0:00:00.000,0:00:10.808
<i>36C3 preroll music</i>

0:00:13.623,0:00:21.449
Herald Angel Noujoum: Hello and [br]welcome to our next talk,

0:00:21.449,0:00:26.630
Why 3D printing clothes is NOT the future. [br]Short question to the audience:

0:00:26.630,0:00:32.103
Who of you has already 3D printed anything? [br]Please raise your hand.

0:00:32.103,0:00:35.640
That's what I thought, I estimate that's about [br]80 % of the audience in this hall.

0:00:35.640,0:00:38.860
I am not surprised, it is the topic of this talk, [br]that's why you are here.

0:00:38.860,0:00:41.606
Second question: Who of you

0:00:41.606,0:00:47.059
has already tried 3D printing clothes?[br]Please raise your hand again.

0:00:47.059,0:00:54.539
I see four people.[br]So, how did it go?

0:00:54.539,0:00:58.082
One person indicates [br]that it worked out well,

0:00:58.082,0:01:02.399
the others are showing hand gestures [br]of "not that well".

0:01:02.399,0:01:05.513
Who of all the people that have [br]already 3D printed

0:01:05.513,0:01:09.930
has thought about printing clothes?

0:01:09.930,0:01:12.869
Ok, about 10 people have thought [br]about that.

0:01:12.869,0:01:17.540
Our next speaker, Rebekka, will tell you [br]why it might not be the best idea

0:01:17.540,0:01:22.320
to 3D print clothes. [br]On the internet

0:01:22.320,0:01:27.270
and especially Twitter, Rebekka is known[br]by her nickname Kurfuerstin

0:01:27.270,0:01:31.619
and she is a clothing technician. Her [br]research includes

0:01:31.619,0:01:35.120
traditional apparel production, she has [br]worked in a fashion company,

0:01:35.120,0:01:38.737
at the theater and at a tv show.

0:01:38.737,0:01:42.459
Also, she is researching innovative [br]techniques such as 3D printing

0:01:42.459,0:01:46.963
and virtual clothing simulation,

0:01:46.963,0:01:50.709
meaning software that realistically [br]simulates clothes

0:01:50.709,0:01:55.770
on a virtual avatar.

0:01:55.770,0:01:58.940
Have fun with the talk , [br]I hope you will learn a lot

0:01:58.940,0:02:01.953
and please welcome Rebekka

0:02:01.953,0:02:03.663
with a round of applause. [br]Thank you.

0:02:03.663,0:02:08.490
<i>applause</i>

0:02:08.490,0:02:12.280
Speaker Rebekka/Kurfuerstin: I just [br]received some mail really quick,

0:02:12.280,0:02:17.312
but that won't stop me from giving [br]my talk. Welcome,

0:02:17.312,0:02:22.140
nice to see you all here, in this hall [br]and on the live stream and...

0:02:22.140,0:02:26.480
additional mail, okay, a lot happening [br]on this stage. I will maybe read that later,

0:02:26.480,0:02:33.079
but it is great to know that the [br]post office system works!

0:02:33.079,0:02:38.129
The title of my talk is "Why 3D printing [br]clothes is NOT the future".

0:02:38.129,0:02:44.087
It will be about the properties of [br]3D printed clothes and

0:02:44.087,0:02:50.599
what would need to happen in order [br]for it to be a serious alternative

0:02:50.599,0:02:54.402
for everyday wear. I was just introduced [br]as a clothing technician.

0:02:54.402,0:02:57.749
In case you don't know what this strange [br]combination of words means,

0:02:57.749,0:03:03.689
clothes and technology, [br]a short explanation.

0:03:03.689,0:03:07.319
When clothes are made, at one side,

0:03:07.319,0:03:12.511
you have the design, the idea.[br]But the realization, the production,

0:03:12.511,0:03:16.989
happens somewhere else entirely[br]and by some other person.

0:03:16.989,0:03:20.920
In a simplified way, a person creates [br]the design for a dress

0:03:20.920,0:03:24.069
and says: I designed this dress.

0:03:24.069,0:03:29.520
So they have a nice picture from which [br]you can learn some information, but not much.

0:03:29.520,0:03:33.560
And they go to a factory and say: [br]please make this dress.

0:03:33.560,0:03:37.720
The production will kindly ask: [br]where is the table of information?

0:03:37.720,0:03:41.650
Because the production site wants to [br]have all the information about the dress.

0:03:41.650,0:03:47.099
And the designer then asks: what? [br]And the production then asks: what?

0:03:47.099,0:03:49.920
And that would be the end of it.

0:03:49.920,0:03:53.529
Because the factory wants to know, [br]which fabric do we need for the dress,

0:03:53.529,0:03:58.730
and how much? Which sizes will be made, [br]and how many dresses in which sizes?

0:03:58.730,0:04:02.360
Which machines do we need for that, what [br]text will be on the care instruction labels

0:04:02.360,0:04:05.760
and what will be the exact position of the [br]labels on the side seam in cm?

0:04:05.760,0:04:11.360
All those questions cannot be answered [br]by the illustration of the dress.

0:04:11.360,0:04:14.959
And that is where clothing technology comes in,[br]as the intersection between design and production.

0:04:14.959,0:04:20.570
It's about the technical feasibility and

0:04:20.570,0:04:25.110
what needs to be done [br]to manufacture clothes.

0:04:25.110,0:04:29.590
It's about materials, quality, [br]prices and locations.

0:04:29.590,0:04:34.710
Where should the production take place, [br]and when?

0:04:34.710,0:04:37.610
All these questions need answers [br]and that is the responsibility

0:04:37.610,0:04:43.169
of clothing technicians. [br]And this kind of reality check,

0:04:43.169,0:04:48.379
the perspective of feasibility, is the perspective [br]I also chose to examine 3D printing.

0:04:48.379,0:04:52.090
If you search for the words "3D print" and [br]"clothes", you will get headlines like these.

0:04:52.090,0:04:58.930
For example: 3D printing will bring [br]flexibility into the fashion industry.

0:04:58.930,0:05:03.110
Or: The fashion of the future. Or: Will the [br]street wear of the future be 3D printed?

0:05:03.110,0:05:08.020
Or: Can 3D printing fundamentally [br]change the fashion industry?

0:05:08.020,0:05:12.070
[br]A few years ago, the headlines were [br]even more sensational.

0:05:12.070,0:05:15.759
They were predicting that by 2020, we [br]would print a sweater in the morning,

0:05:15.759,0:05:19.270
melt it down in the evening and then [br]print a new one the next day.

0:05:19.270,0:05:21.700
Nowadays, the predictions have [br]become a bit more careful,

0:05:21.700,0:05:24.400
at least with a question mark at the end.

0:05:24.400,0:05:28.889
But even from these headlines, [br]you get the sense that something

0:05:28.889,0:05:33.423
will fundamentally change the [br]fashion industry.

0:05:33.423,0:05:37.990
There is also the hope of [br]a sustainable production

0:05:37.990,0:05:41.180
with the argument, that the procedure [br]of 3D printing is sustainable.

0:05:41.180,0:05:45.287
Sustainability is a major topic [br]in the fashion industry.

0:05:45.287,0:05:48.539
The question is if 3D printing [br]might be the solution.

0:05:48.539,0:05:54.569
Clothes have already been 3D printed,

0:05:54.569,0:05:58.289
it's not even that new or unrealistic.

0:05:58.289,0:06:02.300
There are entire 3D printed collections and [br]I will show some examples now.

0:06:02.300,0:06:07.990
In Israel, Danit Peleg printed her entire [br]final collection of five outfits.

0:06:07.990,0:06:13.169
In Israel, Danit Peleg printed her entire [br]final collection of five outfits.

0:06:13.169,0:06:18.449
One example is the two piece outfit on[br]the right, a top and a floor length skirt.

0:06:18.449,0:06:25.110
The skirt has been printed using [br]only desktop printers,

0:06:25.110,0:06:30.169
meaning that it consists of [br]modules of A4 size

0:06:30.169,0:06:34.169
that have been connected afterwards.

0:06:34.169,0:06:37.930
It is flexibel, because it was printed [br]with a flexible filament,

0:06:37.930,0:06:42.160
but also because it made up [br]of a zigzag structure

0:06:42.160,0:06:45.936
that allows for it to pull on it.

0:06:45.936,0:06:50.889
If you pull it up, it bounces up and down.

0:06:50.889,0:06:55.020
The jacket is the first [br]3D printed ready-to-wear

0:06:55.020,0:07:00.039
article of clothing that [br]you can order online,

0:07:00.039,0:07:04.970
in limited edition of 100 pieces.

0:07:04.970,0:07:10.400
It costs 1500 $.

0:07:10.400,0:07:13.860
You can choose the color and [br]some writing on the back

0:07:13.860,0:07:17.991
and then the jacket will be [br]printed in 100 hours.

0:07:17.991,0:07:24.110
Another example is from the [br]design collective Nervous System,

0:07:24.110,0:07:28.969
who have developed the Kinematics System.

0:07:28.969,0:07:32.910
It consists of triangles [br]that are connected by hinges,

0:07:32.910,0:07:38.397
making the whole structure flexible.

0:07:38.397,0:07:43.830
But it is made of a hard material. [br]It can move, but it is not elastic

0:07:43.830,0:07:48.530
and it rattles a bit when you move.[br]They also developed an opaque version.

0:07:48.530,0:07:53.199
[br]The dress on the right is based[br]on the same triangle structure,

0:07:53.199,0:07:58.291
but there are some kind of [br]petals on top of it.

0:07:58.291,0:08:03.650
So the dress is opaque.

0:08:03.650,0:08:09.530
A third example is the Pangolin Dress

0:08:09.530,0:08:13.159
which is also made of a structure [br]of interlocked modules

0:08:13.159,0:08:16.360
that can move on top of [br]and into each other,

0:08:16.360,0:08:21.789
thus making the structure flexible.

0:08:21.789,0:08:27.449
You can move in the dress and the [br]dress adjusts to your movements.

0:08:27.449,0:08:31.148
One of the people working on it is [br]Travis Fitch, a designer working in New York.

0:08:31.148,0:08:35.229
I contacted Travis and said: I am a [br]clothing technician, I love numbers.

0:08:35.229,0:08:39.473
How do you know if a newly developed [br]structure is suitable for a dress?

0:08:39.473,0:08:43.959
How do you know if the elasticity [br]is high enough

0:08:43.959,0:08:49.500
to use it in a piece of clothing?

0:08:49.500,0:08:53.890
Do you do laboratory tests?

0:08:53.890,0:08:59.630
And he answered, well, I pull at it and then [br]I either say it is okay or not.

0:08:59.630,0:09:03.040
So the clothing technician in me [br]came through and said,

0:09:03.040,0:09:08.490
well how about numbers? So I offered [br]to test some of his structures,

0:09:08.490,0:09:15.010
[br]to conduct some laboratory experiments

0:09:15.010,0:09:18.930
in order to examine how the properties [br]can be expressed in numbers and units.

0:09:18.930,0:09:23.324
Those were only three examples. [br]There are many more

0:09:23.324,0:09:29.070
on catwalks and in fashion shows. It is clear [br]that those examples are not everyday wear.

0:09:29.070,0:09:34.410
They are special made-to-order products,

0:09:34.410,0:09:38.200
it takes months to create them,

0:09:38.200,0:09:42.529
they consist of 300 different pieces [br]that need to be assembled.

0:09:42.529,0:09:47.190
But the headlines about fundamentally [br]changing the fashion industry

0:09:47.190,0:09:50.660
are about everyday wear.

0:09:50.660,0:09:55.043
Custom-made items on a catwalk [br]do not change the whole industry.

0:09:55.043,0:09:58.720
Something needs to happen [br]before that applies to everyday wear.

0:09:58.720,0:10:03.779
That is why I ask, what kind of properties [br]do clothes need to have

0:10:03.779,0:10:07.870
in order to be everyday wear, [br]meaning clothes

0:10:07.870,0:10:13.846
that we can wear every day and [br]for every occasion?

0:10:13.846,0:10:19.310
First of all, clothes need [br]to be comfortable.

0:10:19.310,0:10:24.300
There are four aspects of wearing comfort.

0:10:24.300,0:10:29.540
First, the psychological wearing comfort [br]which is about fashion trends,

0:10:29.540,0:10:36.379
societal norms and individuality.

0:10:36.379,0:10:40.240
The fact that I am standing here [br]in a t-shirt and a hoodie

0:10:40.240,0:10:44.339
is particularly apt for this congress.

0:10:44.339,0:10:47.610
On another business conference I might [br]have worn something different.

0:10:47.610,0:10:52.360
And that people are driving around [br]in onesies and goose costumes

0:10:52.360,0:10:57.856
is also very specific for this group right here.[br]<i>laughter</i>

0:10:57.856,0:11:01.661
What I mean by this is that people feel [br]comfortable wearing this in this specific context

0:11:01.661,0:11:04.120
and might not feel at ease [br]in another context,

0:11:04.120,0:11:06.510
although the clothes themselves [br]have not changed.

0:11:06.510,0:11:11.220
That is the psychological wearing comfort.

0:11:11.220,0:11:16.310
The next-to-skin-comfort is about [br]the feeling of something on the skin.

0:11:16.310,0:11:21.420
Surfaces can be soft or scratchy, [br]they can also cause allergies.

0:11:21.420,0:11:26.190
So it is about the direct contact [br]on the skin.

0:11:26.190,0:11:30.930
The physiological wearing comfort is very [br]important as well. It's about the climate control

0:11:30.930,0:11:35.055
of the body and about how clothes can keep [br]us warm but also allow for moisture to evaporate.

0:11:35.055,0:11:38.890
The human body has this amazing system [br]of protecting us from overheating.

0:11:38.890,0:11:44.490
We start to sweat and [br]the moisture evaporates.

0:11:44.490,0:11:49.540
But the evaporation has to happen [br]through the fabric of our clothes.

0:11:49.540,0:11:54.100
Some clothes allow for better evaporation [br]than others.

0:11:54.100,0:11:58.870
This aspect is incredibly important for our [br]comfort when wearing clothes.

0:11:58.870,0:12:05.209
The fourth aspect is the [br]ergonomical wearing comfort

0:12:05.209,0:12:10.811
which is about freedom of movement [br]and that is what I examined in detail.

0:12:10.811,0:12:14.639
Freedom of movement in clothes is [br]achieved by the fit of a piece of clothing,

0:12:14.639,0:12:20.350
mainly meaning how tight it is on the body.

0:12:20.350,0:12:25.860
Secondly, it is achieved by the elasticity [br]of the materials used.

0:12:25.860,0:12:29.380
This is very important because there are parts [br]of our body where we need 50% stretching,

0:12:29.380,0:12:35.070
for example at our knees and elbows.

0:12:35.070,0:12:38.790
If you move your arm like this, then the [br]clothes need to allow this movement

0:12:38.790,0:12:42.019
without tearing apart.

0:12:42.019,0:12:47.670
Without elasticity, [br]the sleeve would be destroyed

0:12:47.670,0:12:51.940
or would change its form and create buckles.

0:12:51.940,0:12:56.570
If we have a very tight sleeve

0:12:56.570,0:13:00.300
made from a material that is not elastic

0:13:00.300,0:13:03.486
the sleeve at the elbow would take [br]the shape of our elbow.

0:13:03.486,0:13:07.796
So we need a material with [br]the capability to rebound.

0:13:07.796,0:13:10.579
After we have moved the arm like this, [br]the sleeve at the elbow

0:13:10.579,0:13:15.230
will go back to its original shape.

0:13:15.230,0:13:18.730
So if a material is not elastic, [br]it is not that suitable for clothes.

0:13:18.730,0:13:22.000
It is possible, but then it needs to be [br]compensated by the cut of the clothes,

0:13:22.000,0:13:25.199
in that case, it cannot be too tight. [br]If a piece of clothing is loose fit,

0:13:25.199,0:13:29.160
the elasticity of the fabric [br]is not that important.

0:13:29.160,0:13:35.339
I wanted to examine the influencing [br]factors on the elastic properties

0:13:35.339,0:13:39.389
of 3D printed structures in order [br]to actively influence the elasticity.

0:13:39.389,0:13:43.315
This could be used

0:13:43.315,0:13:47.226
to enhance the wearing comfort [br]of 3D printed clothes

0:13:47.226,0:13:54.320
and thereby get us a bit closer to [br]3D printed everyday wear.

0:13:54.320,0:13:59.805
Elasticity in textile structures, fabrics, [br]is achieved by two aspects.

0:13:59.805,0:14:04.050
First, a material itself can be elastic.

0:14:04.050,0:14:08.260
In fabrics, this is mostly elastane.

0:14:08.260,0:14:11.720
Elastane can be stretched 300% [br]and will return to its original length.

0:14:11.720,0:14:15.758
It is used in a majority of clothes,

0:14:15.758,0:14:22.860
mostly in the ratio 98% cotton and 2% elastane.

0:14:22.860,0:14:26.903
2% are enough to make a shirt [br]elastic enough to easily put it on

0:14:26.903,0:14:31.967
while at the same time being tight [br]and not starting to buckle after wearing.

0:14:31.967,0:14:36.170
The second possibility is structural elasticity.

0:14:36.170,0:14:41.370
In clothing, this is mainly achieved [br]by creating knitwear.

0:14:41.370,0:14:47.320
If you pull at knitwear,

0:14:47.320,0:14:50.579
the loops will change their shape.

0:14:50.579,0:14:54.870
In this manner, [br]you can create an elastic structure,

0:14:54.870,0:14:59.903
[br]even with materials with low elasticity.

0:14:59.903,0:15:04.994
For example, cotton fibers are [br]not very elastic. But if you create a knitwear

0:15:04.994,0:15:07.949
made of cotton threads, [br]the fabric can be very flexible and elastic.

0:15:07.949,0:15:13.899
In 3D printed structures,

0:15:13.899,0:15:18.660
an elastic material can be used as well, [br]for example TPU.

0:15:18.660,0:15:23.449
TPU is short for thermoplastic polyurethane. [br]Polyurethane is a primary part of elastane, too.

0:15:23.449,0:15:28.360
So TPU and elastane have very similar [br]properties based on their chemical composition.

0:15:28.360,0:15:38.259
Structural elasticity is also possible.

0:15:38.259,0:15:43.680
It is possible to print meshes,

0:15:43.680,0:15:48.459
but you can also create different shapes[br]like curves, arches, helices or springs.

0:15:48.459,0:15:53.050
In short, shapes that you can [br]compress or pull at,

0:15:53.050,0:15:58.350
so that you will first pull at the structure [br]before pulling at the material itself.

0:15:58.350,0:16:02.180
However, the design depends [br]on the printing method. There are several

0:16:02.180,0:16:06.380
different methods and not all of them are [br]equally suited to create certain shapes.

0:16:06.380,0:16:11.550
For my research, I focused on two of them.

0:16:11.550,0:16:16.360
First, the FLM, [br]short for fused layer modeling,

0:16:16.360,0:16:20.779
sometimes also called FDM, [br]short for fused deposition modeling.

0:16:20.779,0:16:25.197
You heat a thermoplastic filament

0:16:25.197,0:16:29.759
and push it through a nozzle

0:16:29.759,0:16:33.839
The nozzle then lays the strand of material [br]on the printing bed.

0:16:33.839,0:16:39.720
All layers on top of each other [br]make the object.

0:16:39.720,0:16:46.230
If an object has an overhang [br]like the shape on the left,

0:16:46.230,0:16:50.920
you need support structures.

0:16:50.920,0:16:56.029
In every layer, the extruder will also [br]build the supporting columns.

0:16:56.029,0:17:00.000
When the object is finished,

0:17:00.000,0:17:04.530
the support structures can be removed.

0:17:04.530,0:17:09.258
This is not a problem for hard materials,

0:17:09.258,0:17:13.770
you can easily break it off [br]and sand the surface.

0:17:13.770,0:17:17.890
But for elastic materials, [br]it's a different situation.

0:17:17.890,0:17:22.220
If you pull at it, it will not break off, [br]but simply stretch.

0:17:22.220,0:17:26.859
So if you want to print elastic shapes [br]with overhangs or interlockings,

0:17:26.859,0:17:31.759
this method is not recommended.

0:17:31.759,0:17:34.700
The support structures [br]cannot be broken off,

0:17:34.700,0:17:38.380
they would have to be cut off [br]with scissors,

0:17:38.380,0:17:41.309
so that would take a long time.

0:17:41.309,0:17:43.090
Interjection: Water soluble support structures!

0:17:43.090,0:17:47.345
Speaker: Yes, good idea, unfortunately [br]that does not work for TPU yet.

0:17:47.345,0:17:49.890
Waterbased support structures [br]are usually made of PVA.

0:17:49.890,0:17:54.392
you can remove them with water afterwards.

0:17:54.392,0:18:01.730
But the melting temperatures [br]of PVA and TPU do not match.

0:18:01.730,0:18:06.880
TPU requires a very high temperature, [br]I printed with 215°C.

0:18:06.880,0:18:10.564
At this temeprature, PVA is already decomposing, [br]its melting temperature is lower.

0:18:10.564,0:18:16.960
So it is a good idea, but at the moment [br]it does not work yet.

0:18:16.960,0:18:21.390
I am sure that something will be developed

0:18:21.390,0:18:26.720
to solve this problem, though.

0:18:26.720,0:18:30.410
The other method is SLS, [br]short for selective laser sintering.

0:18:30.410,0:18:34.500
An entire layer of powder is laid [br]on the build plate.

0:18:34.500,0:18:40.391
A laser melts the fine grain powder in order

0:18:40.391,0:18:44.370
to create the desired shape layer by layer.[br]In this case,

0:18:44.370,0:18:50.001
the powder itself is the support structure, [br]so you do not need to print

0:18:50.001,0:18:56.480
supporting columns. In the end, the entire [br]printer is filled with a block of powder

0:18:56.480,0:19:00.794
and somewhere in there,[br]the object can be found.

0:19:00.794,0:19:06.970
The powder is removed and can be reused.

0:19:06.970,0:19:13.570
For my research, [br]I examined several structures.

0:19:13.570,0:19:17.929
The ones on the left and in the middle [br]are created from powder.

0:19:17.929,0:19:25.380
So it was possible to create some height [br]and chain-like shapes.

0:19:25.380,0:19:32.400
I had different sizes.

0:19:32.400,0:19:36.909
The smaller size is much more flexible,

0:19:36.909,0:19:43.070
you can easily move it and fold it.

0:19:43.070,0:19:46.470
The modules can be shifted [br]into each other.

0:19:46.470,0:19:51.239
You can compress it and pull at it [br]and the structure is very flexible.

0:19:51.239,0:19:57.667
As I said, for the other 3D printing method, [br]the possibilities in shape were limited.

0:19:57.667,0:20:01.850
This structure is based on a pattern of rhombs [br]that was extruded.

0:20:01.850,0:20:08.780
If you pull at it, the shape [br]of the rhomb changes

0:20:08.780,0:20:13.264
before the material itself is strained.

0:20:13.264,0:20:16.620
Again, I had different variations in size and height

0:20:16.620,0:20:21.600
in order to examine the influencing factors [br]on the elastic properties.

0:20:21.600,0:20:26.279
in order to examine the influencing factors [br]on the elastic properties.

0:20:26.279,0:20:30.489
How can you examine [br]elastic properties at all?

0:20:30.489,0:20:36.215
How can you examine [br]elastic properties at all?

0:20:36.215,0:20:41.211
With a so-called tensile test.

0:20:41.211,0:20:47.370
You don't test a piece of clothing, [br]you only test a fabric swatch.

0:20:47.370,0:20:53.060
The swatch is clamped into a tensile test machine [br]which then pulls with constant velocity.

0:20:53.060,0:20:57.501
The corresponding software automatically [br]creates a diagram like the one on the right.

0:20:57.501,0:21:03.480
It shows the elongation in %,

0:21:03.480,0:21:08.250
meaning how long the fabric swatch [br]has been stretched,

0:21:08.250,0:21:12.230
and on the other axis [br]the tensile strength in N,

0:21:12.230,0:21:18.090
how much strength is needed in order to [br]achieve this elongation of the fabric swatch.

0:21:18.090,0:21:23.370
This diagram shows the elongation, [br]the elasticity and the tensile strength.

0:21:23.370,0:21:26.820
I need to stress that elongation and [br]elasticity is not the same.

0:21:26.820,0:21:33.160
You can stretch something and it [br]might have just gotten longer.

0:21:33.160,0:21:37.490
If I stretch something

0:21:37.490,0:21:41.179
and it returns to its original length, [br]it is elastic.

0:21:41.179,0:21:45.730
So that is a different property,

0:21:45.730,0:21:51.190
which you can also gather [br]from the stress-elongation-diagram.

0:21:51.190,0:21:57.030
I tested all of my structures this way.

0:21:57.030,0:22:01.110
Of course, you need to test several specimen [br]in order to generate average values.

0:22:01.110,0:22:05.656
So I had my numbers and units.

0:22:05.656,0:22:09.650
But what do I do with that?

0:22:09.650,0:22:17.059
I still need to know if these numbers are [br]good or bad. There is a recommendation

0:22:17.059,0:22:22.799
by the Dialog Textil Bekleidung in cooperation [br]with the German Fashion Mode Verband,

0:22:22.799,0:22:27.860
It is not a standard or a law, [br]clothes do not have to have these properties.

0:22:27.860,0:22:32.350
But it is a recommendation, what stretch properties [br]clothing should approximately have

0:22:32.350,0:22:37.640
and what kind of forces [br]they should withstand.

0:22:37.640,0:22:41.370
This is a small extract. [br]It is divided by products,

0:22:41.370,0:22:46.020
so trousers and skirts have different [br]specifications opposed to underwear.

0:22:46.020,0:22:50.299
If it is far from the body, meaning loose fit, [br]lower tensile strengths suffice.

0:22:50.299,0:22:54.514
If a piece of clothing is loose fit,

0:22:54.514,0:23:00.610
the stretching properties [br]are not that important.

0:23:00.610,0:23:03.270
So I compared these numbers to mine [br]and I found

0:23:03.270,0:23:08.039
that the elongations of my structures [br]were great.

0:23:08.039,0:23:13.591
But the maximum force was not reached.

0:23:13.591,0:23:18.040
So I can stretch my structures just fine,

0:23:18.040,0:23:24.340
but I do not need a lot of force to tear [br]them apart and that is a bad result.

0:23:24.340,0:23:28.850
If I bend my elbow [br]and the sleeve is destroyed,

0:23:28.850,0:23:32.520
I do not want to use this structure [br]for clothes.

0:23:32.520,0:23:35.870
So the tensile strength of the [br]3D printed structures is lower

0:23:35.870,0:23:41.180
than the recommended [br]properties for clothes.

0:23:41.180,0:23:45.279
I also wanted to examine the influencing [br]factors on the elastic properties.

0:23:45.279,0:23:51.090
From my results, I could see that the size of [br]the modules influences the properties.

0:23:51.090,0:23:56.929
The larger sizes show higher values [br]than the smaller variations.

0:23:56.929,0:24:01.864
However, the larger variations do [br]not feel and move like fabric.

0:24:01.864,0:24:07.018
The smaller variations are [br]more fabric-like,

0:24:07.018,0:24:11.115
but they didn't show very good [br]tensile strengths.

0:24:11.115,0:24:15.240
Aside from that, there was another [br]influencing factor: the slicing software.

0:24:15.240,0:24:23.300
The slicing software has two main tasks.

0:24:23.300,0:24:29.299
Firstly, it slices the object into layers. Secondly, [br]it transfers the information to the 3D printer,

0:24:29.299,0:24:34.590
where the extruder has to be in order to [br]create the shape of each layer.

0:24:34.590,0:24:39.210
For example, if you want to print a vase [br]like the one on the left, the first layer

0:24:39.210,0:24:43.789
would be filled completeley, because we want [br]to fill the vase with water and it should not leak.

0:24:43.789,0:24:48.460
The path of the extruder could look like this, [br]it would go in rows

0:24:48.460,0:24:52.100
from one side to the other in order to [br]completely fill the circle.

0:24:52.100,0:24:55.600
The second layer would be a ring [br]and the extruder might

0:24:55.600,0:25:00.970
take a path like this, but a different [br]path is also possible.

0:25:00.970,0:25:07.121
There are many different slicing programs [br]with many setting options.

0:25:07.121,0:25:12.539
I took a closer look and I found [br]that the extruder

0:25:12.539,0:25:17.820
took a very specific path for [br]my rhomb structures.

0:25:17.820,0:25:23.450
It went to the intersection and then [br]turned around. Under the microscope,

0:25:23.450,0:25:27.620
you can see that this is exactly the place [br]where the structure was torn apart.

0:25:27.620,0:25:33.190
The extruder did not cross the [br]intersection even once.

0:25:33.190,0:25:37.190
At this point, the strands of material [br]are only connected when a new,

0:25:37.190,0:25:40.989
hot strand melts a little bit into [br]the other, already cold one.

0:25:40.989,0:25:45.309
But due to the fact that the extruder [br]did not cross the intersection, it created

0:25:45.309,0:25:52.930
a predetermined breaking point. That [br]is exactly where the structure was torn apart.

0:25:52.930,0:25:57.970
In another variation that was based on the [br]same shape, the slicing software decided

0:25:57.970,0:26:01.960
something else. The extruder took the path [br]to the bending point of the rhomb.

0:26:01.960,0:26:07.490
Consequently, this is the point [br]where it was torn apart.

0:26:07.490,0:26:11.870
That is why the test samples look [br]differently after the tensile test.

0:26:11.870,0:26:18.850
That also explains the low tensile [br]strength of the structures.

0:26:18.850,0:26:21.932
The tensile test machine did not pull at the [br]material as much as at these connection points

0:26:21.932,0:26:28.340
and depending on how strong these are,

0:26:28.340,0:26:33.549
the structure can be torn apart easily.

0:26:33.549,0:26:37.680
This means that the method itself [br]limits the tensile strength.

0:26:37.680,0:26:42.809
Now, I tested eight different structures,[br]eight different variations.

0:26:42.809,0:26:46.309
You might ask now how I came to the [br]conclusion that 3D printing clothes

0:26:46.309,0:26:53.075
is not recommended in general.

0:26:53.075,0:26:58.750
Maybe a different structure would show [br]a higher tensile strength.

0:26:58.750,0:27:03.610
Yes, maybe. But the method itself creates [br]limitations concerning the properties.

0:27:03.610,0:27:09.900
We have to go deeper and look [br]at the molecules.

0:27:09.900,0:27:16.581
Textile fibers naturally have a [br]very high tensile strength.

0:27:16.581,0:27:24.290
On the inside, natural fibers like cotton, [br]wool or linen show a regular

0:27:24.290,0:27:30.241
arrangement of molecular chains.

0:27:30.241,0:27:36.300
There are amorphous parts [br]and crystalline parts.

0:27:36.300,0:27:42.159
The strands that you can see on the [br]right depict molecular chains.

0:27:42.159,0:27:46.620
The amorphous parts, [br]where the molecules are

0:27:46.620,0:27:51.000
tangled like a plate of spaghetti, [br]are not stable.

0:27:51.000,0:27:57.630
The crystalline parts, where they show a [br]regular arrangement, are stable.

0:27:57.630,0:28:03.862
Natural fibers show a high degree of [br]crystalline parts which translates

0:28:03.862,0:28:09.040
to a high tensile strength. Fibers naturally [br]show higher tensile strengths

0:28:09.040,0:28:13.856
than my 3D printed structures [br]could ever have.

0:28:13.856,0:28:17.510
And for synthetic fibers, there are [br]measures we can take to even influence

0:28:17.510,0:28:24.130
and increase the tensile strength.

0:28:24.130,0:28:30.542
There are several ways to spin a fiber, [br]at least one of them is very similar to 3D printing.

0:28:30.542,0:28:37.400
You melt synthetic material and press it [br]through a nozzle.

0:28:37.400,0:28:40.978
The extruded strand is the fiber.

0:28:40.978,0:28:45.320
The difference is that you have several [br]possibilities to influence the property

0:28:45.320,0:28:48.823
of the extruded strand or fiber.

0:28:48.823,0:28:53.880
The degree of crystallinity depends on [br]the rate of controlled cooling.

0:28:53.880,0:28:59.750
The slower a fiber cools off the more [br]time do the molecular chains have

0:28:59.750,0:29:04.007
to arrange themselves regularly.

0:29:04.007,0:29:07.850
That is why the spinning chambers [br]are really hot

0:29:07.850,0:29:12.690
in order to allow for a very slow rate [br]of controlled cooling

0:29:12.690,0:29:18.740
so that the fibers show high degrees of [br]crystallinity, resulting in high tensile strengths.

0:29:18.740,0:29:22.500
We do not have this opportunity [br]in 3D printing.

0:29:22.500,0:29:26.779
We can use a heated build plate. But that

0:29:26.779,0:29:30.880
only influences the first few layers.

0:29:30.880,0:29:35.299
Besides, we need the printed strands to

0:29:35.299,0:29:40.291
cool off quickly so that they keep their shape.

0:29:40.291,0:29:46.809
We can only print the next layer

0:29:46.809,0:29:49.179
if the layer underneath [br]has already hardened.

0:29:49.179,0:29:54.159
We cannot keep a constant high temperature [br]like we can in the spinning chamber.

0:29:54.159,0:29:58.470
The SLS method allows [br]for better conditions

0:29:58.470,0:30:03.223
concerning the tensile strength

0:30:03.223,0:30:07.150
and the structures did show better values.

0:30:07.150,0:30:11.409
We have a second possibility to increase the [br]tensile strength of synthetic fibers

0:30:11.409,0:30:15.271
which is by stretching them [br]after spinning.

0:30:15.271,0:30:21.020
The fibers are guided through cylinders [br]and subjected to tensile forces.

0:30:21.020,0:30:31.460
This increases the degree of [br]crystallinity even more.

0:30:31.460,0:30:36.380
The molecules are forced [br]to align even more.

0:30:36.380,0:30:40.179
This decreases the fiber diameter and [br]makes the fiber more fine, softer

0:30:40.179,0:30:45.840
and at the same time stronger.

0:30:45.840,0:30:50.700
That explains why textile fibers have [br]much higher tensile strengths

0:30:50.700,0:30:56.309
while at the same time being much finer [br]than anything you can 3D print at the moment.

0:30:56.309,0:30:59.977
Furthermore, textile fibers have the advantageous [br]capability of warming us by isolating air.

0:30:59.977,0:31:03.700
Every little chamber that can entrap air [br]turns a fabric into a warming structure

0:31:03.700,0:31:09.100
when worn on the body. [br]Fabrics consist of threads

0:31:09.100,0:31:13.834
and threads consist of fibers,

0:31:13.834,0:31:18.170
as you can see on this microscope picture.

0:31:18.170,0:31:21.559
It's not a picture of a carpet, [br]it's fabric

0:31:21.559,0:31:29.139
and the little single fibers would not be [br]visible with the naked eye.

0:31:29.139,0:31:33.779
The gaps between the fibers [br]isolate air.

0:31:33.779,0:31:38.000
At the same time, the gaps are important [br]for the transportation of moisture.

0:31:38.000,0:31:41.130
Sweat can evaporate and go through the fabric.[br]In conclusion,

0:31:41.130,0:31:46.220
fabrics can warm us and at the same time [br]protect us against overheating.

0:31:46.220,0:31:51.350
At the moment, we cannot 3D print such fine [br]miniature fibers. We are still quite limited

0:31:51.350,0:31:58.429
when it comes to fineness. We cannot efficiently [br]3D print chambers to entrap air

0:31:58.429,0:32:04.059
like the ones we can find in fabrics [br]made of textile fibers.

0:32:04.059,0:32:08.970
Some things cannot be done yet [br]in 3D printing. But what can we do

0:32:08.970,0:32:15.220
in 3D printing instead? We have an immense [br]freedom of design that can be applied

0:32:15.220,0:32:20.679
mostly in shoes and accessories,

0:32:20.679,0:32:24.649
for example bracelets, necklaces [br]or glasses.

0:32:24.649,0:32:29.450
The benefits can be used for costumes.

0:32:29.450,0:32:34.998
For example, in the movie "Black Panther", [br]several crowns were 3D printed.

0:32:34.998,0:32:39.520
Theoretically, the process is sustainable,

0:32:39.520,0:32:44.076
just because it is additive manufacturing.

0:32:44.076,0:32:48.059
Material is only built where it is needed [br]for the desired shape.

0:32:48.059,0:32:53.909
This is in stark contrast to the [br]production of clothes.

0:32:53.909,0:32:58.620
When you cut the fabric, you can achieve [br]a utilization ratio of maybe 90%.

0:32:58.620,0:33:03.262
Just because pattern pieces [br]have many different shapes,

0:33:03.262,0:33:07.280
10% of the fabric is thrown away.

0:33:07.280,0:33:15.017
3D printing is more sustainable [br]in this aspect.

0:33:15.017,0:33:17.899
Also, the materials can be reused.

0:33:17.899,0:33:20.870
Recycling is another problem [br]in the fashion industry.

0:33:20.870,0:33:24.440
So it is a good thing that you can [br]reuse the powder after printing.

0:33:24.440,0:33:30.270
3D printing is also very suitable for [br]made-to-order production.

0:33:30.270,0:33:34.530
In the fashion industry, made-to-order [br]items always lead to high costs.

0:33:34.530,0:33:38.909
Also, it is possible to create different [br]material properties in the same product.

0:33:38.909,0:33:42.764
When I have the shoulder

0:33:42.764,0:33:47.279
and want it to be a bit more firm,

0:33:47.279,0:33:50.797
I can already prepare that in the [br]3D model. I can decide

0:33:50.797,0:33:54.620
to create more layers. If I created the same [br]piece of clothing in fabric,

0:33:54.620,0:33:58.320
I would need to have a seam, I would reinforce [br]it with another fabric

0:33:58.320,0:34:02.440
or another layer of fabric. Using a 3D printer, [br]this could happen in the same step.

0:34:02.440,0:34:07.050
Theoretically, it is also possible to [br]integrate additional functions

0:34:07.050,0:34:13.290
like cables, LED or sensors.

0:34:13.290,0:34:18.440
There is still a question mark [br]behind that.

0:34:18.440,0:34:22.530
First of all, this would not [br]be everyday wear,

0:34:22.530,0:34:28.790
and secondly, this is not [br]state of the art yet.

0:34:28.790,0:34:33.170
Another benefit might be to create the [br]whole garment in one step.

0:34:33.170,0:34:36.769
Right now, a fabric is created out of [br]threads out of textile fibers.

0:34:36.769,0:34:39.330
Then, the fabric needs to be cut, the [br]pieces need to be sewn together,

0:34:39.330,0:34:42.070
maybe it is dyed after that. [br]Different processes,

0:34:42.070,0:34:46.370
executed at different locations.[br]With 3D printing,

0:34:46.370,0:34:52.090
everything could happen in the same step.

0:34:52.090,0:34:56.118
But only if the garment can fit into [br]the build volume of a printer.

0:34:56.118,0:35:00.230
If we print A4 sized pieces and [br]assemble them afterwards,

0:35:00.230,0:35:04.550
we are still in the same situation of [br]having to connect many pieces.

0:35:04.550,0:35:11.230
The software developed by Nervous System [br]is a smarter solution.

0:35:11.230,0:35:15.286
The software digitally folds the dress. [br]The dress is then printed in the folded state,

0:35:15.286,0:35:20.030
significantly reducing [br]the needed build volume.

0:35:20.030,0:35:25.960
The dress is hidden somewhere [br]in the block of powder.

0:35:25.960,0:35:29.810
The powder is removed, [br]a bit like in archeology,

0:35:29.810,0:35:34.094
the dress will get cleaned off [br]and opened.

0:35:34.094,0:35:37.411
This is a good option to really [br]use the benefits of 3D printing.

0:35:37.411,0:35:46.520
The disadvantages or challenges are

0:35:46.520,0:35:51.190
the insufficient tensile strength,[br]resulting from the process itself

0:35:51.190,0:35:56.180
and there is not a lot we can [br]do about it. We are still very limited

0:35:56.180,0:36:03.340
in terms of fineness. The standard nozzle [br]diameter is 0.4 millimeters.

0:36:03.340,0:36:08.695
Fiber diameters are more [br]in the micrometer range.

0:36:08.695,0:36:13.556
That is a significant difference. The fineness [br]is very important for the next-to-skin-comfort,

0:36:13.556,0:36:17.920
for the transportation of moisture and for [br]the capability to warm us.

0:36:17.920,0:36:24.720
This is fundamental and without it, [br]the aspects of wearing comfort

0:36:24.720,0:36:31.258
cannot be guaranteed [br]when we 3D print textile structures.

0:36:31.258,0:36:36.119
Time and costs are still [br]quite problematic in 3D printing.

0:36:36.119,0:36:40.650
It takes af long time [br]and it is very expensive.

0:36:40.650,0:36:45.095
Again, this is not suitable for [br]everyday wear, only for individual pieces.

0:36:45.095,0:36:48.014
We also still have to discuss [br]care instructions.

0:36:48.014,0:36:51.378
Can you wash a 3D printed garment [br]at all? If I wear a piece of clothing every day,

0:36:51.378,0:36:54.589
I want to be able to wash it.

0:36:54.589,0:36:58.082
When we talk about garments, [br]we also need to talk about fastenings,

0:36:58.082,0:37:02.144
you need to somehow get inside [br]the piece of clothing.

0:37:02.144,0:37:06.251
So, zippers, buttons, hooks, eyelets, [br]all of this needs to be thought of

0:37:06.251,0:37:12.750
if we want to print [br]everything in one piece.

0:37:12.750,0:37:17.090
In conclusion, the construction of fabrics [br]made from threads made from fibers

0:37:17.090,0:37:23.170
is still unbeatable in regards of [br]wearing comfort.

0:37:23.170,0:37:28.379
There are not yet applicable solutions

0:37:28.379,0:37:40.370
to imitate the properties in 3D printing.

0:37:40.370,0:37:44.478
At the current state of the art, [br]3D printed clothes are not only not the future,

0:37:44.478,0:37:47.257
they aren't even the present.[br]Because the present means

0:37:47.257,0:37:50.930
fabrics made of textile fibers and that [br]works really well for our wearing comfort.

0:37:50.930,0:37:55.430
3D printed structure cannot [br]provide that yet.

0:37:55.430,0:37:58.660
That does not mean that we [br]should stop the research.

0:37:58.660,0:38:01.260
Whoever said before that they had [br]success when printing clothes,

0:38:01.260,0:38:04.760
I am very interested to hear about that.[br]Maybe there are some aspects

0:38:04.760,0:38:11.587
that I have not thought about.[br]But we should not forget

0:38:11.587,0:38:17.460
the basic function of clothes. The 3D [br]printed clothes that I showed in the beginning,

0:38:17.460,0:38:21.800
those are amazing artworks, I love [br]them and I want to see more of them.

0:38:21.800,0:38:24.820
But I want to remind everyone that [br]clothes should warm us,

0:38:24.820,0:38:28.170
that in general, it should be opaque [br]and that the climate exchange

0:38:28.170,0:38:33.840
and the transportation of moisture has [br]to be guaranteed. I find it a bit difficult

0:38:33.840,0:38:38.370
to put so much hope on 3D printing

0:38:38.370,0:38:44.030
to fundamentally change [br]the whole fashion industry.

0:38:44.030,0:38:49.371
Because the fashion industry has [br]a lot of serious problems,

0:38:49.371,0:38:53.580
ecological problems,

0:38:53.580,0:38:57.250
but also social and societal problems.

0:38:57.250,0:39:01.229
But I don't think we should simply hope [br]to develop new technologies

0:39:01.229,0:39:04.440
and tell us that the sustainability problem [br]can be solved by 3D printing

0:39:04.440,0:39:09.850
all of our clothes. Please conduct [br]further research.

0:39:09.850,0:39:15.830
But please don't forget the basic [br]functions of clothes and do not think

0:39:15.830,0:39:20.323
that a new technology will solve all the [br]problems of the fashion industry.

0:39:20.323,0:39:27.140
I advise everyone [br]to revolutionize the fashion industry.

0:39:27.140,0:39:32.650
But please do not think that 3D printing [br]is the universal solution for that.

0:39:32.650,0:39:36.782
And now I am finished with my [br]presentation and I thank you all for listening.

0:39:36.782,0:39:47.155
<i>applause</i>

0:39:47.155,0:39:49.912
Herald Angel Noujoum: Yes, thank you, [br]that was quite a precision landing, I'm afraid

0:39:49.912,0:39:52.830
we don't have time left for questions, I am sorry [br]to everyone flocking to the microphones right now.

0:39:52.830,0:39:57.330
But you can see here where you can [br]talk to Rebekka,

0:39:57.330,0:40:01.409
you can find her and ask her questions [br]on Twitter under @Kurfuerstin.

0:40:01.409,0:40:04.331
You can also talk to her right now after [br]the talk. Maybe not right here,

0:40:04.331,0:40:07.330
but somewhere in the back. [br]She also needs to read her post cards.

0:40:07.330,0:40:10.780
I'm sure there will be time [br]and the possibility

0:40:10.780,0:40:14.600
to talk to her or each other about [br]3D printing and 3D printed clothes.

0:40:14.600,0:40:17.556
Please give another round of applause.

0:40:17.556,0:40:18.670
<i>applause</i>

0:40:18.670,0:40:22.280
<i>postroll music</i>

0:40:22.280,0:40:30.234
Subtitles created by c3subtitles.de in 2020. [br]Join us!