the material itself is strained.

Again, I had different variations in size and height

in order to examine the influencing factors 
on the elastic properties.

in order to examine the influencing factors 
on the elastic properties.

How can you examine 
elastic properties at all?

How can you examine 
elastic properties at all?

With a so-called tensile test.

You don't test a piece of clothing, 
you only test a fabric swatch.

The swatch is clamped into a tensile test machine 
which then pulls with constant velocity.

The corresponding software automatically 
creates a diagram like the one on the right.

It shows the elongation in %,

meaning how long the fabric swatch 
has been stretched,

and on the other axis 
the tensile strength in N,

how much strength is needed in order to 
achieve this elongation of the fabric swatch.

This diagram shows the elongation, 
the elasticity and the tensile strength.

I need to stress that elongation and 
elasticity is not the same.

You can stretch something and it 
might have just gotten longer.

If I stretch something

and it returns to its original length, 
it is elastic.

So that is a different property,

which you can also gather 
from the stress-elongation-diagram.

I tested all of my structures this way.

Of course, you need to test several specimen 
in order to generate average values.

So I had my numbers and units.

But what do I do with that?

I still need to know if these numbers are 
good or bad. There is a recommendation

by the Dialog Textil Bekleidung in cooperation 
with the German Fashion Mode Verband,

It is not a standard or a law, 
clothes do not have to have these properties.

But it is a recommendation, what stretch properties 
clothing should approximately have

and what kind of forces 
they should withstand.

This is a small extract. 
It is divided by products,

so trousers and skirts have different 
specifications opposed to underwear.

If it is far from the body, meaning loose fit, 
lower tensile strengths suffice.

If a piece of clothing is loose fit,

the stretching properties 
are not that important.

So I compared these numbers to mine 
and I found

that the elongations of my structures 
were great.

But the maximum force was not reached.

So I can stretch my structures just fine,

but I do not need a lot of force to tear 
them apart and that is a bad result.

If I bend my elbow 
and the sleeve is destroyed,

I do not want to use this structure 
for clothes.

So the tensile strength of the 
3D printed structures is lower

than the recommended 
properties for clothes.

I also wanted to examine the influencing 
factors on the elastic properties.

From my results, I could see that the size of 
the modules influences the properties.

The larger sizes show higher values 
than the smaller variations.

However, the larger variations do 
not feel and move like fabric.

The smaller variations are 
more fabric-like,

but they didn't show very good 
tensile strengths.

Aside from that, there was another 
influencing factor: the slicing software.

The slicing software has two main tasks.

Firstly, it slices the object into layers. Secondly, 
it transfers the information to the 3D printer,

where the extruder has to be in order to 
create the shape of each layer.

For example, if you want to print a vase 
like the one on the left, the first layer

would be filled completeley, because we want 
to fill the vase with water and it should not leak.

The path of the extruder could look like this, 
it would go in rows

from one side to the other in order to 
completely fill the circle.

The second layer would be a ring 
and the extruder might

take a path like this, but a different 
path is also possible.

There are many different slicing programs 
with many setting options.

I took a closer look and I found 
that the extruder

took a very specific path for 
my rhomb structures.

It went to the intersection and then 
turned around. Under the microscope,

you can see that this is exactly the place 
where the structure was torn apart.

The extruder did not cross the 
intersection even once.

At this point, the strands of material 
are only connected when a new,

hot strand melts a little bit into 
the other, already cold one.

But due to the fact that the extruder 
did not cross the intersection, it created

a predetermined breaking point. That 
is exactly where the structure was torn apart.

In another variation that was based on the 
same shape, the slicing software decided

something else. The extruder took the path 
to the bending point of the rhomb.

Consequently, this is the point 
where it was torn apart.

That is why the test samples look 
differently after the tensile test.

That also explains the low tensile 
strength of the structures.

The tensile test machine did not pull at the 
material as much as at these connection points

and depending on how strong these are,

the structure can be torn apart easily.

This means that the method itself 
limits the tensile strength.

Now, I tested eight different structures,
eight different variations.

You might ask now how I came to the 
conclusion that 3D printing clothes

is not recommended in general.

Maybe a different structure would show 
a higher tensile strength.

Yes, maybe. But the method itself creates 
limitations concerning the properties.

We have to go deeper and look 
at the molecules.

Textile fibers naturally have a 
very high tensile strength.

On the inside, natural fibers like cotton, 
wool or linen show a regular

arrangement of molecular chains.

There are amorphous parts 
and crystalline parts.

The strands that you can see on the 
right depict molecular chains.

The amorphous parts, 
where the molecules are

tangled like a plate of spaghetti, 
are not stable.

The crystalline parts, where they show a 
regular arrangement, are stable.

Natural fibers show a high degree of 
crystalline parts which translates

to a high tensile strength. Fibers naturally 
show higher tensile strengths

than my 3D printed structures 
could ever have.

And for synthetic fibers, there are 
measures we can take to even influence

and increase the tensile strength.

There are several ways to spin a fiber, 
at least one of them is very similar to 3D printing.

You melt synthetic material and press it 
through a nozzle.

The extruded strand is the fiber.

The difference is that you have several 
possibilities to influence the property

of the extruded strand or fiber.

The degree of crystallinity depends on 
the rate of controlled cooling.

The slower a fiber cools off the more 
time do the molecular chains have

to arrange themselves regularly.

That is why the spinning chambers 
are really hot

in order to allow for a very slow rate 
of controlled cooling

so that the fibers show high degrees of 
crystallinity, resulting in high tensile strengths.

We do not have this opportunity 
in 3D printing.

We can use a heated build plate. But that

only influences the first few layers.

Besides, we need the printed strands to

cool off quickly so that they keep their shape.

We can only print the next layer

if the layer underneath 
has already hardened.

We cannot keep a constant high temperature 
like we can in the spinning chamber.

The SLS method allows 
for better conditions

concerning the tensile strength

and the structures did show better values.

We have a second possibility to increase the 
tensile strength of synthetic fibers

which is by stretching them 
after spinning.

The fibers are guided through cylinders 
and subjected to tensile forces.

This increases the degree of 
crystallinity even more.

The molecules are forced 
to align even more.

This decreases the fiber diameter and 
makes the fiber more fine, softer

and at the same time stronger.

That explains why textile fibers have 
much higher tensile strengths

while at the same time being much finer 
than anything you can 3D print at the moment.

Furthermore, textile fibers have the advantageous 
capability of warming us by isolating air.

Every little chamber that can entrap air 
turns a fabric into a warming structure

when worn on the body. 
Fabrics consist of threads

and threads consist of fibers,

as you can see on this microscope picture.

It's not a picture of a carpet, 
it's fabric

and the little single fibers would not be 
visible with the naked eye.

The gaps between the fibers 
isolate air.

At the same time, the gaps are important 
for the transportation of moisture.

Sweat can evaporate and go through the fabric.
In conclusion,

fabrics can warm us and at the same time 
protect us against overheating.

At the moment, we cannot 3D print such fine 
miniature fibers. We are still quite limited

when it comes to fineness. We cannot efficiently 
3D print chambers to entrap air

like the ones we can find in fabrics 
made of textile fibers.

Some things cannot be done yet 
in 3D printing. But what can we do

in 3D printing instead? We have an immense 
freedom of design that can be applied

mostly in shoes and accessories,

for example bracelets, necklaces 
or glasses.

The benefits can be used for costumes.

For example, in the movie "Black Panther", 
several crowns were 3D printed.

Theoretically, the process is sustainable,

just because it is additive manufacturing.

Material is only built where it is needed 
for the desired shape.

This is in stark contrast to the 
production of clothes.

When you cut the fabric, you can achieve 
a utilization ratio of maybe 90%.

Just because pattern pieces 
have many different shapes,

10% of the fabric is thrown away.

3D printing is more sustainable 
in this aspect.

Also, the materials can be reused.

Recycling is another problem 
in the fashion industry.

So it is a good thing that you can 
reuse the powder after printing.

3D printing is also very suitable for 
made-to-order production.

In the fashion industry, made-to-order 
items always lead to high costs.

Also, it is possible to create different 
material properties in the same product.

When I have the shoulder

and want it to be a bit more firm,

I can already prepare that in the 
3D model. I can decide

to create more layers. If I created the same 
piece of clothing in fabric,

I would need to have a seam, I would reinforce 
it with another fabric

or another layer of fabric. Using a 3D printer, 
this could happen in the same step.

Theoretically, it is also possible to 
integrate additional functions

like cables, LED or sensors.

There is still a question mark 
behind that.

First of all, this would not 
be everyday wear,

and secondly, this is not 
state of the art yet.

Another benefit might be to create the 
whole garment in one step.

Right now, a fabric is created out of 
threads out of textile fibers.

Then, the fabric needs to be cut, the 
pieces need to be sewn together,

maybe it is dyed after that. 
Different processes,

executed at different locations.
With 3D printing,

everything could happen in the same step.

But only if the garment can fit into 
the build volume of a printer.

If we print A4 sized pieces and 
assemble them afterwards,

we are still in the same situation of 
having to connect many pieces.

The software developed by Nervous System 
is a smarter solution.

The software digitally folds the dress. 
The dress is then printed in the folded state,

significantly reducing 
the needed build volume.

The dress is hidden somewhere 
in the block of powder.

The powder is removed, 
a bit like in archeology,

the dress will get cleaned off 
and opened.

This is a good option to really 
use the benefits of 3D printing.

The disadvantages or challenges are

the insufficient tensile strength,
resulting from the process itself

and there is not a lot we can 
do about it. We are still very limited

in terms of fineness. The standard nozzle 
diameter is 0.4 millimeters.

Fiber diameters are more 
in the micrometer range.

That is a significant difference. The fineness 
is very important for the next-to-skin-comfort,

for the transportation of moisture and for 
the capability to warm us.

This is fundamental and without it, 
the aspects of wearing comfort

cannot be guaranteed 
when we 3D print textile structures.

Time and costs are still 
quite problematic in 3D printing.

It takes af long time 
and it is very expensive.

Again, this is not suitable for 
everyday wear, only for individual pieces.

We also still have to discuss 
care instructions.

Can you wash a 3D printed garment 
at all? If I wear a piece of clothing every day,

I want to be able to wash it.

When we talk about garments, 
we also need to talk about fastenings,

you need to somehow get inside 
the piece of clothing.

So, zippers, buttons, hooks, eyelets, 
all of this needs to be thought of

if we want to print 
everything in one piece.

In conclusion, the construction of fabrics 
made from threads made from fibers

is still unbeatable in regards of 
wearing comfort.

There are not yet applicable solutions

to imitate the properties in 3D printing.

At the current state of the art, 
3D printed clothes are not only not the future,

they aren't even the present.
Because the present means

fabrics made of textile fibers and that 
works really well for our wearing comfort.

3D printed structure cannot 
provide that yet.

That does not mean that we 
should stop the research.

Whoever said before that they had 
success when printing clothes,

I am very interested to hear about that.
Maybe there are some aspects

that I have not thought about.
But we should not forget

the basic function of clothes. The 3D 
printed clothes that I showed in the beginning,

those are amazing artworks, I love 
them and I want to see more of them.

But I want to remind everyone that 
clothes should warm us,

that in general, it should be opaque 
and that the climate exchange

and the transportation of moisture has 
to be guaranteed. I find it a bit difficult

to put so much hope on 3D printing

to fundamentally change 
the whole fashion industry.

Because the fashion industry has 
a lot of serious problems,

ecological problems,

but also social and societal problems.

But I don't think we should simply hope 
to develop new technologies

and tell us that the sustainability problem 
can be solved by 3D printing

all of our clothes. Please conduct 
further research.

But please don't forget the basic 
functions of clothes and do not think

that a new technology will solve all the 
problems of the fashion industry.

I advise everyone 
to revolutionize the fashion industry.

But please do not think that 3D printing 
is the universal solution for that.

And now I am finished with my 
presentation and I thank you all for listening.

<i>applause</i>

Herald Angel Noujoum: Yes, thank you, 
that was quite a precision landing, I'm afraid

we don't have time left for questions, I am sorry 
to everyone flocking to the microphones right now.

But you can see here where you can 
talk to Rebekka,

you can find her and ask her questions 
on Twitter under @Kurfuerstin.

You can also talk to her right now after 
the talk. Maybe not right here,

but somewhere in the back. 
She also needs to read her post cards.

I'm sure there will be time 
and the possibility

to talk to her or each other about 
3D printing and 3D printed clothes.

Please give another round of applause.

<i>applause</i>

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